The main difference between responsibility and Accountability is that responsibility can be shared while Accountability cannot.
Accountability is a security goal that generates the requirement for actions of an entity to be traced uniquely to that entity. This supports non-Repudiation, deterrence, fault isolation, Intruder Detection and prevention, and after-action recovery and legal action. (NISTIR 7298)
Accountability is accepted where Responsibility is assigned.
He may or may not be the responsible party that perhaps caused a collision. (ie the co-pilot may have been the responsible party).