1946: the Republic Aviation Company announces a commercial plane that will never get built

In 1946 with the first flight of the Republic XF-12 Rainbow, an all-metal prototype reconnaissance aircraft, the Republic Aviation Company also announces a commercial version, that was planned to be sold  American Airlines and Pan-Am. But, as those two companies canceled their order and without military orders subsidizing development and tooling costs, the project was scrapped before any prototype was built.


Excerpt from the presentation:

Republic Rainbow. Fastest passenger transport, the 51-ton Rainbow can carry 46 passengers from coast to coast in slightly over six hours, at a ton-mile cost of 12.5 cents. Externally identical with its military prototype, XF-12 (image above), the Rainbow will cruise at more than 400 m.p.h. at 40,000 feet. Comfort is assured by pressurized cabin ,aintaining 8,000 foot atmosphere, ample lounge, smoker, and buffet accommodations. Power comes from four Pratt & Whitney engines developing 13,000 hp. Jet thrust assist, utilized commercialy for the first time, adds 200 hp. per engine at high altitude as the exhaust gases rush from the elongated nacelles. Rainbow is 100 feet long with 129-foot wing spread. Range is 4,100 miles with full load.