CS 25.115 Take-off flight path

(a)The take-off flight path must be considered to begin 11 m (35 ft) above the take-off surface at the end of the take-off distance determined in accordance with CS 25.113(a) or (b) as appropriate for the runway surface condition.

(b)The net take-off flight path data must be determined so that they represent the actual take-off flight paths (determined in accordance with CS 25.111 and with sub-paragraph (a) of this paragraph) reduced at each point by a gradient of climb equal to –

(1)0·8% for two-engined aeroplanes;

(2)0·9% for three-engined aeroplanes; and

(3)1·0% for four-engined aeroplanes.

(c)The prescribed reduction in climb gradient may be applied as an equivalent reduction in acceleration along that part of the take-off flight path at which the aeroplane is accelerated in level flight.