Pilots are remarkable folks in many ways, some of them quite entertaining. For example, my informal research has shown that over 90% of pilots consider themselves well above average when it comes to airplane handling skills. This is certainly a possibility, but it requires that the remaining 10% or so be so deficient that I believe the FAA and perhaps even passersby would take notice. Perhaps because I learned to fly with my little brother, who really is somewhat above average, I never had the illusion that I was a particularly good pilot…enthusiastic? Absolutely! Highly skilled? Well, he has not screwed up too badly yet, but neither has he accumulated too many hours. And many of those were supervised. And there was that runway excursion we could mention. And the time he tried to leave with the chocks firmly in place. Actually – ‘times’. No, I have never thought of myself as the reincarnation of Wolfgang Langewiesche…but I did think I had passable stick and rudder coordination.
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| This is how the plane looks at rest, I did not just miss the runway. |
Then I tried gliding. My wife and I had a daughter, and I arranged to take a month in Hawaii to get some field work done and get to know the new baby. I quickly discovered that airplane rentals in Hawaii were beyond my means and somewhat impractical, but there is a healthy glider gang that operates out of Dillingham Field on the northwest corner of Oahu. That seemed like the ideal next step in my flight training. I headed up to the airport to find two operations that would train new glider pilots. There was nothing to choose between them as far as I could see so I walked up to the one that appeared to have a person right there, right now for me to talk to. After some negociation we settled that I would take my glider ticket with the chief pilot/instructor/sightseeing flight pilot. I was asked when I would like to start and answered as any completely addicted flyboy would – immediately.
Well, there was about two hours of ground school and then we climbed into the two seater Grob 103. I have no other gliding experience so I can’t say how this plane compares to the others, but as an SEL pilot I will note a few differences that I found striking. First of all the wings are exceptionally long and have a narrow chord. This is an efficiency issue and does an impressive job cutting down drag. The landing gear is just two wheels, and these are placed one in front of the other. At rest the Grob lies with one wingtip in the red dirt. Upon climbing in to this, my first tandem two seater, I was struck by the lack of instruments. There is an altimeter and a very sensitive vertical speed indicator but no radio, intercom, transponder, or GPS. This is rudimentary, seat of the pants flying.
We were towed into the air by a conventional airplane which spends the day hauling the motor-deprived into the blue yonder. The sailplane, once airborne, will get lift from two principle sources. The first is the ridge of land that lies at an oblique angle to the nearly constant trade winds. The wind hits the ridge and rises to flow over it. A canny glider driver can ride the face of the ridge indefinitely, catching the rising air close to the ridge and then falling out and away before returning to the ridge for another updraft. The other source of potential energy is the rising air at the center of the minor convective activity that is an afternoon feature in Hawaii. Heading for the dark underbelly of a cloud will quickly land the glider in a rising column of air feeding the nascent thunderhead water and heat.
This first familiarization flight allows me to try my hand at both types of lift. Apparently I do passably well as we are still up in the air some 25 minutes into the experience. However, something about my flying seems to trouble my instructor, and he asks me to head out towards the sea and roll the plane back and forth. Specifically he asks for ‘Dutch Rolls’. Now it is entirely possible that this is a maneuver that is required for the private pilot license, and if so I would direct your recollection to the fact that these writings are complete fictions. But, if it excusable that I had never tried this then I will admit that my first thought was that this was an odd culinary tradition of the glider set. I kept on a straight and level heading expecting some cheesy baked good in return for my ridge lift and thermal lift performance. Instead I was treated to a demo of the Dutch roll. It is simplicity itself to explain: waggle the wings so that the nose of the plane sits on a point and the fuselage rotates some 45 degrees about its long axis. Having since tried this in every airplane type I have flown I can say with certainty that the Grob 103 is the hardest plane in which to execute this simple maneuver that I have flown.
A car driving through town on the way to the airfield is controlled along one axis – yaw. Turning the wheel causes the car to move about an axis that runs from the top to the bottom of the car. Once you get to the airport and get in your plane there are an additional two axes to deal with. The yaw axis has been moved from your hands to your feet, explaining the sometimes panic stricken look on student pilots as they miss the turnoff because they are turning the control yoke rather than mashing the foot pedals. Rotation about the long axis of the plane, called ‘roll’, is controlled by turning the yoke. The nose up/down movement, rotation about an axis passing from one side of the cabin to the other is called pitch and is controlled by pushing and pulling the yoke. Or, in the case of the glider, a stick that serves the same function as a yoke. In an ideal airplane these three axes could be controlled completely independently: a control input that changes the roll axis would have no effect on the other axes. Of course the real world is not so neat.
Roll is controlled by a pair of ailerons, one on the trailing edge of each wing. When rolling to the right the right side aileron goes up and the left side goes down. This pushes the right wing down and the left wing up. It also changes the amount of drag on each wing and it is the downward moving wing that has less drag. Since there is less drag on the downward wing side a yaw is induced towards the left. Get it? A roll right leads to the whole plane yawing left. This is called adverse yaw because it is acting in the opposite direction from the roll. After a fairly short time most pilots figure out that adverse yaw is easily corrected with a little bit of rudder; since you are countering a left yaw a little right rudder will do the trick. Sounds easy and really, in most airplanes I have flown it is easy. For one thing, the tail of the plane is big and far away from the cabin, so there is a lot of stability in the yaw axis. For another the ailerons can be designed to minimize the drag changes when they are moved. However, gliders have very long, narrow wings and the ailerons are also long. This leads to an impressive amount of adverse yaw.
A skilled pilot would have figured this out while boxing the wake the very first time they were towed into the air. Me? I had no idea that I was not coordinated in my turns, that is, I was completely ignorant of the fact that my roll was causing the nose of the plane to push out the wrong way. I attribute this to the newness of the sensations and the complete lack of the simple slip indicator I was used to from powered flight. This is nothing more than a black ball in a tube that has a slight bend in it. The bottom of this gentle curve is towards the floor of the plane, and the little black ball sits happily at this lowest point as long as gravity points in that direction. When you turn the plane in a coordinated fashion, making sure there is no adverse yaw, the ball stays planted firmly in the middle. It is possible to spin the plane through 360 degrees around its long axis without ever causing the ball to move from the center. If you don’t believe me, take a look at Bob Hoover’s tea trick. If the plane starts skidding or plowing through a turn that ball will move from the center in the direction of the gravity vector. Stepping on the rudder pedal on the side that the ball has moved to will return it to the center. But, no ball, no idea what I was doing in a turn. That was when the instructor pointed out the yarn.
Yep, this lightweight plane, with darn near no instrumentation, had a 4 inch piece of brown yarn scotch taped to the bubble canopy right in front of my eyes. As I turned left and right the yarn was flopping first to one side, then the other. The wind around the canopy was telling me when I was uncoordinated and the yarn was revealing the wind’s movement. Yarn does not work on propeller planes because the prop wash over the windshield ensures that regardless of how ham-footed you are the yarn will always call you Georges Guynemer. Turns out I was not just bad at Dutch rolls but maddeningly bad. I would get two or three linked together, moving my hands and feet in a coordinated ballet, when somehow my lack of internal rhythm would intervene and I would push with the left foot when I meant to push with the right and the glider would shake itself like a dog getting up from a month old dead deer carcass. I spent the rest of the flight trying to get the footwork to link up with the stick work. I was sweating like I had been carrying the darn plane by the time we set up to land, and frankly I was so tired from concentrating that the lack of engine on final never bothered me a bit.
I ended up taking three lessons and four hours or so of airtime in the Grob and I finally got the takeoff, Dutch rolls and landings totally knocked. The best ting about learning to soar was learning to estimate the angle of descent in order to nail the landing zone. This is a lesson that serves me well every time I fly. So, I figured for sure I would get my glider ticket, and even if it was not something I would often use I would have one more credential. I had not counted on the long arm of the law and the inflexible nature of my flying budget. I really had things wired financially, enough for the ground school, teaching materials and the airtime. I had even set aside the money for the designated examiner and a celebratory lunch. However, there was not much slop. I needed to progress quickly and be soloing by hour five. My fourth ride was the pre-solo check and I was quite confident that all would go well. I am sure my instructor had faith in me as well because he seemed like a fellow who was a good judge of character and flying ability. Sadly, when I went up to Dillingham for that fourth flight he was not there. It seems that he and the FAA did not strictly see eye to eye on some exposition he had placed in a student’s log book. Something about signing off on flights where he was not actually at the airfield. I am sure there are several sides to the story, but airplane piloting is quite unforgiving in that the only side of the story that matters in the slightest is that of the FAA. They had suspended not just his CFI ticket but all his flight privileges for 90 days. The other glider operation explained this to me since the one I wanted to see was closed. The other operation was happy to take me soaring, but they would give me no credit for either the ground or the airtime and I was told it would be at least 5-10 hours before I soloed in one of their planes. This pretty well took the wind from under my wings and I have put my glider career on hold. Nevertheless this type did bring a lot of firsts: first tandem, first without electrical system, first without engine, first with speed brakes, and first plane that really made me work a the concept of stick and rudder flying. That last one was well worth the price of admission.
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