Like any US-American aircraft produced by a big manufacturer, and Bell was one, the XP-77 is well documented on the internet. There is a Wikipedia article, https://en.wikipedia...wiki/Bell_XP-77 and more telling, something from retromechanix.com, http://retromechanix...ell-xp-77-1944/.
So what to learn about the XP-77? For an US-American aircraft, it shows some uncommon features. The USA are a big country, and their output of aircraft is also connotated with largeness, like Thunderbolts and Superfortresses. Contrary to this, the XP-77 is a very small aircraft.
What everybody sees, but maybe many people are not aware (I was not before reading it in Wikipedia), the XP-77 shows the configuration of a 1930s midget racer. So we can assume the XP-77 is the effort to convert the midget racer into something fight-worthy.
The other thing is, you may expect from such a concept it may outrun, outturn and outclimb a much heavier enemy fighter, e.g. the Mitsubishi Zero. But what you can not assume of it is: range. So the XP-77 is a purely defensive concept, probably born from the idea the US themselves may get under pressure in a subsequent phase of WWII. It looks like being an "US people's fighter" concept, with every patriot mechanic keeping one in his backyard. So, as there is no Sitka spruce wood found in the grasslands of Kansas, for "hommade production" this needed to be stored there before Alaska fell in Japanese hands.
But what we have seen already by looking at the promising Ambrosini fighters, no aerodynamic concept is good enough to overwhelm drag created at high speeds in a way that no high-performance engine is required. For to run about 700 kph, the XP-77 needed an engine of about 1,200 hp, so no real manufacturing advantage would be achieved by this concept.
So I think we don't need to assume the Bell engineers missed a chance in the XP-77. By trial, they tested the concept for being profitable. By error, they found out it was not. Anyway, the XP-77 claims the unique position of a midget concept within a giant's war industry.
Now, let us look on some nice pictures:
#1: From Dan Shumakers's collection:
#2: You see they are from retromechanix.com but not obtainable there. I got this and the following one from the magnificient P_D_M blog, http://p-d-m.livejournal.com:
#3: See #2.
#4: From the Flick account of *Aerofifties*:
#5: This and the following two from the *Batman 60* Flickr account, from whom you enjoy here already some fine pictures:
#6: See #5. Makes one think the P-77 might also have served as parasite fighter for the B-29 (wingtip coupling?).
#7: See #6.
#8: Fine graphics from World of Warplanes:
(need more enrtries to continue with the pictures)