The biggest American casualty from the raid on Osama bin Laden's compound last week was a multi-million dollar secret helicopter that dropped 30 to 40 feet in the air onto the hard ground.
It took a while for all the details to emerge, but it appears the crash happened for one really surprising reason: The air on ground was much hotter than anticipated. That, combined with the high walls of the compound, created an air vortex that sucked the air right out from under the chopper. A mission that should have started with the U.S. Navy Seals rappelling into the yard instead began with a hard thud. The fact that a helicopter failed during the mission was one of the least surprising details of the raid.
Part of the problem is perception, says Dr. Ira Blumen, an emergency medicine doctor at the University of Chicago who has researched accidents with medical transport helicopters. The military tends to use Black Hawks and Chinooks to transport large groups of people, so when there's an accident, it gets attention.
"Any time you have a helicopter accident, it's big news," he says. "It's more dramatic than a car accident ... And the higher profile the mission, the higher profile there will be when there's an accident."
Maybe too many people are familiar with the 2001 movie, "Black Hawk Down," which depicted a Black Hawk helicopter taken down by RPG's over Somalia.
Or maybe there really are too many helicopter crashes.
Congress is wondering what's up, too. They ordered the Department of Defense to look into helicopter failures in combat and figure out how to curtail crashes. Since 2001, 496 people have died in military helicopter accidents, according to a Department of Defense presentation given last October at the International Helicopter Safety Symposium.
Helicopter crashes are the third leading cause of death in the Iraq war, behind IED explosions and direct fire attacks. Surprisingly, the majority of those fatal helicopter accidents don't happen during combat. More than 80% of accidents happen because of weather conditions like dust storms, brownouts caused by sand kicked up while a helicopter is trying to land, wire strikes, engine failure, and something the military calls "controlled flight into terrain." In other words, pilots fly right into hills or mountains they aren't aware are there.
A spokesman for Sikorsky, which makes the Black Hawk, said the company wouldn't comment. Congress is not looking into Black Hawks alone -- the problem occurs across all the helicopters the military uses.
Despite what seems like chilling numbers, helicopter crashes have actually declined significantly since the Vietnam War, when 3,065 people died in helicopter crashes. That's thanks to one thing: The availability of night vision technology. In Vietnam, most surveillance missions occurred during the day, when it was easier for enemy combatants to see what they were shooting at. Today, a lot of those missions are done at night.
Operating a helicopter is possibly one of the most complex tasks a pilot can do, Blumen says. They have to fly horizontally, vertically, and make pinpoint landings in narrow, improvised spots. "There are more moving parts in a helicopter than in any other vehicle, except perhaps the Space Shuttle," he says. "It's more complex, and the potential for things to go wrong is higher. In other words, the very nature of a helicopter and the reason it is such a valuable vehicle--its ability to get in and out of tight spots without requiring a runway--makes it even more vulnerable to breakdown or shoot-down.
Nevertheless, Congress is pushing the military to cut the accident rate to .05 mishaps per 100,000 flight hours. The rate currently stands at 2.1 mishaps per 100,000 hours. The Department of Defense has to deliver a report to Congress in December outlining how it will cut the crash rate.
There are some technological fixes that could help. Terrain Avoidance Warning Systems alert pilots when they are too close to a solid object, kind of like the beeping backup warning systems that come in many cars these days. Those systems are already on a lot of helicopters that ferry VIPs around war zones, but don't work all that well for pilots on patrol or in combat. It certainly wouldn't have helped out the pilot dropping into Osama bin Laden's compound: He had to be in the treetops to get the job done.
Sikorsky, the maker of the Black Hawk helicopter, has teamed up with Honeywell and Sierra Nevada Corp. to develop technologies that can help pilots navigate even when they can't see. They've installed a "Sandblaster" system on a Black Hawk as a test project, and so far the system is getting good reviews. Sikorski is a unit of United Technologies, a technology conglomerate that also operates businesses including Otis elevators, Carrier cooling systems and Pratt and Whitney engines.
Pilots can pre-program their landing spot, and then on approach they push a button that brings the aircraft from flight to hover mode. Three-dimensional radar penetrates the sand and dust to detect the terrain and objects within the landing zone. Another program pulls the data together to create a "synthetic" picture of the landing zone.
Too many Black Hawk crashes are attributed to events other than combat. While the job of helicopters is to go in to hard-to-reach areas under all kinds of weather and environmental conditions, far too many are failing, and claiming the lives of servicemen. Congress wants to know why, and it wants the incidence of failure to be reduced.
Editor's Note: The original version of this post stated that in the movie "Black Hawk Down" the helicopter was shot down by friendly-fire. The error has been corrected.
[Image: ALI YUSSEF/AFP/Getty Images]