structural limitations Flashcards
Maximum structural taxi mass (MSTM) (Maximum ramp mass)
structural limitation of airplane mass or ‘authorized maximum weight’ at commencement of taxing (departure from loading gate)
Maximum take off mass (MTOM)
maximum authorized mass at the start of take off run (inc. of all weight on it such as passengers & cargo)
it would burn fuel down
Maximum structural landing Mass (MSLM)
maximum permissible mass at landing under normal circumstances
Maximum zero fuel mass
maximum permissible mass when airplane has no usable fuel
to avoid bending of wing root when fuel is consumed, it is necessary to **limit the weight **when there is no fuel in the tanks. This limit value is called Maximum Zero Fuel Mass (MZFM).
when is the highest bending moment of wing root?
when aircraft has minimum fuel
Heavy landing
Aircraft is designed to withstand landing at..
a particular aircraft weight and vertical descent velocity (the maximum is 10 ft/sec or 3.15 m/sec at maximum landing weight).
likely to have a heavy landing when
any parameters of weight or vertical descent velocity are exceeded
damage may have been caused to the landing gear or supporting structure
overstressing inlanding might be caused by
landing with drift
wrong attitude (ie landing on nose wheels/tail wheels instead of main wheels)
what loads and damage happens in heavy landing
Primary:
Affect landing gear
supporting structures in the wings or fuselage
tailplane attachment
engine mountings
secondary:
fuselage upper/lower skins and structure depending on configuration of aircraft
Nose wheel and Tail strike
Nose wheel landing can cause damage to:
* **front pressure bulkhead **in fuselage
* nose wheel strut
* drag link
* nose wheel collapse
Tail strike can cause damage to:
* empennage
* rear preasure bulkhead
