Thanks OzExpat, that pretty much said it. One of the major areas of concern in designing OEI escape routes is the scenario where the engine fails AFTER that point in the flight where the SID and the OEI Special Procedure deviate, and obstacle clearance is not yet ensured.
The solution that I apply to the problem in those departures where obstacles during the SID are excessive is to devise 2 sets of RTOWs for the same runway, one to follow the SID, and the other commited to the Special Procedure.
(1) If the Actual Takeoff Weight is at or less than that which would comply with engine failure during the SID, then fine, accept the SID.
(2) If the Actual Takeoff Weight EXCEEDS that for compliance with the SID (but obviously at or less than that for the Special Procedure), advise ATC that the SID is not acceptable, and advise of your requirement to follow the Special Procedure routing until MSA is reached.
That's the data that I give to 'my customers', others may do it differently, Mutt, John_T?
Regards, and Compliments of the Season,
Old Smokey
That is a very good solution. I don't know if all airlines has a performance sheet that gives RTOW with reference to the SID. It could be very useful. Of course, the Takeoff Analysis have of sure the Field/climb/obstacles/ items, but, as mentioned before, they refer to 1 ENG OUT at V1 with related 1 ENG OUT procedure built by the Airline (it's an airline's liability by ICAO DOC 8168). I also noticed that on my B737 manuals (TR manuals, not employed yet) there aren't tables with the Vertical Speed performance or the gradient that the airplane could achieve!
Many friend of mine pilots replied to my question with "hey guy, it's a Liner, it always stay within the gradients of the SIDs...." (that is not the reply I was waiting for...)
Thanks
Davide