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K TT UIL-D I NG, D A'Y T 0 N, 2, OHIO

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f El B I., )

r RE~1~~1EO - 10th Part of' AAE/868. 1

4:r MINISTRY Of _ SUPPLY

AEROPLANE AND ARMAMENT

EXPERIMENTAL ESTABLISHMENTBOSCOMBLE DOWN

VW\OMFB.1.WB7.258

li. X 20 W~l. MK. 5'* HISPANO GUNSGUNNERY ACCEPTANCE TIALS

5- Hti RztC1'*!NT (OVENNUENT. DC tI0i.'hi TO P4Y

F-LF'S -inS Wmi PRS W

-- 2. TH4E INfOitA,:O~it iOULOBE, LAFEGUANDINIDRUs..:S l)'$GNtD 10 G;VE iTHE MAME S IANDAilO oFSleCutsI'; AS THAT I~i:AIoAlrED BY HER MAJESIV1'SGOVtR;.MEt4 I N THE UtWI ICINGOOM.

3.' THE WhFRMAil0k CONIAME Nf t THIS -RE~PORlTSK'ULVO MMt 8t tAWC4J.A'ED Li4SIDE f0.,;kftiKT

DEPARTMI:-.dS Wfl HOUTlE FRI" RIW8 # OF I HtMNTRY OF. SUPPLY.

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TO-ANY_ INFRINGEMENT OF THE OFFICIAL SECRETS ACT.

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Any person other than the authorised holder, upon obtaining possession of this document, by finding or otherwise,

should forward It, together with his name and address, In a closed envelope to :

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Letter postage need not be prepaid : other postage will be refunded.

All persons are hereby warned that the unauthorised retention or destruction of this document is an offence against

the Official Secrets Acts, 1911-1939.

AAEE FORM 1. 10151 (A1068) Wt.8856j1527. 32M. 2. 5152-. . & S. Gp.S48

10th Part of Report No. AAEE/868

AEROPtLANE MD AETdERM-1 fPNAL SAB S rNT 30N1353BOSCUME DOWN

Venom FB. 1. VE. 258

4.x 20 mm. .. Mc 5K Hispano GunsGunnery Acceptance Trials

A. a A.EE. Ref.: AAKE/5903/42.M.0.S. Ref.: 7/Armts/2027/0.683.Period of Trial : 7th March, 1952 to 12th August, 1952.

Propess c£ issue of Report

Re-ort No. Title

5th Part of AAm/868 VV.613 Flight at high Mach numbers without wing tiptanks.

6th - do - VV.613 Cockpit Appraisal.7th - do - VV.613 Qualitative harilling trials, including flight

at high mach numbers, without tip tanks.8th - do - VV. 613 Qualitative hardling trials with 2 x 80 gallon

wing tip tanks.9th - do - T.255 Brief check handling tests after incorporating

minor modifications.

Gunnery Acceptance trials have been completed on the Venom Fighter BomberNk.1 Aircraft (D.H.112) in accordance with .O.S. letter and trials pro-forma7/Armt/2027/0.683 dated 31st May, 1951.

A total of 117 sorties were flown with three aircraft during which 55,899rounds were fired. The guns were fired at speeds up to the limiting speed ofthe aircraft, under 'g' conditions and in full coambat maneeuvres, and at highaltitude.

During the trial a considerable number of sorties were flown to determinethe best configuration of link deflector having regard to the necessity forkeeping the links clear of the fuselage with the minimum effect on the perfor-mance of the aircraft.

Concurrent]y with the rest of the trial the causes of damage to blasttubes on other Vampire/Venom aircraft were investigated ard a satisfactoryblast tube evolved.

It is the opinion of this stablishment that the gunnery installation ofthe Venom F.B.I. aircraft (D.H.12) is acceptable for Service use provided thatthe modifications reommerxed are incorporated.

This report is issued with the authority of .... .

• /" - Camnodcre,Comanding, A. & A.E.E.

Iist of......

-2-

List of Contents

1, Introduction 32. Description of Installation 33. Method of Trial 34. Results of Trial 35. Conclusions6. Recommendations 7

List of Ai Resicc

Air Firing Records - WE.258 IAir Firing Records - WE.258 2Intensive firing Records - WE. 259 3Flight at High Mach No. - WE.258 4Harmonisation diagra 5Gun rates of fire 6Link deflectors 7

List of IllustrationsFigule

General view of aircraftExternal crack on fairing panel - forward arerture for

nose-vheel door hinge 2Internal crack as at Figure 2. 3Crack on fairing panel at aperture for rear hingeCannon spout - cracked lip 5Damage to packing strip of cannon spout fairing 6Standard and modified blast tubes 7Suggested type of modified blast tube securing clip 8Fractured quick release assembly at rear mounting 9Failure of return spring guide and roe, S. I. gun 10Failure of return spring guide and-rod - S.O. gun. 11Original D.H. deflector 12Locally designed deflector 13Modified D.H. deflector 14Redesigned D.H. deflector - external view 15Redesigned D.H. deflector - internal view 162?' fairing for link deflector 17Final internal form of deflector fitted with 2" fairing 18Link flow - 4.5" deflectors 19Link flow - 3.5" deflectors 20Link flow - 2.5" deflectors 21Link flow - 2" deflectors 22Link flow - No deflectors. 23

/Introduct ion....

n "RESTRICTED

-3-

I. Introduction

Gunnery acceptance trials have been completed on Venom Fighter BomberMc. 1 aircraft WB. 255, IFF.258 and VC.259 in accordance with M.0. S. letter and

trials pro-forma 7/Armt/2027/o.683 dated 31st 1o1Y, 1951.

The trial was carried out on E. 255 from 16th July 1951 to 29th August

1951 and on WE.258 and E.259, from 7th March 1952 to 12th August, 1952.

2. Des ipt ion of Installation

The installation is similar to that of the'Vampire I aircraft, which isdescribed in the 6th part of Report No. AALB/819,a.

3. Method of Trial

3.1. Initial Examination

3.1.1. The installation was checked and the guns removed and replsoedby a proven set of guns.

3.2. Ground Functioning

3.2.1. Approximately 1950 rounds were fired during ground function-ing trials on WE. 255 and 475 rounds on WE. 258.

3.3. Air Fntionin

3.3.1. Twenty threc air firing sorties were flown on YM. 255 during

which the guns were fired at speeds up to the limiting speed of the aircraftunder 'g' conditions and in full combat manoeuvres, ant at high altitude.

3.3.2. Sixty-two air firing sorties were flown on VE. 258 undersimilar conditions to those stated in para. 3.3.1. above.

3.3.3. A total of 11,114 rds. was fired in the air with WE. 255 and28,019 rds. with WE. 258.

3.3.. During Intensive Flying Trials on Y'E.259 thirty-two airfiring sorties were flown, the majority being at high speed at low level duringwhich 16,766 rds. were fired.

3.3.5. The total number of air firing sorties flown during the

trial was 117, during which 55,899 rds were fired.

4. Results of Trial

4.1. Initial Examination

4.11. No difficulty was found in removing and installing the guns,although the position of the gun heater pipes makes it advisable to adjust theinboard magazine carrier tie-rods before installing the outboard guns.

4.2. Gr'ound Functioninjg

4.2.1. Approximately 1950 rds. were fired during ground function-ing trials with 1E. 255 and 475 rds. with 1%. 258. No signs of blast damage wererevealed.

4.2.2. The range of gun adjustment was checked and found to beapproximately 00 32' in all directions from the centre line of the gun mounting.

.2.3. 4hen the guns are adjusted to maximum combination of eleva-tion and 'too-in' all four cannon spouts are liable to be hit if the guns arefired.

ISTRICTED

4.2.4, The guns and sight were harmonised without difficulty andthe view over the nose was measured. With the head in the normal sightingposition the downward view through the sight is 40 42', and alongside the sight100 25'.

4.3. Air Functioning WE. 255

4.3.1. Twenty-three air firing sorties were carried out with WE.255during which 11 ,1 14 rds. were fired. Details of sorties and rounds fired areat Appendix 1.

4.3.2. Air firing was carried out during these sorties at speedsranging from 250 knots to 535 knots, the limiting speed of the aircraft, under'g' conditions and in full combat manoeuvres. At 45,000 ft. the guns were firedat speeds up to I.M.N. 0.855 (limit 0.86).

4.3.3. As a result of the high stoppage rate, especially oases ofthe cartridge cap being lightly struck, the guns were removed for testing.Similar stoppages were experienced during butt tests.

4.3.4. The aizraft was returned to the makers for investigationof handling characteristics.

4.4, Air Functioning 'TRE.,258

4.4.1. Sixty-two air firing sorties were carried out with WE. 258,during which 28,019 rds. were fired. Details of sorties, rounds fired andstoppages are at appendix 2.

4.4.2. N'o stoppages occurred which wero attributable to theinstallation with the exception of those during the first air firing sortie.These four stoppages were caused by the riginal link deflectors which havebeen rejected.

4. 4 3. Air firing was carried out at speeds ranging from 450 knotsto 535 knots,under 'g' corlitions ard in full combat manoeuvres and at 40,000ft. at speeds up to I.M.W, 0.835 wnich was the maximum at which this aircraftwas a stable gun platform.

4.L4. At speeds of 450 knots and over there ,nre a considerablenumber of link strikes under the fuselago. Trials were carried out with anumber of different deflectrs to elininate these strikes without affectingthe performance of the aircraft. This part of the trial is dealt with fully inpara. 4.7.

4.4.5. Ifter the 36th sortie (rounds fired 16,383) the port cannonspout fairing was found to be cracked ut the cut-away portions giving clearancefor the rear noso-wheel doc- hinges. All four cannon spouts were crakemd at thefairing (se e 2, 3., 2% and 5,). The panels were repaired and refitted. There

was no recurrence -f this failure.

4.4.6. Orne sortie was flown at 40,000 ft. during which the gunswere fired at I.M.N. 0.82, 0.83 and 0.835. Firing had no effe o e handlingof the aircraft at these speeds (See Appendix 4).

4. 4 7. Four sorties were flown at 40,000 ft. during which the gunswere fired after 45 'o 50 mins. at that height. The ambient temperatures werein the region of -56'C at height during these sorties.

4.4.8. ALter the 34th sortie it was found that the quick releaseassembly at the rear mounting (Stores Ref: 26FC/4028) was fractured

(Fig. 9). Two other quick release assemblics wore changed du to the slidetubes becoming slick in the brackets.

/4.4.9...

4.4.9. During the 62nd sortie the return srng ide and ro of

the starboard outer gun failed and were partially ejected through the backblock of the gun. They cam to rest alongside the starboard accumulator bear-ing on a nut on the accumulator tray about 2y" from the rear bulkhead of thegun bay (see fig. 11). This failure should be compared with that mentionedin para. 4. 5. 8. and fig. 10.

4.410. Five casas occurred on WE.258 and four on WE. 259 offailure of maxiflux leads causing stoppages. In two cases the ledd short-circuited in the plug causing a fuse and stopping two guns. In the remainingcases a failure, usually in the plug stopped a single gun. The fault appearsto be in the rather flimsy nature of the contacts in the plug and in the factthat the plug is very difficult to grip and withdraw especially with oilyfingers. The result of this is that there is a tendency for the cable to beaccidently pulled when the hand slips. A plug having stronger contacts and apartial flange at the rear to form a grip is considered desireable.

4.4.11. Rate of fire tests were carried out during low and highlevel sorties, and detailed results, together with a brief history of the gunsemployed, are given at Appendix 6.

It should be noted that, at this Establishment, all 20 m.m guns mustpass an acceptance test on a ground mounting, using both Nk.5 and M.7 B.F.H. Isbefore they are classified as suitable for installation in an aircraft.

4.5. Intensive Gunnery Trials - WE. 259.

4.5.1. As part of the intensive flying trials (which will becovered by a separate part of this report, in preparation) 32 air firing sor-ties were carried out with 1E.259 (See appendix 3 for details of sorties).A total of 16,766 rounds was fired during these sorties.

4.5.2. Twenty five sorties were flown at 2,000 ft. I.A.S. 480 kts.to 510 knots, with the exception of sortie No. 4 when the guns were fired at450 knots I.A.S.

4.5.3. Five sorties were mpale against ,,round targets when firingnormally took place at 400 knots although three attacks vore made at 450 and500 knots.

4.5.4. Two sorties were flown at 40,000 ft. when the guns werefired at I.M.N. 0.81 to 0.84.

14.5.5. It was necessary to change the port and starboard cannon

spout fairings after the 18th and 27th sorties respectively owing to cracks inthe f airings.

4.5.6. On five occasions cannon spouts cracked at the fairing inthe manner shown in Fig. 5. These were repaired by vwlding and there were nocases of the cracks re-appearing. It should be noted in this connection thatit was necessary to change the fairing after a maximum of a further elevensorties after welding for other reasons, see also para. 4.4.5.

4.5.7. After the 5th sortie it was found that the packing stripalong the upper edge of the cannon spout fairing on each side of the aircrafthad been forced out as shown in Fig. 6. This is thought to be caused by gasescaping during longitudinal movement of the blast tubes, forcing its way outof the forward gun bays. The packing strip was repaired and no further troublewas experienced. However it should be noted that modified blast tubes werefitted on the part side after the 7th sortie and on the starboard side afterthe 12th sortie. A similar failure occurred on E. 258 when using standardblast tubes.

/4.5.8....

U6

4.5.8. After the 7th w 12th sorties it was found that the frontcone of a blast tube (standard pattern) was damaged clue to hammering againstthe cannon spout.

4.5.9. After the 12th sortie it was found that the pin retaining

the return spring guide and the head of the return spring guide rod hadfractured on the starboard inner gun allowing both these parts to move backand protrude through the back block of the gun. Due to burrs they stopped5/16" short of a main fuel pipe at the base of the fuselage tank (see Fig. 10)While the incidence of this failure is very low it constitutes . serious hazardto the aircraft especially as the guide and rod can be ejected considerablyfurther than in this instance and so fracture the fuel pipe. The position ofthe port inner gun to fuel pipesis similar to that of the starboard inner gun.

4.6. Blast tubes

4. 6.1. Owing to damage which occurred on other aircraft of theVampire/Venom type, trials were carried out on blast tubes concurrently withthe gunnery trials.

4. 6. 2. A modified blast tube was evolved by the Martin BakerAircraft Co. which was found to-be satisfactory. Approximately 50 firingsorties were carried out with this type mostly at speeds of 500 knots and over.Fig. 7 shows the original and modified types. The maker's drawing No. of themodified type is MBT60/5350.

4. 6, 3. A detailed report on this trial is made in mE/ReportNo. Arm, 115.

4.6.4. The present nethod of securing the blast tubes to thefront mountings of the guns is not considered strong enouEh.

In two cases the jubilee clips fractured across the cut-awey portion givingclearance for the outer eccentric lock. It is considered that a clip similarto that shown in fig. 8 should be introduced. This clip is re-inforced atits narrowest part and is secured by a nut and bolt.

4.7. Link Deflectors

4.7.1. As a result of numerous link strikes on the underside ofthe fuselage and of strikes on the booms nd tanilplane of other Vampire andVenom aircraft at speeds of 450 knots I.A.S. and over, link deflectors werefitted to WE. 258 by the makers. (See fig. 12). On WE. 255 links had enteredthe air scoops under the fuselage at speeds as low as 350 knots (See appendixI Sorties 1 - 3).

4. 7.2. These deflectors proved unsatisfactory as the links piledup in the deflectors and link chutes and stopped the guns. (See appendix 2,Sortie I).

4. 7.3. Extensive trials were then carried out to determine thebest configuration of link deflector having regard to the need for keeping thelinks clear of the fuselage with the minimum effect on the performance of theaircraft. Forty air firing sorties were flown during these trials.

4.7.4. A link deflector consisting of an extension link chutefitted to the gun access door and an external leflector was found to be satis-factory. The extension chute fits over the end of the linc chute from theB.F.M. and is belled out at the inner end to allow for movermnt of the linkchute during harmonisation and gun changes. The deflector is of approximatelystreamlined section and has a maximum depth of 2-". Fig. 17 shows the deflec-tor and fig6 18, the extension link chute. The aircraft's performance athigh mach number is not affected by tbese deflectors. (See appendix 4).

4.7.5. AlthouFh the link deflector in its final form eliminatespractically all link strikes, the urrlerside of the fuselage, the booms and thetailplane must be checked for damage ofter each air firing sortie.

/A.M....

-7-4,7.6 Details of the various deflectrs tested are given in

appendix 7 and figs. 13 to 18 inclusive, Films of the link flow at 500 kts. LASwere taken with a aine camera mounted on the port pylon. Specimen prints fromthese are shown in figs. 19 to 23.

4.8. Re-arming..

4.8.1. A crew of four men re-armed the aircraft in 12 mins fromthe time the aircraft stopped in the dispersal. Ammunition and loaded B.F.M. Iswore ready at the dispersal.

4. 82. A more experienced crew of four men re-armed the aircraftin 15 rins. In this case the ammunition was teady at the dispersal but theB.F.M. Is off the aircraft were re-loaded in a workshop 75 yds. away -Td re-fitted on the aircraft.

4.8.3. The magazines of the G.45 camera and the G.G. S. recorder

were changed in these times.

4. 9. Harmonisation

4.9.3. A harmonisation diagram has been produced for the conditionslaid down by Air Iinistry (appendix 5. ) Accuracj trials were carried out withthe guns and sights harraonised to this diagram at P.E.E. Pbrdine and it wasfound to be satisfactory.

4,10. Gun and Ammunition Bay TEAperature Trials

h 10.1i These are fully reported in the 12th Part of this Report,which is suwmarised as follows:-

".10.2. "The temperatures of the Lun bodies and amunition tanksin Venom FB. Mk. 1. VIE.255, were measured in flight under the most severeprobable conditions. The results showed that the gun body and ammunitiontanks temperatues would be too low under the coldest and too high under thehottest conditions required by AP.970. Covering and uncovering the gunmuzzles had a negligible effect on the terperatures.

5. Conclusions

5.1. The gunnery installation of the Venom FB.1 tircraft (DH. 112) isacceptable for Service use irovided that the molification detailed in paras6.1. below is incorporated retrospectively, and that consideration be givento the remaining modifications listed in para. 6.

6. Recommendations

6. 1. Link deflectors of the type shown in the De Havilland drcraftComparq's drawing "D.H.112 Link Chute Extensions "drawing No. 12Z.2345 butwith the 2J' fairings produced by that firm, must be fitted as starard. Theunderside of the fuselage, the booms and tailplane must be checked for damgeafter each air firing sortie.

6.2. Blast tubes of the modified MT/60 pattern with the Edge Type Rimto the Martin Baker Aircraft Compaxyts drawing No. lBT/60/5350 should befitted as standard. Until this is done blast tubes should be checked fordamage after each air firing sortie.

6,3a A stronger method of scouring the rear end of the blast tube tothe front mounting eccentric should be introduced. A reinforced clip similarto that shown in fig. 8 is considered suitable.

6*4, Owing to the possibility of hitting the cannon spouts, firingihould not take place until the guns mnd sights have been harmonised to anapproved diatam. This is considered to be an undesir ,;e feature and a modi-fioation is roonnmnded to clear the guns through the 7 range of adjustment.

/6.5 .....

4 -8-

6.5. The possibility of moving the fuel pipes from behind the axes ofthe inner guns or of irotecting the pipes from the results of a further failureof the type mentioned in paras. 4.4.7. and 4,5.8. should be considered.

6.6. A re-dcsigned plug for the M(axiflux unit, see para. 4.4.10, isconsidered desireable.

6. 7. To avoid the danger of the guns freezing at high altitude and ofthe ammuntion deteriorating at low altitude, the heat supply to the gunsshould be increased and some form of automatic control should be introducedinto the system to shut off the beat vthen not required.

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Appen4l

Venom W.F. 258.

Flight at High Mach No,

10 Introduction

This report covers three flights on Venom W.F. 258 carried out on July 22rdand 23rd. The second and third flights were as a result of certain Mach No.characteristics exhibited by the aircraft during the first sortie which involvedfiring the guns at high Mach No. high altitude.

2. Conditions of Aircraft

1st Flight Load Clea Zance No. 5.Aircraft clean, 600 rounds of ammunition.

2nd Flight Load Clearance No.5.Minus link ejector chutes.

3rd Flight Load Clearance No. 5.Minus link ejector chutes: aircraft fitted with newelevator spring tab.

3. Results of Test.

Ist Flight: (High Mach. No. high altitude firing)

At 42,000 feet the aircraft was put into a shallow dive at a power settingof 10,100 revs. The aircraft was trimmed at Mach. No. 0.80.

At Mach. No. 0.82 there was a slight nose down change of trim. At thislach No. the pilot fired a short 2 second burst without arn noticeable effectupon the handling of the aircraft. At Mach. No. 0. 83 there was a slight lateralrocking due to alternate wing heaviness. Imother short burst was fired withoutany particular effect. At Mach. No. 0.835 the aircraft began a fairly strongnose up change in trim requiring almost full forward movement of the stick tohold. Two more bursts were fired in this condition without arq noticeable effectsupon the aircraft. On this run a peak Moaoh. No. of 0. 84 was achieved when theaircraft nosed up so strongly that the pilot was unable to hold the dive withthe stick fully forwardi.

There was no evidence that the firing of the guns caused any change inthe Mach No. characteristics but the pilot did several runs at high Mach No.between 42,000 - 38,000 feet to verify the constant behaviour of the aircraft.In each case the aircraft behaved in the same way.

Mach No. 0.80 - Aircraft in trim0.82 - Slight nose down0.83 - Lateral rocking0.835 - Moderately strong nose up with the onset of elevator

buffeting and elevator ineffectiveness.0.84 - Strong nose up, elevator only partly effective.

Stick fully forward and the nose still rising.Pronounced elevator buffeting.

The strong nose up at Mach No. 0.84 depended upon how quickly the Mach.No. was increased. Thus in the steeper dive the nose up with the stick fullyforward induced an accelerometer reading in the region of 1- - 2 g indicated.

Two runs were maie at approximately 33,000 feet. The aircraft reacted inmuch the same way except that the nose up was not so pronounced. There wasless buffeting of the elevator which was more effective.

2nd Plight, (Link ejector chutes removed).

The link chutes were removed in order to check whether they were thecause of the characteristics exhibited on the previous test.

/The tests.*.

-2-

The tests were repeated but there was no change in the Mach. No.charactristi esd

3rd Fligh t (New elevator spring tab).

After the previous flight it was noticed that there was a small amountof play in the elevator spring tab arm. The tab was removed and a new onefittede

In this condition the previous tests were repeated.

There was no change in the strong nose up at Mach No. 0.84, but thiswas now ocmbined with a strong right wing down which the pilot was unable t ohold due to the aileronsbeboming insufficiently effectiveb

The pilot considered that although the elevator lost effectiveness tothe same extent as on the previous flight there was now less elevator buffeting.

Four runs were made between 42,000 - 38,000 feet withconsistent results.The recovery of the aircraft from the right wing down position was autauticas the tendency disappeared as soon as the nose had risen sufficiently for theMach, Not to reduce.

Two runs were made at 33,000 feet and although the nose up was as beforethis was now accompanied by a right wing drop.

4. Conclusions

Neither the gun firing or the link chutes affect the Mach No. characteris-tics of the aircraft.

The change in characteristics at high Mach No. appear to be caused by ageneral deterioration in finish.

/Appeidix 5..

)i APPENDIX 5.

is VENOM FB.

01 50 YARD DIAG-RAM FOR

~SPREAD HARMONISATION AT 500 YARDS.

OPERATIONAL USE

HARMONISATION CONDITIONS.

1. GUNNERY.

A. AIRSPEED: 250 KTS. I.A.S.

oB. TRUE ALTITUDE: 25,000 FT.

tu C. AMMUNITION: H.i. MK.I.

D. GRAVITY DROP, 4-8 FT.

2. ROCKETRY.

L

f4c

B. DIVE A PE NDX0.

SP CREAE ARMONGE STNAT0 YARDS

OPERTIONL US

VENOM F.B.I.50 YARD DIAGRAM FOR

SPREAD HARMON ISATION AT-500 YARDS(PERATIONAL USE

HARMONISE FIXED &MOVING GRATICULESWITH RANGE DRUMSET AT 500 YARDS.40

-SET AT GUNS. .

U) u

R J. SAI

udl

4 .30,00

Os0 4-,o

SE ARCAF DTM TAL OW FR8 .OZONTL

SET PIRRT DATR UM 00 TALPOW FRO~ HORIZONTAL.

SETOTINRoN030 PFO OIOTL

o R.P. SIGHT SETTINGS.

0.G.G.S. MK. 4E. CLASS 2.

60 LB. &25 LB. HEADS SET RtA4GIE DRUM M'TO 2-4.0 YARDS.

32pendix 6

Gun Rates of Fire and Brief Hiistory

Date:- 3.4.52.

Flight Data:- Height 1,000 ft. I.I,.S. 535 -515 kniots. Level flight.

Gun Position:- P.O0. P. I. S.I. SIO.

Gun Number:- Hl1657 J4506 1111786 L3363

Burst:- 1 507 492 455 5272 512 495 458 5313 537 533 (Stoppage) 5574 470 470 4605 507 507 5066 537 507 5.7 495 468 503

534 520 5289 503 493 524

10 503 500 "516

Date:- 10.9.52

Flight Datau- Hei[ght 40,000 ft. 1. 1. N. 0. 76 Level fligrht. Fired after45 minutes at Height. Ambient tenperature - 5100.

Gun Position:- POP. SI. S.0.

Gun Numb er: 1110673 1110710 H110505 L7220

Burst:- 1 760 658 718 6822 785 687 753 6883 798 684 725 6954 805 682 745 694

1111657 - Brief History -(Aircraf t VN. 258)

Total ids.__________________Date Fired R. 0. F, Remarks

eceived at A. & A.E.E. 23. 1.51 124 - Prior to accep-irst tested at A. &' A.E.E. - - -tance test.assed acceptance test - - --nstalled in subject aircraft. 3." 52 1616 -

ir Firing R.0.F. tests. 3.4.52 1766 5103emoved from subject aircraft. 131.7.52 3710 -

Stoppages:B. F. It. -I Electrical -I Total 2Rounds fired J0

J,4506 -Brief History -(Aircraft WVE. 258)

Total Eds._____ _________Date Fired R.0.F. Remarks

Received at A. & L.E.E. 22.1.52 368 -

First tested at A. & A.E.E. 28.1,52 468 --

Passed 1,cceptance test* 31.3.52 1268 675, Mk 7* B. F. ILInstalled in subject aircraft. 3.4.52 1368 --

Air firing R.O.F. test* 3.1452 1468 498-Removed frca subject aircraft. 31.7*52 3570 --

Stoppages.:B.F.M. -2 Total 2Rounds fired. 1 902

-2

H.11786 - Brief History - (Aircraft WE.258)

Total Rds.Date fired R. O.F. Remarks

Received at A. & A.E.E. 1.7.49 - - evious history

first tested at A. & A.E.E. 24.1.50 100 - unknown.Passed acceptance test. - - -Installed in subject aircraft. 3. " 52 3487 -Air firing R.0.F. test. 3.4.52 3497 457 StoppageRemoved,from subject aircraft. 3.4.52 4732 -

Stoppages:Gun - 3 B.F.M. - 1 Electrical - 2 Total 6Rounds fired, 1033

L3363 - Brief history - (Aircraft WE. 258)

.Total Rds.Date fired R.-O.F. Remarks

Received at A, & A.E.E. 6.11.50 15 - -

First tested at A. & A.E.E. 17.9.50 115 -Passed acceptance test. 20.9.50 565 670 Inc 7 B.F.M.Installed in subject aircraft 3.".52 1315 -Air firing R. 0.F. tests. 3,4.52 1465 519 -

Removed from subject aircraft. 17.6.52 j3281 - -

Stoppages:Misfired - I Total IRoundu fired. 1666

H.10673 - Brief History - (Aircraft YfE.258)

Total Rds.Date fired R. 0. F. Remarks

Received at A. & A.E.E. 3.2.51 83 - -

First tested at A. & A.E.E. 23.2.51 123 - ricr to accep-Passed acceptance test. - - - tance test.Installed in subject aircraft 27.3.52. 1899 - -

Air firing R. 0.F. test 10.9.52 6068 787. -

Removed from subject aircraft. 11.9. 52 6206 - -

Note: The very high rate of fire of this gun was subsequently reduced to 735 bythe fitting of a strong F.M.U. slring, and further reduced to 690 by using aNo.53 hole in gas plug.

Stoppages:Installation - 1 Electrical - 3 B.F.M. - 4 Maintenance - ILmmunition - I Gun 1meakage - I Total 11Rounds fired. 4007

H10710 - Brief history - (Aircraft WE. 258)

Total Rds.Date fired. R,0.F Remarks

Received at A. & A.E.E, 3.2.51 91 -

First tested at A. & I.E.E. 23.2.51 191 - Prict to aocep4.Passed acceptance test. - - -: tane test.Installed in subject aircraft. 27.3.52 2142 -

Air firing R.OF. test, 10,9,52 7115 677Removed fra subJect aircraft. - 7237 - Still n Mf-

Stoppages: Installation - I Electrical - I Gun functioning - 2Broken belt -I Total 5Roumds fired.

-3-

H.10505 - Brief histry - (Aircaft WE.258).

Total Rds.Date fired. - R.0.F. Remarks

Received at A. & A.E.E. 3.2.51 82 - -

First tested at A. & A.E.E. 23.2.51 102 - Prior to acoep-:Passed acceptance test. - - - tance test.Installed in subject aircraft. 27.3.52. 3457 - "Air firing R.0.F. test. 10.9.51 8220 721 -

Removed from subject aircraft. - 8346 - Still in A!c.

Stoppages:Installation - 1 B.F.M. - 3 Maintenance - IElectricaal - I Gun breakage - 1 Total 7Rourls fired. 4889

L7220 - Brief histary - (Aircraft WE. 258)

Total Rds.Date fired R.O.F Remarks

Received at A. & A.E.E. 3.2.51. 87 - -

First tested at A. & A.E.E. 23.2.51., 187 - Prior to accep-Passed acceptance test. - - - tance test.Installed in subject aircraft. 27.3. 52. 3361 -

Air firing R.0.F. test. 10.9.52 7265 690 -

Removed from subject aircraft. - 7398 - Still in L/C.

Stoppages:Installation - I Electrical- I Gun breakage - IAmmunition - I Maintenance - I Total 5Rounds fired. 4037

/Appendix 7.. .•

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FIG 2 EXERAL RAKSON

[r2.XENLFAIRING PANEL AT FORWARDAPERTRE FOR NOSE WHDOOR HINGE.

FIG 3 INTERNAL CRACKI

ASAT Fir.

A.&AE. NEG.W 1588.1

Fir. 5. CAN'JON SPOUT - CRACKED LP

FIG 6. IDWAGE To PACKING -STRPOF CANNON SPOUT FARING.:

A.&E.E NG. 15868.

A.- -E N

PIG7 SANDRD AND MODIFIEDBATTUBE

FIG. 8 SUGGESTED TYPE OF MODIFIED BLAST

L TUBE SECURING CLIP

F&AENEG. N9 15868,

FG.QFRACRE QUI ELEASE -ASSEMBLY'ATREAR MOUN"TING.

AFG. 10. FAILURE OF RETURN SPRING GUIDEAND ROD, SI. GUN. SHOWING POSITIONRELATIVE TO MAIN FUEL PIPE.

RIG II. FILURE O(F-RETURN -SPRING GUIDE-AND ROD, S.O. GUN, SHOWING POSITIONIRELATIVE TO ACCUMULATOR

FnG12. OAUIHT

N13 L CALLY E IGN 0EFLECTMR.

FIG.4 MODIFIED O H DEFLECTO

f&AEECT(OR

I F16 15 REDESIGJED D.H DEFLECTOR.EXTERNAL VIEW.

41P

GU#X CoeK~4

INTERNAL VIEW.

FI.17.22 FAIRING- FOR LINK DEFLECTORNOTE: INTERNAL SURFACES PAiNTEDWHITE FOR ILLUSTRATION ON LY

FIC I. FNL INTERNAL FORM ODEFLECTOR FITTED WTHAIRI

A.&XE E 1568.1

LINK FLOW

IFG 19 -- FIG.20. 35"DEFLECTORS

AS &0 A TNCN.1

,FG2 "ELCOS' I.3 ODFE7

LINKS 5LO T

Edsttl

Defense Technical Information Center (DTIC)8725 John J. Kingman Road, Suit 0944Fort Belvoir, VA 22060-6218U.S.A.

AD#: AD005795

Date of Search: 3 March 2009

Record Summary: AVIA 18/4004Title: Venom FB 1 WE.258 (Ghost 3): 4 x 20 mm Mk 5* Hispano Guns; GunneryAcceptance TrialsAvailability Open Document, Open Description, Normal Closure before FOI Act: 30 yearsFormer reference (Department) 868 Pt 10Held by: The National Archives, Kew

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Access to UK public records is governed by statute, namely the PublicRecords Act, 1958, and the Public Records Act, 1967.The document has been released under the 30 year rule.(The vast majority of records selected for permanent preservation are madeavailable to the public when they are 30 years old. This is commonly referredto as the 30 year rule and was established by the Public Records Act of1967).

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