On 12/21/2018 8:46 PM, John Ames via cctalk wrote:
I'd definitely be interested to hear if the DECheads on this list know the specifics, but I'd gathered that it came about once other models were introduced and the need arose to differentiate between, say, a PDP-8/e and a "straight" (i.e. vanilla) PDP-8. The car connection probably made the particular phrasing happen (of course, they originally photographed it in a Volkswagen, but they couldn't very well have started calling it a "flat-4!")
Well your flat 4 can get you a few $$$ as nice little aircraft engine. Happy Flying. Ben.