Some unsavoury things he may have been but communist probably wasn't among them.
Quite. One of the first things that happened of a big kind when Wilson was PM was that the merchant seamen went on strike for a pay rise. The claim was modest, and it was clear that British merchant seamen had poor conditions by European standards. Wilson regarded fighting the strike as a matter of national priority. If he was a Communist, he was a bloody devious one; easier to regard him as just devious.
TSR2 was obviously on its last legs, anyway; convenient for the Cons to leave it to the Labs to put it out of its misery. Communists certainly helped kill the British car industry by strikes, but British management was capable of wrecking British manufacturing industry all by itself.
Something that flies well is not necessarily a good weapon, or a good commercial prospect.