I can't answer for that - but considering the brilliance of Howard Hughes in financial matters, I would be inclined to believe that this would not have been something he would want to have been involved with. Crazy? Possibly. Stupid? Not a chance.
With his past Hollywood connections, the press would have gone bezerk with scandal involving Hughes. And having made his fortune by knowing exactly what he was doing, I am comfortably certain he had at least several back-up plans in case TWA had problems at delivery time. Plan B or C or D or E or who knows was executed in the form of Toolco, the holding company owned by Hughes.
There is also a very good discussion going on here about Hughes and TWA:
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