Prewar USAAF Doctrine

[buffnut453]

As I remember, most of the B-17s were being sent to the Pacific at that time. The thinking seems to have been send the bulk of the Navy to the Atlantic, Keep a smaller naval force in the Pacific and support it with more air power.

Most of how many? See below for details.

Thats great, so they can launch their operations from their home fields in USA? Building airfields in UK was a massive civil engineering project using up to 60,000 people, I can't see that this civil engineering was ever considered pre war. How many operatioanal squadrons of heavy bombers did the USA have on Sept 3rd 1939?

First flight of the B-17B (the first operational variant) was on 21 June 1939. A whopping 39 B-17Bs were built. Even if we add all those to the totals of prototype variants, we get no more than 53 airframes in the entire US inventory. Of course, I very much doubt that all 39 B-17Bs were built between 21 June and 3 September 1939...but it's possible. However, there wasn't a substantive B-17 force in the USAAF inventory in 1939.

The B-24A didn't arrive on the scene until the summer of 1941 so we can completely exclude that from consideration in 1939.

From what I can find, the B-17Bs equipped the 7th and 19th BGs based at Hamilton Field and March Field respectively (both in California) in 1939.

 

[buffnut453]

In addition to the above, we also have the following bomber types in USAAF service in 1939 (though none were heavy bombers):

B-18 - First flight 1937 and was the most numerous American bomber deployed outside of the continental US at the time of Pearl Harbor. Between 347 and350 built across B-18 and B-18A variants.
B-23 - First flight 27 July 1939 and 38 produced from July 1939 thru September 1940.
A-20/DB-7 - USAAF ordered 186 of these in June 1939 but they didn't enter service until 1940.
Hudson - Was in service with the RAF in early 1939 but wasn't taken into USAAF service until 1941.

 

[Shortround6]

Further US high altitude fighters.

YP-37 with turbo, 13 ordered December 11, 1937 first one delivered in June of 1939. Turbo troubles experiences with the earlier XP-37 continued despite a new turbo model.

Turbo troubles plagued the Bell XFM-1 series.

Last few planes on the production line had the turbos removed before completion.

As mentioned above the US was buying B-17s with turbos with deliveries starting in the summer of 1939.

The First A-20 attack bombers were supposed to have turbos but the first plane had such persistent overheating problems that the turbos were deleted on the rest of the production batch and never came back.

Grumman P-50 fighter was lost when one of it's turbos exploded in flight.

At the 1939 Army fighter trials two entrants were powered by P & W R-1830 engines with mechanical two stage superchargers. Predecessor to the engine used in the Grumman F4F.

The USAAC was very interested in high altitude flight and the technology needed for it. However their experience with it in late 30s lead them to believe it was still several years away from being suitable for service squadron use (and that may have been optimistic) so they ordered the highest altitude rated single stage engines they could get for the P-40 and P-39 to get some sort of modern fighters into service as soon as possible.

The idea that the USAAC was not interested in high altitude fighters is a myth.

 

[tomo pauk]

The idea that the USAAC was not interested in high altitude fighters is a myth.

Bingo.

 

[Akuma]

Most of how many? See below for details.




First flight of the B-17B (the first operational variant) was on 21 June 1939. A whopping 39 B-17Bs were built. Even if we add all those to the totals of prototype variants, we get no more than 53 airframes in the entire US inventory. Of course, I very much doubt that all 39 B-17Bs were built between 21 June and 3 September 1939...but it's possible. However, there wasn't a substantive B-17 force in the USAAF inventory in 1939.

The B-24A didn't arrive on the scene until the summer of 1941 so we can completely exclude that from consideration in 1939.

From what I can find, the B-17Bs equipped the 7th and 19th BGs based at Hamilton Field and March Field respectively (both in California) in 1939.

Just thought I would add the following. 19th Bombardment Group twenty six B-17s to Phillipines, Oct. 1941 joined by nine B-17s of the 14th BG. Source:"They Fought with What They Had.
USAAF officially begins considering and suggesting plans to bomb Japan (along with Pacific Theater Defense) Sept. 1939. Source:"Fortnight of Infamy."