Gaining An R.A.F Pilots Brevet In WW II
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Pom Pax (#12020),
This is pure gold ! I want to know: is there a note of the Mark, or (better yet) an Airframe No? I have a DVD of "100 years of the RAF", and remember a flash of a logbook page. I think it came from an old BBC Documentary "The Spitfire Girls" of years ago. But it was too short for my old eyes to take in detail. If you still have the recording (or the DVD), could you give me the min & sec into the showing, please, so's I can (hopefully) find it again.
This may solve an old puzzle. Capt. "Winkle" Brown records that he tested a VV (Mk. unstated) and found it useless as an aircraft (which it was). But also said that it was inferior as a dive bomber to the Stuka, in that the VV could not dive vertically (unlike the Stuka), but only at 60-70 degrees. Now we know the reverse is true (for the Mks I and II - US A-31, anyway). Don't know about the Mk.III (also a US A-31), which only came in with the war over. But who is going to gainsay the (late) Eric Brown, the most famous test pilot of all time ? Our esteemed friend "Chugalug" will remember all this .
But if Brown had been given a Mk.IV (US A-35) to test? Many were supplied to us, the RAAF and just about anyone on earth who would take them off Vultee's hands. They had been modified from the Mks. I-III by setting the wings from zero to a +4 degree Angle of Incidence (at the request of the USAAC, which then wanted no part of any of them, A-31s or A-35s).
Far as I know, the only real use anybody found for the IV was as a target tug. Never flew one, never even seen one, but reckon that with an AoI you could not dive vertically, as even with full nose-down trim, at 300 mph the thing would push up hard off target in spite of all you could do.
RIP Mary Ellis ! All respect to a grand old dame (and all the other girls - and men - of the ATA). Only ever saw one in my time (full story at the end of my Post Page 123 #2455 of "Pilot's Brevet").
You will know that the only VV left on earth is in the (temp closed) Camden Museum. Narellan, Sydney. We have established that it is really a Mk. I, but for some reason, the Museum has re-fitted a 0.50 Browning in the back to replace the twin 0.303s it should have. This is the hall mark of a Mk.IV, which has caused much controversy on these pages.
Cheers, Danny.
This is pure gold ! I want to know: is there a note of the Mark, or (better yet) an Airframe No? I have a DVD of "100 years of the RAF", and remember a flash of a logbook page. I think it came from an old BBC Documentary "The Spitfire Girls" of years ago. But it was too short for my old eyes to take in detail. If you still have the recording (or the DVD), could you give me the min & sec into the showing, please, so's I can (hopefully) find it again.
This may solve an old puzzle. Capt. "Winkle" Brown records that he tested a VV (Mk. unstated) and found it useless as an aircraft (which it was). But also said that it was inferior as a dive bomber to the Stuka, in that the VV could not dive vertically (unlike the Stuka), but only at 60-70 degrees. Now we know the reverse is true (for the Mks I and II - US A-31, anyway). Don't know about the Mk.III (also a US A-31), which only came in with the war over. But who is going to gainsay the (late) Eric Brown, the most famous test pilot of all time ? Our esteemed friend "Chugalug" will remember all this .
But if Brown had been given a Mk.IV (US A-35) to test? Many were supplied to us, the RAAF and just about anyone on earth who would take them off Vultee's hands. They had been modified from the Mks. I-III by setting the wings from zero to a +4 degree Angle of Incidence (at the request of the USAAC, which then wanted no part of any of them, A-31s or A-35s).
Far as I know, the only real use anybody found for the IV was as a target tug. Never flew one, never even seen one, but reckon that with an AoI you could not dive vertically, as even with full nose-down trim, at 300 mph the thing would push up hard off target in spite of all you could do.
RIP Mary Ellis ! All respect to a grand old dame (and all the other girls - and men - of the ATA). Only ever saw one in my time (full story at the end of my Post Page 123 #2455 of "Pilot's Brevet").
You will know that the only VV left on earth is in the (temp closed) Camden Museum. Narellan, Sydney. We have established that it is really a Mk. I, but for some reason, the Museum has re-fitted a 0.50 Browning in the back to replace the twin 0.303s it should have. This is the hall mark of a Mk.IV, which has caused much controversy on these pages.
Cheers, Danny.
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Danny,
I am afraid not pure gold just a very small nugget. The best guess where to find on the program is at or before 41 minutes. As it was recorded off a not advertisement free channel there may be 6 or more minutes of junk on my record.
I posted all the information there was. The clip starts with a view of left hand page of log book with summary for July '45 showing types flown, then McGregor reading them followed by a longer shot of log book showing full summary including hours for type.
If some U.K. based Ppruner could locate and get sight of the relevant log book this should show relevant information of this flight. Given being July '45 a Mk.IV (US A-35) seems likely.
July '45 summary shows:-
Argus ……. 3-50
Spitfire ….. 3-20
Corsair ….. 1-20
Barracuda . 1-55
Sea Otter .. 1-40
Vengeance 1-30
Tempest …. -55
Firefly...…. 1-00
Wildcat...…. -50
Anson
Wellington
Ventura
Mitchell
No explanation given for lack of information on last four types.
I am afraid not pure gold just a very small nugget. The best guess where to find on the program is at or before 41 minutes. As it was recorded off a not advertisement free channel there may be 6 or more minutes of junk on my record.
I posted all the information there was. The clip starts with a view of left hand page of log book with summary for July '45 showing types flown, then McGregor reading them followed by a longer shot of log book showing full summary including hours for type.
If some U.K. based Ppruner could locate and get sight of the relevant log book this should show relevant information of this flight. Given being July '45 a Mk.IV (US A-35) seems likely.
July '45 summary shows:-
Argus ……. 3-50
Spitfire ….. 3-20
Corsair ….. 1-20
Barracuda . 1-55
Sea Otter .. 1-40
Vengeance 1-30
Tempest …. -55
Firefly...…. 1-00
Wildcat...…. -50
Anson
Wellington
Ventura
Mitchell
No explanation given for lack of information on last four types.
Last edited by Pom Pax; 31st Jul 2018 at 08:24. Reason: Trying to straigten table.....with limited success
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I would like to express my appreciation of the stalwarts (ca 500 daily) who still hit on: "Gaining an R.A.F. Pilot's Brevet in WWII" Thread (although it is currently languishing on Page 4 of "Military Aviation" Forum).
For many years it was the star of "Military Aviation" and the preceding "Military Aircrew" Forums, and even now has chalked up the greatest number of Posts (12,000 +) and "Hits" (3,000,000 +) of any other Thread on the Forum (if you exclude "CapCom", clearly a special case as by its very nature it will attract an enormous number of Posts and Hits).
I know that all that lives must die; but you must admit that it has been "an unconciable time a-dying" ! And it would be churlish not to acknowledge the latitude always shown to it by our Moderators, which has so contributed to its success over the years. Let's raise a valedictory glass to it, and also to Clifford Leach [RIP] - ("cliffnemo") who started it just over ten years ago.
Danny.
For many years it was the star of "Military Aviation" and the preceding "Military Aircrew" Forums, and even now has chalked up the greatest number of Posts (12,000 +) and "Hits" (3,000,000 +) of any other Thread on the Forum (if you exclude "CapCom", clearly a special case as by its very nature it will attract an enormous number of Posts and Hits).
I know that all that lives must die; but you must admit that it has been "an unconciable time a-dying" ! And it would be churlish not to acknowledge the latitude always shown to it by our Moderators, which has so contributed to its success over the years. Let's raise a valedictory glass to it, and also to Clifford Leach [RIP] - ("cliffnemo") who started it just over ten years ago.
Danny.
And it would be churlish not to acknowledge the latitude always shown to it by our Moderators, which has so contributed to its success over the years. Let's raise a valedictory glass to it, and also to Clifford Leach [RIP] - ("cliffnemo") who started it just over ten years ago.
Danny.
Danny.
Jack
I have at last reached the end of this great thread. It has taken over a year and I love it. One little problem today when I logged on I found that I have advanced 2000 posts,, last night I was happily following the adventures and noting the arrival of post 10,000 with the careful arrangements to allow Lord Danny to have that post,,, where pray tell have the 2000 posts gone. Page number is now given at 304,, but that was also page number at around the 10,000 mark
Danny:-
Indeed I do Danny, as I do your revelation of the incidence of the MkIV being some 4 degrees whereas its predecessors were set at zero. Thus the MkIV was not capable of an accurate 90 degree dive for bombing purposes, adding dive bomber to all the other uses it was useless at! I'm sure that must be what Winkle Brown condemned, just as you have done ofttimes.
All of which rather begs the question of the Stuka's angle of incidence. Was that also zero? It didn't seem to adopt the typical nose high attitude in Straight and Level as the Vengeance did in contemporary pics. I suspect that it was also a compromise like the MkIV, but perhaps somewhat less so. Certainly Luftwaffe tactics were to use a steep dive rather than a vertical one. That seemed to work well enough for their purposes, given a benign state of air superiority of course.
But who is going to gainsay the (late) Eric Brown, the most famous test pilot of all time ? Our esteemed friend "Chugalug" will remember all this .
All of which rather begs the question of the Stuka's angle of incidence. Was that also zero? It didn't seem to adopt the typical nose high attitude in Straight and Level as the Vengeance did in contemporary pics. I suspect that it was also a compromise like the MkIV, but perhaps somewhat less so. Certainly Luftwaffe tactics were to use a steep dive rather than a vertical one. That seemed to work well enough for their purposes, given a benign state of air superiority of course.
The old Ju87 had gull wings and a heavily spatted undercarriage. This would have brought the centre of drag to about the wing roots so it would have been quite happy pointing in any direction. In the Russian campaign when used in the anti-tank roles with underwing cannon the spats could, and in some cases were, removed.
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The old Ju87 had gull wings and a heavily spatted undercarriage. This would have brought the centre of drag to about the wing roots so it would have been quite happy pointing in any direction. In the Russian campaign when used in the anti-tank roles with underwing cannon the spats could, and in some cases were, removed.
https://en.wikipedia.org/wiki/Junker..._87_edit_1.jpg
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Chugalug, FED and MPN11,
All water under the bridge now. Would've liked to have tried a Ju-87 in or shortly after WWII, to see how it compared. I never even saw a VV Mk.IV (except one TT in the air postwar), so my opinion of it can be no more than that.
The Wehrmacht did well enough with the "Stuka" in Europe and Russia, but the USAAC turned its back on both its A-31 (VV I-III) and A-35 (VV IV). If the VV did any good at all, I reckon it was in Burma in 1943-44 when the Jap tactic of bunker-digging to drag-out retreat presented it with targets for which it might have been designed.
Fortunes of War !
All water under the bridge now. Would've liked to have tried a Ju-87 in or shortly after WWII, to see how it compared. I never even saw a VV Mk.IV (except one TT in the air postwar), so my opinion of it can be no more than that.
The Wehrmacht did well enough with the "Stuka" in Europe and Russia, but the USAAC turned its back on both its A-31 (VV I-III) and A-35 (VV IV). If the VV did any good at all, I reckon it was in Burma in 1943-44 when the Jap tactic of bunker-digging to drag-out retreat presented it with targets for which it might have been designed.
Fortunes of War !
Last edited by Danny42C; 17th Aug 2018 at 12:09. Reason: Erase !
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A long time reader of this thread, and board.
Yet with never contributing anything, as of yet.
Hopefully this video, is new to some folk.
Spitfire 944
www youtube com/watch?v=ie3SrjLlcUY
Not allowed to post URL's until after 10 post's.
Feel free , to re-post a clickable link.
Yet with never contributing anything, as of yet.
Hopefully this video, is new to some folk.
Spitfire 944
www youtube com/watch?v=ie3SrjLlcUY
Not allowed to post URL's until after 10 post's.
Feel free , to re-post a clickable link.
Last edited by T28B; 17th Aug 2018 at 15:27. Reason: plugged in link
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The Wiki on the Ju87 is incredibly long and detailed. Made for an interesting read, especially the attrition they caused in the early Eastern Front campaigns. But, as we all know, they needed air superiority ... which we denied them over UK. Huzzah!
FED:-
It seems that Captain Brown RN is in full agreement with you, given his quote in Wikki:-
Could you explain what you mean by the Centre of Drag? Given a symmetrical airframe wouldn't that act through the centre line of the aircraft, along with the thrust and lift vectors? I know that drag is a many splendored thing, what with profile, form, induced, skin friction, etc etc, but uncertain what if any of these components would be at or near the wing roots, given the inverted gull wings and u/c spats. Incidentally, wasn't the purpose of the wing shape to give adequate ground clearance for the quite large centre line bomb (unlike the Corsair where the prop diameter was the problem)?
The old Ju87 had gull wings and a heavily spatted undercarriage. This would have brought the centre of drag to about the wing roots so it would have been quite happy pointing in any direction.
It seems that Captain Brown RN is in full agreement with you, given his quote in Wikki:-
Eric "Winkle" Brown RN, a British test pilot and Commanding Officer of No. 1426 Flight RAF (the captured enemy aircraft Flight), tested the Ju 87 at RAE Farnborough. He said of the Stuka, "I had flown a lot of dive-bombers and it’s the only one that you can dive truly vertically. Sometimes with the dive-bombers...maximum dive is usually in the order of 60 degrees.. When flying the Stuka, because it’s all automatic, you are really flying vertically... The Stuka was in a class of its own
Could you explain what you mean by the Centre of Drag? Given a symmetrical airframe wouldn't that act through the centre line of the aircraft, along with the thrust and lift vectors? I know that drag is a many splendored thing, what with profile, form, induced, skin friction, etc etc, but uncertain what if any of these components would be at or near the wing roots, given the inverted gull wings and u/c spats. Incidentally, wasn't the purpose of the wing shape to give adequate ground clearance for the quite large centre line bomb (unlike the Corsair where the prop diameter was the problem)?
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jjayjackson (#12134),
In the tradition of this noble company, and in my (dishonorary) capacity as Grand (?) Old Man of this, the finest Thread on the Forum, let me welcome you aboard. Draw up a pew (if you can find one) in our cybercrewroom - and give the virtual stove a poke !
Matters arising:
1: I never knew the USAAC had Sergeant-Pilots in WWII (but obviously they did), presumably recruited from the hoi-polloi without the magic two years "College" - "University" to us. Never met one, but as an old Sgt-Pilot myself, would like a natter with one. Anyone know when this started and stopped and why ?
2: Col. Blyth Posted here about it on this Thread donkey's years ago, but "Search this Thread" (predictably) drew a blank ("chocolate teapots" come to mind).
3: Col. Blyth earned his DFC ! It was not healthy to fly over Berlin for half an hour in 1943 in broad daylight. Couldn't a FW190 or an AA shell get up to a Mk.XI PR, then ?
4: "Every pilot should have a chance to fly a Spitfire", the man said. Amen to that, say I.
5: The M.O. (Doc Savage) was able to take home movie film - and the censors let him send it back home to the US, in the middle of a war ? Didn't their "Security" utter a cheep ? In Burma we were not officially allowed to have still cameras (still less film) in case we were captured, and Jap Intelligence could make use of the material. Perhaps they reckoned that, by 1943, the war was over, and Britain was at peace ?
You see, when you throw a stone into a pond ............
In the tradition of this noble company, and in my (dishonorary) capacity as Grand (?) Old Man of this, the finest Thread on the Forum, let me welcome you aboard. Draw up a pew (if you can find one) in our cybercrewroom - and give the virtual stove a poke !
Matters arising:
1: I never knew the USAAC had Sergeant-Pilots in WWII (but obviously they did), presumably recruited from the hoi-polloi without the magic two years "College" - "University" to us. Never met one, but as an old Sgt-Pilot myself, would like a natter with one. Anyone know when this started and stopped and why ?
2: Col. Blyth Posted here about it on this Thread donkey's years ago, but "Search this Thread" (predictably) drew a blank ("chocolate teapots" come to mind).
3: Col. Blyth earned his DFC ! It was not healthy to fly over Berlin for half an hour in 1943 in broad daylight. Couldn't a FW190 or an AA shell get up to a Mk.XI PR, then ?
4: "Every pilot should have a chance to fly a Spitfire", the man said. Amen to that, say I.
5: The M.O. (Doc Savage) was able to take home movie film - and the censors let him send it back home to the US, in the middle of a war ? Didn't their "Security" utter a cheep ? In Burma we were not officially allowed to have still cameras (still less film) in case we were captured, and Jap Intelligence could make use of the material. Perhaps they reckoned that, by 1943, the war was over, and Britain was at peace ?
You see, when you throw a stone into a pond ............
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Pace our Moderators, as rather off-thread to plug ITV; but, for those who have not seen it, My5's: "Air Crash - Disasters Uncovered" series is well worth a look. Mostly not over-dramatised reconstructions of very well known aircraft accidents. But Season 3, Episode 4: "Fight for your Life" was a new one on me, and had me gasping start to finish.
Just thought I'd mention it .....
Just thought I'd mention it .....
This may solve an old puzzle. Capt. "Winkle" Brown records that he tested a VV (Mk. unstated) and found it useless as an aircraft (which it was). But also said that it was inferior as a dive bomber to the Stuka, in that the VV could not dive vertically (unlike the Stuka), but only at 60-70 degrees. Now we know the reverse is true (for the Mks I and II - US A-31, anyway). Don't know about the Mk.III (also a US A-31), which only came in with the war over. But who is going to gainsay the (late) Eric Brown, the most famous test pilot of all time ? Our esteemed friend "Chugalug" will remember all this .
But if Brown had been given a Mk.IV (US A-35) to test?
But if Brown had been given a Mk.IV (US A-35) to test?
Although of American origin, the Vultee Vengeance owed its existence to the British. It happened like this. The RAF’s Air Staff had been so impressed with the blitzkrieg effectiveness of the Stuka dive bombers, that it decided it must go into the dive-bombing business, and so in 1940 the British Purchasing Commission initially ordered 400 of Vultee’s dive bomber design, the V-72 or Vengeance. Most of these early Mk.I and II aircraft went to the Royal Australian and Indian Air Forces, and the few that came to Britain were primarily for performance and handling assessment.
The USAAF purchased 600 Mk.IAs, Mk.IIs and Mk.IIIs for Lend-Lease and also retained some Mk.IIs for their own operation. A decision to continue purchasing V-72s for Lend-Lease led to some redesign. The zero wing incidence was changed to reduce the aircraft’s nose-up flight characteristics, and the armament changes saw 0.50 in. guns replace the four 0.30 in.wing guns, and a single 0.50 in. replace the two 0.30 in. guns in the rear cockpit. This was designated the A-35A, and 99 were built for the USAAF.
The significance of the different Marks of Vengeance were that the Mk.I was built by Northrop on direct British contract, the Mk.IA by Northrop on USAAF contract, the MK.II by Vultee on direct British contract, the Mk.III by Vultee on USAAF contract.
Further modifications were introduced in the RAF Vengeance IV and USAAF A-35B. Wing armament was increased to six guns, the bomb load doubled to 2,000 lb. and a more powerful version of the Wright Cyclone installed. A simplified fuel system was fitted, together with spring tabs to all control surfaces.
We received Vengeance IV FD2l8 at RAE Farnborough in August 1944 for comparison with other types of dive-bomber we were testing, and also to assess the effects of the design improvements over the Mk.I, which had four major faults, namely poor take-off, bad view in normal flying attitude, a complex fuel system, and heavy out-of-trim rudder foot loads in the dive.
My first impression of the Vengeance was that it was big for a single-engined aeroplane, and its mid-wing had a most unusual planform. The flat centre section had marked sweepback on the leading edges, while the trailing edges were straight. The outer wing panels, which were set at a slight dihedral angle, had straight leading edges, while the trailing edges swept sharply forward to squared-off wing tips. Dive brakes were fitted both above and below the outer wing panels, hinging upwards and backwards, and forward and downwards respectively.
The Vengeance cockpit was in the roomy American style, but instrumentation layout was haphazard with no thought given to rational grouping for the operational task.
The controls consisted of statically and aerodynamically balanced fabric covered elevators and rudder, with controllable trim-tabs in the rudder and port elevator, while the differentially-operated metal ailerons both had electrically operated trim-tabs.
Starting up the Cyclone produced that powerful throaty growl I have always associated with that engine, which in this case drove a Hamilton Standard Hydromatic constant-speed airscrew.
The undercarriage, in spite of its laborious gyration backwards through 90 degrees to lie flat beneath the wings in “bathtub” fairings, retracted remarkably smartly, and the tail wheel partially disappeared into the tail cone. Once the ironmongery was raised and the slotted trailing edge flaps followed suit, the rate of climb became fairly respectable, with stability neutral round all three axes.
At 10,000 ft. I levelled off into the cruise at 215 mph and again stability was neutral. View dead ahead was poorish due to the slightly nose-up normal flying altitude of the aircraft, but the controls were quite well harmonised. Then up to 15,000 ft. to check the stalling characteristics, which were remarkably mild, with slight buffet some 8 mph before the nose dropped gently.
And so to the main objective — to assess the Vengeance IV as a dive bomber. On the run-in a shallow dive is usually entered to build up speed and at this stage the bomb doors are opened, so the higher their permitted operating speed the better. The Vengeance had a high restricting speed of 335 mph thus allowing great operational flexibility in that respect. In the light of the poor view ahead I found it best to approach the target keeping it in sight on either bow until it drew abeam to disappear under the wing tip, and then peel off on to it.
On entering the dive the ailerons on FD2l8 were suprisingly light and the elevator force small, but the aircraft soon started to yaw to starboard and this had to be trimmed out. Speed build up to 270 mph was quite fast, requiring constant directional trimming to avoid skid, but the rudder foot load was light because of the spring tab.
At that speed I popped the dive brakes, which opened rapidly without affecting trim. However, to open the brakes necessitated removing one’s hand from the throttle, as the control was at one’s left elbow. Also the actuating lever had to be returned to neutral after completion of the operating movement.
Terminal velocity with the dive brakes extended was 300 mph and this was also the restricting speed for operating the brakes — a significant operational advantage. Although the elevator force built up progressively after 270 mph it never reached a force that could not easily be held by pushing on the stick without using the trimmer. The yaw to starboard still required constant trimming to avoid skid. Any corrections for line on the target are made by rolling in the dive, and the Vengeance IV’s ailerons remained delightfully light and effective throughout the speed range.
In the actual dive the view over the nose was excellent for the top cowling was flat and smooth, and the front windscreen panel wide enough to accommodate a dive bombing sight without completely obliterating direct vision sectors.
The Vengeance’s natural dive angle seemed to be about 70 degrees, which feels to the pilot more like 90 degrees, and pull-out after bomb release only required a light stick force per ‘g’ so that it was easy for the pilot to black himself out. However, the aeroplane was so highly stressed there was little fear of causing structural damage.
The dive brakes were closed immediately the bombs were released and pull- out commenced, but the bomb doors were only closed on resuming level flight so as to avoid trapping the bomb displacement gear, and their action was very quick thus speeding up the vital getaway.
The whole dive bombing sequence was so efficient with the Vengeance IV that it seems incredible that items such as trimmers should be so inefficiently designed in the cockpit. There was no indicator for the aileron trimmers, that of the rudder a mere electric bulb which lit up when the trimmer was at full nose right setting, while the elevator trim position was crudely painted on a disc above the operating handle.
In my opinion the trimmers for dive bombing should be low geared wheels working in the conventional sense and placed on a level with the pilot’s seat on the left-hand side, and should have pointer indicators marked in degrees of tab setting to each side of neutral.
The internal bomb bay accommodated two 500 lb. bombs, and as overload two further 250 lb. bombs could be carried on external wing racks. This gave the Vengeance a useful punch, which delivered with high accuracy because of the aircraft’s good dive-bombing characteristics, made it a potentially powerful attack weapon.
Surprisingly the Vengeance had a reputation of being somewhat difficult to land, but one must remember that it was being operated mainly in hot and high conditions, and often from hastily prepared strips hewn out of the jungle and of limited dimensions.
Actually the approach speed of 125 mph was quite high, but a lot of speed could be killed off in the last 100 ft. of height before touch down at 105 mph, and indeed the dive brakes could be extended at 10-15 ft. off the ground to give a positive sink on to a three point landing and at the same time act as drag brakes to reduce the landing run. However, once on the ground the view ahead vanished and the pilot had to keep his wits about him to keep straight on a narrow strip on an aircraft with comparatively narrow track undercarriage. I have read a number of pilot impressions of the Vengeance I and the great majority of these are far from enthusiastic, so Vultee did a great improvement job on the Mk.IV, albeit a little late for it to reap the operational benefits.
After the Ju.87, the Vengeance IV is the best dive bomber I have flown. The irony of this aeroplane is that although it was a vast improvement on the previous Marks of the type, only the latter saw operational service, while the Mk.IV arrived at a time when the Air Staff had gone cool on dive bombing, and so it was relegated to the ignominious task of target towing. The early Vengeances earned themselves a bad reputation, and therefore it is a great pity the Vengeance IV was not given a chance to redeem that situation.
The USAAF purchased 600 Mk.IAs, Mk.IIs and Mk.IIIs for Lend-Lease and also retained some Mk.IIs for their own operation. A decision to continue purchasing V-72s for Lend-Lease led to some redesign. The zero wing incidence was changed to reduce the aircraft’s nose-up flight characteristics, and the armament changes saw 0.50 in. guns replace the four 0.30 in.wing guns, and a single 0.50 in. replace the two 0.30 in. guns in the rear cockpit. This was designated the A-35A, and 99 were built for the USAAF.
The significance of the different Marks of Vengeance were that the Mk.I was built by Northrop on direct British contract, the Mk.IA by Northrop on USAAF contract, the MK.II by Vultee on direct British contract, the Mk.III by Vultee on USAAF contract.
Further modifications were introduced in the RAF Vengeance IV and USAAF A-35B. Wing armament was increased to six guns, the bomb load doubled to 2,000 lb. and a more powerful version of the Wright Cyclone installed. A simplified fuel system was fitted, together with spring tabs to all control surfaces.
We received Vengeance IV FD2l8 at RAE Farnborough in August 1944 for comparison with other types of dive-bomber we were testing, and also to assess the effects of the design improvements over the Mk.I, which had four major faults, namely poor take-off, bad view in normal flying attitude, a complex fuel system, and heavy out-of-trim rudder foot loads in the dive.
My first impression of the Vengeance was that it was big for a single-engined aeroplane, and its mid-wing had a most unusual planform. The flat centre section had marked sweepback on the leading edges, while the trailing edges were straight. The outer wing panels, which were set at a slight dihedral angle, had straight leading edges, while the trailing edges swept sharply forward to squared-off wing tips. Dive brakes were fitted both above and below the outer wing panels, hinging upwards and backwards, and forward and downwards respectively.
The Vengeance cockpit was in the roomy American style, but instrumentation layout was haphazard with no thought given to rational grouping for the operational task.
The controls consisted of statically and aerodynamically balanced fabric covered elevators and rudder, with controllable trim-tabs in the rudder and port elevator, while the differentially-operated metal ailerons both had electrically operated trim-tabs.
Starting up the Cyclone produced that powerful throaty growl I have always associated with that engine, which in this case drove a Hamilton Standard Hydromatic constant-speed airscrew.
The undercarriage, in spite of its laborious gyration backwards through 90 degrees to lie flat beneath the wings in “bathtub” fairings, retracted remarkably smartly, and the tail wheel partially disappeared into the tail cone. Once the ironmongery was raised and the slotted trailing edge flaps followed suit, the rate of climb became fairly respectable, with stability neutral round all three axes.
At 10,000 ft. I levelled off into the cruise at 215 mph and again stability was neutral. View dead ahead was poorish due to the slightly nose-up normal flying altitude of the aircraft, but the controls were quite well harmonised. Then up to 15,000 ft. to check the stalling characteristics, which were remarkably mild, with slight buffet some 8 mph before the nose dropped gently.
And so to the main objective — to assess the Vengeance IV as a dive bomber. On the run-in a shallow dive is usually entered to build up speed and at this stage the bomb doors are opened, so the higher their permitted operating speed the better. The Vengeance had a high restricting speed of 335 mph thus allowing great operational flexibility in that respect. In the light of the poor view ahead I found it best to approach the target keeping it in sight on either bow until it drew abeam to disappear under the wing tip, and then peel off on to it.
On entering the dive the ailerons on FD2l8 were suprisingly light and the elevator force small, but the aircraft soon started to yaw to starboard and this had to be trimmed out. Speed build up to 270 mph was quite fast, requiring constant directional trimming to avoid skid, but the rudder foot load was light because of the spring tab.
At that speed I popped the dive brakes, which opened rapidly without affecting trim. However, to open the brakes necessitated removing one’s hand from the throttle, as the control was at one’s left elbow. Also the actuating lever had to be returned to neutral after completion of the operating movement.
Terminal velocity with the dive brakes extended was 300 mph and this was also the restricting speed for operating the brakes — a significant operational advantage. Although the elevator force built up progressively after 270 mph it never reached a force that could not easily be held by pushing on the stick without using the trimmer. The yaw to starboard still required constant trimming to avoid skid. Any corrections for line on the target are made by rolling in the dive, and the Vengeance IV’s ailerons remained delightfully light and effective throughout the speed range.
In the actual dive the view over the nose was excellent for the top cowling was flat and smooth, and the front windscreen panel wide enough to accommodate a dive bombing sight without completely obliterating direct vision sectors.
The Vengeance’s natural dive angle seemed to be about 70 degrees, which feels to the pilot more like 90 degrees, and pull-out after bomb release only required a light stick force per ‘g’ so that it was easy for the pilot to black himself out. However, the aeroplane was so highly stressed there was little fear of causing structural damage.
The dive brakes were closed immediately the bombs were released and pull- out commenced, but the bomb doors were only closed on resuming level flight so as to avoid trapping the bomb displacement gear, and their action was very quick thus speeding up the vital getaway.
The whole dive bombing sequence was so efficient with the Vengeance IV that it seems incredible that items such as trimmers should be so inefficiently designed in the cockpit. There was no indicator for the aileron trimmers, that of the rudder a mere electric bulb which lit up when the trimmer was at full nose right setting, while the elevator trim position was crudely painted on a disc above the operating handle.
In my opinion the trimmers for dive bombing should be low geared wheels working in the conventional sense and placed on a level with the pilot’s seat on the left-hand side, and should have pointer indicators marked in degrees of tab setting to each side of neutral.
The internal bomb bay accommodated two 500 lb. bombs, and as overload two further 250 lb. bombs could be carried on external wing racks. This gave the Vengeance a useful punch, which delivered with high accuracy because of the aircraft’s good dive-bombing characteristics, made it a potentially powerful attack weapon.
Surprisingly the Vengeance had a reputation of being somewhat difficult to land, but one must remember that it was being operated mainly in hot and high conditions, and often from hastily prepared strips hewn out of the jungle and of limited dimensions.
Actually the approach speed of 125 mph was quite high, but a lot of speed could be killed off in the last 100 ft. of height before touch down at 105 mph, and indeed the dive brakes could be extended at 10-15 ft. off the ground to give a positive sink on to a three point landing and at the same time act as drag brakes to reduce the landing run. However, once on the ground the view ahead vanished and the pilot had to keep his wits about him to keep straight on a narrow strip on an aircraft with comparatively narrow track undercarriage. I have read a number of pilot impressions of the Vengeance I and the great majority of these are far from enthusiastic, so Vultee did a great improvement job on the Mk.IV, albeit a little late for it to reap the operational benefits.
After the Ju.87, the Vengeance IV is the best dive bomber I have flown. The irony of this aeroplane is that although it was a vast improvement on the previous Marks of the type, only the latter saw operational service, while the Mk.IV arrived at a time when the Air Staff had gone cool on dive bombing, and so it was relegated to the ignominious task of target towing. The early Vengeances earned themselves a bad reputation, and therefore it is a great pity the Vengeance IV was not given a chance to redeem that situation.
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megan (#12139),
"Wow"- and again "Wow" ! (did not know of the existence of this book, but of course I have got "Wings on my Sleeve"). This is exactly what we have wanted all this time. So many hares have been set running now, that it will take me quite some time to comment on all of them, but I just want to thank you for this priceless find.
This will also be pure gold to Peter C. Smith, who, I understand, has a second edition of his "Vengeance !" (the nearest thing to the "bible" on VVs) on the stocks. I will email him about this book, and take the liberty of copying your quotation to him.
The ripples spread ! Cheers, Danny.
"Wow"- and again "Wow" ! (did not know of the existence of this book, but of course I have got "Wings on my Sleeve"). This is exactly what we have wanted all this time. So many hares have been set running now, that it will take me quite some time to comment on all of them, but I just want to thank you for this priceless find.
This will also be pure gold to Peter C. Smith, who, I understand, has a second edition of his "Vengeance !" (the nearest thing to the "bible" on VVs) on the stocks. I will email him about this book, and take the liberty of copying your quotation to him.
The ripples spread ! Cheers, Danny.
Join Date: Mar 2010
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If this Thread ever developed into “VV Unravelled”,this is the moment!