Questions tagged [glider]

A glider is a heavier-than-air aircraft that is designed to be operated in unpowered flight.

Filter by
Sorted by
Tagged with
0
votes
0answers
63 views

Does altitude affect glide ratio?

Lower altitude means higher air density, which means more liff, which means a glider can maintain a given glide slope at lower airspeed. As a rule, aircraft tend to have higher peak L/Ds at low ...
1
vote
1answer
84 views

Could the Perlan II glider be used for nearspace tourism?

I asked the same question about the SR-71 Blackbird, and I'm also curious about the Perlan II sailplane which travelled above 70,000 ft, and is planned to be flown to 90,000 ft, if it could be used ...
12
votes
2answers
3k views

Is it feasible to circumnavigate the Earth in a sailplane?

Would it be feasible and survivable to circumnavigate the Earth in a glider or sailplane without propulsion and without landing until the circumnavigation is completed, when you'd return to the same ...
9
votes
2answers
3k views

Why do the ailerons of this flying wing work oppositely compared to those of an airplane?

I made this simple wing glider and put some ailerons on it. I thought that the ailerons in this glider would work the same way it works on airplanes, wherein the roll will be in the direction of the ...
9
votes
2answers
3k views

Why do sailplanes have such large tails?

Since a sailplane is focused on performance - what with tricky laminar flow airfoils and all. Eo why this Instead of this It looks to me like that long tail is needed to balance the cockpit. Buy ...
0
votes
0answers
67 views

What examples are there of top-mounted engine motor gliders?

I would like to know which motor gliders are there with regards to the following criteria: Top-mounted engine stowable landing gear great L/D ratio high maximum g-load at least 180kg usable weight? ...
0
votes
1answer
70 views

Is there any formula that directly relate density to altitude for a wide range of altitude?

I am working on a code to simulate a vehicle trajectory based on forces act on it in different altitudes, I need a formula that gives density in an altitude range between 0 and 40 km to obtain lift ...
0
votes
1answer
72 views

In what airspace may gliders fly in clouds in the UK without an IFR flight plan and without contacting any air traffic control facility?

In what airspace may gliders (sailplanes) legally be flown in clouds in the UK without an IFR flight plan and without contacting any air traffic control facility? Also, how high does this class (...
0
votes
1answer
142 views

Is it fairly common for student glider pilots to have wing tip strikes, especially in gusty cross wind conditions?

Is it fairly common for student glider pilots to have wing tip strikes, especially in gusty cross wind conditions? I understand gliders are landed level, slow down and then the wing drops onto a wing ...
1
vote
1answer
129 views

Does a RC glider always loop when launched?

In the below video, the guy sets "launch mode" for hand launch where he adds a little bit of elevator. Will a glider always loop up when launched horizontally, even if the tail is set to ...
3
votes
1answer
106 views

What are “secondary precessional forces” that apply to boomerangs in flight?

note: This question is about the aerodynamics of boomerang flight and how it differs in microgravity environments. Some background information available here in Aviation SE: Are frisbees and ...
2
votes
6answers
466 views

Why can't you have sail-powered airplanes?

So, sailing boats take the kinetic energy of a crosswind and turn it into thrust by using their sails as lifting surfaces, and the discussion I had in the comment section of this question made me ...
1
vote
2answers
237 views

Can we show through simple geometry rather than formulae or graphs that the best glide ratio occurs at the maximum ratio of Lift to Drag?

For an unpowered glider, can we show through simple geometry involving force vector diagrams, rather than mathematical formulae or graphs, that the best still-air glide ratio is achieved at the angle-...
13
votes
2answers
5k views

Why are birdlike airfoils not used?

Here are two airfoils (lets focus on Re 100,000): SD7043-il which is simple to build and has a glide ratio of about 60 e376-il a birdlike and much harder to build if using paper or similar due to the ...
4
votes
1answer
430 views

Can the load factor during glider winch launch be measured with the G-meter?

I am looking at the flight envelope of a glider, the velocity - load factor diagram. I read that generally the air-frame, the G-meter and the pilot 'experience' the load factor as a G force (an ...
25
votes
2answers
5k views

Has any airliner ever collided with a glider?

I've read about many near-collisions between gliders and airliners, but did such a collision ever happen in mid-air, actually?
2
votes
3answers
216 views

Could gliders be a clean, practical alternative to other forms of transport?

Would it be possible to use pure gliders as an eco-friendly mode of transport? From what I have read so far, gliders can travel at a speed of 100-170 km/h. That would not be able to compete with a jet ...
3
votes
1answer
146 views

How much altitude can a glider gain only from losing speed?

Say we have a glider flying near its top speed. If pilot decides to "trade speed for altitude" how much can it climb before hitting stall speed? Assuming pilot will use most effective climb ...
10
votes
2answers
4k views

Can you ride a storm to save fuel?

Cargo sailboats, of the old, depended on wind direction. Like these ships, planes also save time by flying with the wind. On the extreme end, could a plane use storm fronts or hurricanes by flying in ...
1
vote
2answers
149 views

In a full-rudder sideslip in a Schweizer 2-22 or 2-33 glider, is the descent rate higher at 50 mph airspeed than at 60 mph airspeed?

Is it really true that in a full-rudder sideslip in a Schweizer 2-22 or 2-33 glider, the descent rate is higher at 50 mph airspeed than at 60 mph airspeed? Likewise, is it really true that in a full-...
8
votes
7answers
4k views

Plane that always flies into the wind?

Suppose that you dropped an uncontrolled, dummy glider into the air. You want it to always face into the wind by design. Would it be possible? If so, what would such a plane look like?
2
votes
1answer
257 views

Does a glider pilot need to file an IFR flight plan to legally fly in cloud in class E airspace in the US?

Does a glider pilot need to file an IFR flight plan to legally fly in cloud in class E (controlled) airspace in the US? Or could he or she contact ATC and receive a clearance to enter cloud without ...
2
votes
2answers
161 views

What can be approach of balancing canard glider model?

There are a lot of instructions out there about balancing classic wing configuration glider models. The center of gravity should be approximately 25% to 30% from the front edge of the wing, which is ...
2
votes
1answer
173 views

Relationship between wing aspect ratio and speed [duplicate]

For some reason, I cannot find a relatively straightforward source online which discusses the relationship of wing aspect ratio and how it affects speeds of an aircraft. Specifically, is there a ...
4
votes
1answer
273 views

How can a designer maximize the glide ratio of an aircraft with low aspect ratio wings, other than by increasing the aspect ratio?

As I understand it, the gliding range is given by a lift to drag ratio—hence to increase the gliding range, I would want to increase the lift and reduce the drag as much as possible. To that end, ...
2
votes
1answer
59 views

What is the threshold between high Aspect Ratios and low Aspect Ratios?

Oftentimes when describing flying organisms and vehicles, their wings are said to have a "high aspect ratio" or a "low aspect ratio". Sometimes the papers (that I read) gave the numbers, but more ...
3
votes
1answer
366 views

What are the advantages/disadvantages of a forward-folding propeller?

The AMS Carat A is a motorglider with a forward folding propeller. To my knowledge, this is the only production plane with this characteristic. The most popular self-launching gliders with front ...
6
votes
1answer
869 views

How big is the radar cross section of a modern glider?

I heard somewhere that modern glider made of plastic and composite materials are less detectable than other aircraft by primary radar. I wonder how much. What is the radar cross section of a typical ...
4
votes
2answers
157 views

Do pilots ever intentionally land a monowheel glider on the main wheel and a wingtip wheel in crosswind conditions?

Do pilots ever intentionally strike a wingtip when landing a mono wheel glider in gusty crosswind conditions? I understand the Lazair changed from a mono wheel to a standard tail dragger layout for ...
0
votes
4answers
274 views

When do the lift and drag vectors contribute a force component along a glider's path of travel as seen from the ground?

It is often said that the lift vector helps to propel a glider forwards. The lift vector has no component acting parallel to the glider's trajectory through the airmass, but in many cases the lift ...
5
votes
7answers
1k views

An airplane has an engine that pushes its flight. What force pushes a glider to fly? [duplicate]

An airplane has an engine that pushes its flight. What force pushes a glider to fly? Is it gravity? I think the flight of a glider is driven by gravity, but some people disagree with me. They say ...
5
votes
1answer
234 views

Do gliders make a better pilot? [closed]

I've often heard that learning to fly gliders makes you a better airplane pilot, in person and in answers here and here. Is this true, and if so, what specifically is it about gliders—or at least ...
1
vote
0answers
60 views

Why does increasing a glider's weight using water ballast improve its speed and performance? [duplicate]

I was studying gliders and how they fly. There is a point that's not clear to me: why does using water ballast improve the performance/speed of a glider? If I understand correctly, my glider jumps ...
0
votes
1answer
83 views

Does the FAA construe FAR 91.225 to prohibit aircraft w/o electrical systems w/o ADS-B-out from flying above 10,000' MSL unless below 2500' AGL?

Does the FAA construe FAR 91.225 as imposing a general prohibition on flight above 10,000' MSL (excluding airspace below 2500' AGL) in aircraft without ADS-B-out, even for aircraft without engine-...
2
votes
2answers
96 views

Is it harder to get a first pilot certificate in a motorglider compared to a normal powered aircraft (near St. Paul, MN.)?

Is it harder to get a first pilot certificate in a motorglider (glider - self launch) vs. normal powered aircraft near St. Paul, MN. It seems like a self launch glider certificate would be a great ...
1
vote
1answer
138 views

How do I choose the correct params?

I am very new to airplane design. I am working on this project to design a flying wing glider (no propeller) that would glide in a circular pattern with a fixed radius of 250 m after being released at ...
1
vote
1answer
69 views

What parameters to focus on when constructing a wing for turning? [closed]

I want to construct a flying wing (glider) with the sole purpose of performing a helical turn (or a circular turn with no propulsion attached) with somewhat of a fixed radius. What should be the main ...
-1
votes
1answer
147 views

How to decide the wing span? [closed]

How would you decide the wing span for a delta wing glider? Also how would it relate to the main chord length?
0
votes
3answers
190 views

How to glide in a circular pattern?

I was just curious as to how you would make a glider glide in a circular pattern ( or helical ). Will there be a large difference when considering a conventional glider vs a delta wing glider?
1
vote
0answers
46 views

If a glider had human pedal powered propellers how much extra distance could you go? [duplicate]

Imagine an amateur cyclist could generate 100 watts of power (professional ones can do 200-300), would it be possible to put that to use in a glider to fly further? For example you pedal for 15 ...
1
vote
1answer
743 views

What is the differance between gliding for maximum range and gliding for maximum endurance? [duplicate]

Is there a difference between gliding for maximum range vs. endurance? Is the glide speed the same for max. endurance and max. range?
8
votes
5answers
4k views

Why are the wings of some modern gliders tadpole shaped?

Why are the wings of some modern gliders tadpole shaped, rather than teardrop shaped? An example is the Schleicher ASG 29. Or did they just add a flat plate at the trailing edge for the flaps and ...
2
votes
1answer
2k views

How to calculate or design glide ratio? [duplicate]

Was interesting to watch the explanation about glider here, especially about the glide ratio. Glide ratio is defined as the ratio between altitude when it start gliding (Y-axis) to the distance it can ...
2
votes
1answer
320 views

How does the glide ratio change with velocity in a glider with air brakes deployed?

I'm interested in how the glide ratio steepens when increasing velocity, starting from the best slope (best L/D) velocity, in a high drag configuration (air brakes fully extended on a glider). I've ...
3
votes
1answer
255 views

Does lift coefficient for maximum range change for a glider experiencing headwind?

When a glider or unpropelled aircraft experiences headwind, I understand that the flight velocity and sink velocity for the "new" maximum possible range both increase (see velocity polar from How does ...
10
votes
2answers
1k views

Why do gliders have bungee cords in the control systems and what do they do? Are they on all control surfaces? What about ultralights?

Why do gliders have bungee cords in the control systems and what do they do? Are they on all control surfaces? Why don't ultralights have them?
6
votes
2answers
679 views

How should a glider pilot handle inadvertently entering a foreign country?

Typically, when an aircraft lands on a different country than its departure, it has to land on an international airport. There many services are provided like customs, passport control etc, to make ...
12
votes
10answers
5k views

What is the most 'environmentally friendly' way to learn to fly?

As this question indicates, I've been thinking recently about the environmental impact of flying (since when automated cars are the only means of ground transport, aviation will be responsible for ...
5
votes
1answer
213 views

Would all these three things have the exact same effect on the flight duration of a glider?

Consider a glider trimmed to fly at some given angle-of-attack, gliding in smooth air (no thermal convection, ridge lift, wave lift, etc.). If air density is somehow kept exactly constant in all ...
15
votes
4answers
4k views

Are glider winch launches rarer in the USA than in the rest of the world? Why?

I had heard before that winch-launching gliders was a relatively rare practice in the USA, while quite common in the rest of the world. My data is mostly anecdotal, but I do know gliding clubs in ...