I guess you mean "Raiders of the Lost Ark", "Temple of the Doom" was the second one.
There's some toys of that flying wing, you can get it from ebay, they are quite rare though.
I wondered long time ago, actually since I was a kid when I saw for first time Raiders of the Lost Ark, what the heck is that airplane?
Some years ago when I got the Indiana trilogy dvd's (YEAHHHH) I remember when I wondered about that flying wing so I start my research about that thing and the only stuff I found about that was:
Spielberg choosed a flying wing for the movie to represent the andvanced and futuristic german aircraft in ww2, the producer designer Norman Reynolds used a Northrop Corp prototype (which still dunno what prototype was), the film designer Ron Cobb made some drawings to make it look even more unique, the plane was builded at England for Vickers Aircraft Company.
This was one of the early drawings for the movie's flying wing.
Personally I think they picked up the actual blueprints from the N-1M prototype:
But Im also think that the film designer had in mind the Luft 46 Lippisch Li.P04 since the begining.
At the end well as you know, the result was this:
Oh by the way, did you know that Tom Selleck was originally choosed to play Dr Jones role but due he was shooting Magnum P.I tv series, Harrison Ford was selected instead.
Indiana Jones trilogy, one of my favorites movies ever!