Senator Chuck Schumer wants the Inspector General to investigate how the Federal Aviation Administration approved "doors-off" helicopter flights in the first place.

This comes after last week's chopper crash into the East River that killed five people.

The doors were open during the sightseeing tour, and the passengers were connected to the helicopter by harnesses.

"We need to know how the harness system in place received its original approval," Schumer said. "Why wasn't there an easier way to get out if God forbid there was a crash? Why did they have to instruct people to use knives? And second, we need to know what role the FAA has played in ensuring helicopters meet modern safety standards."

On Friday, the FAA announced it is temporarily restricting "doors-off" flights unless passenger restraints can be quickly released during an emergency.

An official cause for last week's crash has yet to be announced.