Description:
The object of the investigations at Cranfield is to
investigate the effect of water depth, surface roughness —
drainage characteristics and tyre pressure on aquaplaning and
tyre ground friction.
Tests at Cranfield are full scale on the single main—
wheel undercarriage of a Vickers Supermarine Swift F.7. operated
through ponds of water on a test surface. The test area is a
precision surface, level to an accuracy of 1/16" over its entire
width. The levelled area is built into runway 22-04 and consists
of six different surfaces of varying texture, three of concrete
and three of asphalt arranged as shown in fig. 1. The ponds
are constructed of 1 1/2" T section rubber strip affixed to the
surfaces by suitable adhesives which were selected after a series
of tests.
The Swift is fitted with an A.22 recorder giving
traces of port and starboard wheel speeds, obtained by means of
wheel speed generators, and airspeed. A modification is in hand
to record oleo leg extension as a measure of wheel load and
hydrodynamic force.