I’ve written before about wanting to be a pilot since I was a small kid but not getting the itch to try gliders until long after getting my pilot license in airplanes. You can read about that here.
I have not seen many accounts of people talking about the differences they noticed and experienced while transitioning to another category of aircraft, i.e., airplane, helicopter, glider, etc. What I want to do below is review the first impressions and notable differences between single-engine airplanes and the glider I first flew in, which was an ASK-21B.
Before I took my first lesson in a glider, the most recent airplane I had flown was a Piper Archer on a short overnight trip in Southern California. I also have my tailwheel endorsement. Most of that time was logged in a 1941 J5 Cub (three-seater). It’s been a while since I have been able to log tailwheel time, but the sensations and memories don’t leave you.
The Glider
The ASK-21B is a product of the Alexander Schleicher Company and is widely used as a modern training platform. A two-seat, tandem arrangement, the cockpit is snug and the seats reclined in a way that allows for a sleeker design for a more efficient flight profile. A bubble canopy provides for near 360-degree visibility for both pilots. This comes in handy when entering a thermal with other gliders.
The airframe has five wheels; two small “rollerblade-style” wheels on the wingtips, a tail wheel, main, and nose wheel. Compared to a Cub or Archer, the wingspan is quite long (55 feet, 9 inches vs 30 feet for the Archer). The wings-level stance of the glider is low to the ground; something akin to being in a sports car. At rest and unoccupied, the airframe sits slightly nose-high on the lateral axis, the weight being distributed between the tail wheel and main wheel. Once you sit inside the cockpit, the weight shifts to the main and nose wheel.
The glider is not equipped with flaps but does have spoilers which deploy on the top of the wing to slow the aircraft down and increase the rate of descent. Different gliders have different types of drag inducing devices. Because there is no engine, there is also no alternator to run electronics. A battery is installed to handle the power for the radio and navigation. There are no navigation lights or anti-collision beacon, although there are companies that offer the equipment.
The ASK-21B has a variometer which is something like a vertical speed indicator but equipped with an audible tone that indicates rising or sinking air. There is no turn and slip indicator. Instead, a small piece of red yarn is taped to the outside of the cockpit in the view of the pilot. When flying coordinated, the “yaw string,” as it’s called, remains straight. If the glider is skidding or slipping, the top of the string will move to side of the turn requiring less rudder input from the pilot. This can be slightly confusing to some pilots who are used to “stepping on the ball.”
In his book, Transition to Gliders, famed glider pilot and author, Thomas Knauff advises pilots to step on the sticker (it’s a circle, much like a ball). This way of thinking about it, made it easier for me; I was instinctively stepping on the moving part, which in this case, was the top of the string. That was not helping to keep us coordinated. One note about flying uncoordinated, the sound gets much louder as more of the airframe is exposed to onrushing air. This is probably similar to powered aircraft but it must be drowned out by the engine noise and/or the pilot headset.
The Obvious
I’ve never flown an aircraft with five wheels before. Nor had I operated anything so low to the ground or with a one-wing-down starting stance. That was all definitely new to me. Also, the really obvious difference was the lack of an engine. I’ve written about the many ways to launch a glider. You can read about that here.
Where I was flying, we used the aero tow method with a Piper Pawnee as the tow plane. After pulling the glider out of the hangar and completing the preflight walkaround inspection, we hooked the tow rope to the hook under the glider, about two feet back from the nose and slightly forward of the nose wheel. Note: each glider design is different so the tow hook location may vary depending on what is being flown.
Since a glider has no engine, the pilot must always be calculating altitude as potential energy in a calculation based on the aircraft’s glide ratio. For the ASK-21, the ratio is 34 feet forward for every foot of altitude lost. For my initial flights, we added a buffer and worked with a loss of approximately 200 feet for every 1000 feet traveled. Put another way, 1000 feet of altitude gets you five nautical miles (30,000 feet) of distance over the ground (dependent on weather conditions, weight of the glider, airspeed being flown).
Being on Tow
Being on tow was a completely new experience for a variety of reasons: sharing the active runway with another aircraft; taking off in close proximity to another aircraft; and following the tow plane efficiently are a few of them. As mentioned above, the tow plane was a Pawnee, which is plenty capable of pulling a glider. In fact, it’s not uncommon for a Pawnee to pull two gliders at once. We didn’t use a wing-runner (someone to hold the wings-level before launch), so the first stick input was full opposite aileron until the airspeed was sufficient to lift the low wing. Once the takeoff roll began, it was literally just a few short seconds before the glider floated up into ground effect. The tow lifted off a few hundred feet further down the runway.
Things happened fast and there were many things requiring my attention. Since this was a new airframe for me, the control sensitivity, trim, roll rate and pitch rate were all things I was working through while trying to keep my position behind the tow. Later in my training the CFIG and I would begin to focus more on briefing abort points and rope break decision altitudes. We made a gentle climbing left turn over some power lines and then continued a standard climb rate of somewhere between 500 and 1000 feet per minute at an airspeed around 60 knots.
The Not so Obvious
After releasing from tow and beginning to get the feel of the glider, we began to explore the flight characteristics of the aircraft. My first instinct was to pitch for best glide (VBG). In fact, I recall my instructor telling me to pitch for minimum sink (VMS) and I immediately thought that was just a different way of saying best glide. Perhaps, I should have re-read the Glider Flying Handbook, but the confusion was easily cleared up while we were still in the air.
Upon further study, I figured out that minimum sink signifies the greatest amount of time in the air and best glide is for greatest distance achieved. This is something like the relationship between VX (best angle of climb) and VY (best rate of climb). Perhaps I shouldn’t confess that lack of part of the story, but maybe it’ll be helpful for you before taking your first glider flight.
Landing
On approach back to the field, the instructor and I briefed the established procedure for reaching the initial point (IP) near the landing area and starting the entry to the pattern. At the field we were operating out of, you plan to arrive at the IP at 1200 feet and enter the downwind at 1000 feet, much like in powered planes. Around this time, I was reminded there are no go-arounds in a glider.
We orbited the IP (named “Two Barns”) looking for traffic, listening to the radio, running a landing checklist, and observing the traffic pattern and runway environment. This is very similar to being in a powered plane except for the fact that you must begin your approach before all your altitude is gone.
One of the items on the before landing checklist is “check spoilers.” As I mentioned before, spoilers were new to me. The procedure was to unlock and cycle the spoilers to full, then return them to closed, but not locked, for the rest of the landing sequence. It was drilled into me that it is important to visually check the movement of the spoilers by looking over either shoulder. There is a characteristic clunking as the spoiler handle unlocks. You also experience a sinking feeling as lift is interrupted.
Flying the rest of the pattern was quite similar to what I was used to. We constantly checked and fine-tuned our distance from the runway; mindful of wind drift and ground speed. When we made our turns in the pattern, the bubble canopy gave beautiful views of the landing area – no major blind spots to speak of on the low-wing side.
We pitched for 55 knots on the airspeed. Since there is no throttle, the spoilers act in a similar fashion to help adjust the position (high/low) on the approach path. The instructor advised to move the spoilers to either, closed, half, or full; wait three seconds to evaluate the flight path, then decide on the next course of action with any necessary spoiler changes. This was very helpful in preventing me from ‘chasing’ the perfect descent angle.
When we were finally over the threshold and entering the flare, the proximity to the ground was much different than any previous aircraft I had flown in. Like I mentioned above, it’s like the difference between driving a moving van and driving a sports car; the impression of speed is greater, the closer your eyes are to the ground.
The pitch attitude at touchdown was like a three-point landing in the Cub; let the airspeed bleed off while keeping the nose and main wheel just a foot or so above the runway. When the time is right, the tail and main tires touched down and then the weight shifted from tail to nose wheel as the glider decelerated and brakes were applied.
That’s one more little detail to mention. There are no brakes on the rudder pedals of the glider. In the ASK-21, the brake is applied by pulling the spoiler handle open. Ground steering is accomplished with the rudder while sufficient airspeed still allows for control effectiveness.
How it Felt
So many people describe the serenity of being in a glider, just soaring about with no noise of an engine. While I did notice the obvious lack of engine noise, the real sensation of peace was experienced on the way back to the gliderport. We were cruising at 3,000 feet in calm air with an indicated airspeed of 55 knots when I suddenly realized just how peaceful it all was; quieter than driving in a luxury car down the freeway. At least, that’s the impression I remember. I even mentioned to the instructor how easy it was to let go of the controls, sit back, and let the glider maintain level flight.
From a sentimental point of view, glider flying made me feel like I was traveling back in time, notwithstanding the “modern design” of the glider I was in. Glider flight is how it all started, way before the Wright Brothers or Santos Dumont ever figured out powered flight. When we landed the glider after my first flight, I had a perma-grin from the excitement and newness of it all. Flying gliders was something I never thought about doing until I was already a power pilot but I’m so glad I finally did.
Would I Recommend it?
Absolutely, yes. I would recommend flying gliders to everyone, including my younger self. I have talked to countless pilots who are rated in other categories of aircraft and have flown gliders. They all agree that having at least taken a few lessons (even if you don’t complete your add-on rating) is a great way to improve many aspects of your flying skills.
It’s challenging, freeing, cheaper, and offers so many benefits. I would rate both tailwheel and glider flying high on the “mandatory” list of things every pilot should learn. I wrote about the Seven Reasons You Should Fly Gliders here.
If you do a little bit of research about glider flying, you may soon find that many of the very best aviators in aviation history have flown them. Names like Lindbergh, Armstrong, and Sullenberger represent a very small preview of the stories you’ll find.
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