how many kms. or distance before landing a plane opens its wheels?

Answer 1

Most commercial flights with aircraft 12,500 lbs. or more fly a "straight in" approach. The most often used aid is the outer marker beacon (about 5 miles out) on the ILS approach where the pilot will extend the gear or confirm wheels down and locked if he lowered them earlier for speed control.

On light aircraft I usually extend the gear on the 45 degree approach to the downwind to fine tune speed and altitude as I enter the pattern. I then check again on base and on final as double confirmation that they are down and locked.

The most common gear up landings occur after a go-around or when there is another problem that the pilot encounters in the pattern. Light aircraft also have a back-up system that sounds a warning horn if the manifold pressure (throttle) is reduced beyond a preset point, It's not a fail safe however, because the pilot may carry extra power if landing into a stiff wind, and often you don't reduce power below the preset point until the landing flare which doesn't give you a lot of warning!

Answer 2

Leopold is correct in saying it depends on the aircraft. General aviation aircraft, those below 12,500 pounds gross weight will usually fly the traffic pattern for an uncontrolled airport. Aircraft with retractable gear are usually quite sleek, aerodynamically, and don't like to slow down, even with power reductions. The landing gear serves as a brake to help get you down to landing speeds. Going into controlled fields can often lead to straight-in approaches, as dictated by the tower. In the Cessna 421, I like to drop the gear about 5 miles out. That seems to coordinate well with the landing for me.

Answer 3

For airliners, the landing gear is typically extended around 5 miles from the end of the runway. If the pilot is high or fast on approach, the landing gear can be extended earlier in order to help slow the aircraft down or to help it descend.

Answer 4

It depends on the airplane. Primarily, you let the gear down below a certain airspeed. Generally, the landing gear would be deployed on the downwind leg of the traffic pattern, though. And (also dependent on the type of aircraft) that means the plane is close enough to the runway to make the runway, in case of engine failure, at least the way i was trained.

Answer 5

Basically, it's not a distance, but a position. Wheels are deployed at the same time as flaps, usually, as you turn onto final. There are other factors, of course, but that's about the nub.

Answer 6

when i am flying i do it around 4 miles before the runway to help slow her down