Thermals are columns of warm rising air, and are triggered
by areas of ground that are warmer than their neighbours. For example,
a brown ploughed field often warms up in the sun more quickly than
the grass field next to it. Thermals are often marked at the top by
Cumulus
(or "cotton wool") clouds. They can occur anywhere, and
are the commonest source of lift.
Because the thermals are columns of rising air, gliders need to
circle to stay in them.
Ridge Lift is caused by wind blowing towards a steep ridge,
such as Sutton Bank in Yorkshire.
The wind blows up the face of the hill, and is still rising some
distance above the top of the ridge.
Gliders flying in ridge lift tack to and fro along the ridge to
stay in the lift.
Wave occurs higher in the atmosphere, and is caused by
the wind blowing over high hills or mountains. There is a series
of standing waves downwind of the mountains, like the ripples
behind a rock in a stream. Wave is marked by bands of lenticular,
or lens-shaped, cloud.
Gliders flying in wave fly along one side of the wave clouds
like surfers, and can travel long distances in a straight line.
They can also fly very very high in wave.
Snitterfield is in a very flat part of the country, so there
is no ridge lift, and we only very occasionally get wave from the
Black Mountains in Wales. There are, however, plenty of reliable
sources of thermals close to the airfield, so there's no problem
finding that important first thermal on a good day.
How Does a Glider Take Off
Gliders are usually launched by a winch or towed behind a light aircraft.
A Winch is powered by a large engine, and pulls
a cable which is as long as the airfield. The launch height is
typically between 800' and 2000'.
An aerotow uses a light aircraft to tow the glider into the air,
and the launch is usually to 2000', although it can of course
be to any height if the pilot is prepared to pay the extra fees.
An aerotow can take you to a known source of lift, or to any height,
and so is an easier way to start the flight. However, the winch is
much cheaper and more cost effective. At Snitterfield, we only use
the winch, and our launch height is usually between 1300' and 1800',
depending on the weather conditions.
On a good day, there are enough thermals in easy range of the airfield
to make it just as good as an aerotow.
How Long, How High, How Far
A glider can stay airborne for as long as the weather is working
in its favour. One of the gliding certificates, which most
experienced pilots have achieved, requires a five-hour duration flight.
Long-distance cross-country flights can easily take five, six,
or even eight hours. When you're learning, though, even twenty
minutes is a long time, and can be quite difficult to achieve.
Thermals in Britain reach cloudbase at typically 4000' to 5000' on a
reasonably good day, although 6000' is not uncommon and 8000' is not
unknown. In wave, though, 20,000' is quite common for pilots using oxygen,
and much greater heights are possible for pilots with the right equipment.
Pilots who fly cross-country usually fly a triangular course, visiting two
pre-declared turning points and then returning home. This course may be
100km for a beginner, or up to 300km or even 500km for an expert.
The longest flight from Snitterfield was 751Km to Petersfield, Lincoln,
Basingstoke, and home, which took Phil King and Martyn Davies, flying
in two single-seaters, over 9 hours.
The previous CFI at Snitterfield, Dave Benton, holds a British height gain
record with a flight to 38,200' in Scotland in 1982. The British distance
record is just over 1000km, a flight in a two-seater which took over 12
hours. The world distance record is over 3500km, in the Andes, and took
over 15 hours.
On March 3rd 1999, Jim and Tom Payne, flying an ASH-25 in California, broke
the world record for a 300K out-and-return: 1 hour 7 minutes,
269Kph! That was in the morning. In the afternoon, they did a 500K
out-and-return in 2:02, 247Kph. Apparently, the wave lift was quite good.
Most pilots, it has to be said, are quite content with much less than this.
Who Can Be a Glider Pilot
Almost anybody. You can't fly solo until your sixteenth birthday, so
we normally don't start to teach
youngsters
much before this. If you're over seventy, the medical requirements make
it impractical to continue to be an instructor.
If you are particularly
large or small,
we may not have a glider that fits you.
Between these limits, almost anyone can fly. We have members who started
to learn after they retired at 65, and members who went solo on
their 16th birthday.
The level of ability required is similar to that needed to drive a car, so
almost anyone can do it. There are very few people who seriously try to
learn to fly, but who fail to reach solo standard.
In particular, there is no advantage in being male, and many instructors
think that women often make better pilots. Nevertheless, only about 15% of
our members are women, an imbalance that we would very much like to correct.
We have two
Disabled Pilots,
and many disablities
do not preclude flying solo. Each case must be decided on its merits, and
safety is the only issue. Anyone who has sound senses and a sound upper
body can fly a glider, and control rather than strength is the main
requirement.
How Do I Learn to Glide
If you want to learn to glide, the only way to do it is to
join a club and fly regularly.
If you want to find out if you want to learn to glide, there are plenty of
ways to go about it. The easiest is to give the airfield a call on 01789-731095
to make sure that we're flying that day, turn up at Snitterfield, and ask for a
Trial Lesson.
You'll get a
briefing and a trial flight, and 28 days membership of the Club. If you
explain that you're thinking of taking up the sport, you'll get a lot more
information about flying in general, and the Club in particular, than the
visitor who's just come along for a bit of fun.
If you want to try more than just a flight, we can arrange a day's
flying, or a proper five-day
Course.
This is plenty of time to learn to fly, although there are airmanship and
judgement considerations that will probably mean that you won't fly solo.
However, if five days isn't enough to find out whether gliding
is for you, then it probably isn't.
Is Solo The End Of It?
No, solo is just the beginning.
Once you've gone solo, you'll undergo a period of supervised solo flying,
and then you'll start working towards your Bronze 'C' Certificate.
The Bronze includes written exams and tests of your flying, airmanship, and
cross-country ability. When you've reached Bronze standard, you are free to
fly solo cross-country, which is the aim of most pilots. At this stage,
most people are thinking about buying a share of their own aircraft.
It's possession of the Bronze that marks you as a Real Pilot.
The Silver 'C' Certificate is a certificate of cross-country achievement.
There are three legs: a 1000m climb, a 5-hour duration flight, and a 50km
cross-country flight away from home. The Silver is within the ability of
almost all pilots flying almost any aircraft.
After the Silver are Gold and Diamond, which require 300km/500km flights
and 2000m/3000m climbs. These require the necessary conditions,
high-performance aircraft, and high-performance pilots, so they are
not an automatic progression.
Alternatively, but not mutually exclusively, are the dual flying ratings:
P1, Passenger Carrying;
BI, Basic Instructor;
Assistant Category Instructor;
Full Category Instructor.
The instructors that you fly with were once novice pilots like yourself,
and most of them started flying at Stratford.
What Are The Rewards
The rewards are what you make them. Some pilots are happy soaring locally,
always staying in range of home. Others push themselves to the limits of
their ability by flying longer and longer cross-country tasks. Others take
to instructing, either introducing visitors to the sport that we're all
hooked on, or training new pilots from being a complete novice, through to
solo standard, and on to being a cross-country pilot.
Whatever targets you set yourself, you are always facing the challenge of
the weather, and the sense of achievement when everything goes right is
enormous.
What's more, it's unlikely to be anything like what you do by way of
employment, so it's a very good way to relax at the end of a stressful week
at a desk or looking after a family.
Because we're a Members' Club, we all have to work together as a team on
flying days, so there's a lot more to the day than just flying. As a result
of this teamwork, there's a strong social side to the Club, and most people
wind down after a busy day over a drink together in the local pub.
Surely It Is Expensive?
No, not at all. In fact, the overall
Cost of Flying
compares very favourably with many
other hobbies. At Stratford in particular, the costs are very modest, because
we're a Member's Club, and nobody is making a profit out of the flying.
The annual subscription is well below what you would pay for membership for
many other similar hobbies, such as a Golf Club or a Marina. While you're
learning to fly, your flying fees will typically be £20 to £30 a
day, although long flights are more expensive (and very much more enjoyable),
which is many times cheaper than learning to fly a light aircraft.
We run a
Junior Membership
scheme which
gives financial help to youngsters, to the tune of approximately
half the cost of going solo.
We also run a
Junior Sponsorship Scheme
which does a similar thing by providing fixed cost flying.
Most solo pilots want to own their own aircraft, rather than having to
queue up to fly the Club single-seaters.
The most common way to do this is to form, or to join, a syndicate of three
or four people who share a glider. There are many second-hand gliders
available, of various ages, and a first solo aircraft such as a K6
might cost about £4000, shared between four people.
Once you have your own aircraft, you pay launch fees but not flying time
fees, although instead you can expect to pay £200-300 a year
for your share of insurance, maintenance, and certification.
If you try to keep up with technology, though, that's when it starts
to get expensive. All new gliders are built of high-tech materials
and have high-tech cockpits, and for those, you can spend all the money
you have and more besides:
£40,000, £60,000, even £80,000, and that's without
the cockpit computers and satellite navigation systems.
The most expensive glider is the Stemme, a high-performance high-tech
two-seater motor glider, a snip at £120,000.