Aero Vintage Books

I have a question about the early Nose turrets on the YB 40 last, B 17 F early B 17 G which were they the Bendix turret from the b 25 b/c? Do you know how many B 17 f/g had the early B 25 Bendix turrets?
I.E. did the b 17 F/g assigned to the 482nd have the early or late bendix turret? Did every yb 40 have the early turret?

SuzyQ194,

B-17G chin turret installations were as follows:

Bendix, GFE (T.O. 11-45AA-3) (no model given) installed in serials 42-31032 thru 43-39480

Bendix Type A-16A installed in serials 43-39841 and subsequent

I think we'll need to find an illustrated parts manual for the YB-40 to answer your question as the YB-40s (42-5732 thru 42-5744) do not fall within either range.

Also, I’ve attached the XB-40 and YB-40 section of the “Model Designations of Army Aircraft” document prepared by the Air Technical Service Command. Doesn’t say much about armament, but thought you might find it interesting.

While we’re on the subject of XB/YB-40s, can you add anything more (you’ve contributed already) to my thread on Yuma-based YB-40s:

https://www.aerovintage.com/forum/viewt ... uma#p10858

Thanks,
Nick

If you have not done so already, I'd suggest a close read of the sections on Bendix turret development contained in the "Development of Aircraft Gun Turrets in the AAF 1917-1944", AAF Historical Study No. 54 issued in June 1947.

Link to the study: https://www.afhra.af.mil/Portals/16/doc ... 29-108.pdf

Page 225 notes that "Washington directed that the surplus Bendix lower turrets [from the B-25] be utilized as chin turrets on the B-17F until the newly designed chin turret could be put into production."

Page 226 notes that "Bendix chin production reached approximately 150 units per month by June 1943, but unlike the experimental model, the earliest production turrets utilized the old indirect or remote sighting system.

Page 227 notes that problems with the adopted remote-sighted early Bendix chin turrets installed on B-17Fs led the "Material Center to dismantle all such turrets installed on B-17F airplanes, and hand-held guns were continued until a production-version direct-sight chin turret could be procured in quantity."

Thanks Scott