B-17C/D mass-flights & service dates?

[johnpipe108]

According the the fact sheet at NMUSAF, there were only 18 B-17D aircraft actually made on the Army's order for 42; the balance are reported to have been built as B-17C aircraft and sent to England under "Lend-Lease."

According to what I've read, there were 21 B-17 aircraft in the first mass flight from California to Hawaii; according to Prof. Gordon W. Prange's At Dawn We Slept | The Untold Story of Pearl Harbor, on December 6, 1941, the Hawaiian Air Force held only 12 B-17 aircraft, only half of them flyable (someone apparently forgot that such aircraft require spare-parts to be kept flyable; they undergo serious stress, wear & tear, just by take-off, landing, and airtime, as those of you who really know, really know!). IIRC, one-half were stripped for spares to keep the other half flying.

That would leave 9 B-17 aircraft to fly on in the 2nd mass flight, to the Phillipines, and two mass flights equals lots of the above for those aircraft; I'll bet there were only 4 of those (maybe only 3) flyable by December 7/8, and only 3 were reported to have got off the ground in the Phillipines, and apparently none of the six flyable at Hickam.

I'm wondering which aircraft were what; with the 13 aircraft that flew into the war (after taking off on December 6 at 15 minute intervals), that makes 33 B-17 aircraft total in or over the Pacific on December 6/7. Only 18 of the grand total could have been B-17D, the rest B-17C (AFAIK).

I know that the Swooze is said to be a B-17D, and flew in the first two mass flights, the second of which was reported as May, 1941. The "Handbook of Operation And Flight Instructions For The Model B-17D Bombardment Airplane Manufactured By Boeing Aircraft Company" for the B-17D, of which I have only a copy of the cover-page and page 30 (armament diagram), Technical Order No. 01-20ED-1, is dated October 1, 1941. I'm wondering about this too; was the Army just late in getting a 'D' flight manual published (this may be a rhetorical question, I'm not sure!)?

Thanks for any light you can shed on the subject,

Regards, John

[DryMartini]

John,

They made a typo.

There was an order for 80 fortresses following the B-17B.
38 were completed as B-17Cs, with 20 going to Britain,
leaving 18 for the USAAC.
The remaining 42 were modified, having cowl flaps, a 24V
electrical system, and other changes, designated B-17D.

From the microfilm I have, this is confirmed on the B-17C/D
Fuselage Assembly drawing 65-3421.

-Bill

[aerovin2]

Just to further this discussion, according to Pete Bowers in his Fortress in the Sky (not an infallible source but pretty close), the Air Corps issued a contract on September 20, 1939, for 38 B-17Cs. These were issued Air Corps serials 40-2042 through 40-2079. The deliveries of the B-17C contract was completed by November 1940. Twenty of these B-17Cs were set aside for the RAF.

Contract Change 1 was issued on the original date of the contract (9/20/39) that specified additional equipment that increased the contract price.

Contract Change 2 was issued on April 4, 1940, that ordered an additional 42 B-17Cs with significant equipment changes. These aircraft had serial numbers 40-3059 through 40-3100 assigned.

Contract Change 3 was issued on September 6, 1940, that, due to the significant additional equipment changes, redesignated these aircraft as B-17Ds. The 42 under this contract change were delivered as B-17Ds between February 3, 1941, and April 29, 1941. (The Swoose was delivered on April 25, 1941.)

The B-17E contract was approved on August 30, 1940, and the first delivery on the B-17E contract was on September 27, 1941.

At the time of Pearl Harbor, the Air Corps had accepted (approximately) 185 B-17s as follows:

13 Y1B-17s
1 Y1B-17A
39 B-17Bs
38 B-17Cs
42 B-17Ds
52 (approx) B-17Es