January 1936: build your RAF

[tomo pauk]

Thank you both for effort to post the valuable data

We might want to look at the Short Sunderland Mk.II (data from Wikipedia). Four Pegasus XVIII engines, empty weight of 34,500 lb, 11 crew members. Fuel load of 2,025 imp gals initially, later increased to 2,550, all permanent tanks (Halifax was at 1882 permanent, 2342 with auxiliary tanks, Lanc carried a bit more). Bomb load was lacking, 2000 lbs, but more crew and MGs were carried. Speed was also lacking, 210 mph vs. 280 for the Lanc. Wing area (1,487 ft²)was about the same as of B-17, and some 10-12% greater than for Lanc and Hallifax.

The bomber with 4 Pegasus engines does not need the deep hull (difference vs. Sunderland of at least 2000 lbs?), nor there would be need for 2550 imp gals of fuel for 14-hour patrol missions. 1000 imp gals of fuel less is worth 7200 lbs, plus what ever the tanks weighted (1/2 pound per gallon? - 500 lbs). The bomber will also need a smaller wing, for the same wing loading (less drag and weight). The crew and number of MGs same as what Lanc have had (further less weight and drag); again both smaller fuselage and wing are needed than what Sunderlad had.
So 'my' bomber will be at 30000 lbs empty, 1000-1100 sq ft wing; fuel: 700 (with max bomb load) -1500 (max fuel) imp gals, 6-10000 lbs bomb load, 240-250 mph at 15000 ft.

 

[Shortround6]

Look again at the Y1B-17, maybe they could do a a bit better, but another 15-25mph doesn't change anything.

Please remember that the drag goes up with the square of the speed and actual power required because of the time element, goes up even more.

To get the Y1B-17 up to 282mph (assuming it did the 256mph with 775hp) would require 1030hp according to the cube law.

Lets assume you can shift the wing higher on the Y1B-17 and not get stuck with the real B-17s bomb bay problems. Going very far with 8-10,000lbs isn't really going to happen.

Data card for the Halifax I ;

http://www.wwiiaircraftperformance.org/Halifax/Halifax_I_ADS.jpg

larger, heavier, more power and please note ranges are for most economical speed which is 195mph at 15,000ft. Also please note the difference in Ceiling between max weight and mean weight. Also note the take off distance.

The Halifax II took off in 200yds less distance despite weighing 1,000lbs more, max weight ceiling went up 3,000ft.

I would also note that Wiki (or who ever wrote it) didn't transfer the source materiel quite right for the Sunderland, the 34,500lb weight is tare empty which is a bit different than some other empty weights. tare weight does NOT include such things as guns or radios. Service load (including 11 man crew) was 7060lbs. Petrol (2,155 gallons) was 15,540lbs, oil (100 gal) 900lbs.
The 178mph cruise speed is the MAX economical cruise speed, equivalent the Halifax doing 233mph instead of 195mph. It is also at 5,000ft which means the supercharger is in low gear. Granted the air is thicker and has more drag but the engine is giving about 10% more power to the prop because it is not driving the high speed supercharger gear.
The Sunderland is just so different it doesn't really make a good comparison even it it does use the same engines.

here are some numbers for very early B-24s without turbos, gun turrets, armor or self sealing fuel tanks.

Four Pratt Whitney R-1830-33 (S3C4-G) Twin Wasp fourteen-cylinder air-cooled radials rated at 1200 hp for takeoff and 1000 hp at 14,500 feet. Performance: Maximum speed 273 mph at 15,000 feet. Cruising speed 186 mph. Landing speed 90 mph. Service ceiling 31,500 feet. An altitude of 10,000 feet could be attained in 6 minutes. Range was 3000 miles with a 2500 pound bombload. Maximum range was 4700 miles. Weights: 27,500 pounds, empty, 38,360 pounds gross, 46,400 pounds maximum. Dimensions: Wingspan 110 feet 0 inches, length 63 feet 9 inches, height 18 feet 8 inches, wing area 1048 square feet.

Again from Joe Baugher's website. This for the LB-30A version of the B-24 and it didn't fly until Jan 1941. It used sealed portions of wing for fuel tanks (wet wing, not self sealing) and could not be used for combat. I would also note that both the performance figures here and for the Y1B-17 would much more likely than not, be for the "gross" weight and not the maximum and would more closely correspond to the British mean weight. I mean less than 11,000lbs between empty and gross and the plane is 'supposed' to hold 8,000lb of bombs? take out even 1200lbs for a crew if 6 and you don't have much left for gas and oil.

designers were trying but you just don't get a very useable 4 engine bomber with engines around 1000hp.

Data card from Mike Williams site.

 

[Shortround6]

Bumping this thread as a reply to the question in the "If the RAF had lost the BoB thread...."

about what the British could have done differently to defeat the Germans quicker.

AS with just about every nation, less rivalry between the services would be a good start.
Less empire building and more realistic assessment of of actual needs and capabilities.
That is a bit less of trying to take over from the Royal Navy as the primary Military Force able to win wars on it's own.

There are number of suggestions through this thread.

Better training with planes/weapons they had would have helped and more pre war testing/evaluation of weapons like bombs, mines, torpedoes and guns
might have also paid large dividends, like finding out the 100lb anti-sub bomb was nearly useless and thus the 10 squadrons of Avro Ansons that Coastal Command had in 1939.

A better attitude towards safety of aircraft and air crew could have seen lower operational losses and thus less need for frantic construction of obsolete types and the need for partially trained crews which just made the problem worse.

More later.

 

[Shortround6]

I have harped on the British "reluctance" to adopt the constant speed propeller, especially in it's full feathering version.

It is on WIki so I have no idea how true it is. " Due to wartime shortages, some Beaufighters were placed into operational service without equipment necessary to feather the propellers. As some models of the twin-engined Beaufighter could not stay aloft on one engine unless the dead propeller was feathered, the lack of feathering equipment directly contributed to several operational losses and the deaths of aircrew." this is supposed to be from "The Sky Suspended" by Bailey, James Richard Abe (Jim).

Now if a Beaufighter could not stay in the air on one engine with the dead engine not feathered I wonder at the possibilities of lower powered twin engine aircraft like Beauforts, Blenheims, Wellingtons and the like.
The Lockheed Hudson was called "Old Boomerang" because it supposedly always came back, how true this story is I don't know but it does seem to date back back to around 1942 or before and not be a post war invention.
I don't know if this was because it so rugged or because it came with fully feathering propellers and was much more capable of staying in the air on one engine?

Pilots notes on the Wellington I say "At light load it may be possible to maintain height on one engine at cruising boost and rpm".
Note the words "at light load" and "may be". Now trying flying over water for 2-3 hours like that.
Dead engine should have the prop control set to positive course pitch.
Some British aircraft were fitted with brakes on the propshaft to stop the dead propeller from turning (wind milling) , which is a rather weak substitute. How many scores if not hundreds of air crew were lost due to cheap propellers I have no idea.

21 airlines were using fully feathering propellers in 1939 so it wasn't exactly secret and the benefits were well known and well publicized.