Like the rest of the country, I was deeply saddened by the fatal crash of an emergency medical services helicopter in Rochelle, Ill., that killed three people. But as a former chairman of the National Transportation Safety Board, I was not shocked by the catastrophe.

EMS helicopters — sometimes known as “angels of mercy” — are among the most dangerous aircraft in the skies. According to an NTSB report, 2008 was the deadliest year for helicopter emergency medical services, with 12 accidents and 29 fatalities. In 2007, EMS helicopter crew members were found to have the highest fatality rates of all occupations.

In 2010, the FAA took steps to mitigate risk in EMS flights by implementing stricter safety guidelines but stopped short of embracing the recommendations of the NTSB. Clearly, as the Dec. 11 crash indicates, not enough is being done.

What I fear is that, as the facts of this accident are learned, it will be revealed that it was caused by lessons previously learned and ignored; that would make this a double tragedy. According to investigators, the helicopter communicated that it had encountered inclement weather and was turning around. Ten minutes later, a ground dispatcher attempted to reach the chopper, but it had crashed in a nearby field.

The causes of the crash are still being investigated by the NTSB, but similar accidents could be prevented by requiring all EMS helicopters to have two active pilots at night. When a pilot is operating an EMS chopper and is the sole pilot, having to work the radio while maneuvering the aircraft in questionable conditions is not a simple task. Pilots can sometimes run into severe patches of fog or icing, and these conditions — a solo pilot flying a helicopter in inclement weather — are some of the worst a pilot could ask for, yet EMS helicopter pilots are required to operate in them all the time.

Another way to prevent accidents is to ensure that these helicopter pilots have current, accurate and local dispatch information. In this case, a local dispatcher may have had the ability to foresee the poor flying conditions along the route of flight and prevented the crash.

It is unclear to me why the FAA continually puts off taking significant steps to improve the safety of EMS helicopters. Surely, if commercial airliners were to crash at the rate that EMS helicopters do, something would be done. And it has — we have not seen a commercial aircraft crash in nearly four years. Making these improvements to the helicopter EMS industry will bring better service and save the lives of people who are trying to do the same for their patients.

The underlying principle that should govern EMS helicopter operations in simple: when a patient is evacuated by helicopter, there should not be additional risk of injury or death because of shortcomings in the safety culture associated with these operations. I have always viewed that the government should embrace the philosophy of Thomas Jefferson: “The care of human life and happiness is the first and only legitimate object of good government.”

Sadly, as the tragedy in Rochelle highlights, our government does not consistently endorse this philosophy, but chooses to allow a series of accidents to go without any regulatory response.

Jim Hall was chairman of the National Transportation Safety Board from 1994 through 2001. He is the managing partner of Hall & Associates, a crisis-management and government-relations firm based in Washington.