Landing DA40

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Hi, Philip, I am not a pilot, but my husband and I own a 2002 DA40
and I know that he has some questions about proper landing procedures
for DA40. He learned to fly in a Cessna and Piper Cub, both high wing
aircraft with much shorter wing span and he has some difficulties
landing Diamond, especially in windy conditions. One particular
question he has is should he bring the nose of the airplane up or
keep it flat/down. Also, what is the best tactic to control the plane
in gusty wind conditions? And lastly, what would you do if the plane
is purposing? Thank you very much for your help. Alla

-- Alla Swanson, April 24, 2006

Answers

To land a DA40 smoothly... Leave at least 12 inches of manifold pressure of power in (closer to 16 inches if coming down the last part of an ILS with full flaps). If you chop the power as soon as landing is assured you will develop a high sink rate. That high sink rate is tough to turn into a smooth landing. Given that fixed power setting, figure out what a 70-knot attitude looks like and then stop looking at the airspeed indicator about 100' AGL. You hold that attitude, which with the full flaps in is fairly nose-down, until you are within 5-10' of the runway. Then focus your attention at the end of the runway and begin rounding out the plane's attitude and smoothly reducing the power. As you see the edges of the runway rising in your peripheral vision, keep applying back pressure to the stick. By this time the stall warning horn should be going off, but still you keep holding the airplane off in an attempt to prevent landing. Finally, the plane will drop the last 3-6 inches and you'll have done a full-stall landing that is quite smooth. (So to answer your husband's question, the nose should come way up in the roundout/flare, to the point where you might scrape your tail skid (does no harm).)

The DA40 should not be prone to porpoising like a Cirrus or Mooney. It is a trainer, after all. If you are porpoising or otherwise involved in a major destabilization of the approach, the best practice is to add full power and go around. If you don't go around from at least 10 percent of your landing attempts, your standards might not be tight enough.

I suspect your husband is using too high an airspeed if he has enough energy to porpoise. If you look at the P.O.H. you'll see approach speeds down in the low 60s for light weights. When doing flight training (two people, full fuel), I generally use 67 knots plus half the gust factor (i.e., 67 in steady winds, 67+5 if the winds were 15 gusting 25).

Most landing problems seem to result from focusing one's gaze too close. You can help your husband by reminding him to "look at the end of the runway" as the plane sinks through 20' AGL.

-- Philip Greenspun, April 29, 2006