Touchdown - P-330

T-34C CONTACT

CHAPTER SEVEN

Touchdown. The touchdown is the setting of the aircraft gently onto the runway

from a landing attitude. As the aircraft settles, the landing attitude must be

maintained with backstick as necessary. If the landing attitude is not maintained, the

nosewheel will contact the ground with or before the main gear and the aircraft will

probably bounce back into the air. If the aircraft is flown onto the ground with

excessive speed in a flat attitude, the same thing will occur. These situations call for

immediate pilot action. A very hard or high bounce has only one remedy --

application of full power to execute a waveoff. A moderate skip or bounce can

usually be corrected by raising the nose to the landing attitude and re-landing the

aircraft. Failure to take any corrective action or the use of improper technique such as

chasing the nose will result in a "porpoise." A porpoise is a condition where the

aircraft oscillates in successive bounces, which usually results in an eventual severe

nose-wheel-first landing with probable damage to the nose gear.

The landing transition and touchdown should be made with the PCL approaching

idle, and the airplane at an airspeed approximately 10 percent above stall, so that the

airplane will touch down on the main gear. As the airplane settles, the proper landing

attitude must be attained by application of whatever back elevator pressure is

necessary.

Some pilots may try to force or fly the airplane onto the ground without establishing

proper landing attitude. It is paradoxical that the way to make an ideal landing is to

try to hold the airplane's wheels a few inches off the ground as long as possible with

the elevators. In most cases, when the wheels are within about two or three feet of

the ground, the airplane will still be settling too fast for a gentle touchdown;

therefore, this descent must be retarded by further back pressure on the elevators.

Since the airplane is already close to its stalling speed and is settling, this added back

pressure will only slow up the settling instead of stopping it. At the same time,

though, it will result in the airplane touching the ground in the proper landing attitude.

The T-34C should contact the ground in a nose-high attitude, with the main wheels

touching down first. After the main wheels make initial contact with the ground,

back pressure on the elevator control should be held to maintain a positive angle of

attack until it is certain that the aircraft is on the deck. Then back pressure may be

gradually relaxed to allow the nosewheel to gently settle onto the runway. This will

cause a low angle of attack on the wings to prevent floating or skipping, and will

allow the full weight of the airplane to rest on the wheels for better braking action.

The airplane should never be "flown on" the runway with excess speed.

It is extremely important that the touchdown occur with the airplane's longitudinal

axis exactly parallel to the direction in which the airplane is moving along the

runway. Failure to accomplish this not only imposes severe side loads on the landing

gear, but imparts groundlooping (swerving) tendencies. To avoid these side stresses

or a ground loop, the pilot must never allow the airplane to touch down while in a

crab or while drifting.

FLIGHT PROCEDURES 6-19