Q-talk 101 - Fly It On
- Category: Q-Talk Articles
- Published: Wednesday, 23 December 2009 16:24
- Written by Dave Richardson
- Hits: 2530
People who share common experiences can sometimes create a special language full of abbreviated terms and references. This language is understandable for all those "in the know". The situation can present a real language barrier for those unfamiliar with the terms.
1 have to admit that the phrase, "fly it on", when referring to the landing of a Q, has been one of those mystery references for me. Just what does "fly it on" mean? The phrase only contains three words and each word only has one syllable. It should be easy, right? As I prepare for the first flight of my Tri-Q2, I have given this phrase a lot of thought. I believe I have finally discovered what they have been talking about. The concept is not extremely complex.
I am going to assume that you have had at least some Cessna experience and have successfully landed them many, many times. Do we share that common experience? In the Cessna "Land-o-Matic" trainers, (150/152/172) equipped with large wing surfaces and flaps, you increase your "over-the-nose" visibility by lowering the flaps, which, in turn, lets you lower the nose without increasing the airspeed as you proceed down the glide path. By the time you have full flaps deployed, you feel like you are wheel bar-rowing through the sky with your tail really high relative to the nose. As you get closer to the ground, you need to transition the plane so the "expensive-if-you-break-them" parts found on the front of the plane, like the propeller, engine and the nose gear, will no longer be the first things to make contact the runway. The wheels of the main gear are targeted as the desired point of contact. Most people call this transition a "flare", one of those abbreviated references.
The goal of landing a Cessna, or a Q for that matter, is to land the plane as gently as possible, given the conditions of the runway. The common way to do this is to bring the plane in at a very low rate of speed, let it stall and then sink slowly onto the runway. The important factor is to make this stall/sink event happen very, very close to the ground. If you stall ten feet above the runway, you may not have enough altitude to recover before you hit the runway. If you have too much energy when you initiate your flare, you will just float down the runway. Too little energy, you will fall short of making the runway all together.
While flying a Q, several aspects of the landing sequence differ from the Cessna experience and require a different approach. (Sorry for the pun.) With a Q's short wings and high weight to wing surface area ratio (high wing loading), Q's need to land at a faster rate of speed to avoid a "pitch buck" (abrupt nose down recovery when the canard stalls but the main wing keeps flying) when close to the ground. The goal is the same as the Cessna where you want to land the plane as close to the stall speed as possible. The difference is the stall speed is higher on a Q and the Q's lack of lift enhancing devices (flaps) means you are stuck with the higher Vs (Velocity - stall - clean configuration). Ultimately, the nose of the Q needs to rise up enough to get the expensive parts out of the way and expose the main gear to the runway without getting the nose so high that the canard stalls, bringing the nose down quickly onto the runway. There have been a couple of people who have measured the angle relative to the level waterline built into their armrests at different airspeeds and they have found that the angle near their stall speed was in the vicinity of 14 degrees. So, you can fly your Q at speeds just above the stall speed and your nose will be fairly high in the air.
In the time honored book, "Stick and Rudder" by Wolfgang Langewiesche, the author emphasizes a concept that directly relates to our topic but requires some airmanship to execute. He points out that pitch controls your airspeed while throttle controls your altitude. While this might seem strange, you can easily prove this to yourself in an imaginary flight. If you push the stick forward, you are going to go faster. If you pull back on the stick, you are going to go slower. To take off and climb, you need to push in the throttle. Pulling the throttle to idle will certainly result in a descent. So, when you fly slowly, your nose will be raised. By raising the nose and reducing the power, you will descend. As you descend, you can control your airspeed with the elevator and your rate of descent with the throttle to some extent.
Cessna and similar trainers have refined their wing designs over the years to have gentle stall characteristics where the stall begins at the root of the wing and slowly migrates outboard over the long wings. In the flare, when the Cessna pilot rotates the nose up, they can keep pulling back on the yoke until the elevator is almost against the stop and the yoke is in the pilot's lap before the stall occurs. In a Q, things happen much faster due to the short, general wing design. The pitch buck stall can be fairly abrupt and less forgiving when performed close to the ground. This situation should be avoided.
While flying a Q2, you can establish a speed not too far above the stall speed, like 90 mph and your nose will be fairly high, in the order of 8 to 9 degrees. In a single place Quickie, 70 mph may give you similar nose high results. This position can be maintained while controlling a reasonable decent rate with the throttle. This allows your airspeed to be above the stall speed of the plane and the prop, etc. is out of the way as you get close to the runway. In essence, you are pre-flaring the plane and controlling the descent rate with the throttle. You maintain that nose-high attitude and fly it all the way down to the runway. In the Cessna, when you are several feet off the runway, you would normally yank back on the yoke so you can get the nose up and the plane slowed down so it will stall when you are close to the ground and sink onto the runway. In your Q, you are going to continue on in at the same nose-high attitude until you, as Sam Hoskins puts it, "fly in close formation with the ground" and then you let it gradually descend until it literally "flies onto the runway." This way you land above pitch buck speed and your prop tips are the same length as when you took off. Some pilots have told me that they do some very minor flaring as they get within a few feet of the runway in an effort to bleed off some airspeed and land as gently as possible. This would be better described as a mini "round out" that is an attempt to slow the plane down to get closer to the stall speed than a true flare as their plane is already in a landing position. By coming in above the stall speed, you leave yourself a margin of airspeed that you can bleed off during this mini round-out and aid in flattening out your descent when you are close to the runway.
You have probably seen examples of this type of landing many times and did not realize it. Most modern Navy fighter pilots employ a beastly version of "fly it on" when they land on aircraft carriers. Their nose is high, their tail hook low and they dial in lots of power so they do not require a flare over a rolling deck. In fact, they depend on power so much that if their engines go, they have to punch out (eject) because they're hanging in the air like Sean D. Tucker doing a Harrier pass. Keep in mind, though, these Navy pilots put their lives at risk when they precisely collide with the deck as they hope to catch an arrester cable.
They must keep plenty of power applied in case their attempt turns into a crash-n-go and they have no deck to roll down while waiting for Vr (Velocity - Rotate) to occur. Former naval aviators warn the pilots of fast glass experi-mentals that attempting to only control their descent with throttle will get you into trouble, especially when they do not have a working engine. They also remind us that the Navy aircraft are designed to take the punishment of this type of landing while our planes are not.
At the other end of the spectrum, Jerry Marstall described his very civil "fly it on" approach in his Tri-Q2 as pulling the power to idle abeam the numbers on downwind and he does not touch it again until he has turned off the runway and power is needed to taxi the plane. To do this, he maintains precise control of his airspeed with elevator. Obviously, this requires a lot of experience and practice to manage the energy so efficiently.
Somewhere in-between these two extremes, Paul Fisher passed along some good advice that he received from a flight advisor and 600+ hour Q200 pilot, Barry Weber. He suggested maintaining 1300 rpms all the way to the ground when landing the Q200. Paul said he did not even attempt to land his plane any other way for the first 50 hours. By leaving some throttle in during the landing, you can help from making the sink rate too high causing you to pancake into the runway.
It comes down to the fact that there are many different engine/plane configurations and experience levels out there and each combination is going to require a slightly different approach strategy. There are plenty of flying examples of each of these combinations. If at all possible, try to get enough time in type to work out your own strategy and feel comfortable "flying it on" the runway. Single place Quickie guys will benefit from time in Q2 or Q200, too.
In summary, when you "fly it on", you lock in the nose-high attitude on final by maintaining your airspeed with your elevator and then bring the plane all the way down onto the runway, or down to within inches of the runway and raise the nose some more to bleed off any excess airspeed. You try to make the softest landing possible without doing a pitch buck stall.
If this is a new concept for you, give this technique a try. With an instructor's help, "fly it on" in the type of aircraft in which you are current until you get the feel for the landing and then practice the skill often. It will pay off.
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