US Navy specification SD 112 : Grumman F7F competition

[Stargazer]

The recent discussion on another SD-112 competition made me realize that there is more to this SD- system than we thought.

SD-112 must have been a basic U.S. Navy specification for a twin-engined carrier-borne fighter, possibly issued in the mid- or late 1920s.

SD-112-14 (1938) produced designs from Brewster, Lockheed, Seversky and others, and led to the Grumman G-34 being procured as the XF5F-1.
Unfortunately, this aircraft proved unsatisfactory.

As hesham pointed out earlier today, the Grumman F7F won the SD-112-18 competition circa 1942, as clearly written on the Bell Model 22 plan.

And so there is a strong possibility here that the suffixes -14 and -18 may have indicated the number of times that the basic specification was modified. Thus the fact that SD-112-14 and -18 were not in sequential order with other SD- specifications of the same time (e.g. SD-220 for the Dauntless).

Any clues or valuable comments/additions to this hypothesis?

 

[hesham]

The Wallace-Martin huff-and-puff...

Hi,

we know Wallace as Stanley Wallace,but who was Martin,was he James V. Martin ?.

 

[Tailspin Turtle]

The Wallace-Martin huff-and-puff...

Hi,

we know Wallace as Stanley Wallace,but who was Martin,was he James V. Martin ?.

The invitation was to the Wallace-Martin Aircraft Corp, 500 Fifth Avenue, New York, NY

 

[ACResearcher]

Re: 3-views for US Navy specification SD 112 : Grumman F7F competition

Newly-drawn 3-views of the aircraft in this competition are to be found in the recently-released "American Secret Projects" from Crecy by Tony Buttler and Alan Griffith.

If anyone plans to scratchbuild one of these I will send them a copy of my drawings, even to the scale your request. However, one aircraft per request, please. I have other books to write and illustrate!

Please contact me at the following email address: acresearcher63@gmail.com

AlanG

 

[Bill S]

I recently found this May 1937 Vought drawing for a two engine fighter V-155A.
Is it possible this was a submission for this same competition?

 

[ACResearcher]

All the submissions I've seen and redrawn for what became the F7F have dates from 1941, so probably not. Even the XF5F/Model G-34 dates from June, 1938.

Do you happen to have a 3-view of it? Looks like something I'd like to redraw.

AlanG

 

[ACResearcher]

I did a little digging in my files and came up with a redraw I did (apparently for "American Secret Projects") of the Vought CVS-4431 V-155B. I also have drawings for the V-155, including Inboard Profiles dated 5-27-37.

HOpefully attached is my redraw of the V-155B 3-view, which the only one I have done.

Enjoy.

AlanG

 

[hesham]

Nice work my dear Alan.

 

[RyanC]

I have a copy of the official memo on this competition and some copies of letters sent out for this competition as a result of a recent visit to NARA II.

The Brewster design was #2 behind the Grumman design. Now there's a alt-hist. ;D given all the delays Brewster was known for...

Twin Engine

#1 Grumman 51 at 74
#2 Brewster 33-D at 61.2

 

[hesham]

Thank you for the Info my dear Ryan.

 

[ACResearcher]

Here is my 3-view drawing of the Brewster 33D entry. This drawing is taken from Tony Buttler and my book "American Secret Projects", available from Crecy and many other online book sources.

Enjoy!

AlanG

 

[blackkite]

Oh American Ki-94Ⅰ.
You mean this book? I must get this book.

 

[ACResearcher]

Exactly right, blackkite!

AlanG

 

[RyanC]

I own a copy. It's a very good start towards the "USAAF 1946" genre.

 

[hesham]

From this book.