Ilyushin Il-28 Beagle: Light Attack Bomber

The Author s Yefi m Gordon is a Ru ss ian avia tion wri ter a nd photograp her . He has stu di ed Russ ia n (and Sovie t) avia tion history for th e last th irty yea rs . His pr ev ious books include Soviet X-Planes, MiG- i S, MiG-2S, Yakoleo Aircraft, a nd Ai rlife have recently published MiG-29 a nd Su-27. He lives in Moscow. Dm it ri y Komi ssa ro v is a pr ofessi on al av ia tion tra nsl at or a nd a n ed itor worki ng for Polygon Press Ltd . He has stud ied Ru ss ia n (and Sovie t) av iation hi st ory for th e last ten yea rs. His previous book s include Ilyushin 11-76 (Russ ia n and English language ed itions) a nd Mil Mi-24 Hind Attack Helicopter. He ha s also tran slat ed into En glish most of th e book s wri tten by Yefim Gordo n. He lives in Moscow.

Relat ed titl es published b )' Airlife Mil Mi -24 Hind Attack Helicop ter by Yefi m Gordon & Dmitriy Komi ssarov

Sukhoi Su-27 Flanker Air Superiority Fight er by Ye fim Gord on Mikoya n MiG-29 Fulcrum M ulti-role Fighter by Yefim Gord on Monin o - The Russian Ai r Force Mu seum by Co lin W. Prenti ce

n~hinn-28 Beagle

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LIGHT ATTACI{ BOMBER

Yefim Gordon and Ihnitriy Komissarov

Airlife

Co pyright
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British Libra ry Cataloguing-in-Puhlica tion Data

A cata logue record for thi s book is available from the British Library ISB N I 84037 351 2 All rights reserved. No part of th is book may be reproduced or transmitted in any form or by any means. electronic o r mechanical including photocopying. recording or by any informati on storage and retrieval system. without permission from the Publisher in writing. This book contai ns rare. early colour photographs and the Publisher has made every endeavour to reproduce them to the highest quality. Some. however. have been technica lly impossible to reproduce to th e standard that we no rma lly demand. but have been included beca use of their rarity and interest value. Typeset by Rowland Phototypesetting Limited. Bury St Edmunds. Suffolk Printed in Hong Kong

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ACKNOWLEDGEMENTS

The a uthors wish to express their gratitude to N igel Eastway of the Russian Aviatio n Research Trust (RA RT), who, as usual, provided assistance with photos from his extensive a rchive; to Sergey Komissarov who also supplied several previously unpublished photos; to And rey Yurgenson fo r the line drawings and Sergey Yershov for the excellent colour side views.

CONTENTS

Introduction

9

1 Breeding the Beagle 2 The Il-28 Family 3 The Beagle in Service 4 Beagles World-wide 5 The Il-28 in Detail Appendix I Acronyms and Glossary Appendix II Detail Plans

126 129

Index

142

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-73

92 11 8

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The fa mo us Soviet airc ra ft designer Sergey Vladim irov ich Ilyu shin . the fo under o f OKB-240 a nd th e creato r of many o utsta nding includin g the 11-28 tacti cal bomber. ( SlT~' .aircra . . ft .- . ... . '''. T HE

IL-28 FAM ILY ' 31

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A production I1-28R operated by th e Polish Air Force. No te the black anti-glare pan els on the wingtip tanks.

( JJ i lj sk Ol ra

A gcnc]« Fotograficzna )

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Close-up of th e wingtip drop tan ks o n the same ai rcraft. 03 Red; the d rop tan ks were the chief recognition feature of the reconnaissa nce version. ( JJ i i jskOl ra A •~"!lci(/ J • FOlo~rafiC=!I(/ •• •

32 • I LYUSHIN I L- 28 BE.IGI.E

seconds - much faste r than on the sta nda rd bomber. T he higher gross weight of the Il-28R a lso led the designers to introduce a unique feature minimizing wear and tear on the tyres: the mainwheels were spun up a utomat ically by hyd raulic mot ors when the gear was extended . Acco rdi ng to the crews. this resu lted in a n exceptio na lly smooth touchdown. Owing to the inst allation of ca mera controls the starboard fixed R-23 ca nnon had to be deleted as a weight-savin g measure. The PSB N-M rad ar was some times removed as well: in that case 11 0 kg ('42 .5 lb ) of ball ast was ca rried in th e navigat or's co mpa rt ment for C G reason s. Some changes were made to th e avionics fit: th e reconnaissance versio n featured a Magniy-M (Magnesium-M) IFF interrogator. an RSB-5 communications radio with a US-P receiver. an RSI U-3 command radio. an SP U-5 intercom. RV-2 and RV-IO radi o altimeters. an SP-50 Mat erik ILS. etc. For overwater Iliahts the Il-28R co uld carry an LAS-3 inllatable rescue dinghy ilodka avareeyno-spasahtel'ua va i in the bom b bay: thi s could be d ropped by either the pilot or the gunner a nd inflat ed a uto ma tically by a rip cord . The perfo rma nce of the Il-28R was broadly ~

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sim ila r to that of the basic bomber. except that range in hiuh-altit ude cruise increased to 3. 150 km ( \. 702 nrn): the combat radius 740 km (400 nrn ) at 5.000 m (1 6.404 ft) and 1.140 km (6 16 nm ) a t 10.000 m (32.808 tt). Indicated airspeed was limited to 750 km/h (41 6 kt ) at up to 4.000 m ( 13. 123 ft), a nd M ach 0. 78 above that a lt itude. Kokkinaki reported th at handling a nd cock pit visibility remained unch anged . High-speed aeria l phot ography at va rio us a lt itudes did not affect piloting techniques. The a uto pilo t. as well as the heated a nd pressurized cockpits. reduced crew fatigu e. wh ich is especially important for a reconnaissance aircraft. Initial flight testing was completed o n 29 June 1950. After pa ssing the State acceptance trial s o n 23 N ovember. the 11-28R wa s ordered int o production on 8 December 1951 and joined the VVS invent ory. Initially the reconnaissance versio n wa s built in M oscow. but from 1953 onward s 11-28R production wa s passed on to aircraft fact ory N o. 39 in Irkutsk. which had previ ously built the Tu-14T. The performance o f the production 11-28 a nd 11-28R is compared in Table 6. ~

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The field performance of the bomber and reconnai ssance versions is compared in Tabl e 7.

Table 6. Performance comparison: production 11-28 and I1-28R 11-28

I1-28R

Empty weight. kg (lb)

12.720 (' 8.0·P)

13.250 (29.21 0)

All-up weight. kg (lb): normal in overload co nfigura tio n

18.-100 (40.564) ,),,'.000 (48.500)

20.020 (44.135) 22.-190 (49.58 I)

Fuel capacity. lit. (imp. gal .)

8.00D( 1.760)

9.550 (' .101)

Top speed. km/h (kt) at altitude. m ( ft)

902 (487) 4.500 ( 14.763)

876 (473) 5.000 ( 16.404)*

Service ceiling. m (ft)

12.-100 (40.682)

12.300 (40.354)

Time to service ceiling. min

37

42

Range. krn (miles): at 5.000 m ( 16.404 ft) cruising at. km/h (kt) at 10.000 m (32.808 ft) crui sing at. krn/h (kt) at 10.000 m (3"' .808 ft) cruising at. krn/h (kt)

1.790 (1.1 II ) 556 (300 ) 2.450 ( 1.52 1) 698(377) 2.580 ( 1.6(2 ) 690 (373)

' .0'0 ( 1.242) 547 (295) 2.780 ( 1.726) 670 (362) 3.040 ( 1.888 ) 670 (362)

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Note: * The 11-' 8R's indicated airspeed below 4.000 m (1 3.1'3 It) was limit ed to 750 km/h (405 kt): the Mach limit above 4.000 III was 0.78.

TH E

IL-28 FA ~II LY • 33

Table 7. Comparison of field performance: bomber and reconnaissance versions TOW. kg .n»

Unstick speed. krn/h (kt)

Take-otT run. 111 (ft)

Landing speed, krn/h (kt )

Landing run. m (ft)

240 (129)

IAOO(4.593)

1.500 (4.921 )

19.800/22.200

259/"174

1.61 012.1 50

(43.650/48.94 1)

( 1401148)

(5.282/7.053)

200- 205 (108- 110 ) 220-225 ( I 19-1 21 )

240 ( I"19)

1.700 (5.577)

l.200 (3.93 7)

19.800/22. "100

2591274

1.72012.300

(43.650/48.941 )

(14011 48 )

(5.643/7 .546)

200-205 (1 08-11 0) 220-225 (119-1 "II )

a) paved ru nway 20.1 00 (44.3 P) 11-28 11-28R

b) unpaved run way (dirt strip) 20. 100 (44.312 ) 11-28 11-"I 8R

1.620 (5.315)

1.300 (4.265)

I1-28RTR ELINT aircraft

I1-28REB (?) EClVl aircraft

Apart fro m the IJ-28R PH OTI NT aircra ft. the Beagle a lso had an electronic intelligence (E LINT) versio n designated IJ -28RTR ( [salllo~ro t] rahdiotek hnicheskoy raz vedki i reconnaissance aircra ft powered by VK- I engines. Outwardly it co uld be identified by a second tea rdrop-shaped dielectric fairing ins talled in lieu of the faired -over bomb bay doors, T he IJ-28RTR was supplied to both the VVS and the a ir fo rces of some of the Soviet Union's allies. including Czechoslovak ia and Hunga ry.

Another specialized version was intended for electronic co untermeasures (ECM) . Some sources claim the aircraft was designated I1-28REB (rahdioelek tronnava bor 'bah - ECM). The main identification feature of thi s version was the cylind rica l wingtip pods reminiscent of the I1-28R 's d rop tanks, but feat uri ng dielectric front and rear po rtions co ncealing emitter antenna s, The ECM versio n was also supplied to Czechoslovakia .

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A Hu ngarian Air Force 11-28RTR ELINT aircraft . showing clearly the dielectric teardrop fairing over ELI NT equipment aft of the sta nda rd rad ome. ( } :> 21. 545 21. 61 6 21 .82 5 21. 094 2 1.325 21.626 2 1.57 5 21.640 -"1 .8'- :>(4 7.564 ) (47.707 ) (47.5 64 ) (47.497 ) (47.654 ) (48 . 115) (46.503 ) (47 .0 12) (47 .676 ) (48 .1 15)

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8 January 1951 with Vladimir K. Kokkinaki at the con trols: N . O. So rokin was the !light engineer and A. P. Vinozra dov was the engineer in cha rge o f the !light tests. The second prototype (c/n 5030 II 04) joined the p rogramme on 12 March 1951, making its m aiden flight from Khodynka - again at the hands of Vlad im ir K . Kokkinaki, O utwa rd ly the I1-2 8T p rototypes ditTered from sta nda rd Beagles in having a small Perspex blister under the nose accom modatin g the lower part o f the PTN -45 sight, a non-st andard navigat or's glazing framework and a non-stand ard angular cockpit windsh ield with a rectangula r windscreen a nd op tically nat sidelights. The m anufa cturer's tests were completed on 17 April 1951 (the test report was endo rsed six days la ter). Then the I1-28T was submitted to the Soviet Navy's Research Institute N o. 15 for State accepta nce trials. which proceeded from 7 June to 25 July 1951 and a lso went successfu lly. In Augus t 1951 the com plete set of m anufacturing d ocuments was tra nsferred to one of the p roduction factories: the type en tered limited production and service wit h th e AVMF." For this achievement a grou p of O K B-240 employees was aga in nominated for the Stalin Prize. The specificatio ns of the I1-28T are given in Table 8. ~

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Tables 9 a nd 10 detail the II-1ST's weapo ns op tions.

the AVM F arsenal. fo llowed by the 45-56NT torpedo two yea rs later. Both types were powered by steam engines a nd were ca rried by th e Tu- 14T along with the R AT-52. In orde r to standa rdize the armament carried by Soviet to rpedo-bombers and increase their punch , it was decided to upgrade the 11-28s then in service. To this end a sta nda rd 11-28 torpedo bomber was ret rofitted with two exte rna l BOAT to rpedo racks (bahlochnyy derzhahtel' - bea m-type [weapons] rack ). The increased payload meant that the centre fu selage frames had to be rein forced. The aircraft was also fitted with the new PTN-5 5 low-altitude sight, albeit incomplete. which was concurrent ly being tested o n a mod ifi ed Tu-1 4T T his allowed the navigator to programme the to rped o to move in a zigzag (t his feature was believed to increase kill p robability but demanded a substa ntia l increase in the torpedo 's range) and feed ta rget data into the torped o's con trol m odule up to the m oment of release. The modi fi ed a ircraft - which. ra ther confusingly. was again designated 11-28T - could carry three R AT-52 torpedoes (two externa lly and one internall y) or two 45-54VT or 45-36NT to rpedoes externally: alternatively, two AM O-500 anti -shipping mines co uld be carried externally. The weapon s were dropped at altitudes of 40-400 m ( 13 1-1.3 12 It ) a nd speeds of 360-800 kmlh (200-444 kt). H owever. the Navy was displeased. claiming the ~

I1-28T torpedo-bomber conversion (second use of designation) In 1954 the improved 45- 54VT torpedo (i.e. 450 mrn calibre. 1954 m odel. VT = vysotnove torpedometahniye - high-altitude torpedo attack) was included in

6 So me sources. though. claim th e 11-' ST did not enter production beca use of the protracted de velopment o f th e 45-56NT torpedo and the inability to ca rry two RAT-52 torped oes in ternallv. •

.to . ILYUSHI NIL-2S B EAGLE req uired modificati ons were too extensive. Besides. the high-drag external sto res impaired the aircraft 's performa nce and ca used some restrictions on piloting techni ques. Rotati on at take-off became very diffic ult: the aircraft experienced severe vibration at high speed. almost cert ainly ca used by the turbulence generated by the external torpedo racks. Tailplane buffet was commonly encountered in a sha llow dive when two torpedoes were carried externally: if o ne torpedo was ca rried it generated so much d rag as to render turns in the o pposite direction impossible. The a ircra ft completed its trials programme in 1955 . All its shortcomin -gs notwithstanding. the Navy expected to modify so me o f its 11-28s to this standa rd. However. this conversion programme never materialized because the 11-28 was ge tting long in the tooth and the Soviet bo mbe r and torpedo-bomber force was re-eq uipping wi th the more modern Tu-1 6. Sti ll. the PT N-55 sight did find its way• int o service. ~

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This Beag/e. with a non-standard deep radorne and d rop tank s. is probably an 11-' SN (1I-2SA) nuclear-capable bomber. ( Ycfin, G"rd"" " rehire!

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Il-28N (1I-28A) nuclear-capable bomber

d ropped , with a day's interval in each case. between 29 Septem ber and 5 Octo ber 1954. A ll in all the test progra m me involved more th an fift y flight s. fifteen of which were weapon drops: the sa fety of landing wit h an unused bomb was checked. among other thi ngs. After the successful completion o f the trials the R O S-4 entered production: so did the nuclear-capable version of the Beagle, which was designated 11-28 tnositel' [spetsboy ep ripallsa] - ca rrier o f special. i.e. nuclear. munitions). A pa rt from the changes to the bomb bav, the aircraft differed from the sta nda rd bomber in having an updated avio nics suite. T he PSB N-M ground -mapping radar was replaced by an R BP-3 unit truhdiolokatseeonnvy bomburdirovochnyv pritsel >- radar bomb sigh t) in a muc h deeper radome.' It indicated headings. di sta nce to gro und waypoin ts, altitude above such waypo ints. gro und speed a nd aircraft po sit ion. The bomb bay was provided with a heating system to keep the nuclear bom b's systems fro m freezing up. a nd the cockpits fea t ured shutters protecting the crew from the fl ash of the nuclear explosion. An R SI U-5V U H F comm unications radi o. a US-8 receiver. a nd RV-1 8 and RV-2 rad io altimeters were fitted . The electrical system was modified to include PO-3000 (ma in) and PO- 3000A (reserve) singlephase AC transformers, The 11-28N 's empty weight was 13.040 kg (28.747 lb). - 150 kg (330 Ib ) more than the sta nd a rd bomber's: TOW was 18.550 kg (40. 895 Ib). The C G had shifted sligh tly aft. but thi s had virt ua lly no effect on the aircraft's hand ling and performance. Fort y-two 11-28N s were briefly deployed to C u ba in 1962 during the Cuban missile crisis, This versio n is sometimes referred to as 11-28A (uhtotnnyv at omic. i.e. nuclear-capable). ~

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The Soviet military d octrine of the early 1950s • • dema nded that tactical aviation was to possess nuclear ca pability. Several types o f small tactical nuclea r weapons. including the ROSA Tatyana bomb. were under development at the time. and the Soviet govern ment issued a directive demanding the developme nt of new tactical bombers capable of delivering them. H owever. this wo uld clearly . be a time-consuming process. so it was decided to modify existing a ircra ft in service with the VVS. incl uding the 11-28. for the nuclear role. First. two 11-28s were specia lly modified by O K B-30 (the design bureau o f MMZ No. 30). fo r testing the ROS-4 according to the specifications passed by OKB-I I. which had developed the bomb. Among other things. the modification involved heat insulation and heating of the bomb bay. . installation of special equipment to mo nitor the weapon's systems status. as well as test equipment to measure the parameters o f the explosi o n. includ ing cine-ca meras capturing the development of the famo us mush room cloud. The first d rop of an ROSA from the 11-28 took place on 23 Augus t 1953. On that occasion the bo mb was in the so-ca lled check configuration with data link sensors and a conventiona l warhead. T he aircraft was fl own by pilot V. I. Shapovalov, navigator/bom b aimer A. V. Koz'minykh and gunner/rad io operator B. S. Soodakov. The weapon was d ropped at 11 .000 m (36.089 It), det onating successfully at the preset altitude. Four ROS-4 bombs were ~

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TH E IL-28 FAMILY

I1-28S tactical bomber project In 1949-50 OKB-240 so ught ways of further improving the design of the basic 11-2.8. The main objective was to increase the bomber. s speed ~nd ran ge. This was to be achieved by matrng the existing ~fuselage and tail surfaces with all-new wings swept back 35° at quarter-chord and installing m.ore powerful and fuel-efficient Klim ov V~-5 .centrIfugal-flow turbojets. The VK-5 was a derivative of the prod uction VK- IA uprated to 3.\00 kgp (6. 834. Ib st) for ta ke-off and 2.760 kgp (6.084 Ib st ) for cruise. differing mainly in having a more effi cient compressor: the'engine's dry weight and external dimensions rema ined unchanged. This undoubted achievement was made possible by the use of new heat-resistant alloys. a higher turbine temperature ~lI1d .more efficient cooling. Specific fu el consumption (SFC) was 6 per cent lower than that of the production VK- IA. However. preliminary design studies showed that the swept-wing Il-28S tstrelovidnove krvlo - swept wi ngs) o ffe red no significa nt ad vant ages over the prod uction Beagle. Mo reover. the incorp? ration of new wings would incur major technological problems. Hence development of the Il-28S was abando ned - a decision later proved co rrect by the chief co mpetito r's negative experience. The Tupol~v 0 KB had achieved sca nt success with the experimental 7 Some sources cla im the I1 -2SN was o utwa rd ly identi cal to the sta nda rd bomber.

'aircraft 82" (Tu-82) swept-wing tactical bomber (which. incide nta lly. closely resembled the would-be II-28S).

I1-28RlVI experimental tactical reconnaissance aircraft Meanwhile. the Ilyushin OK B attemp ted to introduce the new VK-5 powerp lant on production versions of the straight-wing 11-28. Several government . . directives and MAP orders were issued. envisaging the installation of VK-5s on all three principal versions of the Beagle - conven tiona l bomber. torpedo-bomber and recon na issanc~ airc raft.. . The last version received the highest pnoruy, since the VVS was desperate to extend the reach of its tactical reconnai ssance aircraft. The PH OTI NT aircraft then under development at the Mikoyan (OKB-155) and Ya kovlev (O K B- 115) design bureaux were a priori handicapped by inadequate range. being derived from tactical fighters: conversely, the 11-28R a nd 'aircraft 78' (Tu-78. the PH OTI T version of the Tu-14) were based on bombers desi gned to have much longer range. The 3.000 km ( 1.863 mile) ra nge target was to be met by installing more fuel-efficient engines. On 3 August 1951 the Council of Ministers iss ued directive No. 281 7-1 388ss. ordering the development of the 11-28RM ( [SW IIO ( l'o t - ] raz vedchik. modifitseerovannvv - reconn ai ssance aircraft. modified) powered by VK-5 engines. The dead line for submission for State acceptance trials was set at ~

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The 11- "'l8 RM proto type: no te the a ngula r cock pit winds hield.

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( },:f im Gordon archive}

42 • ILYUSHI N IL-28 B EAGLE

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T he same ai rcra ft with th e drop tanks rem oved, revea ling the vertica lly cut-otT wingtips with drop tank fittings instead of the usual wi ng tip fairings. ( Ycf in: Gordon arch i vc)

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-- - Head-o n view of the Il-28R M. ( l i:/;III Gordon ar..hive}

TH E I L-2 8 FAMILY • ~3

Table I I. 11-28Ri\I specifications Ma nufacturer's fli ght tests

Length overall Heigh t on ground Span Wing area Wing loading. kg/m' (lb/ff ') Power loading at sea level. kglkgp (lbllb st ) Operating empty weight. kg (Ib) No rma l all-up weight. kg (lb) Maximum AUW (with drop tanks). kg (lb ) Fuel load. kg (lb): internal with drop tanks Payload. kg (Ib) : normal in overload co nfiguration (with drop tanks) Top speed. krn/h (kt): at 4.250 m ( 13.943 ft) ~

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at 5.000 rn ( 16,404 ft) at 6.600 m (2 1.653 ft) at 7.000 m (22.965 ft) at 10.000 m (32.808 It) Rate of cl imb. m/sec (ft/min): at sea level at 5.000 m (16.404 ft) at 10.000 m (32.808 ft) Climb ti me. min : to 5.000 m ( 16,404 ft ) to 10.000 m (32.808 ft ) Service ceiling. m (ft)

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Range without drop ta nk separatio n. km (miles) Range with drop tank separation. km (m iles) Endurance wi tho ut drop tan k sepa ration End ura nce with drop tank sepa ration Take-o lT run . m (ft) Take-otT distance. m (ft)

State acceptance trials

17.65 m (57 ft 10. 88 in.) 6.0 m ( 19 ft 8.22 in.) 21,45 m (70 ft 4,48 in.) 60.8 nr' (653.76 sq. It) 321 (1.560) n.a. n.a. 3.12 13,485 (29. 728) 13.467 (29.689) ")0.200 (44.532) 19.500 (42.989) 22.950 (50.595) 22.930 (50. 551 ) 5.030 (11.089) 8.250 (18. 187)

5.030 (11.089) 8.")00 (1 8.077)

6.0 15 (13.260) 9.467 (20.870)

6.0 15 (13.260)

926/n.a. (500.54/n.a. )* 877185 1 (474.0/460.0)** n.a .

n.a.

n.a. 862/827 (465.94/447.0)** 24.5/1 7. 0 (4.8") 1/3.345)** 15.4/1 0.3 (3.030/2.027 )** 6.6/3 ,4 (1.299/669)** 4.2/6.15 ** 12,4/9.3** 13.050/1") .1 75 (42.8 14/39.944)** 3.007 (1.867) # 3.042/3.254 ( 1.889/") .0") I ) t 4 hr40 min # 4 hr 39. 5 min/ 4 hr 49.5 min t 963/1.233 (3. 159/4.045) tt 1.807/").477 (5.928/8 .1 26) It

n.a .

n.a . 89 1/863 (481.6")/466,48)** n.a./863 (n. a ./466.48)** n.a./841 (n.a./454.59)** n.a .

n.a. n.a. 6.2/n.a .** I 8.0/n.a.** 12.500/1 1.500 (41.0 I0/3 7.729 )** 2.090 ( 1.298) ## 3.250 (2.01 8) t n.a. n.a.

995/1.295 (3.264/4.248) tt 2.030/2.400 (6.660/7.874) tt

Notes:

At ta ke-off power (N = 11 .560 rpm) : other data fo r N = 11 .200 rpm . With normal/maximum AU W - 19.700/22. 570 kg (43.430/49.75 7Ib ) respectively du ring manufactu rer's fl ight tests and 20.200/22.930 kg (44.532/50.551 lb) respectively during St ate acceptance trials. # TOW 23.000 kg (50.705 Ib ). cruise alt itude 10.000 m (32.808 ft) and cruising speed 670 km/h (362.16 kt). ## TOW 22.930 kg (50.55 1 lb), cruise alt itude 5.000 m (16.404 It) and cruising speed 560 km/h (302.7 kt). TOW 23.000 kg (50.705 Ib ). cruise altit ude 10.000/1 0.500- 12.500 m (32.808/34.448- 41.0 io n: and cruising speed t 68 ")/695 km/h (368 .64/375 .67 kt) respectively. tt With normal/max imum TOW respectively. + At opti mum cruise altitude and cruising speed 665 km/h (359 ,45 kt). + * **

...... ILYUSHI N I L-2 8 S E. IGLE

Ta ble 12. 11-28 " K-5-powered prototype specifications Manufacturer's flight tests c1n 52003701 c/n 52003719

Lenut h overaII Spa n Wine area Winu loudinu. h im' (lb/ft") Power load ing at sea level. kglkgp (lb/lb st ) Operating empty weight. kg tlb) Normal all-up weight. kg (lb) Maximum AUW (with drop tanks). kg (lb) Fuel load. k c (lb): internal with drop tanks Payload. kg (Ib): normal • maXIl11Um Top speed at 19.300 kg (42.5"'8 n» AUW and N = 11.560 rpm. km/h (kt l: at SIL at 2.850 m (11.653 It ) at 3.000 m (22.965 ft) at ·tOOOm (13.943 ft ) at 5.000 m ( 16.404 ft ) at 10.000 m (32.808 ft) Landing speed. kmlh ( k t) Rate of climb at 19.300 kz (41.548 lb) AU W and = 11 .250 rpm. mlsec (ft/rnin j: at sea level at 5.000 m at 10.000 m Climb time at 19.300 kg AU W and = 11. 150 rpm. min : to 5.000 m to 10.000 m Effective range with d rop tanks and 2.000 kg (4.409 Ib ) of bombs. krn (miles) Technical range with drop tanks and 1.000 kg of bombs. km (miles) Technica l range with out drop ta nks and with 1.000 ku (2.204 lbj of bombs. km (miles) Endurance with drop ta nks and 2.000 kg of bombs Endurance witho ut drop tanks and with 1.000 kg of bombs Take-off run. m (ft): with normal TOW with maximum TOW Take-off distance. m (ft ): with norm al TOW with ma ximum TOW Landing run . m (It): no a irbrakes airbrakes deployed Landing di stance. m (ft) : no a irbrakes airbrakes and brake parachute deployed

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S tate acceptance trials c/n 52003701

c/n 520lJ371 9

308 (1 .496) 3.2 13.350 (19.43 1) 18.710 (41.24 7) 24.090 (53. 108)

17.65 m (57 ft 10.88 in.) 21.45 m (70 ft 4.48 in.) 60.8 m' (653.76 sq. ft) 311 (1.5 11) 322 (1.565 ) 3.2 3.1 6 13.560 (19.894) 13,113 (28.908) 18.920 (41.7 10) 19.600 (43 .209) 24,300 (53.571) 24.050 (53.020)

13.365 (29.464) 19.850 (43 .761 ) 11 14 -~~ 9­ - .-- 0 (:>... :»

3.800 (8.377) 8.000 ( 17.636 )

3.800 (8.377) 8.000 ( 17.636)

3.800 (8.3 77) 8. 150 (17 .967)

3.800 (8.377) 8.050 ( 17.746)

5.360 ( 1l.8 16) 10.740 (23.677 )

4.360 (9 .6 12) In.740 (23 .677)

6.487 ( 14.30 I ) 6,485 (14.296) 10.837 (23.89 1) 10.855 (23.930)

800 (432.43)* 9 17 (495.67) n.a. n.a. 900 (486.48) 828 (447.56 ) 189 (102)

800 (432.43 )* 9 18 (496. 21 ) 921 (497. 83) 9 18 (496. 11 ) n.a. 186 (100.5)

800 (432.43)* n.a. 9 11 (492.43) n.a. n.a. 844 (456.2 1) n.a.

800 (432.43) * n.a. 900 (486.48) n.a. n.a. 844 (456.21 ) n.a .

21.5 (4.231) 13.9 (2.735) 6. 5 (1. 1 79)

19.5 (3.837) 13. 1 (2.5 78) 6.75 ( 1.328 )

n.a . n.a. n.a.

n.a. n.a . n.a .

4.85 13.3 3.000 ( 1.863)

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13.8 3.000 ( 1.863)

n.a . 14.0 2.710 (1.683)

n.a . 14.0 2.670 ( 1.658)

3. 100 ( 1.915) *

3.0 11 ( 1.870) **

1.298 (806)***

1.309 ( 1.870)

1.820/3.020 # ( 1.75 1/1.870) n.a.

2.790/2. 980 ## ( 1.7 33/1. 850 ) n.a .

4 hr 33 min **

n. a.

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t

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n.a .

r.ooo (3.280)

lUI.

316 ( 1.584) .~ .-1

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4 hr 51 min* 1 hr 07 min ***

2 hI' 02 min

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920 (3.0 18) 1.41 0 (4.6 16) t

945 (3. 1no) 1.430 (4.69 1) tt

1.370 (4.494)

1.050 (3.444) 1.360 (4,461)

1.875 (6. 15 1) 1-.:>_:> '1- ( 8.-18'.. ) -'I-

1.000 (6.56 1) 1.708 (8.884) tt

1.760 (5 .774) 1.4 15 (7.923)

1.954 (6.41 0) 2.345 (7.693)

9 13 (2.995) 607 (1.991)

n.a. 524(1.71 9)

660 (1.165) 550 ( 1.8(4)

800 (2.624) 660 (2. 165)

1.692 (5 .55 1) 1.255 (4.11 7)

n.a. (3,6 18)

n.a. n.a.

n.a . n.a .

TH E

March 1952 - a tigh t sched u le which p roved impossible to mainta in . The unseriall ed I1-28 R M pro totype (c/n 520037 14) first flew o n 17 February 1952. but the manu fa cturer's flight tests were not com pleted until 12 Ap ril (the test report was signed o n 29 April); thus the State acceptance tria ls did not com mence until 10 July. The tria ls were du ly completed o n 15 January 195 3. The I1-28R M featured the latest version of the intended powerplant - the VK -5E (ekonomichnyy fuel-efficient), incorporating additional measures aimed at reducing the SFC. This engine passed its State acceptance tria ls conc urren tly with the a ircraft itself. T he new engines necessitated a redesign of the engine bearers a nd engine nacelle structure. the engine control system had to be modified and the lower skins of the o ute r wings stiffe ned. N o changes were made to the a rmament a nd eq uipmen t. Nevertheless. the good performance of the aircraft a nd its powerpla nt did not help. Because of the scrapping o f the I1-28S a nd Tu-93 projects for which the new engine was prima r ily intended (the Tu-93 was a V K -5 powered version of the Tu-14 ). the VK -5 did not en ter prod uct io n - a nd hence neither did the I1-28R M. Besides. it was clear by then that axial-flow turbojets we re superio r to cen trifugalflow engines. The specifica tio ns of the Il-28RM are detai led in Table II .

IL-28 FA ~IILY • ~5

11-28 experimental tactical bomber with VK-5 engines

engi ned bomber variant was initiated by Council of M inisters (CofM) directive o. 5329-2088ss of 29 D ecember 1952 and MA P order No.lss of I January 1953. The two prot otypes were converted from standard M oscow-built Il-28s (c/ns 5200370 I a nd 5200371 9) . Pursuant to the above-mentio ned Co lM directive the first p ro to type was to be transfe rred to LI I for testing. while the ot her a ircraft was to be delivered to N Il VVS in Apri l 1953 for State accepta nce trial s. Apart fro m the engines. the bombers had a few o ther changes. Bo th aircraft had wings taken from the Il-28R. with wingtip d ro p tanks to extend their range. The seco nd proto type feat ured enlarged 1,260 x 390 mm (49 .6 x 15.35 in .) mainwheel s borrowed from the Il-28R and a n a uto matic wheelbrake system. while the first pro to type ret a ined sta nda rd 1.150 x 355 mm (45.27 x 13.97 in . ) ma inwheels. The 12-A-30 D C batteries were replaced by new 12SAM-25 bat teries and moved forward to the radar bay to shift the CG forward. The defen sive armament was identical to that of the standard Il-28. comprising two nose-mounted R-23s with 100 rpg and two N R -23s with 225 rpg in the tail turret. The norma l bomb load and the maximum bomb load were 1.000 kg (2. 204 lb) and 2.000 kg (4.409 Ib ) respectively. Both aircraft we re com p leted within a sho rt timescale and dul y tested: the ma nu facturer's flight tests report was endo rsed on 28 Apri l 1953. and the State accep tance trial s report exactly three months later. The specifications of the VK-5-powered bomber prototypes are given in Table 12.

The next version of the Beagle to be powered by VK-5s was the regular bom ber. Logically th is ai rcraft shou ld have been design ated II-28M . but no separate designatio n was a llocated for some reason. and the designati on II-28M was eventua lly used for ano the r vers ion (see below) . D evel opment o f the re-

On 10 Se ptember 1953 II VVS concluded that it wo uld be a dvisable to lau nch series production of the VK -5-powered I1-28. H owever. the upgraded bomber did not ente r production for the reasons sta ted above.

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Notes to Table 12: * TOW , ·t 170 kg (53 .'84 Ib l. cruising speed 650 krn/h (35 1.3 kt) and cruise a ltitude (34,448-43.307 ft l. ** TOW 2·+.330 kg (53.637 lb). cruisi ng speed 680 krn/h (367.5 kt) and cruise altitude (34,448-42.979 ft). *** TOW 18.710 kg (4\.247Ib). cruising speed 650 krn/h (351.3 kt) and cruise a ltitude + TOW 18.920 kg H 1,71 0 lb). cruising speed 700 km/h (378.3 kt) a nd cruise altitude + # TOW ' 4.050 kg (53.020 lb ), cruising speed 668 krn/h (36 1.0 kt) and cruise a ltitude (32.808/32.808-39.370 ft ). ## TOW 24.220 kg (53.395 Ib ). cru ising speed 668 km/h (361 .0 kt jand cruise a ltitude (32.808/32.808-39.3 70 ft ). t TOW '3.800 kg (52,469 Ib). tt TOW 24.000 kg (52.9 10 n».

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10.500-13.200 m 10.500-13.1 00 m 10.000 m (32.808 ft). 10.000 m (32.808 ft). 10.000 m/lO.000- 12.000 m 10.000 m/l O.000-1 2.000 111

46 ' ILYUSHIN IL-28 B EAGLE

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... Red. the I1-28TM torpedo-bomber prototype. photographed d uri ng trials in 1953. t Ycfitn Gonlon archive )

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Ano ther view of the I1-28TM; the c/n 5030 1106 reveal s the aircra ft was converted fro m the first prototype I1-"' 8T. ( Ycfin: Gordoll archive j

I1-28TM experimental torpedo-bomber The I1-28TM torpedo-bomber (to rpedonosets modifitseerovannyyi was the last of the three Beagle variants modified to take the VK-5 engine. It was developed in accordance with CofM d irective No. 721 8rs of 22 May 1953 and Ministry of Defence Industry (MOP - Ministerstvo OhOl'0I1110y promyshlennostii order No. 295ss of 27 May. The schedule stipulated by the government was extremely tight: the prototype was to be handed over to the Navy's Research Institute No. 15 in just one month . In those days it was customary in the Soviet Union to strictly comply with government orders and directives concerning the defence industry. ~

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whateve r the cost. O K B-240 man aged to complete the prot otype within the stated timescale by converting one of the I1-28T prototypes (c/n 5030 1106).' The installatio n of VK-5 engines with new extension jetpipes led to several associated changes. The front parts (detachable engine cowl ingsjand rear pa rt s of the nacelles were modified. th~ electric wiri ng inside the nacelles was rerouted a nd the engine coo ling d ucts were modified. Changes were a lso made to the engine controls. a ~

8 The c/n shows that the aircraft was built in 1950. so thi s was probably a development aircraft retained by the Ilyushin OKB.

TH E

IL-2 8 FAMILY• ~ 7

Ta ble l2a. 11-28TM weapon configuration ormal wea pons load

Total weight.

M ax imum weapons load

kg (Ib)

2 x FAB-500M -46 bombs I x 45-36AMV torpedo 1 x 45-36AMN torpedo 1 x RDT torpedo 2 x AMD-500 mines 1 x AMD-IOOO mine 1 x Lira mine I x Desna mine

1.000 (2.204) 1.073 (2.365) 1.030 (2.270) 615 (l.355) 1.0 18 (2.244) 1.01 8 (2.244) 988 (l.l78) 768 (1.693)

Total weight. kg (Ib)

12 x OFA B- IOO bombs 8 x FAB-250M-46 bombs 4 x FA B-500M-46 bo mbs I x FA B-1500M -46 bomb I x FA B-3000M -46 bomb I x TAS torpedo 1 x TAV torpedo 4 x AMD-500 mines 1 x AMD-M mine I x Serpey mine 2 x 45-36AMV torpedoes ') x Lira mines 2 x Serpey mines 2 x Desna mines

new fire-extinguishing system was insta lled and the engines' foreign object damage (FOD) protection screens. made of wire mesh. were provided with a de-icing system . In additi on. a seventh fuel cell (No. 3B) was fit ted. drop tanks were installed at the wingtips and the liquid oxygen bottles were relocated. T he higher gross weight required the standard mai nwheels to be replaced with \.260 x 390 mm (49.6 x 15. 35 in.) mainwheels. as on the I1 -28R. Finally, a second nose cannon with 100 ro unds was installed o n the sta rboard side (as a lready mentioned. the prod uction I1-28T had o nly the portside forward -firing cann on). Table 12a shows the I1-28TM's weapons configurations. Serialled 4 Red. the aircraft completed its manu-

l.200 (2.645) 2.000 (4.409) 2.000 (4.409) 1.5000.306) 3.000 (6. 613) 1.520 (3.350) 1.283 (2. 828) 2.01 8 (4.448) 1.1 88 (2.619) 1.268 (2.795) 2.128 (4.691 ) 1.958 (4.31 6) 2.51 8 (5 .551) 1.51 8 (3.346)

facturers night tests by late June 1953 (the test report was signed o n 30 June) and passed State acceptance trials in July (the Soviet avy's Research Institute N o. 15 issued its act of accepta nce on I August). Still, the I1-28TM fared no better that its comrades-in-engines. i.e. the o the r versions sha ring the VK -5 powerplant. The specifications of the I1-28T M prototype are given in Table 13.

11-28-131 guided bomb carrier Back in the early 1950s the Soviet Union sta rted experimenting with precision guided munitions (PGM s). An experimental bat ch of U B-2000F radio-controlled guided bombs (U B oopra vlyayemaya bomba - guided bomb ) was built ~

An 11-28-131 with a UB-2F Chaika guided bomb suspended under the fu selage. ( I e/1m Gordon archive}

48 • ILYUSHI NIL-28 B EAGl. E Table 13. I1-28TM prototype specifications Manufacturer's fli ght tests

Lenuth overall b Span Wing area Wing loading, kg/nf (Ib/ff') Power loading at sea level. kg/kgp (lb/lb st) Operating empty weight. kg (lb) Norma l all-up weight, kg (lb) Maximum AU W (with drop tanks). kg (Ib) Maximum AUW (with drop tanks and PSR-1500-15 JATO bottles), kg (lb) Fuel load , kg (Ib): internal with d rop tanks

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State acceptance tria ls

17.65m (57ft 10.88 in.) 11A5 m (70 ft 4A8 in.) 60.8 m' (653 .76 sq . ft) 380( 1,846) 366(1, 778) 3.3 3.56 13.395 (29,530) 13,395 (29.530) 18.790 (4 1,424) 18,788 (41,41 9) 22,070 (48,655) 22,068 (48.650) 22,550 (49,7 13)

n.a.

3,800 (8,377) 6.880 (1 5,167)

3,800 (8.377) 6,880 ( 15,167)

5.397 ( I 1,898) 8.675 (19,124)

5,383 ( 11,867) 8,663 (19.098)

800 (432.43)* 90 1 (487.0) 836 (45 1.89) 188.5 ( 10 1.9)

800 (432.43) * 895 (483. 78) 83 7 (452.43) 178 (96.2)**

15.4 (3.030) 11 .22 (2,208) 6.85 (1,348)

16. 3 (3 ,207) 9.3 (1.830) 4.0 (787)

6.36 6.85 2, 172 (1,349)

6.6 19.5 2,166 ( 1,345)

2,326 ( 1,444)

2.3 15 (1,437)

2,499 (1 .552)

n.a .

3 hr 48 min

3 hr 41 min

4 hr 20 min

n .a.

1.090 (3.576) 2,055 (6.742 ) 890 (2,920) 1.5 10 (4,954)

I, 160 (4.1 33)

Pavload, kg . _(Ib .):

normal maximum Top speed at 22.070 kg (48,655 TOW and take-off power rating. krn/h (kt): at sea level at 5,000 m (1 6,404 ft) at 10.000 m (32,808 It) Landing speed. km/h (k t) Rate of climb at 22.070 kg TOW and cruise power rating, m/sec (It/min): at sea level at 5,000 m ( 16,404 ro 10.000 m (32,808 ft ) Climb time at 22.070 kg TOW and cruise power • rannu. nun: to 5,000 m ( 16,404 ft ) to 10.000 m (32,808 ft) Effec tive range at 10,000 m with drop tanks and 45-36AM Y torpedo. krn (m iles) Technical range at 10.000 m/600 km/h (324 kt) with drop tanks and 45-36AMY torpedo, km (miles) Technical range at 10,400-12,550 m (34.120-41,174 ft)/ 585- 900 km/h (316-486 kt) with drop tanks and 45-36AMY torpedo. km (m iles) End urance at 10,000 m with drop tanks and 45-36AMY torpedo Endurance at IOAOO-12,550 m/585- 900 km/h with drop tanks and 45-36AM Y torpedo Take-off run at ma ximum TOW. m (It) Ta ke-off distance at ma ximum TOW. m (1'1) Landing run. m (ft ) Landing distance. m (It) •

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Notes: * Speed limited because of dynamic strengt h limit. ** Data for YK-I-powered I1-28T. *** Data for YK-I -powered I1-28T with a 15.000 kg (33,068 Ib) landi ng weight.

2,025 (6.643) 940 (3,084) *** 2.125 (6,971) ***

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Above: Thi s head -on view of an Il-28U shows how the train er provided both pilot s with an unrestricted forward view. ( RA R T)

Above: Il-28 01 Red (em 36603807) is part of the open-air display at Moscow-Kh odynk a airfield.

( Yefim Gordon )

Above and Below: 11-28 04 Red (em 5300577 1) is on d ispl ay at th e Russian A ir Fo ree Museum in M onino.

( Yet /III Gordon)

Ab ove: 11-28 0 I Red (CAl 36603807) is part of the o pen-air display at Moscow-Khodynk a air field. ( Yefi lll Gordon)

Above: T his Beagle, preserved at th e Civil Aviation Mu seum in Ulyanovs k (cAl 56605702), is supposedly an II-20. with a n appropriate (now faded ) Soviet flag and winged Aerotl ot logo. However, there a re reaso ns to believe that it was painted like th is after co ming to the mu seum and is really Soviet Air Force 38 Red! No te the 11-28 nose titles. ( Yefim Gordon)

Above: T his stripped-out hul k of a Beagle sat for many yea rs on the far side of the airfield at Kubinka AB. ( Yefim Cordon)

Left: The rear fuselage and tail unit of East German AF Il-28 208 Red , showing the tail turret; the cannon have been rem oved, prob ably to be displ ayed sepa rately. ( Yefim Cordon)

Abore and BeIOl I' : Former East Ge rma n A ir Forc e 11-28 208 Red (c/11 55006448) p reserved at Ba utzen Mu seum . This was the o nly EGAF Beagle to wea r a ca mo uflage finish . [ Yef in, Gordon }

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The Muz eum Lotnictwa i Astronautyki boas ts a n Il-28U serialled S3 Red

(CA l

692 16),

( Yefilll Gordon )

Above : Polish Air Fo rce 11-28 65 Red (c/ll 22 12) is preserved on the prem ises of the Officers' Higher F lying Schoo l in Debl in. ( Ye/ illl Gordon )

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Abore: 11-28R 72 Red (c /it 41909) resides at th e Mu zeum Lotnictwa i Astronautyki (Ae rospace M use um) in Krakow. ( Yefim Gordon }

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Above: Th e forward fuse lage of Il-28U S3 Red in Kra kow.

( Yei /III Gordon )

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Above: Alb an ian Air Forc e H-5 3608 at Rinas A B. T iran a. wit h Avia 14 31-6 1 in the backgrou nd.

( Key Publishing )

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Ab ove: Work underway o n B-5 308 Red, wit h a hardened aircraft she lter (HAS) - not meant for the bomber - behind it. Note the excellen t finish on thi s aircraft. ( RA RT)

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A bove: Romanian Air Force BT-5 407 Red is non-airworthy a nd sto red at Baca u A B.

( RA RT)

Above : Looking somewhat weather-beaten, B-5s 703 Red and 706 Red sit on the gras s at Bacau in non-fl ying co nd ition. ( R AR T)

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Ab ove: Romani an Air Force B-5s parked at Borcea- Fete sti AB.

( RA R T)

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A bove: The Plexiglass of th e ca nopy yellowed by age, Bulga rian 11-2843 Red sits at the Bulga rian Air Force Mu seum in Plovdiv. ( RA RT )

Above: N H-2 in full splendo ur at its home ba se, Utt i.

( RA RT)

Ab ove: Finnish Air Force 11-28 N l-l-l Ol in its origina l gui se with green-pa inted engine cowlings.

( R A R T)

Above: An impressive line-up of H-5s at a PLAA F airbase during a milita ry exercise: bo th flight and ground crews a re gathered ncar each aircraft. ( China 's AviationIndustrv)

Above: Thi s ano nymo us H-S is in the o pen-ai r di sp lay at the PLAAF Museum in Dat an gshan , keeping compa ny with a Na ncha ng CJ-S (licence-built Yak-I S Max) basic train er. ( F C. W Kiismann)

Above: Ha rb in H- S bo mbe rs in th e fina l assem bly shop. ( China' s Aviation Industry )

Above: H-5s cru ising over the Tien-Shan .

( China Aircraft)

Above: Thi s 11-28, which escaped to Taiwan on 11 November 1966, exemplifies the green camouflage worn by some PLA A F Beagles. It is now on display at the ROCAF museum at Taoyuan AB. ( RA R T)

:::-=

Above : PLAAF H-5s droppin g bomb s during an exercise.

( R A R T)

Abore: Thi s H-5 (44690 Red) preserved in the People's Liberation Arm y Air Force Mu seum at Datangshan AS has a non- stand ard nose glazing with a second optically flat pane l in front. ( Helmu t mil/her)

A bove: The FNAF Beagles wore cr ude ly applied green and blac k camoufl age.

( RA R T)

Ab ore: A Nigerian 11-28 sharing the ra mp at Enugu with Mi G -17F NAF-6 IS.

( RA R T)

Tnt IL-28 FAM ILY · 49

as ea rly as 1953 and tested on specially modified 11-28 a nd Tu-4 bombers. Design ed by a team under A. D. Nad iradze. the U B-2000 F bore a certain resemblance to the G erman Frit: X gliding bomb of World War II vintage. with a sq ua shed -X wing a rra ngemen t to provide adequate ground clearance. However. the wings were of delta planform with inset rudders. a nd the ca sing had a con stant diameter (in contra st. the German bomb had trapezoidal wings and a bul ged warhead) . Tests showed that two o r three sma rt bombs were enough to destroy a target measuring 30 x 70 m (98 x 229 ft) which would have required the expend iture of 168 FAB-1500 dumb bombs. Hence in 1955 the U B-2000 ente red production and was included in the VVS inventory as the U B-2F C haika (Seagull) or 4A -22 . A bo ut thirty 11-28s specia lly equipped to ca rry these PG Ms were built in 1956. This weapo n was carried externa lly under the fu selage. Outwa rdly the 11-28-131 could be identified by a sma ll a ngular fairing under the nose. p robably housing the guida nce an tenna for the bomb. The U B-2 F was a lso ca rried by specia lly modified Tu-1 6 Badger-A bombers which ca rried two such bombs on underwing pylons. ~

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I1-28PL anti-submarine warfare aircraft The late 1950s and early 1960s saw ano ther escalation o f the Co ld War which nearlv turned into a full -blown hot wa r during the C uban missile crisis. The deploym ent o f Soviet ballistic missiles to C uba wo rried the USA a nd its NAT O all ies immen sely. ca usi ng them to step up their submarine activities. Th is. in turn. led the Soviet Unio n to bolster its Navy. includ ing the Naval A ir A rm. Not having eno ugh ASW a ircraft to monit or the activities of Western navies a long the Soviet U nio n's marine bo rders and destroy. the AVMF decided to convert so me o f the bombers it had o n its strength. The aircraft converted for the ASW ro le were mostly Tu-1 6 Badgers and 11-28s. For instance. the Baltic Fleet's 759th OMTAP" totdel'nvy minno-torpcdnyy aviapolk - independent minel aying a nd torped o-bomber regimen t) converted ten 11-28 bombers and torpedo-bom bers (11-28T ). which were redesignated 11-28PL (protivolodochnyv - a nti-submarine ). These a irc ra ft were fitt ed with the SPA RU55 so nobuoy receiver (samol yotuoye preeyomnoye avtoniaticheskove rahdioustrovst vo - airborne aut o• matic radio receiver device. 1955 model) con stituting part o f the Baku so nar system recently adopted

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9 Some sources state the unit as the 769 th OMTA P.

by the AVM F (the same system was fitt ed to the Kamov Ka-25PL H orm one- A shipboard ASW helicopter). The bomb bay was big eno ugh to carry RG B-N so no buoys (ralulioghidroakoosticheskiv booyi and depth charges witho ut requiring modifications. The SPARU-55 was a superheterody ne receiver working in the 49.2 to 53.4 MH z waveba nd. This range was split into eigh teen preset frequencies through which the receiver cycled a utomatically. If a signa l from a sono buoy was detected on o ne of the frequencies. the receiver locked o nto it. enabli ng the o pera tor to determine if the sono buoy had rea lly detected a subma rine. If that was the case. he activated the SPARU-55"s direction- finder mode. and the aircraft homed in on the o perating bu oy to attack the su bma rine. A maj or drawback o f the SPARU-55 was its long cycling time (in automatic mode it needed 110 seco nds to switch from one bu oy to the nextl), An o utwa rd identi fication fea ture of the 11-28PL may have been several add itio na l blade aeria ls on the a ft fuselage underside: these were probably associated with the SPA RU-55 receiver. In 1962 the AT- I ASW torpedo was included in the AVM F inventory: it could also be carried internally by the 11-28PL. being 3.9 m (12 ft 9.54 in.) long and weighing 530 kg ( 1.1 68 lb ). Officially the reason for the 11-28PL's existence was the necessity to quickly receive ASW support once it had been requested by whoever spotted the unfriendly subma rine. since the 11-28 was more than twice as fa st as the obsolete piston-engined Beriyev Be-6 Madge fl ying boat o pera ted by the Soviet Navy at the time. Besides. the fl yin g boat s were diffi cult to operate in winter when their bases froze up. But perhaps the real reason was the naval comma nd's wish to sto p the Beagle kennels from being di sbanded. as they inevitably would be. and keep the pilots fl ying. In 1966 the HQ of the Baltic Fleet's air arm approached the Soviet Navy's G HQ. requesting the format ion of two regiments eq uip ped with the 11-28PL. but the request was turned down. ~

I1-28Sh attack aircraft In the late 1950s the Ilyushin O K B considered adap ting the Beagle for the strike role. This involved install ation of a battery o f twenty un guided rockets in the bomb bay. This wo uld give adequate fi repower witho ut spo iling the a ircra ft's aerodynamics with high-drag external stores. The launch tubes were to be mounted almost vertically. firing down a nd aft: a sa lvo o f rockets eq uipped with sha pedcha rge wa rheads was expected to be an effective way o f dest royin g armo ured vehicles. The crew was ~

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50 • ILYUSHIN I L-2 8 BEAGLE

reduced to two, the navigator/bo mb a imer being superfl uo us. But it was quickly established that the efflux of twenty rockets impinging on the a irframe would make the aircraft unco ntrollable a nd the idea was dropped . However, the limited wa rload of the fighterbombers of the period forced the mi litary a nd the engineers to dust off the idea of a n Il-28 attack a ircraft. The specifi cation for such an a ircraft was drawn up in the spring o f 1967 - before the fa mo us Six-Day War, in fact. The aircraft was to have a com bat radius identical to that of the Suk hoi Su-7BM Fitter-A fighter-bomber but an o rd nance load two o r three times greater. The res ult was the Il-28Sh (S!J fOO rJI IOl'i k - attack a ircra ft). It feat ured twel ve underwing pylons for ungu ided rocke ts - fi ve o utboa rd and o ne inboard of each engine. This was considered a more acceptable approach, even at the expense o f the extra drag created by the externa l sto res. Possible weapons configurations included twelve U B- 16-57 rocket pods with sixteen 57 m m (2.24 in .) S-5 folding-fin aircraft rocke ts (FFA Rs) each, I " or six 250 mm (9.84 in.). S-24 rockets, o r va rio us gun pods, subm un itions containers a nd free-fa ll bombs. Depending o n the mission, the pilot cou ld select a salvo launch o r just two pylons, fo ur pylo ns, etc . Flight tests which began in 1967 showed that even when all 192 S-5 rockets o r all six S-24 roc kets were tired at o nce, the engines showed no inclinat ion to surge o r flame o ut. The Il-28Sh commenced State accepta nce trial s in October 1967. The test pil ots repo rted t hat the aircraft was suitable for low-level a nd ultra-low-level strike missions. It was established that fl ying at and delivering accurate rocket/bom b strikes fro m altitudes right down to 60 rn (. 196. ft) could be mastered by service pilot s without any trouble; fl ying still lower, though,. demanded a lot of concentration and extra training . T he aircraft cou ld be prepared for a so rtie within four hours. Below 200 m (656 ft) the Il-28Sh had a speed lim it of 660 km/h (356 kt). Fuel consumption at low altitude increased by 30-50 per cent as compared to the basic bomber because o f the externa l stores a nd the aircraft's combat radius with a fu ll load of FFA R pod s was 295 km (1 83 miles). ~

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T his poor but interesting shot shows th e prototype Il-28Sh attack a ircraft during trials, The many underwing pylons are clea rly visible. ( l ,:lilll Gordon arch ire)

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Yet. despite a ll its merits as a strike aircraft, the Il-28Sh had inadequate a rmour protection and the ejection seats were no t yet of the zero-zero type, which meant the crew had no chances of survival if shot dow n at low a ltitude. Hence the Ilyushin OK B discontinued develo pment of the Il-28Sh , and tho ugh o rizinallv 300 Il-28 bombers were slated for conversion for the gro und-attack role, only a few were eventua lly conve rted at the Soviet Air Force's ai rcra ft overha ul p la nts a nd delivered to fi rst- line umt s. ~

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11-28ZA weather reconnaissance aircraft O n 23 Februa ry 1959 the State Committee on Aircraft (GKAT - Gosoodahrst vennvy kom itet po aviatseeonnoy tekhnikei issued an order concern ing the development of the Il-28ZA tzondirovsclichik atmosfery - lit. atmosphere sam pler ) weather reconnaissance aircraft for civil aviation needs. A few Beagles were converted to this configuration . Unfortunately almost nothing is known abo ut this version.

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Target-towing versions

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a) Soviet versions (Il-28BNI) Two versions (the basic bomber a nd the Il-28 R ) were widely used as target tugs - bo th for testing new AA guns and for training fighte r pilots. The specia l eq uipment fo r thi s missio n included a BLM-I OOO(B LM - IOOOM) o r BLT- 5 winch insta lled in the bomb bay a nd a 17BM-2 (17 BM-2M) or PM3Zh winged target towed o n a cable anywhere 11 ft) 10 n g. For be tween 5 a nd 2,500 m (16-8.202 . take-off a nd landing the ta rget was connected to the aircraft by a rigid link per mi tti ng operation from bo th paved a nd unpaved st rips. The bomber version used sho rt link age rod s, whereas the Il-28R was fitted with long o nes. The installatio n of target-towing equ ipment did not seriously affect t he a ircraft's CG position , which stayed well within the prescribed .

10 U B = oonititsecrovunnvy blok - sta nd a rdized [F FA R] pod: the UV-16-57 designa tion sometimes found in Western litera ture is incorrect. S = snarvad . >- in thi s case. un guided rocket. I I Bl\'1 = booksiroo vemaya mishen' - towed target: PM = plahner-niishen' - gliding target. Some so urces stated a towing cable length o f 20- ~ .5 00 m (65- 8,202 It), ~

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TH E IL-2S FA ~II LY • 51

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A n II-288M target tug based on a standard bomber with a gliding gunnery target in tow. t Ycfim Gordoll arch ire)

42Blue. an I1-2SR converted to II-288M co nfiguration (note tip tanks). takes off with a target connected by a rigid towba r. The aft position o f the tactical code is noteworthy. {Ycfim Gordon archivc)

52 • ILYUSHI N

I L-1 8 B EAGLE

Table 1·1. Comparison of performance cbaracteristics of 11-28 + 77Bl\I-2l\1 combination and 11-28R + Pl\I-3Zh combination

Climb time. min :

to 1.000 m (3.280 ft) to ·-LOOOm (13.1"3 ft) to 8.000 m (26.246 ft) to 10.100 m (33.136 ft) to 10.900 m (35.761 It) Range at 10.000 m (32.808 ft)/620 km/h (335 kt), km (miles) Range at 8.000 m/540 km/h (292 kt), km (miles) Ma ximum range. km (miles) Endurance at 8.000 m/540 km/h Ma ximum endurance Power loading at sea level. kg/kgp (lb/lb st)

limits. The target-towin g versions are sometimes referred to as I1-28BM ibooksirovsch chik misheney >target t ua). T he fie ld pe rfo rma nce of 11-28 bombers with a 20,1 00 kg (44.3 12 lb ) gro ss weight a nd I1-28Rs with a 19.822 kg.... (43.699 Ib) .....gross weight enabled them to .... operate wit h targets fro m conc rete a irstrips at lea st 1.800 m (5.905 ft) long. At a gross weight of 22.207 kg (48.957Ib). the 11-28R cou ld operate with target s from concrete airstrips at least 2.300 m (7.545 ft) long. End ura nce wit h a towed ta rget was 2.5 hours. Table 14 above gives some performance characteristics of an 11-28/7 7BM-2M com bination (TOW 20.050 kg/44.202 lb. fuel capaci ty 7.990 lit.l1.757.8 im p. ga l.) a nd an 11-28R/PM-3Zh combination (TOW 22.207 kg/48.957 lb. fuel capacity 9.550 lit.l2,10 1 im p. ga l.), When towed ta rgets were supplemented by rocketpowered target drones the 11-28 ta rget tugs were converted into co mbined tugs/d rone launchers. The drones were carried on underwing pylons between the nacelles a nd fuselage in much th e sa me way as the upgraded I1-28T ca rried torped oes. They were la unched a nd flew on towards the shootin g range when the ai rcra ft reached a n appropriate altitude. Apa rt from towed targets. the I1-28BM based on the standard bomber version co uld ca rry PM-6R and PM-6G target drones (PM = pikeeruvuschchaya ntishen ' - diving ta rget). These looked rather like bombs with overgrown fins a nd were eq uipped with smoke tracers and recovery parachutes. The 11-28R and I1-28T could not be mod ified to carrv.. these drones because of the reconnaissance and torpedo-bomber versions' increased T OW (which would be excessive if the drones were carried) and some struct ural details which rendered the conversion impossible. The PM-6 drones were carried on special underwing pylons attached on two pairs of swept V-st ru ts. ~

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11-28 + 77Bi\I-2l\1

11-28R + Pl\I-3Zh

3.5-4.0 9.75- 10.25 23.75-24.0 n.a. 57.0 845(524) n.a. 1.475 (9 16) n. a. 2 hr44 min 3.3

4.0 10.75 -"7 . -.,-) 55.0 n.a. n.a. 1.140 (708) 1.555(965) 2h r 07 min 3 hr II min 3.56

The delivery system sp un up the d rones' stabi lizing gy ro s. using power from the ca rrier a ircra ft. a nd dropped th e drones singly or simulta neo us ly a t a preset a ltitude bet ween 2.300 a nd 8.000 m (7. 545- 26.246 It), The d rones were a imed using the optica l sight or radar: in a n emerge ncy they co uld be d ropped by eithe r the pilot or the navigator. With two d rones th e aircra ft's service cei ling was limited to 9.600 m (3 1.496 ft ), a nd the take-off run increa sed by 300 m (984 ft).

b) East German version T he East Germa n 11-28s converted into target tuzs d itTered slightly from their Soviet counterparts. as no rigid target s were used . A drum with a 2.000 m (6.560 ft ) steel cable was ca rried in the bom b bay on the sta nda rd bom b crad les. To t his a fabric 'sock' 8 m (26 fn long a nd I m (3 ft). in dia meter was a ttached: it was neatly rolled up a nd suspended from the bomb crad les before ni ght. A sma ll roller was att ached to the lower fu selage to stop the cable from sc uffi ng the fuselage skin as it paid o ut. Some types o f anti-aircraft guns (i ncl ud ing the S-60) were radar-directed . so aluminium co nes had to be inserted int o the sock to provide a radar signature. Pri or to entering the shoot ing range the p il ot lowered the !laps 20° and slowed the aircraft to 280 km/h (1 55.5 kt) to prevent the target from being ripped a pa rt o r torn off by th e slipstream as it unfolded . The navigat or then dropped the target. which unwound the cable as it deployed: the drum was fitted with a centrifugal brake to make sure the cable un wound smoothly, .. Two or three m inutes later the ta rget was fu lly depl oyed . the observer in the gunner's cabin monitoring it. (A ll armament wa s usually removed.) When the sortie was completed the cable and target were jettisoned . us ua lly by means o f a pneu~

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Til E IL-2 S FA ~ II LY • 53

matic release mechanism. but the cable could also be cut by a pyrotechnical guillotine in case of malfuncti on. After landing the cable was rewound and ready for ano the r mission; the target could also be reused. unless it had been shot to shreds.

c) Romanian version At least one Romanian Air Force Harbin H-5 (Chinese-built I1 -28. see below). serialled 307 Red was converted for target-towing duties. using equ ipment developed by the Air Target Sweden A B company. An MBV7S Mk 3 target-towing winch was installed in the bomb bay. with a faired cable outlet amidships; the cable was 4.500 m (14.765 ft) long. The winch worked with a KR-45-430 sleeve-type target eq uipped with an AS-13 1SC acoustic miss di stance sensor; the target was hooked up under the fuse lage before night.

II-28M target drone

and designed to destroy aircraft with a radar crosssection (RCS) similar to that of the 11-28. The radio control system enabled the II-28M to take off , climb to cruise altitude. make manoeuvres and land if the drone wa s lucky eno ugh to stay in one piece. At first this was oft en the case - the first prototypes of the Model 400 SAM did not score a single hit on the drones! Another anti-aircraft missile developed by the Lavochkin OKB. the 207A. was tested between June 1953 and November 1954; for instance. three test launches against I1-28Ms were made in October 1953 . two of the missiles having shaped-charge warheads and the third a directional fragme ntation warhead. State acceptance tria ls of the 207A began in September 1953. using 11-28Ms and Tu-4s as targe ts. The target drones Ilew at 9.500-20.000 m (31.168-65.6 16 It) and up to 35 km (2 1.7 miles) from the launch site. All the targets were ei ther destroyed or substantially damaged. the missi les' accuracy . being within 7- 58 m (23- 190 ru Not all I1-28Ms were radio-controlled. however. Some Beagles phased out by the VVS were given a brush-up by the manufacturer to make sure mechanical failure wo uld not prevent the aircraft from fulfilling its final mission. Then a pilot would take the doomed bomber into the air. climb to a predetermined altitude. engage the auto pilot and eject when told to do so by ground cont rol. Test pilot Fyodor D. Bogdanov made 31 such Ilights in 1952-7. ejecting at 12.500 m (41.01 0 ft ). ~

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Besides towing ta rgets. ma ny Beagles ended up as targets themselves! In the late 1950s many obsolete I1- 1 8 bombers were converted into remote-controlled high-speed target drones designated II-28M (lor mishen' (taruet l) and used for testing- new antiaircra ft missile systems. To be precise. development of this version was brought about by Semyon A. Lavochkin's OKB-301. which sta rted design work on the Model 400 surface-to-air mi ssile in 1955. This missile was intended for point defence of important targets. such as major industrial cities. ~

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11-"SBM s were a lso supplied to foreign customers: this is Finnish Air Force ( )(:11111 Gordon archive:

H-3. a no the r converted I1-2SR.

Sot • ILYUSHI NIL-28 B EAGLE

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An II-28M target d rone seen thro ugh the gunsight o f an attacking fighter. ( Ycfim

Test and development aircraft I. Avionics testbeds a) 11-28LL radar testbed One 11-28 (identity unknown) was converted in 1952 fo r testing the RP-6 Sokol (Falcon) radar" a nd desII-28LL iletavuschchava laboratoriya - lit. iznated eo flying labo rat ory )." Th is rada r with a 30 km (1 6.2 nm) detection range had been devel oped by O K B-339 under G. M. Koonyavskiy for two interceptors - the Ya kovlev Yak-120, which entered prod uction and service as the Ya k-25 Flashlight- A , and the Lavochkin La-200B. Initial tests were perfo rmed on a converted Boeing B- 17G Flying Fo rtress. (While this type was not o lTicially supplied under ~

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12 RP = ralulioprectsei : radio sight: thi s was the Soviet term IO J[ lire con tro l radars at the tim e. 13 Thi s Russian term is used ind iscri minately a nd ca n denote a ny kind or testbed (avio nics. engine. equipment. wea pons. etc.). a n aerodynamics research aircra ft o r co ntro l co nfigured vehicle ICCV): a weather resea rch aircra ft . a geophysica l survev aircraft . etc. ~

Gordon urchivc)

the Lend-Lea se programme, a number of B-1 7s which had crash-landed o n Soviet-held bases a fte r raid s on G ermany were repaired a nd used by the Soviet A ir Force. ) When it transpired that developme nt o f the Yakovlev fight er was taking longer tha n predicted a nd that the La-200 would be the .first to receive the new radar, Semyon A . Lavochk in suggested that a heavy a ircraft but a faster o ne than the 13-17 be used to bring the radar up to scratch. The 11-28 was the o bvious choice. To accommodate the radar the bomber's no se glazing was cut away at fuselage frame 2 .and replaced by a cylindrical metal structu re (pa rt o t the Ya k- I20's nose incorporating the avionics bay ). The huge di sh o f the RP-6 was enclosed by a la rge glassfib;e radome which had an a lmost hemispherical fro nt end instead of the usu al pointed o r ogiva l shape. The conversion work was d one by Lavoch kin O K B specia lists under the supervisio n o f the Ilyushin OKB (which wa s not directly interested in the project but held responsibility for the 11-28 anyway). The fam ous test pilot M ark L. Gallai flew the 11-28LL. with R. A . Razum ov as test enginee r: the latt er was the wo rse 011 sitt ing in a dark a nd

THE IL-28 FAM ILY ' 55

extreme ly cramped bay aft of the rad ar set - all th at remain ed of th e navigat or 's sta tion. A tot al of 33 !ligh ts was ma de wit ho ut a ny pro blems: th e test program me, whic h ended in Decem ber 1952. includ ed simulated interception of rea l a ircraft. Later, tests of th e Sokol rad ar co ntinued o n the La-200B intercepto r pro to type which, afte r being rejected by the VVS, found use as a testb ed . By th e end of 1953 the rad ar had been perfected and was fitte d to the lateprod uction Yak-25M fro m 1954 onwa rds, repla cing the RP-I D Izum rood (Em erald ) rad ar fitted to early Yak -25s as a sto pga p measure.

h) missile targeting systems research aircraft In 1960 the Ministry of Defence's Centra l Research Institu te No . 30 (TsNII -30 - Tsentrahl 'nyv tiaoochnoissledovatel 'skiy inst itoot i joined forces with N II-2 an d the Research In stitute of the State Co mmittee for Electro nics (N Il G K RE - naoochno-issledovatel'skiy inst itoot Gosoodahrstvennovo koiuit eta po rahdioelek troni ke t to develop active rad ar homin g systems lor an ti-shippi ng missiles. To th is end it was necessary to ana lyse the character istics of the rada r pulse re!lected from surface ships. Thus a n 11-28 and a Lisun ov Li-2 Cab transport (a licence-bu ilt Dou glas DC-3 derivative) were co nverted into avionics testbed s eq uipped with two experimen ta l rad ars and special recording equipment. T he meas uremen t an d recording system (MRS)

develop ed by N II-2 was hou sed in the Beagle's bomb bay. It includ ed a high-speed cine-camera ca ptur ing th e rad ar pulses re!lected from the ship and appearing as lines on the radar display. The two testbeds mad e mo re tha n fifty !lights from Kirovskoye ai rbase on the Cri mea n Peninsula, using Black Sea F leet cr uisers. des tro yers and minesweepers as targets. The ships were either anchored on the roa ds tead at Feodosiya or mo ved on prede termined headings. Measur ement s were mad e in 38 !light s at 2,000- 5,000 m (6.651- 16.404 ft) and 110-1 67 m/sec (360- 547 ft/sec) at 10-50 km (5.4-27 nm) ra nge. Forty-three measuremen ts were ma de with the cruisers, 64 with des troyers and 40 with minesweepers at var io us sighting a ngles in var ious sea sta te co nditions. T he resul ts were analysed by a co mp uter. which ma de it poss ible to develop algorithms lor determining th e class of a ship in a group: thi s helped to develop guidance systems lo r standoff anti-shipping missiles. c)

An 11-28U coded 18 Blue was apparent ly con verted into an avionics test bed of some sort. sporting several non -stan da rd aerials under the forward and rea r fuselage. Unfort unately no de tai ls are know n of thi s ai rcra ft: it may have been a navaids ca libration (!light checker) aircraft.

This Il-28 u' coded 18 Blue. a p pea rs to have been co nverted to a n avio nics testbed o f some kind : not e th e man y non -stan dard ae ria ls un de r the fuse lage. ( Se/"!!' ~I ' and D m i t /"(I ' Ktnn issa ro v archi vc)

56'

I LY USHIN I L-2 8 B E. /CLE

II. I1-28LL ejection seat testbed The 11-28 was extensivelv• used for research and develo pment work. In the early 1960s severa l aircraft were converted into testbeds for va rio us systems of the , ostok (East) manned spacecraft under development by Sergey P. Ko rolyovs team. One of these was 10

Blue (c/n 53005 710), a n ejection seat testbed used to test. among other things, the ejection seat o f the Vostok's re-entry vehicle. Interestingly, thi s aircraft has likewise been referred to as Il-28L L. T he bulky Vost ok ejection sea t wa s installed in

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10 Blue. the I1-28LL ejectio n seat testbed. firing the seat for th e Vosto k spacecra ft 's re-entry vehicle. ote th e photo calibration markings on th e fuselage a nd tail a nd th e dual cine-camera fairin gs on each wingtip. r Ycf im co,.do" archivcl

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Close-up o f the Vostok ejection seat as it clears the superstructure above th e modified bomb bay. ( },:/ im

Gordon archive]

THE IL-28

FAM ILY '

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A no ther view o f the Vosto k ejec tio n sea t as it sepa ra tes fro m the 11-28. spo uting terrific n am es. Note th e SM -50 chase pla ne in th e background . I Sag, -r and Dtnit ri v Komissan»: archivc)

The sa me aircraft as it fires a no the r ejectio n seat from th e heavily m odifi ed gunn er' s sta tio n. ( l i:/illl Gordon archive}

58 ·

I LYUSHI N I L-2 8 B EAGLE

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An ex pe r i me n t,~ 1 sea t is ejected fro m ~h e r~ar s t ,~ t i o n o r 10 Blue. It appears that the seat fires through a simulated cockpit ca no py. shattering the glazing w ~ l c,h IS painted 111 stripes for better vis ua lization. ote the stabilizing booms tipped with drogue pa rachutes extending aft from the headrest: this may be an early version o f the fam ous Z vezda K-36 seat. ( Ycfin: Gore/oil archivv)

the faired-over bomb bay immediately ahead of the wing torsion box and pro truded above the upper fu selage: hence a large tea rdrop fairing wit h Ilattened sides had to be insta lled aft of the pi lot's cockpit to protect the test pi lot sitting in the seat fro m the slipstream. Additiona lly, the tai l gunner's compartment wa s replaced by a large slab-sided fairing extending much further aft, from which another ejection seat could be fired both upward s and downwa rds. Cine-cameras were mounted in teardrop fairil~gs .above and below the wingtips to capture the ejection sequence. The Vostok ejection seat was tested successfu llv by future cosmona ut Gherman Titov, The Mikova~ SM -50 fight er (aka MiG-1 9S U. an experimental version of the MiG-1 9SF Farmer-C with a ventral U-19 liquid-propellant rocket booster) acted as chase plane and camera ship.

III. In-flight refuelling system testbeds a) fighter IFR system integration A Voro nezh-built 11-28 (0 I Red. c/n 2402 10 1) was converted into a makeshift ta nker train er used for testi ng the hose-and-drogue Ilight refuelli ng system developed by O K8 -91 8 led by G uy lIyich Severin. " The aircraft worked wit h the the ten th prod uction G orkiy-built MiG-19 Farmer-A coded 10 Red (c/n 592 10 110). converted at LII in late 1957. This fighter had no fewer than four dummy refuelling probes (one ahead of the winds hield and three on 14 Now th e Z vezd a (Star) Joint-St ock Co m pa ny. T he com pa ny lat e r d evelo ped the U PA Z - t A Sak ha lin podded HD U (U PAZ = oonifitsc..ro l't Il/IIYY podvcsnoy ogreg ,," r zuprahvki -: sta nda rd ized sus pend ed. i.e. externa l refuellinu unit) used o n the I1 -781I1-78M ;\/idos tanker. bu t is best known for its 1'.-36 ejec tion scat.

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T HE I L-2 8 FAMI LY ·

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T ho ug h of poor qual ity. these shots are extre me ly interes ting. showing an 11-28 refuelling tanker trailin g a hose from the bomb ba y. a nd a not he r Beagle eq uipped with a nose-moun ted refuelling probe taking o n fuel from thi s air craft. ( ! ,:/illl Gordon urchivc)

the po rt wing) becau se the best locatio n had to be determ ined experime nta lly. An experimenta l winch em ulating a hose d rum unit (H OU) was insta lled in the I1-28's bo mb bay. paying o ut a 5 m m (0.19 in.) steel cab le with a drogue of 640 mm (2 ft 1.19 in.) dia meter to a point 42 m (137 ft) beyond the bomber's tail. Initia lly a 36 kg (79 Ib) unstabi lized drogue was used . After the first four nights. howe ver. it was rep laced with a drogue incorporating a stabi lizing device 100 mm (3.93 in .) wide mounted 60 mm (2.36 in.) from the ba se. Both models had a lock for engaging the probe. The MiG-19 would make contact with the tanker at 7.000 m (22.965 It) and 450-470 km/h (250-261 kt) lAS. approaching from a sta nd-by position 10- 20 m (32-65 It) behind the d rogue. Contact was usua lly mad e in a climb. with or wit hout side slip. Ap proach speed varied fro m 0.3 to 12 m/sec (1-39 ft/sec) or 1- 30 km /h (0.54- 16.2 kt) lAS. After making co n tact the M iG -19 stayed locked into th e d rogu e for 3-5 seco nds. then slowed down and broke away. For safety's sake the d rogu e

lock was set at an unlocking force of 60-80 kg ( 132- 176 lb ). Us ua lly the lighter carried drop tanks to incr ea se mission time. Test pilot Nikolai O. Goryayn ov (who has the distinction of being the first Soviet pilot to successfully ref uel a heavy bomber in night) was ass igned proje ct test pilot for the tanker tr ain er. On 28 August 1957 he made a night to check the opera tion of the winch . Th e drogue was depl oyed at 7.000 m (22.965 ft) and 400. 450. 500 and 550 km/h (2 16. 243. 270 a nd 297 kt) lAS. After that. test pilots S. F. M ashk ovski y, Pyotr I. Kazmin a nd Sergey N. Anokhin mad e ten refu elling !lights. as det ailed in the table below. T he ten th !light had to be cut sho rt when the d rogue entered the fighter 's air int ake and collap sed . the debris damaging on e o f the eng ines. Th e trials showed that the chances of making contact with the ta nker depended mainly on the d rogue 's stability. which left m uch to be desired. as the drog ue twisted vio lently in the slipst rea m.

Tabl e 15. In-fli ght refuelling test result s Flight

Date

M iG- 19 pilot

S uccess ful a tte mpts

o. I 0. 2 No.3 No. 4 No.5 No.6 No.7 No. 8 No.9 No . 10

18 September 20 September 24 September 27 September 3 Oct ober 16 October 30 O ctober I Novem ber 7 December 27 D ecember

Ma shkovskiy Mashk ovskiy Mashkovskiy Mashkovskiy

2 of 4 (n ose pr ob e ) 2 of 7 (n ose probe ) 2 of 5 (n ose probe ) No co ntac t 1 0 1'33 2 o f 41 1 01' 12 2 of 34 9 of 30 o cont act

Ma shkovski y An okhin Ma shkovski y Ma shkovski y Ka zmin K azmin

60 • I LY USHI N

I L-~ 8 B EAGLE

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The II-'S LS h testbed was d eveloped to investigate th e po ssibilit y o f using skis o n tactical aircraft. This view shows the ex perimen ta l skid . a nd th e ball a st con ta ine r to which it is attached, in the full y rai sed positi on. ( J,:/illl G",..!"" archive]

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The 11-' SLS h ( I' Red. c/n 53005 1 1 ~ ) with the skid fully lowered. No te the non-retractable tWlI1 mainwheel s, ( ),:/im Gordon archive )

T il E IL-2 8 FAMILY ' 61

b ) bomber IFR system tests •

In due course the Soviet military put forward more stringen t requirements, which the 11-28 could no longer meet. One o f the greatest deficiencies was the Beagle's inadeq uate ra nge. However, at that stage it wa s deemed inadvisable to reti re the many 11-28s in VVS service, so someone suggested retrofitting the bombers with the probe-and -drogue refuelling system. To this end two m ore 11-28s were conve rted for real-life I FR system tests. One o f them was a tanker with a real HD U in the bomb bay, while the other Beagle featured a fi xed refuelling probe o lTset to port above the navigator's sta tio n. The two aircraft made successful contacts but the system was not fitted to Soviet Air Force 11-28s because A leksa nd r S. Yakovlevs OKB- 115 brought o ut the m ore promising Yak - 129 superso nic tactica l bomber which eventua lly entered product ion and service as t he Yak-28 Brewer.

with ballast to test it for va rio us loads: the whole assembly co uld be raised a nd lowered by hydraulic rams. The nose gea r unit was fi tted with larger wheels and th e the main units had widely spaced twin wheels rather than th e usual single ones. Thi s modified undercarriage co uld not be retracted, so the main wheel well d oors were deleted to avo id making cont act with the wheels. The skid was tested o n a irst rips with va rio us soil densities: th e aircra ft made high-speed run s but did not become a irbo rne. ~

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b) tracked landing gear testbed To enhance the Beagle's ability to o pera te fro m tactical airfields a special tracked landing gea r was designed, built a nd tested o n an 11-28 pursuant to a Co uncil of Mini sters directive o f II January 1951. It all owed the bomber to o pe ra te from so ft , wet, soggy o r snow-covered airfields which rendered take-off with a conventio na l wheeled landin g gear very difficult or utterly im possible. The tests were considered successful, but owi ng to th e extra weight a nd comp lexity of the experimenta l landing gear. it was not retrofitted to p roduct ion aircraft. ~

IV. Landing gea r testbeds

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a ) 11-28LSIt

In 1958 a M oscow-built 11-28 coded 12 Red (c/n 53005112) was conver ted into the 11-28LSh testbed (LSh = Ir . :llIlo-re shassee - ski landing..........gear) for testing the efficiency and durability o f aircraft skis designed for dirt strips. The aircraft wa s fitted with a semi-retractable sprung skid under the centre fuselage. The skid wa s equipped with pressure senso rs and m ounted on a hollow box which co uld be tilled

The Il-28LSh runs a long a dirt strip. ( Yctin: Gordon archivc)

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V. Engine testbeds a) Soviet testbed One 11-28R (identit y unknown ) was modified to test a liquid -propell ant rocket mot or developed by L. S. D ooshkin . The experimental powerpla nt was

62 • ILYUSHIN IL-28 S E.IGLE

This Il-28R served as a testbed for a liquid-propellant rocket molar developed by L. S. Doosh kin. ( )