What is the trim setting when landing?

Question

What is the trim setting when landing? (Descending from 500 feet or lower) And also, when does the pilot neutralize the trim? The minute the wheels of the plane touch the ground, or when the plane is taxiing?

Answer 1

Stanley:



Remember that the objective of trim is to relieve pressure, either forward or back, on the yoke. So the pilot will be trying to maintain the appropriate speed with no pressure on the yoke (the pressure is trimmed out as necessary): approach speed (1.3 Vso) in a light single, Vyse in a light twin, and target speed (Vref + some additive) in a jet. He/She will continue to trim as is necessary to relieve pressure on the yoke right down to 50 feet or so. From 50' down, most sensible pilots just forget additional trim, and use back pressure to flare.



As for when the trim is set to neutral, probably never. Depending on the airplane, some checklists call for resetting the trim to some value after landing (usually something approximating takeoff trim), some ignore the trim altogether; it just stays where it is until it is set for the next takeoff. For instance, the B737 leaves it where it is, the B757 sets it to 4 units, the B767 sets it to 2.5 units, and the B777, like its little brother, leaves it where it is.



At my airline the after landing stuff is not done until called for by the Captain. Since taxiing is one of the more dangerous things that we do, Captains don't usually call for the After Landing Checklist until the major threats such as runways to hold short of, runway incursion hotspots, etc., have been safely passed.

Answer 2

On most aircraft you set the trim as you see fit for landing. Usually you set trim so that you don't have to hold the controls in a specific position to maintain the attitude you want. Often specific trim ranges are recommended or required by the manufacturer for take-off, but rarely for landing.



You neutralize the trim (if at all), after you're back at the gate or ramp; it's not an urgent task. You'll have to verify it and reset it before the next time you take off, anyway. You do not do it while taxiing or during rollout after landing—there are too many other things to worry about at those times.

Answer 3

The plane is trimmed down fairly far to relieve forward yoke pressure and let the pilot focus on cross-checking centerline, speed, and power settings. Once the plane has landed and has taxied off the runway, the pilot does the after-landing checklist, which includes retracting flaps and resetting the trim to "takeoff" setting.

EDIT: When I mean trimmed down, the trim tab is actually pointing up, resulting in a nose-down attitude, since the trim tab works by deflecting the elevator in the opposite direction. Regardless, the trim setting is called "nose down," at least on the Cessna 172R Nav III's I've been flying.

Answer 4

Set the trim to establish the over-the-fence airspeed you want; do this on base leg or early on final. Or you could establish the touchdown speed if you prefer. In either case, using trim to control airspeed is a good way to get it accurate, which is really what counts for landings; you need to be consistent about that to make good ones.



That means you control rate of climb or descent with throttle.



Once you have landed you don't need to worry about trim until the next takeoff. But if you're making a touch-and-go then you reset trim and carb heat before you open the throttle, since the trim for landing would be too nose-high.

Answer 5

There is no trim setting for landing. It is just whatever the pilot last set it to be.



There is no urgency to re-set the trim after landing. The after landing tasks are done whenever the captain says. --Usually after clearing the runway; sometimes while backtaxiing, sometimes when stopped after clearing the hold line.



Taking care of nonessential tasks when rolling out and taxiing clear of the runway is dangerous and a sign of inexperience.

Answer 6

hard aspect. search over google. that will could help!