Not trying to get into arguments, but the Vanguard was designed and built as a 3 man crew airplane. TCA did not want to utilize a 3rd crew member so they covered over that part of the overhead panel that was accessible by the 3rd man and removed the seat. Later, a few instruments were exposed so they could be read 'inflight'. It was flown by two pilots for the time it was in the company, not by design but by desire!
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