A newly completed P-38 Lightning rolls out of a hanger at the Lockheed plant in Burbank. I suspect this is one of the first several prototype P38's that were assembled for testing and evaluation. My guess for the date would be in late 1940.
This is the first YP-38, s/n 39-689; c/n 122-2202 @ Lockheed Factory, Burbank, California.
I believe I've seen 2-3 more photos of her in this book.
An interesting article about the fate of the same a/c.
Cheers!