The XC-35 was delivered to Wright Field, Ohio in May 1937, made its first performance flight on August 5, and was involved in an extensive flight testing program for which the Army Air Corp [sic] was awarded the Collier Trophy. The lessons learned from the XC-35 played a key role in the development of the Boeing 307 and the B-29 Superfortress which was to be the first mass produced pressurized aircraft. (Van Patten, Robert E., Air Force Magazine Online, Vol.86, No.1 January 2003)
I find it curious that the Army Air Corps was involved in vigorous testing of a model 10 Electra--dual high-priority testing for a technology of revolutionary military and civilian significance; further, that this technology was rolled out eight weeks before AE's flight and then announced a "first performance flight" four weeks after her loss.
Is it possible that Bob Wemple (or someone) modded AE's Electra to a "10-E" not by installing Pratt & Whitney R-1340 Wasp S3H1, 600 hps, but turbocharged Pratt & Whitney XR-1340-43, 550 hps? (Can we tell from existing data whether she used 600s or 550s?)
Would it have been worth testing the turbos on this flight without making any other mods (other than the actual ones necessary to use those specific engines instead of the S3H1s)? I.e. no cabin pressurization, etc., simply an engines test?