@PIK3141 (post#3)
You are basically correct. Perhaps it is useful to clarify that the limiting obstacle is likely to be significantly lower than 500 ft. The accel height on the RTOW chart is the gross acceleration height. The net acceleration height has to clear obstacles by 35 ft and is less than the gross height. How much less depends on the particular conditions.
@Brotti:
the max Accel Alt equals 10 min@toga
That is correct for airplanes which have obtained approval for the use of 10 minutes of TOGA after failure of an engine in takeoff, otherwise it is 5 min@toga. There is no specific requirement reference for that. The scheduling of performance data normally assumes that cleanup and acceleration to final takeoff climb speed is conducted with takeoff thrust or power. Hence it must be completed before the time limit for the use to TOGA is reached.
@hvogt:
Publishing a maximum acceleration altitude in the AFM might be a requirement according to CS 25.1585
No, I don't think it is. The time limit(s) for the use of TOGA are limitation(s) that must be stated in the AFM Limitations section in accordance with CS 25.1521(c)(1)(ii). The net takeoff flight path data in the AFM Performance section required by CS 25.1587(b) must respect that limitation and will usually schedule the maximum acceleration altitude as a function of operational variables such as weight, altitude, temperature and configuration, as a 'limit of validity' of the net takeoff flight path data. The net flight path data is information provided in the AFM to permit compliance with operating rules such as FAR Part 121 or EU-OPS that contain obstacle clearance requirements.