Originally Posted by
AerocatS2A
When all engines are operating you follow the SID and must comply with the SID climb gradient. If you lose an engine then the SID no longer applies, you follow the engine out procedure and don't have to comply with the SID climb requirements because you aren't following the SID anymore.
An EO procedure is not something a SID has, it is something your company has worked out, or paid someone to work out, for your departure runway.
The fun starts when you have an engine failure after your SID deviation point. I worked for a while in a place where in mountainous terrain the EO procedure would often be different from the SID starting from the departure end of the runway. If the engine failure happened after V1 you followed the EO procedure. The company maintained that was legal because “if you have an engine failure at the most critical point, which is and will always be V1, you have a way out.” . My point was, if I have an engine failure after the point where the EO procedure and SID deviate, I will be stuck on the SID, without the required climb performance. To me this made the SID deviation point the most critical point, and not V1. Luckily we operated in non radar, and the controllers were very flexible, so I would always fly the EO procedure until above MSA/MORA, and then pick up the SID again. It took a while for the company to adjust the numbers to guarantee obstacle clearance if the engine failure happened after the SID deviation point.