WASHINGTON - Government planes and helicopters are used every day to help protect public safety, as well as countless other tasks. But who is looking after the safety of the flight crews, government employees, and other passengers on those aircraft?

No one, the National Transportation Safety Board said this week.

The Federal Aviation Administration says it doesn't have the authority to regulate the safety of aircraft operated by other federal agencies or state and local governments. And those government agencies, with the exception of the military, generally do not have the aviation expertise to do it themselves.

That makes these aircraft - some government-owned, others leased - virtual safety "orphans," said NTSB chairman Deborah Hersman. Someone, she said, needs to accept this duty.

The issue came to the fore Tuesday when the safety board determined after a two-year investigation that a company that provided a helicopter to the U.S. Forest Service for firefighting was responsible for a crash that killed nine people, including seven firefighters, and injured four others in a mountaintop clearing near Weaverville, Calif.

The board said Carson Helicopters of Grants Pass, Ore., falsified documents to overstate the performance capabilities of its helicopters to win Forest Service contracts. As a result, the Sikorsky S-61N helicopter's pilot underestimated its weight by more than 1,400 pounds while preparing to ferry firefighters from the front lines of a stubborn wildfire in the Trinity Alps Wilderness on Aug. 5, 2008.

The chopper was airborne less than a minute when its rotor began to slow. It clipped a tree and fell from the sky, bursting into flames.

Even so, there might have been fewer deaths if the helicopter had been equipped with sturdier fuel tanks less likely to rupture on impact, the board said.

The installation of cabin seats that were not crash-resistant and seat belts with a complicated rotary release mechanism, instead of the typical lift-latch release used in airline seat belts, also contributed to the fatalities, it said.

The FAA certified the helicopter, which was also used for nongovernment work, for flight without inspecting it, investigators said. FAA officials who oversaw the safety of Carson's nongovernment-related operations had several opportunities to detect the falsified documents, but failed to do so, investigators said.

The Forest Service awarded Carson a leasing contract without verifying the company's claims about the payloads its helicopters were capable of lifting, even though other helicopter companies told investigators those claims were suspicious.

Carson has notified the FAA that it is surrendering its operating certificate. The company said its own investigation showed the crash may have been caused by a faulty fuel mechanism that caused one of the helicopter's engines to lose power. NTSB said both the chopper's engines were working at the time of the accident.

The FAA said it was "working on policy clarification" for inspectors who oversee companies that lease aircraft for both government and private use.

The General Services Administration, which makes recommendations to federal agencies on air fleet management, said the FAA is responsible for the oversight of aircraft used solely to carry passengers. But the FAA doesn't regulate aircraft engaged in government activities, such as firefighting, border patrol or chasing crooks.

"Why is there a separate standard for these brave young men out there protecting homes? Why is the safety standard less for them than when you and I get on a commercial airline?" asked Catherine Renno of Cave Junction, Ore., whose son, Steven Caleb Renno, was killed in the crash.

As a result of their investigation, NTSB officials are now asking if other companies that lease planes and helicopters to government agencies are engaged in "a race to the bottom" to maximize profits.

"What we don't know is: Are there other operators out there right now also providing inaccurate information to flight crews and the FAA?" said Thomas Haueter of NTSB's Office of Aviation Safety.

Federal agencies operate more than 1,600 nonmilitary aircraft. State and local governments operate hundreds more.