The limit drop test must be conducted as follows:
where:
We = the effective weight to be used in the drop test (lbs.).
W = WM for main gear units (lbs.), equal to the static reaction on the particular unit with the rotorcraft in the most critical attitude. A rational method may be used in computing a main gear static reaction, taking into consideration the moment arm between the main wheel reaction and the rotorcraft center of gravity.
W = WN for nose gear units (lbs.), equal to the vertical component of the static reaction that would exist at the nose wheel, assuming that the mass of the rotorcraft acts at the center of gravity and exerts a force of 1.0g downward and 0.25g forward.
W = Wt for tailwheel units (lbs.) equal to whichever of the following is critical-
h = specified free drop height (inches).
L = ratio of assumed rotor lift to the rotorcraft weight.
d = deflection under impact of the tire (at the proper inflation pressure) plus the vertical component of the axle travel (inches) relative to the drop mass.
n = limit inertia load factor.
nj = the load factor developed, during impact, on the mass used in the drop test (i.e., the acceleration dv/dt in g's recorded in the drop test plus 1.0).
14 C.F.R. §29.725