In 1939 Boulton & Paul built a twin-engine
all-metal biplane under a contract awarded by Imperial Airways. The
airline had a requirement for a mailplane capable of carrying a 1,000 lb
(454 kg) payload over a 1,000 mile (1609 km) range at reasonable speed,
and the company considered its Boulton & Paul P.64 Mailplane to be the
answer. Unfortunately it was both expensive and unsatisfactory. First
flown at the company's airfield at Mousehold, Norwich, in March 1933, it
lasted barely seven months before being destroyed in an unexplained fatal
crash during trials at Martlesham Heath in October.
Development of the basic layout was
continued, and the resulting Boulton & Paul P.71A was lighter, slimmer and
longer. In place of the 555 hp (414 kW) Bristol Pegasus engines of the
P.64, the P.71A had 490 hp (365 kW) Armstrong Siddeley Jaguar VIAs, and
two aircraft were delivered to Imperial Airways at Croydon in February
1935.
By then, the airline had lost interest in the mail-carrying possibilities
and the two aircraft, named 'Boadicea' and 'Britomart', were converted for
passenger carrying with 13 seats. As VIP transports they had seven seats,
which were easily removable if the aircraft were required for use as light
freighters.
The P.71As were both lost within 19 months of delivery. The first of them
was damaged beyond repair in a landing accident at Brussels in October
1935; the second disappeared over the English Channel in September 1936
Power Plant: Two 490 h.p. Armstrong Siddeley Jaguar VIA
Span: 54 ft 0 in
Length: 44 ft 2 in
Weight (All-Up): 9,500 lb
Cruise Speed: 150 m.p.h.
Range: 600 miles
Crew: 2
Passengers: 7