Is engine failure on the runway at takeoff the most limiting case

Diverging All Engine Standard Instrument Departures (SIDs) and Engine Out Standard Instrument Departures (EOSIDS) paths in Commercial Large Aircraft Operations have always been an intractable problem which has resulted in over simplified escape paths that do not fully cover the full intent of aircraft regulations. SIDs are designed and implemented for the normal flyaway case, as such they do not take into consideration a degraded climb performance that occurs with a failed engine. On the contrary, EOSIDs are solely defined for safety of flight and therefore consider degraded climb performance. Our new modeling capability on SIDs and EOSIDS has revealed unforeseen paths that appear to challenge the notion that the worst possible engine failure case always occurs on the runway. Furthermore, it has highlighted lack of guidance in regulations that leave operators on their own to provide practical guidance to their Flight Crews.