Relevant information is also here:
AC No: 25.1329-1B - APPROVAL OF FLIGHT GUIDANCE SYSTEMS
Pages 71- 72:
a. Takeoff Mode.
(1) Vertical Guidance. In the Takeoff mode, the vertical element of the FGS
should provide vertical guidance to acquire and maintain a safe climb out speed after
initial rotation for takeoff.
(b) Pitch Attitude and Climb Speed/Normal Operation. The vertical axis
guidance of the takeoff system during normal operation should result in the appropriate
pitch attitude and climb speed for the airplane considering the following factors:
2 The system should provide commands that lead the airplane to
smoothly acquire a pitch attitude that results in capture and tracking of the all–engine
takeoff climb speed, V2 (takeoff safety speed) + X. X is the all-engine speed additive
from the AFM (normally 10 knots or higher). If pitch limited conditions are encountered,
a higher climb airspeed may be used to achieve the required takeoff path without
exceeding the pitch limit.
(c) Engine–Out Operation. For engine-out operation, the system should
provide commands that lead the airplane to smoothly acquire a pitch attitude that results
in capture and tracking of the following reference speeds:
1 V2, for engine failure at or below V2. This speed should be attained
by the time the airplane has reached 35 feet altitude.
2 Airspeed at engine failure for failures between V2 and V2 + X.
3 V2 + X, for failures at or above V2 + X. Alternatively, the airspeed
at engine failure may be used, provided it has been shown that the minimum takeoff
climb gradient can still be achieved at that speed.