Martin B-26 Initial Offer

[Clioman]

Was looking through some material at AFHRA today and came across Martin's response to Air Corps Circular Proposal 39-640 (11 March 1939), to which North American also responded (see my related post). Martin's response was GLM Specification #88 dated 1 July 1939 (and revised on 13 September 1939); it described what later became more familiar as the Martin B-26 Marauder, but there were some significant differences...here's the drawing included in that study:

 

[toura]

Hi Clioman
I don't remenber where i've found this

 

[blackkite]

Hi! There are no vertical tail stabilizers in the front view. ???

 

[Nick Sumner]

Do we have any idea what engines were specified?

 

[Jemiba]

Hi! There are no vertical tail stabilizers in the front view. ???

Indeed ! I really have the feeling, that many of those general arrangement drawings were not drawn
to very high standards, But we shouldn't forget, that they in fact still had to be drawn by hand, without
"copy and paste" ! And for us, they often are the only source, apart from perspective views/artist
impressions.
But I would always recommend to check the given dimensions in relation to the drawing.

 

[Stargazer]

I think it has been said somewhere on this forum before, but the Model 179 was initially called the Martian by Martin. The Air Force didn't like it...

 

[joncarrfarrelly]

Martin version of the 3-view, with the inflight sketch, and Summary of Performance chart for R-2600, R-2800
and R-3350 engine options.
- from Deadly Duo: The B-25 and B-26 in WW-II, Charles A. Mendenhall, Specialty Press 1981

 

[Arjen]

From 'Martin Aircraft 1909 -1960' by John R Breihan, Stan Piet & Roger S Mason, Narkiewicz//Thompson 1995.
Model of early Martin 179 configuration.

 

[J.A.W.]

Is it just me, or is that design very like an obese Dornier 217?

Interesting that the Dornier team did better with the performance, weights & loadings measures.

 

[Rickshaw]

Martin version of the 3-view, with the inflight sketch, and Summary of Performance chart for R-2600, R-2800
and R-3350 engine options.
- from Deadly Duo: The B-25 and B-26 in WW-II, Charles A. Mendenhall, Specialty Press 1981

Interesting that they are all radials yet there appears to be no provision for cooling airflow in the drawings.

 

[Abraham Gubler]

Interesting that they are all radials yet there appears to be no provision for cooling airflow in the drawings.

Hole in nose of the spinners. Same concept as the original FW 190 and some other contemporary designs. Didn't work well in practice.

 

[J.A.W.]

Napier seemed to get some good results from the ducted spinner concept, when applied to its Sabre powered Hawkers, if too late for production use - but put the high speed research value towards turbine intake tech.

Dornier however, used the basic BMW radial 801 QEC/power-egg, for their Do 217,
yet eventually found the V12 DB 603 gave better performance numbers, & well in advance of the B-26..

 

[J.A.W.]

& Boeing did of course try Allison in-lines as experimental alternative power-plants in their big bombers..
..with marked improvement in flight performance, ( & looks I.M.O.) like-wise..