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How different are glider landings to convention powered aircraft?


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I started learning how to glide. I've done almost 20 flights now in a sailplane, they generally have a nose wheel, a wheel in the middle, and a tailwheel. How different is it for a pilot to land one of these aircraft to say a convention powered aircraft with or without a tailwheel?

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I don't know what  you mean with the wheels, but analyse it. You have a very efficient high aspect wing that won't stop flying without using spoilers and IF you do a min radius turn at slow speed  the inside one may get too slow. You don't have an engine to go around with and if your tug has an engine failure at 50 ft you have a job to do. ALL pilots should do some. Nev

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I agree with Nev. Having been a glider pilot for 40 years before flying power, I have to say that gliders are easier to land than the Jabiru. They have big airbrakes without which landing would be very difficult. With those big airbrakes, landing is easier.

Like any tailwheel plane. they can take off again if flown on too fast. So the technique is to get the wheels a foot off the surface and try to keep it there as it slows down. You land by trying not to.

This is exactly the same as a trike Jabiru. At this time, you are looking well ahead and using small smooth stick movements, gradually feeding in more elevator up as the plane slows.

Its fun learning, and remember that no good pilots take landing for granted. They always try for a "greaser " but rarely achieve a perfect one.

But as Nev says, you can't do a "go around" with a glider!

Edited by Bruce Tuncks
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I also agree with Nev and Bruce. Gliders are conventional aircraft.  As regards landing, I’ve only flown gliders with one wheel and a tail skid, and landing is as per conventional for any tail dragger; fly a conventional circuit, control glide slope with spoiler/brakes or side slip, using the spoiler/brakes/side slip like you would with a throttle, except you can’t do a go around, or like a dead stick landing in a powered aircraft. Cross wind landing is by crabbing not wing down....wing down risks a ground loop from touching a wing tip on the ground.  Most gliders will also pull up fast, say if that fence is coming up too fast, by doing a wheeler landing, applying wheel brakes if you have them and pushing the stick forward to rub the forward under fuselage in front of the wheel on the grass. They also pull up faster if you keep the undercarriage retracted.  
I’ve assumed you understand the difference between nose wheel and tail dragger aircraft in that the centre of mass in a nose wheel aircraft is forward of the main wheels, and so when the mains touch the runway on landing the nose drops and this reduces the AoA on the wings, reducing lift.  On a tail dragger the opposite happens, so if you land with airspeed above stall, the tendency is for the nose to pitch up, increasing the AoA, and you will balloon back into the air.

There are also considerations about how spoilers/brakes affect stalling. The gliding club I belonged to regularly had landing ‘competitions’.  We would put a row of toi toi (pampas grass) across tge runway to simulate a fence.  The winner was the person who went clear over the row of pampas grass and pulled up closest to them.  One time a young bloke came in with the club Blanik, real slow, brakes in, pulled up over the pampas and then snapped the brakes out.  The glider immediately stalled about 1.2m above the ‘runway’ with almost no forward speed, coming to a stop about two plane lengths from the pampas fence.....a hard landing, but easily the shortest. The CFI disqualified him.

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53 minutes ago, Markdun said:

I also agree with Nev and Bruce. Gliders are conventional aircraft.  As regards landing, I’ve only flown gliders with one wheel and a tail skid, and landing is as per conventional for any tail dragger; fly a conventional circuit, control glide slope with spoiler/brakes or side slip, using the spoiler/brakes/side slip like you would with a throttle, except you can’t do a go around, or like a dead stick landing in a powered aircraft. Cross wind landing is by crabbing not wing down....wing down risks a ground loop from touching a wing tip on the ground.  Most gliders will also pull up fast, say if that fence is coming up too fast, by doing a wheeler landing, applying wheel brakes if you have them and pushing the stick forward to rub the forward under fuselage in front of the wheel on the grass. They also pull up faster if you keep the undercarriage retracted.  
I’ve assumed you understand the difference between nose wheel and tail dragger aircraft in that the centre of mass in a nose wheel aircraft is forward of the main wheels, and so when the mains touch the runway on landing the nose drops and this reduces the AoA on the wings, reducing lift.  On a tail dragger the opposite happens, so if you land with airspeed above stall, the tendency is for the nose to pitch up, increasing the AoA, and you will balloon back into the air.

There are also considerations about how spoilers/brakes affect stalling. The gliding club I belonged to regularly had landing ‘competitions’.  We would put a row of toi toi (pampas grass) across tge runway to simulate a fence.  The winner was the person who went clear over the row of pampas grass and pulled up closest to them.  One time a young bloke came in with the club Blanik, real slow, brakes in, pulled up over the pampas and then snapped the brakes out.  The glider immediately stalled about 1.2m above the ‘runway’ with almost no forward speed, coming to a stop about two plane lengths from the pampas fence.....a hard landing, but easily the shortest. The CFI disqualified him.

CFIs have powers to take your licence? I never knew that.

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It's GFA. They may do things differently.

  Another thing with gliders or pushers. If you are going into a fence, ground loop it into wind. then you won't get your throat cut with a fence wire. Nev

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6 hours ago, New2flying said:

I started learning how to glide. I've done almost 20 flights now in a sailplane, they generally have a nose wheel, a wheel in the middle, and a tailwheel. How different is it for a pilot to land one of these aircraft to say a convention powered aircraft with or without a tailwheel?

In powered aircraft the throttle controls your rate of descent and the elevators control your airspeed.  In a glider the airbrakes control the rate of descent, elevators control airspeed. 

Instructors will normally teach students to arrive at base leg in an overshoot situation with airbrakes about half open.  On final the aiming point (not the touchdown point) is kept stationery on a point on the canopy using airbrakes. Airspeed is controlled using the elevators.  Your eyes remain on the aiming point until round out when you then look up to the far end of the strip.  Using peripheral vision you are then able to finely judge the landing and touchdown with the elevator.

In the early days of your training it is best to leave the airbrakes at a constant setting and concentrate completely on the landing. With more experience both the airbrakes and elevator are used almost simultaneously to achieve pinpoint landing precision.

Good luck with your glider training…I have always believed that anyone interested in learning to fly begin with gliding.  Back in the 70s and 80s there was some allowance made for gliding hours (5 hours I think) to be included in the PPL curriculum… a lot of my students, after transitioning to powered flying, would solo in less then 6 hours… many went on to aviation careers.

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Three pointing T/W wouldn't be helped by glider landings. Some U/L's would benefit from having spoilers.. When you go to something "new" ie "different" you can't fly by habit or a 1,2,3 prescriptive technique. You have to leave some aspects of your training behind you and embrace the NEW thing being constantly aware of the differences.. Energy management comes into ALL of it. I fear some wouldn't know what I'm talking about there, but it isn't their fault.. Nev

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Nev, I think you might be over complicating things.

Gliders teach energy management better than powered flying appliances. After all, gliders don't have the luxury of extra energy on tap.

And most gliders ideally land in a three point even though their nose doesn't point as skyward as noisy tail draggers. 

As you point out, proficiency in one machine sure doesn't assure competence in a different machine.

 

I'm no instructor, but I really think that glider experience greatly aids progression to powered flying.

 

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New2 flying. I think you are asking is it good to learn gliding for power. In all aspects including landing the answer is YES! Flying the airframe is flying and leaving the engine out of it to start with teaches the pure concepts. Primacy will be ingrained to fly the airframe which will save your arse if it goes to worms. Spin recovery is taught in gliding as a matter of course and checked annually. If you have the opportunity to learn gliding before you learn power you will never regret it. You will probably glide forever too. Lots of airline pilots are glider pilots.

Sully was a glider pilot and outlander in the Hudson. All good.

Good luck with your learning

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On the Jabiru, I never hear the stall-warning on landing but it sure seems to settle well when the speed has washed off on the hold-off prior to landing.

On the subject of glider-pilots, as well as Sully, there was Neil Armstrong.

 

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And the guy that dead sticked a heavy who run out of fuel in North America...the one where thought he was buying kilograms of fuel but they sold him ‘pounds’.

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Thanks....I also recall that the guy who landed the Boeing convertible soft-top in Hawaii was also a former glider pilot...but not completely sure on that one.  
Anyway, I would advise all people interested in flying to do some gliding; it’s not only good for flying skills & knowledge, it’s also good for your hearing and your soul.  In gliding I learnt about and experienced incipient spins; we spun and had to recover; we did EFATO releases and flew circuits from 200’agl; we always did co-ordinated turns, including close to the ground; we climbed in weak narrow thermals frequently dropping that inboard wing and picking it up with rudder not aileron; we did outlandings which weren’t emergencies; we scared trampers and sheep ridge soaring in the mountains; we flew super smooth wave to 15,000’; we were towed through extremely rough rotor losing and regaining site of the tug in seconds; my kids often got to ride in the back seat of the Cub tow plane; we coastal ridge soared in westerlies below 800’ for ages; we flew with 10 or more gliders in the same thermal; we did aero tows, winch launches, car tow launches, and rubber band launches off the side of a hill with the hang-glider guys....flying for fun at its very best!

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Flew a motor glider called a Motorvalk, it was fun! You flew the approach with airbrake out, the glide performance was so good when you retracted the air rake, it felt exactly like opening a throttle, so pretty much like a powered aircraft in a way. Using the airbrake it was easy it seemed, to judge your ROD to the runway, if you were under shooting, you just “opened the throttle” as such. Of course having the little VW engine up front was a get out of jail card!

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On 16/05/2021 at 4:07 PM, facthunter said:

It's GFA. They may do things differently.

  Another thing with gliders or pushers. If you are going into a fence, ground loop it into wind. then you won't get your throat cut with a fence wire. Nev

My Dad witnessed this happen at Goulburn.  The pilot was highly experienced on a demo tour and failed to get airborne and hit the boundary fence. 

Edited by Roundsounds
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Seriously? .I doubt it had a detrimental effect either.  The Captain should have been in the cockpit as the plane entered the bad weather area as per the forecast. Some of the flight control logic can be cited as being anti intuitive to people who don't fly such equipment. There's no direct connection from control  stick  to the flight controls. Inputs go through microprocessors. I think at the present time a court process is dealing with this matter so I'd tend to discourage any careless or uninformed comment.. Nev

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Didn't say it did and if you bother to look up the accident report you'll see his qualifications.  (edited...mod)

 I'm no fan of Airbus cockpit philosophy nor the modern trend to teach just enough to operate the aircraft under normal circumstances with a some defined emergencies. Little to no in depth understanding of control systems and other systems in the aircraft which may get you out of trouble in other cases.
BTW much the same accident happened again with an A320 off Indonesia some years later.

(edited...mod)
Learning to fly involves knowing effects of controls and practice to get better at it. Time in the air.
Orientation in the air. Time in the air.
Landing. Takes repetitive practice. Difficult and time consuming in a pure glider. Much easier in a powered aircraft (or motor glider).
Takeoff - easier in a powered aircraft. A glider on takeoff/tow is formation flying. Student should not actually handle controls below 1000 feet on tow until satisfactory aircraft control is shown. There have been nasty accidents here.
Learn to fly in a motor glider/ultralight or normal powered aircraft, then it is just a conversion to fly gliders. You'll also know enough to counter some of the bs put about by gliding instructors and other ignorant people in the gliding movement.

The inefficiency of glider training is shown by the GFA's own statistics on membership. Current membership is about half what it was in 1983-84 while the population of the country has increased by more than 50%. Each year about 600 new members join the GFA and about 600+ leave, resulting in a slow decline in numbers. Most who leave do so during or at the end of one year's membership. Sure, some may have got what they want but the vast majority are unhappy about their flying progress and the many unsavoury aspects of the way the GFA and clubs work.

If learning to fly gliders in Australia be aware that the GFA has a very rigid (worse than CASA in many cases) rules based operational structure. There is little to no safety culture. I see GA pilots, commercial pilots, military pilots who discard their professional caution and practices when they get on a gliding airfield. The record of "instructors" (most aren't an instructor's bootlace) killing and injuring students is not good. This is obscured by deliberately exaggerating annual flying hours. Tell me, how does an organisation which has been losing membership (it is compulsory) since 1984 get to fly more and more hours each year?
In the early 2000's, one year they claimed 268,000 hours. There are maybe 700 gliders out of 1100+, which return an annual inspection report which comes to close to 400 hours per year for every operational glider. Doesn't happen. My mates who do annual inspections report 40-60 hours per annum is about average for a private glider. There are exceptions but there are also plenty of gliders which come back with ZERO hours for the next annual. There used to be several full time operational gliding sites. These are now weekend/by arrangement with occasional full time for a month or so a year.

I've got 2700 hours in gliders and self launchers (the retracting engine variety) and 1300 hours GA (most of both flying cross country)and have worked in the gliding industry for 43 years full time designing and manufacturing variometers.
I sure wouldn't let anyone I cared about do ab initio training in gliders in Australia (or NZ - it runs about like Australia).

Edited by robinsm
confrontational and dismissive of comments previously made. Does not advance the subject at all.
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i agree with all of that except my being careless or uninformed about  modern flight control systems. Training is  less than optimum in both situations.  Airbus aim was always to make the plane pilot proof.. Combine that with bad weather and unserviceabilities and you get problems. Automatics can't predict every emergency situation.

 Don't equate the AF  thing with the Boeing MAX philosophy. Apart from the fact they are both commercial jets there's not much carry over between them.. Nev

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