Page 501 - PPL-engelsk 2025
P. 501
Principles of flight
If the limit load factor is exceeded by 50%, the aircraft is at the ultimate load
factor, where there will be breakage or visible signs of shape changes.
The limit load factor must never be exceeded. Permanent
deformations can occur!
It is not certain that you can see the deformations immediately, but the metal
never forgets - the pilot may do so!
If the ultimate load factor is exceeded, the aircraft structure will visibly break!
5.8.2.2 Relationship between load factors and damage to aircraft
The illustration here shows the relationship between the influence of G-force
and the consequences of exceeding the limit load factor / ultimate load factor.
Pilot A makes a loop in his
plane.
He sees the skin on the upper
side of the wing wave and
eases the pull on the stick.
Since the plane is no longer
loaded, the waves straighten
out, and the wing is as before.
Pilot B also makes a loop but exceeds the limit load factor.
Permanent deformations occurs on the plane.
Pilot C also makes a loop, exceeds both the limit load factor of 3.8 G and the
ultimate load factor of 5.7 G. Parts of the plane breaks off, so there is only one
way out, the parachute, if you have one!
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 501
