Daniel
667 N of force (150 lbf) in CS25
no mention of a second either:
1 The determination of the minimum control speed, VMC, and the variation of VMC with available
thrust, may be made primarily by means of ‘static’ testing, in which the speed of the aeroplane is
slowly reduced, with the thrust asymmetry already established, until the speed is reached at which
straight flight can no longer be maintained. A small number of ‘dynamic’ tests, in which sudden failure
of the critical engine is simulated, should be made in order to check that the VMCs determined by the
static method are valid.
2 When minimum control speed data are expanded for the determination of minimum control
speeds (including VMC, VMCG and VMCL) for all ambient conditions, these speeds should be based on
the maximum values of thrust which can reasonably be expected from a production engine in service.
The minimum control speeds should not be based on specification thrust, since this thrust represents
the minimum thrust as guaranteed by the manufacturer, and the resulting speeds would be
unconservative for most cases.