14 CFR § 29.55
Takeoff decision point (TDP): Category A
July 13, 2020
(a) The TDP is the first point from which a continued takeoff capability is assured under §29.59 and is the last point in the takeoff path from which a rejected takeoff is assured within the distance determined under §29.62.
(b) The TDP must be established in relation to the takeoff path using no more than two parameters; e.g., airspeed and height, to designate the TDP.
(c) Determination of the TDP must include the pilot recognition time interval following failure of the critical engine.
[Doc. No. 24802, 61 FR 21899, May 10, 1996]