Alongside the four-engined HP.42 (Hannibal class), HP designed a smaller, three-engine airliner that Imperial Airways didn't order, but was reworked as the HP.43 bomber-transport. The sole prototype first flew on 21 June 1932, but was found to be lacking in performance and heavy on the controls. J9833 was extensively rebuilt as a twin-engined monoplane, the HP.51, which led to the HP.54 Harrow. The original caption suggests that this nice photo was taken during the Friday rehearsal for the 1933 RAF Display, but the public don't fit the description of schoolchildren.