The Fine Art Of Crashing

For better or worse, I'm usually riding in the back of the bus, which means I board early and depart last, but I've always been convinced the rear of an airliner is the safest place to fly, even if there is more noise and vibration back there.

For that reason, I was especially interested in a two-hour Discovery Channel program that aired on October 7 titled "Plane Crash," part of Discovery's Curiosity series. It was an investigation by a group of scientists who spent four years and $4 million to study crash survivability by flying an airliner into the ground under controlled conditions.

They purchased a well-used Boeing 727, rigged it with G sensors and two-dozen cameras; a trio of $150,000 anthropomorphic crash-test dummies; a dozen low-tech dummies and a model airplane remote-control system.

Then, they hired an airline crew to fly the jet toward a smooth section of remote desert south of Mexicali, Mexico, and bail out after transferring radio control to a Cessna 337 flying in tight formation. The Boeing's convenient aft airstairs were exactly the reason the 727 was chosen for the mission. (You may recall the 1971 hijacking by D.B. Cooper of a Northwest Airlines 727 in 1971. Cooper extorted $200,000 from Northwest and bailed out over Oregon the same way.)

The Skymaster maintained close formation and guided the 727 to a fairly flat but spectacular impact with a vertical speed of about 1,500 fpm. Thirty-eight cameras chronicled the event from every possible angle, both inside and outside the Boeing.

Such a feat had never been done before, at least not successfully. A joint NASA/FAA team tried the same trick in California's high desert back in 1984 with a radio-controlled Boeing 720. That test was intended, among other things, to determine if an experimental, anti-misting kerosene fuel would resist ignition.

It didn't. The test went wrong at the last minute---the left wing dropped to the desert prematurely, the airplane came apart on touchdown and the special fuel created a huge fireball.

This new experiment was done on a far less extravagant scale, but it nevertheless required a team of 300 people---security, fire rescue, scientists, TV executives, cameramen, pilots, government officials and hangers-on. Everyone knew there was no possibility of recovering the aircraft once Captain Jim Bob Slocum bailed out the back door.

Unlike the 1984 crash, where the main point was to see if the experimental fuel would ignite, it was imperative that this airplane NOT burn as a result of the crash, lest all the scientific data be lost. That's a neat trick with a 120-ton airliner if you can pull it off.

They did. Slocum and his flight crew headed for a 3,000-foot-long patch of desert laid out in the shape of a makeshift runway. They configured the airplane for landing with gear and flaps down, and established a consistent descent at 135 knots. At 3,500 feet AGL, the captain turned control over to the Skymaster crew flying in loose formation. Then he exited through the rear door, and the 727, nicknamed Big Flo by Captain Slocum, was on her own.

(The aircraft was also rigged with a fail-safe device dubbed "Deep Six," designed to control pitch only. If the standard radio-control system failed, Deep Six would dive the 727 steeply into the desert floor.)

The result was fascinating television, especially for airplane buffs and those interested in the science of crash investigation. It also didn't hurt that something would be totally destroyed in front of anyone with a picture box.

The aircraft crashed slightly nose down, and the nose gear immediately dug in and caused the entire cockpit to break away and fold under the fuselage. Both main gear snapped off exactly as they were designed to do, absorbing some of the impact. Later, it was determined that anyone remaining in the crew compartment wouldn't have survived, and that most passengers forward of row seven also would have suffered fatal injuries.

Big Flo skidded pretty much straight ahead, but finally came to a stop in three pieces. The radio-control system in the Skymaster had brought all three engines to idle before touchdown, but the force of impact sent the center engine back to full power, raising a huge cloud of dust. Firefighters poured a stream of water into the intake and eventually drowned the turbine to a stop.

When the dust had settled and the fire risk was deemed unlikely, the scientists went aboard and began to investigate the results. Against all odds, all 32 channels of streaming data had worked perfectly, providing much of what the scientists were seeking.

One of the first discoveries was that, while most of the fuselage was intact, the impact had deconstructed the roof panels and caused wiring and cables to fall down into the cabin. That would have represented a significant hazard in trying to exit the aircraft.

Two of the "smart" dummies had been installed in successive rows, one pre-positioned in the recommended airline brace attitude---leaning forward as far as possible---and the other sitting upright.

To no one's surprise, the dummy in the braced position fared better, sustaining some theoretical injuries, but nothing major. The upright subject was deemed to have suffered significant back and head damage, the latter from slamming into the seat in front of it.

The onboard cameras suggested a second benefit of the brace position was better protection from flying debris. The unbraced dummy was hit by several pieces of the interior as portions of the aircraft disintegrated during the runout.

Another conclusion was the real benefit of sitting in close proximity to an emergency exit. The science team analyzed the difficulty of extracting dummies through the emergency exits and concluded the best seating position for safety is within five rows of any exit. Otherwise, debris, wiring and unconscious passengers could make egress difficult or impossible.

An important result was what most would have predicted after seeing news coverage of the aftermath of airline accidents. Since the majority of accidents involve uncontrolled contact with the ground in a nose-down attitude, the greatest damage occurs in the front of the aircraft, and the least damage in the rear. This simulated accident was closer to a controlled, straight-and-level emergency landing; yet, because the nose gear didn't break away, it was apparent the flight crew would have been critically injured.

The G-distribution throughout the fuselage was also consistent with that conclusion. The forward-third of the cabin sustained dangerous loads averaging about 12 Gs, while deceleration in the middle section over the wing dropped to more like 8 Gs. Crash loads in the far rear of the passenger cabin were recorded at 6 Gs, normally a survivable level.

What does this mean for passengers? MIT studied airline safety between 2000 and 2007, and concluded the odds of dying in a crash are about one in 14 million. If you trust statistics, that means a passenger who flies one flight a day would need 38,000 years before being at risk.

For general aviation pilots, the takeaway is that crash landings in any aircraft often ARE survivable, contrary to popular belief. There's nothing ghoulish or fatalistic about studying plane crashes, even airline accidents. When you need information, the more the better.

Most of us don't fly Boeings (except for a few Stearman owners), we don't always have convenient, pancake-flat desert below and we can't choose to sit in the last row of seats, but if you're smart enough to touch down straight and level at minimum speed, you have a good chance of walking away.