Gliding
About Gliding
I'm pretty keen on flying, especially gliding! On this page I'll attempt to describe this fantastic sport...
Gliding (or Soaring ), is about flying flying motorless aircraft. Sounds a bit limiting? Hell no! Perhaps I should start by describing a good summer's flight. Read on...
I've been launched to about 2000 feet above the ground by the towplane. It's early afternoon and the day has warmed up nicely. Some hawks are circling in rising air about a kilometre away, I spy them so head off in that direction. Just before reaching them I feel a bump and my instruments indicate rising air. I turn toward the rising wing and start circling below the birds. The lift increases to 300 feet per minute. In a few minutes I'm high enough to move on towards the local hills 10 km away where sit some fluffy thermal cumulus clouds. I push the stick forward, speeding up to 70 knots (130 km/h) and reach the hills in a few minutes.
I'm flying close to the ridge so I can see the if the tussocks moving. They
not: no lift here. I
move on towards a sunny gully a feel a gentle lifting motion and we start
climbing. The gully
runs out after a few hundred metres so I turn back for another run along the
face, always turning away from the slope.
Each beat yields a noticeable gain in altitude and I'm soon at ridge height
where with care I can finally do a complete 360 circle in the strongest part
of the lift. I continue circling, now steeper, at a good 45 deg angle of bank,
shifting the centre to stay in the strongest lift. The thermal lift here is
strong and narrow. I turn tighter, experiencing nearly 2G of force. Luckily I'm
comfy in my seat , because like most gliders the seating position is actually
quite reclined. My vario beeps strongly, indicating the strength of the
thermal. By using my ears I'm free to keep my eyes outside the cockpit and can
keep a good lookout for
mountains and other aircraft. Just then a hawk flicks by, it's using the same
thermal as me and it's very presence confirms I'm in the best
lift.
I fly by feel, always as slow as possible and on
the verge of a stall. Soon we're approaching cloudbase at 7000 feet. The air is
noticeably cooler, in fact at this height it should be about 15 deg C cooler
than
at the airfield.
A flash of sunlight up ahead indicates another glider thermalling over the
higher mountains a few km ahead. I straighten up and head over to join
my colleague. Along
the way I slow up for lift, and speed up in the dead air in between. That way I
reach the range
at the same height I left the the last thermal at...all without further
circling.
In this manner we track along the spine of the range, covering the ground at a good pace. A few old patches of the winter's snow remain in the shady gullies. Already we're 40 km from home and now we drop off the range and into another catchment...I'm now committed to being a long way from home if I can't find more lift and need to land somewhere!
The mountains below are higher now, the tops at 8-9000 feet and the southern
faces are covered in permanent snow and ice. The sunny faces are snow-free and
the black rocks are warmed by the sun. The air is warmed by the rocks and it
rises. We both fly close to the rocks to use the thin layer of lift. At
times we're just a wing span or two from the rocks. Much concentration is
required! If I need to look inside the cockpit I first move out to a safer
position.
The valley narrows and gets very alpine. We're at the Main Divide already, now where to next? North! We cross over the head of another valley, then another. Below us is "tiger country". It would take at least two days to tramp here from the nearest road. The mountains are for climbers only...and glider pilots of course! So long as we stay above the tops we should be high enough to glide out to easier terrain and a landable area if needed.
Now we are a long way from home, and the sun has tracked westwards across the sky. As it gets lower there'll be less heating and fewer thermals. The moist sea breeze is marching up the most of the major eastern valleys. This wind is literally literally "sucked-up" from coast as a result of the many thermals inland. The maritime air is cold, damp, and not good news for soaring. All these factors need considering if we want to get home before "the day dies".
We swing back south, and just in time. Already the sky is changing. Out west the clouds have spread out, forming a layer that blocks the all important sun. To the east I can see signs of the sea breeze: cloud now sits on the tops of the mountains we soared four hours ago. However the run home should be ok if we choose the natural lines of energy along the way. Firstly we stay on the ridge tops, the western faces are still warm and will provide enough lift despite the weaker sun. Then we cross over a wide valley staying well clear of the dead air in it's lower reaches. Pointed peaks on the next range are worth a few turns to gain more height. It's now important not to drop below the tops.
The ridge splits, we each try a different spur and compare progress over the radio. Now personal knowledge and confidence comes into play. I choose to remain on course, aiming for the last real sunny knob up ahead. A good climb here will get me over the saddle and back to home turf. If I land out on the other side at least the retrieve will be easy. My colleague thinks differently. He's confident enough to remain in the valley a little longer and then sneak home via the gorge. We'll see!
I reach the sunny knob after a long smooth glide. I slide over the top and feel a bump. The vario begins to beep happily and I relax again. This may well be the last climb of the day so stick with the climb even as it weakens. Finally at cloudbase I set out at my best gliding speed. I've got plenty of time to select my home airstrip waypoint in the GPS. Hmmm, a 45:1 glide angle is needed. In theory I won't quite make it, as my glider is 38:1. Or at least it was marketed as such over 30 years ago! The miles tick-by on the GPS. With a slight tail wind I gain a small advantage but also know I'll have a southerly headwind for the last few miles. In occasional patches of lift I fly as slowly as possible.
A line of cloud forms parallel to my track. This is possibly the result of two air masses meeting, and if so something must be going up. I deviate a few degrees to investigate. Beep beep beep! Gentle lift saves the day. With increasing confidence I speed up, trying to remain below the lowering cloud. Home is assured now, although the moist sea air and low sun angle makes it hard to see it in the distance. I call the clubhouse on the radio and get the local wind conditions. A strong southerly as expected! With height to burn I can speed up to 120 kts, that's over 220 km/h! I call my intention to practice a competition finish. Just a mile out and the ground flashes by just below. I cross the airfield boundary at low level and carefully pull back on the stick, converting my speed into 500 feet of altitude. Next I do my landing checks, lowering the wheel and turn to land into wind.
And more info from our flying club ...
You can participate in gliding on several different levels, for example many simply enjoy learning to fly, and others want to fly hundreds of kilometres in National competitions. Of course the first step in learning to glide is to have a trial instructional flight with one of our club's qualified instructors. We offer these flights at $100.
Learning to fly
If you decide to continue further then the next stage is leaning to
fly. You will receive both theoretical and practical training from the
club's voluntary instructors.
Practical flying takes the form of launches or tows to medium
altitude and gliding slowly back to the landing strip. You'll be in a 2-
seat glider with the instructor sitting behind you in the rear seat.
Throughout the flights you will be using the controls under guidance
of your instructor. Each flight lasts about 20 minutes but could be
much longer if rising air currents can be found (which is normally
the case). It would take about 20-50 flights before you go solo.
You will also study the following subjects: theory of flight, weather,
air law, human factors and other gliding related matters. None of
the subjects is difficult, especially at this "A/B cert." level.
Post solo flying
After your first solo you will continue learning with advanced
instruction as well as longer solo flights. Increasingly you will be
flying on your own and trying to find rising air or "lift". You are
probably aiming for your "QGP" or qualified glider pilot licence.
Along the way there will be further study towards your radio exam
and other topics such as cross country soaring.
Cross country soaring
Many club pilots reach QGP status and continue to fly within 10 or
20km of their club airstrip. However for others there's the lure of
"heading for the hills" and exploring areas 100km or more from
home. Clearly such flying is out of gliding range of the airstrip and
requires being aloft for many hours. These flights involve using lift:
thermals, wave and ridge lift. You may be flying close to mountains,
or perhaps 20,000 feet above the plains. All the time you will
remain within gliding distance of a safe landing area, this may be a
farmer's paddock or another airstrip. If you land out in a paddock
then (hopefully) fellow club members will drive out to pick you up
and tow the glider home in it's trailer. Modern gliders only take a
few minutes to "rig" or derig and the trailers tow easily behind a
medium sized car.
Awards, competitions (and records!)
There are several internationally recognised award badges that can
be gained. For example flights of 50, 300 and 500km each qualify
for popular awards. Other awards now exist for longer flights that
are now possible in modern high performance gliders. Skilled pilots
have flown over 2000km distance in a day’s flight.
Summer is competition season. Each year there are North and
South Island Regional, plus an annual National competition. Tasks
are set and points are earned for speed and distance flown. Many
pilots compete for fun and friendship, but NZ has produced world-beating
champions too.
Many world records have been set in NZ for speed, distance and
altitude.
Own your own...
If you really enjoy your flying then the time may come to buy your
own glider. The cheapest gliders are now about 40 years old and
can be had for about $10,000. These will be made of wood and
fabric and offer only low to medium performance. These gliders
offer a lot of fun for a minimum investment.
For $20,000-$50,000 you get a fibreglass glider with quite high
performance and requiring little maintenance. These gliders will be
20-35 years old yet still perform almost "as-new". This generation
of gliders currently makes up the bulk of private and club fleets.
They are always popular and hold their value well.
Gliders younger than say 15 years can be quite pricey. This is
because their performance is close to that of a new model, and new
gliders may cost $100,000 or more!
Aside from the initial purchase your next biggest expense will be the
annual insurance bill. This may be 4-5% of the insured value. Other
annual maintenance cost will add another $1000 or so to your
running costs. In general you could say that owning and operating a
medium priced glider will cost about the same as a good sized boat.
Obviously if 2 or more like-minded pilots get together a syndicate
can be formed and this is common practice.
Tp find your nearest club phone 0800GLIDING, or check out the Gliding NZ website.