Originally Posted by
dook
Then it must be the S-4B.
Yes: it must be!
The S-4A was assessed by the US Army in 1951 as the YH-24, but failed to be awarded a production contract; not least due to having only a single pilot position which limited its usefulness as a trainer! The S-4B was designed and produced in two months, with side by side seating, as a result of this assessment. The two YH-24s were destroyed by Cessna, who had an involvement in the Siebel concerns.
Over to
dook 