You have bits and pieces of the story correct. The Langley Twin was an airplane with no Stinson connection at all. It was restored and flying until the late 1960's when it was involved in an accident. If I remember, one of the features of the Langley was that it was all wood. In the ensuing accident the fuselage was broken. This is where the Stinson 108 came in. The owner at the time then decided to use a 108 fuselage and rebuilt the airplane. It looked ok but not as pretty as the Langley.
Stinson did design a twin.....the Piper Apache. That is one of the reasons why Piper bought Stinson. Look at any Piper made in that time frame of 1948-55....they all use Stinson components....window trim, trim cranks, ashtrays, seats, control wheels, etc. I do not believe that Stinson actually made the twin. I have a Popular Mechanics from around 1947-48 describing this twin.
Here is what Aerofiles.com has to say:
Twin (2-4-65/90), NL-1 1942 (ATC 755) = 2-4pClwM; two 65hp Franklin 4AC; span: 35'2" length: 20'8" (?>20'6") load: 985# (?>890#) v: 135/120/50 (?>142/125/46) range: 400 (?>600) ceiling: 13,300' (?>15,000') (disparities are likely between preliminary estimates and actual flight test results, but which are which is unresolved). Arthur Draper, Martin Jensen. The name honored aviation pioneer Samuel P Langley for his early attempts at flight. Take-off in 200'. Second version (aka 29-90) had 90hp Franklin (v: 150/135/55 range: 450). Vidal plastic-bonded mahogany plywood construction. WW2 interrupted production. $8,500; POP: 2 [NX29099, NC/N51706]. The latter went to USN as XNL-1 , then was sold as war surplus. After a crash-landing c.1965, its remains, along with parts of a Stinson Voyager, were rebuilt into an experimental aircraft and renamed Pierce Arrow [N6622A] (no relation to 1926 Pierce Arrow).
There are photos of the airplane on that website.
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