It is a good discussion.
I find it very disturbing to read here and there of pilots who want to 'reinvent' the OEI procedures, break off and head out to sea, or attempt to follow the SID. How well did the proponents of such ideas survey the new field of obstacles in doing so ?
Obstacles are assessed very accurately for OEI Special Procedures, and the optimum path chosen. They have to be, margins of obstacle clearance to comply with FAR25 (or it's equivalent) are EXTREMELY small, and small obstacles that wouldn't cause a moment of consideration for crews familiar with a particular airport during normal operations can become critical.
Consider a 100 foot radio mast at 1 nautical mile from the departure end of a 3000 M runway. At the line-up point, can you accurately assess this mast at a distance of 4.8 Km, a mere 1/3 of a degree above the horizontal to the pilot's eye position ? Well, it's a critical obstacle for a 2 engined aircraft at performance limiting weights. So too is a 6 foot man at 1000 feet from the runway end. Now put these same 'indiscernable' obstacles in the 'reinvented' OEI route for those who want to take another route and see the outcome. As I said in an earlier post -"it's not usually the obvious big obstacles that are 'gonna getcha', it's the little subtle ones".
I see cynical remarks in these posts regarding procedures to squeeze the last possible Kilo of payload. Do these same cynics realise that if the performance engineer has chosen a route that obtains those last few kilos of payload, that this must imply that that is the path with the LEAST obstacles, and is therefore the SAFEST. This is one of those rare cases where if you choose the SAFEST option in terms of terrain clearance, then it is also the most commercially viable. A rare marriage.
DFC, you made the statement -"Could it be that the person who approved the procedure in the ops manual (Chief Pilot?)...etc", The procedures are created by performance engineers poring over incredibly large scale survey charts, municipal maps, etc...stuff that is not available amongst normal aeronautical charts etc. These fall far far short of adequacy to evaluate safe routes for OEI procedures. It is a full time job for P/Es and their staff.
It is acknowledged that there are some lousy procedures "out there", but properly designed procedures get you all the way up to MSA, and DO consider high density traffic areas etc., including the shipping alluded to by OzExpat. Do the OEI reinventers consult the shipping authorities to ascertain the largest vessels able to use over-water areas envisaged ? I do. Again, the 'lousy' procedures stick you with one single procedure, often incompatible with the SID. A good service provider will supply OEI data to comply with the SID (usually much more restrictive), in addition to the optimum data over an optimised route, which, if required for your actual Takeoff Weight, must be advised to ATC.
OEI procedures are created by, and provided by the operator (or the operator's sub-contractor). There is a good case to canvass, at ICAO level, for standard, optimised, OEI escape routes for all runways. Until that time, it is an issue that pilots must take up with their management, or their performance engineering departments.
Until that time, for God's sake, for your sake, for your passenger's sake, follow the OEI published procedure.
Please.....I might be one of your passengers.
Old Smokey