Trevor Jordan, the Kingston Project Office
performance evaluation wizard, recounts some little or unknown Hugh
I believe that Hugh Merewether flew the Hunter faster, higher and further than anyone else.
I was personally involved in establishing the first of these
milestones. Hugh recounted how, during tailplane load tests at high
Mach number in a vertical dive, he had reached an Indicated Mach Number
of 1.17 when, to his great surprise, the reading suddenly increased to
1.35 IMN, clearly without any real increase in speed. Consideration of
the supersonic flow regime, supported by Schlieren photographs from
wind tunnel tests, showed that in these conditions a shock wave spreads
laterally from the wing root intake. It passes over the static ports of
the port wing tip pressure head causing the static pressure to change
from higher-than to lower-than atmospheric pressure, hence the observed
jump in IMN. This occurs at 1.25 True Mach Number - FASTER.
When I was
talking to Alan Gettings, the Dunsfold Flight Development Engineer
covering performance measurement aspects, about Hugh and the above, he
recalled reading an Automatic Observer Panel (AOP) film taken during a
climb-cruise (a flying technique employed to obtain maximum aircraft
range), probably during flight tests connected with increasing the
range of the Hunter. He had noted that Hugh had reached an altitude of
52,000 ft - HIGHER
Finally, when doing some reading in connection with these observations,
I found, in Frank Mason's book 'Hawker Hunter - Biography of a
Thoroughbred' (Patrick Stephens, 1985), an account of non-stop
return Hunter flights from Dunsfold to Turin, with 2x230 gallon drop
tanks, and Dunsfold to Elba with 2x230 and 2x100 gallon drop tanks.
These were followed on 2nd October 1957 by Hugh's proving flight in the
latter configuration to El Adm, Libya, stated to be 1,500 nautical
miles. However, accurate calculations show the distance to be 1,570 nm.
In his 'History of the RAF' Chaz Bower gives the Hunter's range as
1,840 miles (1,600 nm) so the El Adm flight was near the absolute
maximum - FURTHER.
Editor's Note. Trevor's article prompted me to do some reading. Roy
Braybrook in his splendid book 'Hunter' (Osprey, 1987) states, with
reference to Hugh's El Adm flight in XF374: "The straight-line distance
is 1,588 nm but Merewether was forced to fly a dog-leg course of 1,609
nm. The flight took 3 hr 24 min and he landed with 450 lb (fuel)
remaining. It had been a fairly marginal exercise..." !
MJ Hardy's 'Hawker Hunter Super Profile' (Foulis, 1985) gives the range
of the Hunter F.6 as 1,854 miles (1,612 nm) with two 230 Imp gal and
two 100 Imp gal drop tanks.
So, whichever way you look at it, Hugh got as far as you can get.