First, a few sources for others:
Michigan Aircraft Manufacturers, Robert F. Pauley, Arcadia, 2009, page 51
Vintage Airplane,
Mystery Plane, George A. Hardie, Jr., Vol 14 No-3, March 1986, page 26
W.F. Stewart Co. by Mark Theobald, 2004 -
http://www.coachbuilt.com/bui/s/stewart_wf/stewart_wf.htm
en.wikipedia.org
en.wikipedia.org
en.wikipedia.org
Probably nothing here you don't already know but ...
Stewart M-1
The 1928 M-1 was a 4-seat tourer built by the then-new Aviation Division of the Flint, MI-based W.F. Stewart Co. (sometimes listed as W.F. Stewart Mfg. Co.). The Stewart M-1 had twin open-cockpits and a mid-/shoulder-placed cantilever monoplane wing. All-wood construction was employed - making use of W.F. Stewart Co.'s coachbuilding experience. Robert Pauley lists a varnish mahogany covering. Other sources mention spruce spars.
Power was provided by a single surplus Curtiss OX-5 water-cooled V-8 producing 90 hp. Registered X1754 (applied as X-1754), Aerofiles lists an alternative designation of 'X-1' (which Pauley also uses) although this may be conflating with the M-1's c/n - Serial No. X-1. Design was by Lt. John ('Jack') L. Hunt who had been the flying instructor for S. Sidney Stewart, President of the W.F. Stewart Co. According to Pauley, engineering assistance (stressing?) was provided on the M-1 by Lionel Kitchen (which was certainly true for the later M-2).
I'm guessing that the 'M-1' designation simply stood for 'Monoplane Type One'. The M-1's span is usually given as 11.58 m m (although Aerofiles lists 11.76 m), o.a. length was 7.62 m. Can anyone confirm that dual controls were fitted in
both cockpits of the Stewart M-1?
Stewart M-2
In 1930, Sid Stewart instructed 'Jack' Hunt to design a six-passenger cabin aircraft intended as a feederliner. A twin-engined design was specified (partially for superior visibility but mainly to address Stewart's concerns about engine-out climb performance with a heavier trimotor). Hunt developed a high-winged monoplane with twin radial engines underslung below the high wing in pods. Engineering was, again, carried out by Lionel Kitchen. As with the M-1, to suit W.F. Stewart Co. employee skills, construction was primarily of wood.
Sources differ on accommodation. Some sources say six passengers as originally requested by Sid Stewart. Wikipedia (quoting
Skyways 19, July 2000) says four passengers plus pilot. The latter may be confusion with the four-seat M-1 (does anyone know for sure?). The Stewart M-2's span was 16.10 m, o.a. length was 11.28 m.
The sole M-2 was Serial No. 2, with registration X493M (applied as X-493M), was first flown from Bishop Airport (the development of which Sid Stewart also had a hand) by 'Jack' Hunt on 22 May 1931. As first flow, the M-2 had faired but uncowled Wright J-6s. Note that these engines were 300 hp J-6-9 nine-cylinders (Mark Theobald quotes 165 hp, but that was the rating for the five-cylindered J-6-5). At some point, the
Whirlwinds were replaced by a pair of 225 hp Packard DR-980 9-cylinder radial diesels (240 hp for take-off). By 1935, Wright
Whirlwinds had been reinstalled but were now fitted with Townend rings.
After some years in storage, in 1939, the sole M-2 was bought by the Abrams Aerial Survey Corporation of Lansing, MI. The Wikipedia entry claims that Abrams used the M-2 operationally. According to Pauley, Abrams "found it unsuitable for aerial photography". Either way, the Stewart M-2 was broken up for scrap in 1940.