The Pilot's Lounge #130: Competition Spot Landings
Just Another Checkout Flight?So it came to pass that I was soon in the right seat of a late-model 150, sitting quietly, while Sandy renewed her acquaintance with the airplane. After some time aloft going through steep turns and a stall series, she said it was time to return to the airport and do a half-dozen or so spot landings. I expressed concern that my weight would adversely affect her practice should she be solo at the competition. She told me she would have a passenger, so it shouldn't be a problem. Nearing the end of the downwind leg, I found myself preparing for Sandy to do something akin to the spot landing required in the Commercial pilot practical test, what the FAA refers to as the "Power-Off 180-Degree Accuracy Approach and Landing." The target is considered to be a trench across the runway. The applicant is expected to land, on centerline, beyond the "trench," but as close to it as possible, and no matter what, within 200 feet. The procedure is generally to treat it as an advanced version of a forced landing. The pilot will close the throttle opposite the point of desired touchdown, slow to best-glide speed, turn base fairly quickly, and start deploying flaps as needed. The pilot will adjust the turn to final based on how things are going, so as make a normal, power-off landing just past the line. Any combination of flaps and slips is allowed in the process of alighting where desired. I'd been doing and teaching spot landings for years, and I was usually happy to be able to come within the 200-foot margin of error. I, and countless other instructors with whom I had associated, tended to unconsciously group the skill for a spot landing with the group of Commercial maneuvers that included gliding spirals, forced landings and accuracy landings. They were to flow together in the real world: Once a landing site is selected, descend at approximately best glide speed (so as to avoid the cardinal sin of squandering altitude), position the airplane at roughly pattern altitude, on downwind, just opposite the landing point, and then touch down, on the spot, as slowly as possible (but without stalling) so as to minimize the energy to be dissipated once on the ground. I never differentiated the technique for a forced landing from that for a spot landing. Over the years, I had happened upon a few spot-landing competitions, and I noticed that the organizers usually added an extra rule or two to the Commercial accuracy landing procedures, most often requiring that once flaps were extended they could not be retracted at all. (There are some contests in which power is allowed on the approach, but Sandy advised me those are considered to be only for airplane drivers who also had difficulty getting past the training-wheel stage with their bicycles.) At the spot-landing events in which I had participated, I had behaved according to habit, treating them as the Commercial maneuver, and had been happy when I landed beyond, but within, 200 feet of the mark on the runway. It is a trifle embarrassing to admit that the only time I won a spot-landing contest at a fly-in was when I was merely arriving and had no idea there was a contest. I had landed on the grass runway in use. Upon getting out of the airplane, I was told I had touched down a matter of mere inches beyond the line. I had never seen the line. As we came opposite to our touchdown spot, Sandy pulled on the carb heat and closed the throttle. I settled in to watch yet another simulated, forced-landing/accuracy-landing procedure unfold. I think I yawned. Sandy blew my calm expectations to smithereens.
Not Just The Old Commercial ManeuverIn a matter of a minute or so she taught me that competition spot landings should be an Olympic sport, that they were only a distant cousin to minimum-energy forced landings, and that even I could learn to touch down within a few feet of a line marked on a runway. The only thing she did that I expected was to pull the power back to idle opposite the touchdown spot and let the airplane start to decelerate. As soon as the speed was inside the white arc, she dropped 10 degrees of flaps, while commenting, "I like electric flaps for this because you're not limited to detents and can make very small changes." Rather than target the 60-knot best-glide speed for the 150, she settled on 70 KIAS while telling me that, if it were really windy, she might increase the speed by five or even 10 knots. I was too amazed to say anything. After losing about 100 feet, Sandy made a very deliberate turn to base leg. It wasn't a steep bank, but she didn't fool around, getting established with the nose pointed slightly toward the runway, crabbed just right for the crosswind. "OK, on base, we keep the speed up, at least 70, and start judging how things are going. The wind is pretty light, so I'm going to aim about 400 feet short of the line, about two runway lights. If it were windy, I'd aim to come into ground effect a hundred feet or so closer to the line. I'm also going to make sure I keep my speed up because I want to reach ground effect with enough speed that I can put the airplane anywhere I want." The airspeed indicator needle stayed pegged on 70 KIAS as Sandy dropped about five degrees more flap. "Right now, I use just lift flaps, 20 degrees or less, and am watching to see how we look on the glide path I want. In some of the competitions, you can't add any more flap once you turn final ... never have figured out the reason for that rule, but we'll pretend it's in play today. If I feel like I'm high, I'll get into the drag flap range -- more than 20 degrees -- but not until I'm in the turn to final. You don't believe in that old wives' tale about not adding flaps in a turn, I hope?" I allowed that there was nothing wrong with adding flaps in a turn; good grief, it's actually a good way of taking advantage of the behavior of those airplanes that pitch up with flap extension.
Fast FinalSandy kept looking out the window and providing me with a commentary, "All right, things are looking about the way they should, so we'll make a normal turn to final. If we were low, we'd turn early and aim straight for the runway; if we were high, I'd get more flap out and slip and delay the turn to final so that I'd make the turn past the runway and come back to make us travel further." On final, where I would ordinarily be holding about 55 or 60 KIAS with the just under 20 degrees of flaps Sandy had extended, she still had the speed nailed on 70 KIAS and we were noticeably below the glide path (and low in the sight picture I was used to seeing). Sandy was unperturbed, "We've got at least 10 knots of extra speed and I'm going to take advantage of ground effect with it." We came into the flare well short of the line, so much so that I was convinced we going to plop down ignominiously before it. I was starting to think of placating things to say: "Hey, it's been a while since you flew one of these," or, "Yeah, the first one is where you start getting the feel for what's going on." I never got a chance to use them. Sandy held the descent right to flare height, then raised the nose gradually until the airplane was less than six inches off the runway. She held the airplane right there, pitch attitude slowly increasing as the speed gradually bled off and we ate up runway toward the line. As the line was about to disappear under the nose, the airplane began to settle. As I learned moments later, Sandy had slightly relaxed her back pressure on the yoke. The wheels touched and the airplane stayed on the ground. In a moment, Sandy had snapped the flap switch up, was pushing the carburetor heat knob to cold and opening the throttle. The nosewheel never touched the ground as deceleration ended, acceleration took over and we lifted off.
How'd You Do That?I was flabbergasted. As we climbed, Sandy explained, "Ground effect breaks up wingtip vortices, so the effect is to reduce drag. I just take advantage of it. When I'm holding altitude a little bit above the runway, even going as fast as 70 knots, the nose is high enough that if I put the mains on the runway, the nosewheel isn't going to touch. So I'm in landing attitude as soon as I break the descent. Then it's just a matter of holding the airplane just barely off the ground, which is something that you learn how to do pretty fast, and waiting until I'm almost to the line and then relaxing back pressure so that the airplane descends those last few inches to the runway. Figuring out when to relax the back pressure is just a matter of some practice and developing a feel for the rate at which you're coming up on the line. It took me a bit to learn not to flinch and pull back on the yoke when the wheels hit so I didn't bounce back into the air. When you bounce, they measure the landing at the spot where you finally touch down and stay down. "This is different from normal landings because you don't try for a real smooth landing -- you want to touch down firmly and stay on the runway. In the serious competitions, they put white paint on opposite quarters of the tires so they look kind-of like a checkerboard and the judges can tell when they start to roll; a smooth landing can actually be a bad thing, as the tires may slide just a little before they start to turn and you get marked that much farther from the line. This isn't like a forced landing or even a normal landing, because you aren't trying to touch down as slowly as possible. I've read that stuff you call a column and I know you harp on being "on speed" on approach and touching down as slowly as possible to so you don't have as much energy to manage during the rollout. You aren't right about much, but you are about that, and I know that extra speed is the reason most landing accidents happen. However, for this particular kind of competition, what matters is where I touch down, and I'm ready and willing to keep using the flight controls to keep the airplane going straight after I'm on the ground. I'm aware of the risk of touching down fast, so I prepare myself to deal with it. "The reality of competition spot landings is that, if I mess up and I'm high enough that I come into ground effect pretty close to the line rather than a few hundred feet before it, I can to touch down at 70 knots if I need to. As long as I don't have more than about 20 degrees of flap out, the nosewheel isn't going to touch the runway. But, since I'm aiming to flare well short of the line, I'm going to be slower than 70 knots when I come up on it. How much slower depends on the wind, how well I regulated my glide angle and where I flared. If I get low on approach, I'm still going to keep going fast until I get into ground effect, because I want to take advantage of the reduced drag and hold the airplane off the ground as long as I can. Even with a pretty good headwind, I can float a ways down the runway. "In ground effect, a 150 isn't going to stall until the airspeed is indicating somewhere around 40 knots, so I've got a pretty big speed margin to play with. Slowing from 70 indicated to something around 40, in ground effect, uses up a fair amount of runway. If you think about all those pilots who come in fast, float a long ways and then run off the end of the runway, you get a feel for what ground effect does and how you can make it work for you by flaring well short of the touchdown spot. What I'm doing in competition is a little bit like intentionally making a bad landing, in that I'm going too fast on final and then floating in ground effect. However, I'm doing it on purpose, with my eyes open. And if I blow it, and somehow float 200 feet past the line, I'm going to go around. There's no sense in landing, as I'm out of the competition, so I'm not at risk of landing long and being unable to stop." I rode with Sandy through several more landings. From where I sat, she seemed to be touching down between two and 10 feet past the line. She was very consistent in her touchdown spot, even if she was a somewhat long or short of the point where she wanted to come into the flare. After she decided that she had gotten the feel of things, she let me try a few. I wasn't as close to the line as she, but I was consistently far, far better than I'd ever been before. It was a revelation. Oh. Since I flew with Sandy, I won a spot-landing competition. OK, OK, so she wasn't competing in it ... See you next month.
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