AMC 22.423 Manoeuvring loads

CAA ORS9 Decision No. 1

Method I – The loads should be calculated for instantaneous deflection of the elevator, the following cases being considered:

(a) speed V_A, maximum upward deflection;

(b) speed V_A, maximum downward deflection;

(d) speed V_D, one-third maximum downward deflection. The following assumptions should be made:

(1) The sailplane is initially in level flight, and its attitude and air speed do not change.

(2) The loads are balanced by inertia forces.

The sailplanes of Category A, initial conditions of both erect and inverted flight should be considered.

Method II – The loads should be calculated for instantaneous deflection of the elevator such as to cause the normal acceleration to change from an initial value to a final value, the following cases being considered (see Figure 3).

Category U and A:
Speed	Initial Condition	Final Condition	Load Factor Increment
V_A	A₁	A	n₁ - 1
	A	A₁	1 – n₁
	A₁	G	n₄ - 1
	G	A₁	1 – n₄
V_D	D₁	D	n₂ - 1
	D	D₁	1 – n₂
	D₁	E	n₃ - 1
	E	D₁	1 – n₃

Category A – Additional cases:
Speed	Initial Condition	Final Condition	Load Factor Increment
V_A	A _-1	A	n₁ + 1
	A	A _-1	–(1 + n₁)
	A _-1	G	n₄ + 1
	G	A _-1	–(1 + n₄)
V_D	D _-1	D	n₂ + 1
	D	D _-1	–(1 + n₂)
	D _-1	E	n₃ + 1
	E	D _-1	–(1 + n₃)

For the purpose of this AMC 22.423 the difference in air speed between V_A and the value corresponding to point G on the manoeuvring envelope should be ignored.

The following assumptions should be made:

(1) the sailplane is initially in level flight, and its altitude and air speed do not change;

(2) the loads are balanced by inertia forces;

(3) The aerodynamic tail load increment is given by

Aerodynamic equation