Flying The Vampire
So what is it like to fly the Vampire T11? Matt Hampton,
the VPG’s Chief Pilot, describes a typical sortie:
The
Vampire is a relatively basic aircraft, with good stability
and docile handling – ideal traits for its role as an
advanced trainer. The 'Goblin' engine produces 3,200 lbs of
thrust; even at maximum take-off weight this results in very
impressive performance!
Once
all the checks are complete and the Vampire is lined up on
the runway, the power is smoothly increased to maximum RPM.
The aircraft accelerates rapidly, lifting off at 110 kts.
The undercarriage is retracted and as the speed builds, the
power is reduced to the maximum continuous setting for the
climb.
In-flight
visibility is excellent; the large bubble canopy ensures the
pilots can see in all directions, except directly behind.
The cockpit is quite compact, with everything within easy
reach. As a former training aircraft, the controls are duplicated,
so either pilot can fly the Vampire.
The ailerons, rudder and elevator are all controlled via
cables, with hydraulics used to power the flaps, undercarriage
and airbrake. The controls are well harmonised, but the pitch
control becomes quite heavy at higher airspeeds. A 3 ‘g’
loop requires 4000 feet of airspace above the aircraft, starting
with an entry speed of 300 kts. The speed over the top is
around 130 kts with minimal back pressure required at this
point. Speed builds rapidly again during the ‘downhill’
part of a loop – the Vampire is a slippery aircraft!
The
roll rate is approximately 120 degrees/sec, so a 360 degree
rotation takes 3 seconds to complete and an entry speed of
250 kts or greater is recommended. Wing-overs are large and
graceful, a perfect ‘low stress’ manoeuvre for
both aircraft and passengers!
Deploying
the airbrake produces a light buffet, with no pitch change.
Undercarriage selection also has no appreciable effect on
the aircraft trim; however, lowering the flaps produces a
noticeable pitch up, especially moving from half flap to full
flap.
Stalling in the Vampire T11 is just like stalling a Cessna
or Piper, with the airframe giving you plenty of aerodynamic
warning. Initially there is light buffet, followed by heavy
buffet. If you ignore these signs and continue to pull back
on the stick, the nose drops straight ahead with no tendency
to drop a wing. Recovery is standard; lowering the nose and
increasing the power soon returns the aircraft to normal flight.
Spinning is no longer practiced on the Vampire T11, as although
the aircraft is capable of spinning, recovery must be achieved
by 10,000 feet – not possible without an oxygen system
fitted! It would also subject the aircraft to an unnecessary
risk - spinning has previously resulted in accidents and there
is no point in jeopardising a rare aircraft in such a manner.
Should
the engine fail, making a forced landing is perfectly viable.
The Vampire glides well and ideally a standard pattern would
be flown around a field, using a high key of 4,000 feet and
a low key of 2,000 feet. When certain that the aircraft will
land in the field, gear and flaps may be lowered as required
– resulting in significant extra drag. With full flap,
touchdown takes place at around 95 kts.
Upon rejoining the circuit, the aircraft is positioned downwind,
the speed reduced to 170 kts and the undercarriage is lowered.
At 150 kts one third flap is selected and the power increased
to maintain a speed of 140 kts. Turning base, half flap is
selected and the speed reduced to 130 kts. Turning finals,
the flap is lowered fully; the extra drag causes the speed
to reduce to 105 kts without any power adjustment. On a gusty
day the airbrake is also extended; this requires slightly
more thrust to counteract the extra drag, which makes the
engine quicker to respond if more power is needed.
At
around 5 feet the aircraft is flared; after touchdown the
nose is held off the runway for as long as possible, increasing
the aerodynamic drag and reducing wear and tear on the brakes.
The rudder is effective for steering until below around 60
kts, then differential braking is required.
To summarise, the Vampire is a delightful aircraft to fly
and we hope to keep this particular aircraft in the skies
for many more years!
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