The Royal Navy Wasp was similar to the Scout but had
four-wheel landing gear for deck handling. First Wasp HAS. Mk 1 for Royal
Navy flew 28 October 1962, and deliveries began in second half of 1963.
The landing gear was splayed and had heavy shock mounts to ease landing
on pitching frigates and other vessels. The Wasp also had a folding tailboom;
inflatable floatation gear carried in pods that looked like fuel tanks,
mounted on struts alongside the upper fuselage; and featured the folding
main rotor used on the Scout. A total of 245 kilograms (540 pounds) of offensive
stores could be carried under the fuselage, including two homing torpedoes
or depth charges. A few Wasps were configured to carry two SS.11 or two
of the larger AS.12 wire-guided missiles. Development of the naval version
of the Wasp proceeded
more-or-less in parallel, but took longer. The Royal Navy used one of the
prototypes, suitably modified with higher skids suitable for deck landings,
and also ordered two P.531s
powered by Nimbus turbine engines for deck landing and operational trials.
The three aircraft performed exhaustive take-off and landing trials from
the escort vessel HMS Undaunted in November 1959. The definitive Wasp was
mainly intended for ASW from frigates of the Tribal and Leander classes
and similar vessels; for this purpose it could carry one or two 122kg torpedoes
or 250kg of depth charges. In September 1961, the type was ordered for
the Royal Navy under the name Wasp HAS Mk.1 (the first flew on
28 October 1962 with a 968shp Nimbus engine derated to 710shp) and went into
service in October 1963, performing 200 day and night landings on HMS Nubian.