Gretchenfrage, SOP as such isn't a binding document that's why EU OPS has mandated OPS manual as OM A,B,C,D. OM A is an approved and the rest is accepted by authorities. Violations of those manuals under normal circumstances are offenses. Usually operators establish policies of manual compliance to protect themselves from liability. So does the manufacturer. The bottom line is the pilot is the easiest target in any case. A pilot can do him/herself a favor by simply complying with manuals.
