61
votes
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Has any airliner ever collided with a glider?
Yes. (I found this by Aaron Holmes's hint that he searched only English sources.)
On 1999 Feb 12 at 3:40 pm, a Grob G103 sailplane F-CGXB (possibly "in wave flight") collided with an Airbus ...
- 10.5k
40
votes
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Why can gliders fly for so long?
A glider and a paper airplane operate on the same principle: Exchanging whatever potential energy (altitude) they have for the kinetic energy (airspeed) required to keep air moving over the wings so ...
- 68.2k
40
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Why are birdlike airfoils not used?
Early biplanes did use similar airfoils. Not as extreme as the Eppler 376, but still very thin and highly cambered.
When Otto Lilienthal started his glider experiments, he tried to copy storks. He ...
- 228k
33
votes
Can you fly a glider in a cloud on primary instruments?
With basic instruments (altimeter, speed and climb indicator and compass): Forget it!
A glider can enter a cloud when thermalling into it from below. Below the cloud the rising air was governed by ...
- 228k
33
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Is it normal for gliders not to have attitude indicators?
Yes, it is normal. With very rare exceptions, gliders are not allowed to operate in IMC (instrument Meteorological Conditions) and must remain clear of clouds. There are also powered aircraft that do ...
- 12.5k
32
votes
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Would building a large asphalt square or painted dark black area create a "thermal generator" for glider use?
Yes, if it was large enough you could expect decent thermals from it, but not all the time. I've flown over mall parking lots where there is maybe 20 acres of asphalt, expecting a boomer, but no joy. ...
- 125k
31
votes
Why are the wingtips of sailplanes painted red?
White is indeed chosen for thermal reasons. Gliders use epoxy resins which cure at room temperature and are then tempered at 60°C. This tempering shifts the glass transition temperature to something ...
- 228k
31
votes
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Will dual-learning in a glider make my airplane learning safer?
Yes learn both, but... not at the same time. As Dave says, there are too many differences to be absorbing simultaneously. It's like a new airline pilot taking a type course on a Dash 8 and an RJ at ...
- 125k
31
votes
Can you ride a storm to save fuel?
Not storms, but there is a concept called "Pressure Pattern Flying" where you plan routing to stay in favourable circulation around Highs and Lows, to the extent that deviations to follow ...
- 125k
31
votes
Accepted
What is the lift to drag ratio of a human being?
I'm an ex skydiver. It's a position known in skydiving as a "Flat Track", and is more or less the same configuration as a ski jumper takes. Legs together (ideally), bent forward at the hips ...
- 125k
30
votes
Accepted
Are there any gliders that can fly over the Himalayas?
Do gliders (sailplanes) use ridge and wave lift in the Himalayas to go to extreme altitudes, possibly above Everest's peak?
Yes, there are gliders touring Himalayan peaks over 8,000m, including ...
- 69.8k
27
votes
Accepted
When flying a glider in emergency situation, would it be more safe to bailout or to land in a forest?
Thankfully, I never had to make this choice. In my training I learned to stay in the plane and flare at the height of the treetops, then let the plane sink into the branches and have them stop and ...
- 228k
27
votes
Why are winches not used for towing commercial planes up?
If you ever get the chance, do try a winch start in a glider. It is, to say the least, an interesting experience. I do not believe it would be accepted by the general public.
So, that is one more ...
- 1,526
27
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Why aren't any wingsuits able to sustain flight?
I'm aware that under zero power it is a glider, but there are gliders
that sustain flight and have enough lift to climb etc.
This statement is a bit incorrect. Gliders don't climb like aircraft as ...
- 100k
27
votes
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Plane that always flies into the wind?
The short answer is no.
All the glider feels is its flight relative to the air. What the ground is doing beneath it is not relevant, the wind could be blowing a hundred kilometers an hour and the ...
- 6,932
26
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Why are winches not used for towing commercial planes up?
I won't prove it's not possible, but I'd would be surprised it is. I'll develop the reasons why and provide the physical framework you can use to compute a solution to have, with some effort, a final ...
- 69.8k
26
votes
Are gliders susceptible to bird strikes?
Gliders, as every other aircraft, are susceptible to bird strikes. This is a detached glider's tail after hitting a 10 kg vulture:
The accident was caused when the crew lost control of ...
- 4,282
26
votes
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Are glider winch launches rarer in the USA than in the rest of the world? Why?
To expand on Quiet Flyer's answer, it's technical and economic at the same time.
Technical: Winch is limiting because you are deposited in the same spot over the field, whereas a tow, if the pilot ...
- 125k
26
votes
Why are 3- or 4-seat gliders so rare?
Because much of the fun in being in a sailplane, is in actually flying the sailplane. It's not a means to get from point A to point B, it's a means to enjoy the magic of flight, much of which ...
- 21.4k
25
votes
Accepted
Is it safe to fly a glider when I can't move the stick fully left and right?
Yes, it is safe.
Well, there is a reason why the stick travels as far as it does. One is the restriction in long-term maximum stick forces of 15 N (see §22.143(b) in the linked PDF), which is easier ...
- 228k
24
votes
Accepted
What is the most 'environmentally friendly' way to learn to fly?
Here are some options for flying in an environmentally friendly way:
Use an electric trainer: Since last year the all electric trainer aircraft Pipistrel Alpha Electro has FAA certification. Assuming ...
- 53.6k
24
votes
Accepted
Why do the ailerons of this flying wing work oppositely compared to those of an airplane?
Most likely the adverse yaw effect (due to the induced drag of the increased lift on the down-aileron side) is causing the wing to yaw the opposite direction from the intended roll, and the yaw causes ...
- 16.8k
23
votes
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Should head stay level or inclined in a bank?
I am not a glider pilot, but the principle holds for flying any fixed wing aircraft1: you should keep your head level with the aircraft, as you described, not the horizon.
As your instructor ...
- 16.5k
22
votes
Is it feasible to circumnavigate the Earth in a sailplane?
No. Both night and oceans would be major obstacles.
Night time can be survived by parking the glider in ridge lift but it requires a steady wind during the night. This is possible and has been ...
- 228k
21
votes
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Why do sailplanes have such large tails?
Keep in mind that not all sailplanes are designed for extremely light weight. Decreasing the weight also decreases the minimum sink rate, but doesn't help the still-air glide ratio, and actually ...
- 21.4k
21
votes
Accepted
Can gliders and single-engine planes have vortices?
The vortices that you are referring to (I think) are wing-tip vortices, a product of the wing generating lift. Since glider wings do generate lift (due to the airflow over the wing) and are propelled ...
- 32.4k
20
votes
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Do thermals stop rising when clouds are formed?
No, the opposite is in fact true. When the water condenses, it releases latent thermal energy, causing the air to rise even faster. That is why some glider pilots (who are appropriately licensed) fly, ...
- 35.7k
20
votes
Is it normal for gliders not to have attitude indicators?
As pointed out by Juan's answer, they are not required for the kind of operations allowed for gliders, so they are left out for cost reasons.
Furthermore, artificial horizons are relatively complex ...
- 8,531
19
votes
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How can the Perlan II glider climb to 90,000 feet?
Perlan II will climb to extreme altitudes on wave lift, not thermal lift. Wave lift is created when strong winds blow approximately perpendicular to a mountain range, and the wind speed increases ...
- 931
19
votes
Accepted
Why aren't any wingsuits able to sustain flight?
There are very small jets that for hype-related reasons are called wingsuits. As current jet technology (and propeller technology) is easily capable of producing (from a human-portable frame) enough ...
- 438
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