Figure 3
an effort to improve landing performance
or directional control; the rudder has enough authority to maintain directional control during this phase of the landing. Similarly, pushing forward on the control column after the nose landing gear is on the runway does not improve the effec-tiveness of nosewheel steering and, by reducing the weight on the main landing
gear, could reduce the effectiveness of
wheel braking.46
The U.K. AAIB said that a hard nose-landing-gear touchdown that resulted in substantial damage to a Boeing 757 resulted, in part, from the captain’s ap-parent development of a habit of applying full-nose-down elevator control on land-ing.47 The accident occurred in Gibraltar,
u.K., on May 22, 2002.
Winds were from 260 degrees at 23 knots,
and the flight crew was conducting a vi-
sual approach to Runway 27. The report
said that the approach and flare were normal, but immediately after the main wheels touched down on the runway, the airplane’s nose pitched down rapidly and the nosewheel struck the runway. None of the 175 occupants was injured, but a postflight inspection of the airplane revealed that the forward fuselage in the area of the nosewheel was damaged
Control-column Movements Recorded During Normal Landings and Landings Involving Airframe Damage
Normal landings
12 16 20 24 28 32 36 40
Elapsed Time (seconds)*
* Landings are positioned so that all reach zero feet radio altitude at the same elapsed time (28.5 seconds). Source: The Boeing Co.
substantially.
Recorded flight data showed that the captain had applied full-down elevator control during landings for several months before the accident.
“The [captain] was unaware that he had developed the regular use of full nose-down elevator on landing, although he remembers using full-forward stick oc-casionally when landing in wet or slip-pery conditions in the belief that the technique would improve braking and
control effectiveness,” the report said. “it
is possible that repetition of the control-
input sequence in the context of landing had established a habit.”
Avoid the Shock
I
n summary, a hard landing can be avoided by conducting a stabilized approach by using proper technique for handling adverse wind conditions and for conducting the flare and derotation — and, most importantly, by going around if the approach becomes unstable or if the airplane bounces more than five feet on touchdown.
If there is any reason for the flight crew to believe that the landing was hard — or firmer than normal — a hard-landing re-port should be filed so that a conditional maintenance inspection is performed to ensure the airplane’s airworthiness.
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