Engine out / Decompression ETP's/CP's
I am probably missing something but can someone explain the point of determining separate ETP's for the engine failure or decompression/emergency descent cases?
I thought that as the failure is assumed to occur at the normal ( ie. everything working as advertised) ETP then there would be no difference in the time taken to continue or return at the reduced speed corrected for the wind .
I guess what I mean is will or how will the ETP's differ for the above scenarios?
Any help greatly appreciated.