DOHA, Qatar (AP) — A senior official at an organization representing the majority of airlines worldwide said Tuesday there is no specific timetable for implementing new tracking recommendations following the disappearance of a Malaysian aircraft with 239 people aboard in March.

Discussions about real-time tracking and airline safety have featured in many sessions of the International Air Transport Association’s annual meeting, held this year in the Gulf-Arab nation of Qatar. That’s because passengers and even experts continue to wonder how an aircraft can just disappear without anyone knowing what went wrong.