Again, a stumper has prevailed with over 500 views and no answers. Here are my answers.
1a. Poland, 1b. PZL, 1c. PZL.30 (or PZL.30BI).
2. 1936.
3. Two Pratt & Whitney R-985 Wasp Junior radials 420 Hp each, for PZL.30.
4. Two Bristol Pegasus VIII radials rated 680 Hp each, 700 Hp each for takeoff, for PZL.30BI.
5. Mixed construction of partly metal stressed skin, steel tube fabric covered, fabric-covered metal and glued wood.
6. Romania.
7. 17 including prototypes-counting the 15 Polish armed bomber version-PZL LWS.6 ZUBR (Bison).
Bonus answer: The German Luftwaffe "appropriated" two of the Bison bombers in 1939, using them as unarmed twin engine trainer aircraft refinished in Luftwaffe colors. (Poland having fallen first to Nazi Germany starting the advent of WWII).
The origin of the aircraft was a twin engine passenger design for the Polish National Airline LOT rife with bad math stress calculation errors and mixed inadequate construction by PZL LWS. This first flown in March 1936. After the prototype with the larger engines crashed with two Romanian officials aboard, the factory covered up by a story that a Romanian had opened a door in flight. LOT then changed their mind and ordered Douglas DC-2 all-metal twin engine 14 passenger commercial transports. Oh, I didn't add- the retractable gear would not retract because of weakness in the main gear retraction mechanism of the PZL taildragger, among other design issues.
PZL.30 BI specs
Crew: Four
Powerplant: Two Bristol Pegasus VIII piston radials 680 Hp, 700 Hp for takeoff.
Speed: Max 236 mph-another source gives Max 212 mph (and more likely)
Length: 50'9"
Height: 13'
Wingspan: 60'9"
Weight: Max 15,135 lb.
Incidentally, one reference called the design "hideous." Any photo of this aircraft welcomed and confirmatory.
