Bristol aircraft after the Blenheim

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

To be fair the US was just as bad. The USN and the Army were fighting each other for responsibilies and resources as well. In addition the Army Air Corp was doing everthing possible to gain their independence. Foreign enemies come and go but inter service rivalries are forever.
 
Thumpalumpacus said:
I wonder how they'd hold up under the climate conditions. No doubt they could work from some islands without too much issue, but rain forest is hard on aircraft, even metal, much less wood.
Click to expand...

The first operational squadron to be equipped with Mossies in India was 684 in the PR role at the end of 1943. By the end of the war another 6 squadrons were equipped with the FB.VI and 2 with NF.XIX. They operated throughout South East Asia until the last PR models were retired in 1953. A number of these units traded Beaufighters for their Mossies.

In the early part of 1944 there were some problems with wings becoming unglued that saw the conversion programme suspended for a while. One change that was made with a view to reducing temperatures within the wings, was to paint them in all over silver dope (upper surfaces only on the PR.34). These were never quite fully solved with odd losses occurring in the region and Australia.

By the end of 1946 the last 2 FB squadrons traded Mossies for Beaufighter X, most of which had been in store in the U.K., due to the more robust metal airframe, until in turn replaced by the Brigand in 1949.

Over in Australia 87 squadron RAAF operated PR.40 & PR.XVI from mid-1944 from northern Australia. In May 1945 1 squadron became operational on Morotai with FB.VI but flew few operations before the end of the war before returning to Australia. The final squadron, 94, never left OZ. And of course 618 squadron.

Postwar some Canadian built FB.26 were used in Kenya by 249 squadron during 1946.
 
The biggest user of Packard Merlins was the Lancaster Mk III. The only aircraft that comes close is the P51. In fact almost 1/2 of all Lancasters built were Packard powered. Early Lancaster production used RR built engines but during 1943 Packard Merlins became more predominant. In mid 1943 Packard also had its hands full switching over some of its production to 2 stage engines for P 51s . Good luck getting engines from either of those programs.
 
Last edited:
In March I visited the RAF museum in Hendon, north London. They had the holy Trinity of Bristol twins there, Blenheim, Beaufort and Beaufighter… plus a WW1 era F.2 Fighter. I was most impressed by the Beaufort, imagining what could have been if they'd been on strength in the Indian Ocean when Nagumo neglected to maintain sufficient awareness. The Beaufort seemed bigger though really the Beaufighter isn't much smaller.
 
Last edited:
Admiral Beez said:
Yeah, I think we've established that above. Merlins are definitely out. So, assuming Bristol focuses on engines or other projects, the RAAF needs a Beaufighter replacement.
Click to expand...
Well this is what the RAAF would have got if components from Britain for Beauforts and Beaufighters had dried up in the early war period.

CAC Woomera - Wikipedia

en.m.wikipedia.org

Probably just as well those materials kept flowing!
 
Where does this come from? The Blenheim I was to be modified to the Bolingbroke as an interim General Reconnaissance strike aircraft, but the Bolingbroke was cancelled in December 1937 with the decision to go with the Beaufort as the intended RAF maritime strike aircraft, it could carry a torpedo, a mine or bombs. The other mine laying aircraft was the Hampden. The original Beaufort contract in 1936, off the drawing board, was for 78 aircraft, but two more requisitions in 1938 raised the total to 440, including the RAAF order of 50 (ex Bolingbroke) raised to 90 in August 1938. Then in March 1939 came the decision for 180 to be built in Australia, first 90 RAF, second 90 RAAF (So a total of 440 on order for RAF, 180 on order for RAAF). The next RAF Beaufort orders were in 1940.

The Hampdens had a longer range then the Beaufort, useful for operations off Norway.

I do not have the decision date to go with Beaufighters as torpedo bombers, first production of the TF.X was December 1942, though the first 60 are often labelled mark VI ITF

Coastal Command had the problem over water operations were considered to require flying boats, or at least the theoretical ability to land on water, see the USN and IJNAF for example. Plus the idea France would stay in any war, limiting maritime threats.

Mosquito II DD614 left the UK in September 1942, the RAAF says received in January 1943, but first Australian flight was on 17 December 1942, first flight with Merlin 31 on 23 March 1943. A52-1 first flight was 23 July 1943. A52-2 first flight was in week ending 17 March 1944.

EwenS said:
Australian monthly production numbers from March 1944 were: 2,1,2,1,0,1,2,6,5,7,9,10,11,6,12 total 75 by end of May 1945 rising to 108 on 15 Aug and an eventual 212.
Click to expand...
Add one in June 1944, that is 2,1,2,*2* (or else add 1 in September) as either A52-12 or A52-24 was not counted.

Like Britain Australia could decide to not count aircraft that crashed on test or aircraft diverted to experimental work, sometimes retrospectively, so 212 actually built but many official reports say 209, while the Australian monthly production reports are missing 1 Mosquito, that is they total 211 Three Mosquitoes crashed on test flights, A52-12 on 10 June 1944, A52-18 on 8 November 1944, A52-24 on 21 September 1944. The RAAF card for A52-12 notes it was never brought on charge by the RAAF. Also the cumulative total was officially adjusted down by two in August 1946 as a result of the decision to omit both A52-16 (experimental, became A52-1051) and A52-18. Making the official total 209.

The July 1944 production report stated De Havilland were not happy with the standard of glueing operations in the wings. An investigation by the Directorate of Aeronautical Inspection of the Department of air had resulted in the grounding of all Mosquitoes, but they were back flying by end July. All wings made so far need to be modified. The August report says 17 wings had failed inspection tests. The additional test flight crashes in September and November were further causes for concern, plus probably reading reports from India of the Mosquito glue problems.

The RAAF Chiefs of Staff reports say as of end July 1944 deliveries and acceptance flights delayed pending tests on mainplanes from overseas.

End August that 17 mainplanes already assembled onto aircraft are to be removed for examination

From then until March 1945 the notes include reports of aircraft awaiting or returned to be fitted with new mainplanes or awaiting removal of defective mainplanes.

Week ending 23 March 1945, 13 mainplanes in batch up to No. 168 inspected, 3 satisfactory, 9 needed major repairs outboard of engines, 1 needed repairs over the complete span.

Seems the rejected wings were used as part of the first "whole of structure" fatigue testing.

Beaufighter Mark IC A19-2 ex T4912 was sent to the Australian Department of Aircraft production in February 1943 as part of the plan to build Beaufighters in Australia, it was under test with Cyclone engines in July 1944, I do not have a date for first flight with Cyclones, one photograph dates its roll out as August 1944.

When it comes to Lancasters, With the note there are some small differences between the official sources for mark I and III production totals.
2 UK Merlin and 1 UK Hercules engined prototypes.
UK Merlins, mark I and VII, 3,448 I and 180 VII
US Merlins, mark III and X, 3,016 III and 430 X
UK Hercules, mark II, 300

1941, 18 I
1942, 649 I and 34 III
1943, 287 I, 1,307 III and 16 X
1944, 1,596 I, 1,303 III and 181 X
1945, 896 I, 372 III and 233 X
1946, 2 I

Mark II, 10 in 1942, 254 in 1943 and 36 in 1944. All 180 mark VII in 1945.
 
Well, the Bolingbroke morphed into the Blenheim IV.

It took a while to sort out the Beaufort proposals. These started with the M.15/35 shore based torpedo bomber and the G.24/35 general purpose land based reconnaissance aircraft.
Both got folded into the 10/36.
Not only Blackburn but Avro, Boulton Paul, HP, Vickers and Westland had summitted designs. Granted Bristol Aquila engine and the RR Goshawk appear all to often in the paper proposals.
The Bristol 152 went through a number of changes. According to one book the general reconnaissance version could carry a single 2,000lb bomb, two 500lb bombs or four 250lb bombs. The change for the torpedo bomber role concerned the floor of the body to allow loading the 1900lb torpedo (?).
Supposedly at a late stage in the airframe's construction in the factory the needed modifications would be take to suit the desired armament.
At this stage the choice of engine/s was still the Perseus or the Aquila ( )

The Taurus shows up later. Partly because sanity had prevailed and partly (?) because the requirement had changed and the primary role of bombing required the plane to operate at 15,000ft instead of 5,000ft and fully supercharged engine was required instead of the moderately supercharged engine.
The Botha was stuck with the Perseus engine and the Beaufort got the Taurus but the Taurus rarely got the 15,000ft engine in service versions. This engine change was in 1937 and 1st Beaufort didn't fly until Oct 1938 and the 2nd didn't fly until October 1939 so there was plenty of time to futz around with bomb loads, bomb bays, doors and what not by the time service aircraft showed up.



Note the man on the left may be standing in front of the torpedo horizontal stabilizer and starboard fin/rudder.
Many war time photos do not show the aerodynamic devices that were found to be needed for the higher speed and altitude drops.

The actually need for a torpedo bomber or general reconnaissance (maritime) aircraft to optimum cruise at 15,000ft is certainly subject to question?
Unless it was to keep the planes out of expected AA range when "filling in" as bombers over land?

Remember in 1937-38-39 the number of British engines ( and just about anybody else's) that used two speed superchargers was pretty small.
Basically pick your desired altitude range and then pick the supercharger gear to suit.

Now maybe Tony Buttler is full of it but there was certainly some strange decisions being made in the late 30s.
 
So where were the plans to cancel the 1936 order, plus the additional aircraft ordered in 1938 and 1939? And the Beaufort had a bomb bay that could not take a torpedo, which was carried semi externally.
Shortround6 said:
"The actually need for a torpedo bomber or general reconnaissance (maritime) aircraft to optimum cruise at 15,000ft is certainly subject to question?
Unless it was to keep the planes out of expected AA range when "filling in" as bombers over land?"
Click to expand...
The Beaufort GR design included reconnaissance, flying higher helps spot things, while the then torpedoes limited low level speed requirements to 150 knots.

The Botha was also going to be around as another torpedo bomber. I would have thought the 2,000 pound AP bomb dropped from 15,000 feet would go through most deck armour and given pre war ideas of accuracy be quite dangerous. I am also reminded of the joint Hudson (bombs) Beaufort (torpedoes) strike against Scharnhorst, the Beauforts flew low, the Hudsons high, the groups operating on different radio frequencies, the Hudsons spotted Scharnhorst, the Beauforts did not, but despite attempts the Hudsons could not pass the sighting to the Beauforts, result only the Hudsons attacked. The ability to carry bombs and mines gives flexibility, like being able to attack ships in ports, also there were plenty of smaller ships not worth a torpedo or too shallow draft for torpedoes to be effective. Where is the document stating the Beaufort was initially designed to only carry a torpedo?

See if you can find Naval Weapons of World War II by John Campbell, it is a very good reference.
The mark XI 18 inch torpedo entered service in late 1936, specification was maximum weight 1,500 pounds, able to be dropped at 150 knots from between 30 and 100 feet. Seems 22 were used during WWII probably from MTBs.
The mark XII 18 inch torpedo entered service in 1937, 1,548 pounds weight, the mark XII* was in service in 1939 but at 150 knots dropping speed the torpedo tended to roll. Then came the mark XII**. Used by aircraft and MTBs, All up 1,101 XII used by MTBs and aircraft. Strengthening allowed drop speeds of 250 to 270 knots.
The mark XV was the standard later war 18 inch torpedo. 1,801 pounds, maximum water entry speed 270 knots, however the airborne version cut the warhead from 545 pounds to 388 pounds for wartime torpedo bombers. At the end of the war it was being tested to survive 350 knots and carry the full warhead when dropped from aircraft.

Apart from the Beaufort order the Botha was 242+244 aircraft, contracts from 1936 (became 242+200). Another contract in 1940. So pre war the RAF+RAAF had ordered over 1,000 torpedo capable aircraft. Where are the plans to put Beauforts into Bomber Command units?

Beaufort,
September 1935 M.15/35 torpedo bomber, G/224/35 GR aircraft, both twin engined.
April 1936 Type 152 combining both tasks submitted.
Specification 10/36 issued. 78 ordered in September 1936.
2 November 1936 Bristol proposed changing the Beaufort engine from Perseus to Taurus, accepted in July 1937.
15 October 1938 first Beaufort flight, the first aircraft of the original 78 ordered.

The bomb bay's size, shape and load carrying capacity makes a big difference to a bomber design, not something that can be changed without consequences.

By mid 1940 the mark I was for Beauforts with Taurus II engines, mark II for Taurus III, mark III for Twin Wasp. Later in 1940 or by/in 1941 the mark I was Taurus II, III, VI etc. mark II UK built Twin Wasp, mark III was Merlin, mark IV was Taurus XX, mark V Twin Wasp Australian built. The RAF Contract Cards mostly only refer to the Taurus but details for the first 78 aircraft on contract 552815/36 says 10 Taurus Mk.II and 68 Mk.III. Details for contract 136959/40 say Taurus Mk.II. According to the RAF the Taurus II on the Beaufort was rated at 1,145 HP at 4,500 feet, on the Albacore 1,110 HP at 4,000 feet. The Perseus Xa on the Botha were rated at 935 HP at 5,500 feet. The Cyclone G102A on the early Hudson 900 HP at 6,700 feet. The Taurus II and VI became the XII and XVI.

As for the bombing ideas. The German raids on Britain in WWI dropped around 300 tons of bombs, killing about 1,400 people and wounding about 4,800. The high casualties per bomb was a major input into what WWII bombers were thought capable of. Say 900 German bombers dropping 900 tons of bombs, 4,200 dead, 14,400 wounded, a raid every third day, 42,000 dead and 144,000 wounded per month. Hence in the 1930's it was the bomber gap, versus the later missile and mine shaft gaps. In the 1930's Germany was not trying to match the RN, it was trying to at least match the RAF.

In per division terms the RAF supplied about the same amount of bomber and reconnaissance squadrons for the BEF in 1940 as it did for the 21st Army Group in 1944. In early 1938 the British army was not thinking in terms of sending any force onto the continent, later the upgraded expeditionary force became 2 divisions. In mid 1939 came the idea of sending an army sized unit, but the British Army preparedness then went backwards as conscription was introduced. The next problem is the definition of army support, for the army it was them having control of a large bombing force that hit the front line positions. The RAF at the time thought reconnaissance and some strategic interdiction, key rail centres at key times sort of thing, with any reconnaissance aircraft carrying a few bombs for targets of opportunity. Neither side of the debate was understanding the other, neither had the right doctrine.

The RAF certainly was not interested in the tactical support of armies as defined in 1944, but neither was the army, and given the army was not talking about expeditionary forces until near the start of WWII the RAF actually had quite a sizeable Army Co-operation force. In September 1939 the force came to 13 squadrons, Bomber Command 39 squadrons, Fighter Command 36 squadrons and Coastal Command 19 squadrons.

The 13 Army Co-Operation squadrons
1, 73, 85, 87 Hurricane
2, 4, 13, 16, 26, 614, Lysander
613 Hind/Hector (Obviously not front line.)
53, 59 Blenheim

When the fighting started in May 1940 the RAF had in France, under the Air Component, so meant to support the army, 4 fighter, 5 short range reconnaissance (Lysander), 2 long range bomber reconnaissance and another 2 bomber squadrons with Blenheims. The Advanced Air Striking Force had 2 fighter, 1 strategic reconnaissance and 10 bomber squadrons (8 Battle and 2 Blenheim, ex 1 Group Bomber Command), though the Blenheims were also doing reconnaissance and some in the RAF had visions of the force bombing the Ruhr. They went to France in September 1939, to either bring them within range of Germany (strategic) or to support the army (tactical) depending on how you read the relevant documents. By May 1940 it was understood the Battles would do tactical bombing. While back in Britain a new 1 Group was being formed to replace the Battle squadrons sent to France.

In June 1944, with a much better doctrine, 2nd TAF had 12 bomber squadrons (6 Mosquito fighter bomber, 2 Boston, 4 Mitchell), as well as 8 tactical reconnaissance squadrons (Spitfires, Mustangs) and 9 Auster squadrons, plus 66 fighter/fighter bomber squadrons. There was plenty of things wrong with the RAF doctrine in 1940, but it was providing per ground unit a numerical level of reconnaissance and bomber unit support that was similar to 1944.

A thousand torpedo capable aircraft on order, plus the force sent to France in 1939/40 makes it hard to sustain the idea the RAF was only after strategic bombers or just bombers pre WWII. The "the bomber will always get through" belief meant governments looking at strategic bombers as the main force based on ideas of their effect, but resources were also put into other areas. Reading some of the inter war USAAF discussions about how to use airpower it was striking to see how they were often debating about squadrons and flights, while discussing a large scale conflict that would see groups and commands fielded, expansion allows more specialisation, something that can be hidden in the smaller peace time establishments.

all-aero

all this about aviation, airplanes, helicopters,
www.all-aero.com
 
Last edited:
Geoffrey Sinclair said:
Click to expand...

An excellent article and my congratulations to whoever researched and compiled it but one area remains totally opaque. Who designed the Pratt and Whitney installation on the Aus Beauforts.

The article suggests it was done by Bristol in the UK but also states that CAC offered to do a conversion design.

I had always thought it was a CAC/DAP installation because the first 57 Aus Beauforts used a Hudson firewall forward, including engine mounts, cowls, gills, exhaust, etc, and an adapter structure to mount that on the Bristol wing and nacelle. Except for the accessory gear box installation, the propeller and associated controls, and that the dishpan had an insert where the Hudson oil cooler was fitted it is all Hudson. All the forward cowls (3, 4, 7, 8) are pure Hudson and the rear cowls (4) and carb scoop (1) are pure or modified Hudson. Even the exhaust cover 6 is Hudson meaning the nacelle was designed to use that and the Hudson trough. Cowl 2 is the only cowl that is not Hudson or Hudson based.


The Beaufort Schedule of spare parts shows the adapter structure (or more correctly intermediate structure), which I had expected to have a CAC/DAP part number actually has a Bristol part number which means that Bristol did design the installation using a Hudson powerplant as their pattern. Later Aus Beauforts had the same adapter but a Bristol designed mount and CAC designed cowl gills.
 
I suspect the Twin Wasp design was mostly Bristol with some Australian adaptations. The Twin Wasp Beaufort prototype was N1110 and first flew in November 1940, L1448 first flight with Twin Wasps was in May 1941.

Australian Archives files,
A705 69/19/22 notes two Twin Wasp and accessories were being shipped to Britain in January/February 1940 on Australian account for the twin wasp Beaufort project, with the Australian Prime Minister being involved. Which explains why after the Britsol trials the engines used were shipped to Australia. 1 February 1940, Engine accessories not available until 10 March, Bristol requires 6 months after accessories arrival to complete testing.

MP287/1 368 says N1110 first flight of about 15 minutes on 23 November at 3 pm. Bad weather set in and a petrol pump failed. The early tests were with the SC3G, after which the engines were to be shipped to Australia and S3C4G engines fitted to the prototype along with US propellers to be representative of the mark II being built in Britain.

S3C4G Nose Cowl, Cowl Panels over cylinders and cowl fastenings, Cowl Well to Lockheed Assy.Drg. 163547 R.H., 163550 L.H. SC3G engine the same except for the addition of Air Intakes. "working drawings Cowling Controllable Gills and Exhaust Manifold, Bristol will supply these for both the C3G and C4G engines. The C4G engine will be completed first and Bristol will then revise the design for the C3G" (Dated 25 November 1940)

MP287/1 1501 as of 16 March 1942 says aircraft 1 to 50 "Lockheed Gills with electric motor control" aircraft 51 and later "Catalina Type Gills with hand operated control." "Air scoop for both S3CG4 and S1C3G engines designed on information provided by Pratt and Whitney"
 
Aircraft 58 and later actually had the same part number gills and gill attachment fittings etc as the Boomerang and many of the parts have both Boomerang and Beaufort part numbers cast/stamped in. On the Beaufort the mounting rings are 360 degree but on the Boomerang cropped at the bottom. Part numbers are E180nnn and E3-29nnn. The Boomerang parts are 12-29nnn. To me it is therefore probable that the E180nnn numbers are DAP designed and E3- parts are CAC designed.

The part numbers for the control for the 58 on gills on the Beaufort are all E3- numbers which to me indicates CAC designed but I am not 100% positive. They bear little in common with the Catalina gill controls but none the less could have been partly inspired by them - both use screw jacks but then again so does the UK Mk I - see item X on Fig 14. As you can see on that figure they are also very similar in many ways to the UK Mk I gill controls so I consider it more likely they were an Aus redesign of the Mk I controls - maybe utilizing some features from the Catalina. There were several redesigns -- 58 to 204 used one version, 205 to 392 next and 393 on in the parts list I am currently scanning. It only covers up to aircraft 451 as far as I can tell. It certainly does not cover the Mk VE turret installation fuselage changes or the Ham Std Hydromatic props.

The UK Beauforts had electric gill controls, which may be Hudson or a UK redesign, on all Mk II aircraft.



Mk II


Mk I
 
Correction to my post above where I posted To me it is therefore probable that the E180nnn numbers are DAP designed and E3- parts are CAC designed.

Just found this in the incomplete very poor photocopy (8 1/2 x 13 13 pages copies as A4 with the bottom of most pages missing) DAP Beaufort Division Engineering Manual.

Para 6 covers the DAP part numbers and E1- numbers presumably mean drawings for all Beaufort aircraft - and there are a lot of E1- drawings. Again as a guess E180nnn numbers are E1-8 numbers but that the dash had been deleted somewhere along the way. I cannot remember any E4, E5 etc numbers so that is purely a guess. I will update if I find more. I am still processing the 200 odd pages

 
Okay - I was wrong again

The drawing schedules show there were E18 numbers right from day one and no E5,6,7 numbers. The first is interesting as the schedule matches the Schedule of Spare Parts (parts catalogue to anyone outside the RAF/RAAF and some other Commonwealth countries) and the actual full schedule is almost exclusively Hudson exhaust parts.

P. O. G. M. is power operated gun mount (gun turret to you and I)

There are drawings for an oxygen system that was never fitted to RAAF aircraft - or even the Aus Beauforts built for the RAF.


and right here is where the Blenheim Mk V turret furphy started - that should read Blenheim B1 Mk V turret - a very different animal.
 
You must log in or register to reply here.

Users who are viewing this thread

Total: 1 (members: 0, guests: 1)

Similar threads

Making better Italian aircraft, 1933~1945
2
Replies
32
Views
1K
Shortround6
S
A
1939-1942 FAA: Better aircraft or more aircraft?
2 3 4
Replies
63
Views
4K
Admiral Beez
A
No Blenheim, Beaufort, Beaufighter as we know it - Bristol makes 1-engined aircraft instead?
Replies
8
Views
1K
Shortround6
S
Sten SMG aircraft: productionized aircraft part 2, the what if
8 9 10
Replies
181
Views
11K
z42
Z
C
Advice on wooden aircraft
Replies
3
Views
891
Howard Gibson
Menu
Log in
Register