Bristol aircraft after the Blenheim

[tomo pauk]

Same drill as with similar threads: once they have contract for the Blenheim (September 1935), what kind of aircraft Bristol should've been designing and producing? For the upcoming war, and up until ~1955 when the Mach 2 is the next 'target' for the aircraft-producing companies. Engines of the day (you can axe something to speed up a bit something else, within reasonable boundaries), aerodynamics of the day. Ditto for materials, guns, other weapons and electronics.
Upgrading the Blenheim is also okay.

 

[Howard Gibson]

In 1940, the deficiencies of the Blenheim were that it was too slow, and its defensive armament was ineffective. Bigger engines, a narrower fuselage and deletion of the turret all were good ideas, leaving us something that would look a lot like a Beaufighter.

I am looking up alternate engines for the Blenheim and the Canadian made Bolingbrokes. Canadians tested P&W Twin Wasp Juniors (R-1535). The Hercules does not seem to have been considered.

The Blenheim was to be replaced by the Buckingham, with two Centaurus engines. This was first flown in 1943. They did 330mph at 12,000ft, and offered no advantage over a Mosquito. The aircraft had a dorsal turret, and a Luftwaffe like ventral pod. I believe they worked out that a turret would take 60mph off the top speed of a Mosquito. Delete the stuff sticking out, and it may have had the same top speed as the Mosquito. It's bomb load was 4,000lb, substantially more than most Mosquito variants.

If Bristol could not get Centaurus engines into service, could they be persuaded to use somebody else's engine, like the Double Wasp? These were used on most of the Vickers Warwicks. It might have been a good way to soup up Beaufighters, although there are some obvious political issues.

 

[tomo pauk]

If we need a 2000++ HP engines to make performers, perhaps it is the airframe division that needs to update?

 

[Howard Gibson]

If we need a 2000++ HP engines to make performers, perhaps it is the airframe division that needs to update?

We need 2000++HP engines to make performers in mid-WWII.

We could pull a Mitsubishi and get 300mph plus out of the Blenheim, but the resulting aircraft would be delicate. There is no free lunch. Could the Blenheim's airframe handle a bigger engines and 350+mph performance?

 

[tomo pauk]

We need 2000++HP engines to make performers in mid-WWII.

We could pull a Mitsubishi and get 300mph plus out of the Blenheim, but the resulting aircraft would be delicate. There is no free lunch. Could the Blenheim's airframe handle a bigger engines and 350+mph performance?

Bristol's resources are far better spend on making brand new aircraft than trying to make Blenheim go 300 mph.

 

[Shortround6]

Bristol's resources are far better spend on making brand new aircraft than trying to make Blenheim go 300 mph.

You could make a Blenheim do 300 without too much trouble. Assuming you had a decent engine and by decent even a P & W R-1830 should do it.
Martin Marylander did 304mph at 13,000ft using 1050hp take-off engines.

The Blenheim was a small aircraft, yes it had a 469sq ft wing but the MK I was supposed to weigh about 8,100 empty and 12,500lbs loaded.

Problems came in when the MK IV went to around 14,400-14,500lbs with no real increase in power. The MK IV also tended to grow some rather large add ons.

The MK V porked up to 17,000lbs or more. The use of 100 octane improved speed down low but did nothing for speed in the mid teens.

A Beaufort I went 21,000lbs and the Beaufighter went over 25,000lbs.

The Buckingham wound up with a 708 sq ft wing and weighed 24,000lbs empty and 34,000lbs loaded (well within Martin B-26 range)/
There was a Bristol 162 project using Beuafighter rear fuselage and tail and outer wings?

The 162 is the near mock up assembly.

A rather less ambitious aircraft would use the Beaufort wing (and landing gear) on a skinny fuselage closer in size to the Blenheim and using R-1830 engines since the British have nothing that would work. You can't power everything with Merlins

 

[tomo pauk]

You could make a Blenheim do 300 without too much trouble. Assuming you had a decent engine and by decent even a P & W R-1830 should do it.
Martin Marylander did 304mph at 13,000ft using 1050hp take-off engines.

The Blenheim was a small aircraft, yes it had a 469sq ft wing but the MK I was supposed to weigh about 8,100 empty and 12,500lbs loaded.

Problems came in when the MK IV went to around 14,400-14,500lbs with no real increase in power. The MK IV also tended to grow some rather large add ons.

The MK V porked up to 17,000lbs or more. The use of 100 octane improved speed down low but did nothing for speed in the mid teens.

Blenheim was not a small aircraft IMO. Yes, initially it was a light A/C.
Past Mk.I, both weight and drag went up by a very large margin indeed.

A Beaufort I went 21,000lbs and the Beaufighter went over 25,000lbs.

Beaufort really required Hercules engines from day one.

A rather less ambitious aircraft would use the Beaufort wing (and landing gear) on a skinny fuselage closer in size to the Blenheim and using R-1830 engines since the British have nothing that would work. You can't power everything with Merlins

My 'less ambitious Beaufort' would've probably been powered by Pegasus engines. Talk British equivalent of Do 17Z, available in 1938.

 

[Shortround6]

Blenheim was not a small aircraft IMO. Yes, initially it was a light A/C.
Past Mk.I, both weight and drag went up by a very large margin indeed.

• Crew: three (pilot, navigator/bomb aimer/gunner, and radio operator/gunner)
• Length: 46 ft 8 in (14.2 m)
• Wingspan: 61 ft 4 in (18.7 m)
• Height: 16 ft 3 in (5.0 m)
• Wing area: 537 sq ft (49.9 m2​)
• Empty weight: 10,586 lb (4,802 kg)
• Gross weight: 15,297 lb (6,939 kg)
• Max takeoff weight: 16,809 lb (7,624 kg)
• Fuel capacity: 514 imperial gallons (2,336 litres)
• Powerplant: 2 × Pratt & Whitney R-1830-S1C3-G "Twin Wasp" radial engine, 1,050 hp (783 kW) each
• Propellers: 3-bladed Hamilton Standard 3T50 constant-speed metal propellers, 10 ft 11 in (3.3 m) diameter

Performance

• Maximum speed: 304 mph (489 km/h, 264 kn) at 13,000 ft (3,962 m)
• Cruise speed: 248 mph (399 km/h, 216 kn)
• Range: 1,300 mi (2,100 km, 1,100 nmi)
• Service ceiling: 29,500 ft (8,991 m)

It's Wiki, take range and ceiling with a dose of salt.

From Joe Baugher. Between December 1940 and April 1941, 150 Maryland IIs were delivered to the RAF with R-1830-S3C4-G Wasps which were each rated at 1000 hp at 12,500 feet."
The Maryland Is had 900hp at 12,000ft.

Wiki bomb load is rather generous. .
French used two 624-pounds or eight 116-pound bombs and six 7.5-mm machine guns

It seems several air forces wanted higher cockpits for better view over the cowls and engines. I don't know it they really needed to be as high as the Beaufort and the Baltimore.

The Buckingham bulked up when the desired bomb load went to "The bomb bay could hold a 4,000 lb, two 2,000 lb, four 1,000 lb or six 500-lb bombs"
A super Blenheim might have been quite doable as long the bomb load remained in reason (2000lbs or under) and some of the other things, like guns and range also didn't show much of change.

Beaufort really required Hercules engines from day one.

Probably but then you were going to need a bigger plane. Or something taken out (less range?) or something????
The Beaufighter only became a torpedo bomber with the almost 1600hp Hercules. Would the RAF have accepted a 2 man aircraft prewar for the torpedo bomber role or would they have insisted on 3-4 men? And with the big fuselage what happens to the speed even with Hercules engines?

 

[Admiral Beez]

If Bristol could not get Centaurus engines into service, could they be persuaded to use somebody else's engine, like the Double Wasp?

As superlative as the Beaufighter was, engine development and expediting introduction of the Hercules and Centaurus is where Bristol should have been focused after the launch of the Blenheim, rather than aircraft design and production. Daimler-Benz, Rolls Royce, Pratt & Whitney, Mikulin, Shvetsov, etc. knew that their greatest contribution to the war effort was engine development and prosecution, rather than aircraft. Some firms try to do both, such as Junkers, Curtiss, Mitsubishi, Armstrong-Siddeley and Bristol, but I suggest pursuing either engines or aircraft may be better. Hispano-Suiza understood this, and moved from aircraft and engine design to solely engines by the mid 1930s.

So, Air Ministry instructions to Bristol after Blenheim first flies in 1935: stop aircraft design. No Beaufort or Beaufighter, for example. Get us more and more powerful engines, pronto.

 

[Thumpalumpacus]

As superlative as the Beaufighter was, engine development and expediting introduction of the Hercules and Centaurus is where Bristol should have been focused after the launched of the Blenheim, rather than aircraft design and production. Daimler-Benz, Rolls Royce, Pratt & Whitney, Mikulin, Shvetsov, etc. knew that their greatest contribution to the war effort was engine development and prosecution, rather than aircraft. Some firms try to do both, such as Junkers, Curtiss, Mitsubishi, Armstrong-Siddeley and Bristol, but I suggest pursuing either engines or aircraft may be better. Hispano-Suiza understood this, and moved from aircraft and engine design to solely engines by the mid 1930s.

So, Air Ministry instructions to Bristol after Blenheim first flies in 1935: stop aircraft design. No Beaufort or Beaufighter, for example. Get us more and more powerful engines, pronto.

On an intellectual level, you're right, but man, no Beaufighter just hurts my heart. And they'd be sorely missed at Bismarck Sea where they did such a great job.

 

[Admiral Beez]

On an intellectual level, you're right, but man, no Beaufighter just hurts my heart. And they'd be sorely missed at Bismarck Sea where they did such a great job.

Get the RAAF Packard Merlin powered Mosquitos and all will be forgiven.

 

[Thumpalumpacus]

Get the RAAF Packard Merlin powered Mosquitos and all will be forgiven.

Like the RAF will go for that!

 

[buffnut453]

Given the operating conditions in the Far East, I'd prefer Beaus over Mossies...and I'm a HUGE Mossie fan.

 

[tomo pauk]

Probably but then you were going to need a bigger plane. Or something taken out (less range?) or something????
The Beaufighter only became a torpedo bomber with the almost 1600hp Hercules. Would the RAF have accepted a 2 man aircraft prewar for the torpedo bomber role or would they have insisted on 3-4 men? And with the big fuselage what happens to the speed even with Hercules engines?

We already have a big plane. What was also big was the G load, that made possible a quick switch to the Beaufighter that had a lower G load than the Beufort. So I'd trade the G load for the Hercules engines. We can start adding some fuel later, like it was the case with Beaufighter (that went from 540 to 682, even when carrying the heavy Mk.13 torpedo), but already at 570 imp gals the Beufort was one rangy aircraft.
Unless the RAF changes the requirement down to 2-3 men, fuselage will remain as-is. Speed will be no worse than with B-25, once 2-speed supercharged Hercules are installed? With 1-speed supercharged engines, we'd see perhaps 20 mph gain vs. the Taurus-powered Beauforts.
Bristol was not renown for making low-drag aircraft.

 

[ThomasP]

Maybe not quite to the OP, but how about a detail improved HP Hampden made by Bristol?

The Hampden airframe already had the ability to carry upto 4000 lbs of ordnance internally, and the original design allowed for the option of the Merlin being fitted.

 

[tomo pauk]

Maybe not quite to the OP, but how about a detail improved HP Hampden made by Bristol?

The Hampden airframe already had the ability to carry upto 4000 lbs of ordnance internally, and the original design allowed for the option of the Merlin being fitted.

Having Bristol make Hampden under licence gets my vote, too.
Plus, the Beaufighter can be a clean-sheet design now.

 

[Admiral Beez]

Like the RAF will go for that!

Too bad for the RAF. Both Canada and Australia produced the Mosquito - so they'll take what they need from their domestic production. The first Canadian Mosquitos were completed in Sept 1941.

The first Australian Mosquito was produced in July 1943, totally 212 aircraft built at Bankstown. I see no reason the Australians can't follow the Canadian example and start earlier in time to replace their lost Beaufighters. Getting Packard engines may be logistically tricky, but any transports from the US West Coast bringing engines to Australia can sail freely until Dec 1941, and then stay well south afterward.

 

[Admiral Beez]

Maybe not quite to the OP, but how about a detail improved HP Hampden made by Bristol?

The best improvement Bristol can make to the Hampden is more horsepower. That's got to be their focus. Stop making planes, get the damn engines reliable and delivered faster. First Bristol Hercules runs in Jan 1936, but doesn't enter service until mid-1939, and not in wide service until 1940. The first Centaurus is run in July 1938, but doesn't enter wide service until the damn war's over. What the hell Bristol?

Someone should have told Bristol to shelve the sleeve drive idea, pursue a fast to produce, sodium-cooled, easy to maintain two row, 18 cylinder variant of the Pegasus instead.

 

[Thumpalumpacus]

Too bad for the RAF. Both Canada and Australia produced the Mosquito - so they'll take what they need from their domestic production. The first Canadian Mosquitos were completed in Sept 1941.

The first Australian Mosquito was produced in July 1943, totally 212 aircraft built at Bankstown. I see no reason the Australians can't follow the Canadian example and start earlier in time to replace their lost Beaufighters. Getting Packard engines may be logistically tricky, but any transports from the US West Coast bringing engines to Australia can sail freely until Dec 1941, and then stay well south afterward.

Did America have the output numbers for the Merlin to provide them?

 

[Admiral Beez]

Did America have the output numbers for the Merlin to provide them?

I don't know, but Packard had enough to power all but the earliest units of Canada's CC&F Hurricanes and all of its production of DHC Mosquitos and Victory Lancasters.

If there is no Beaufighter, Australia still has the need. The Mosquito would do nicely.