Gondola trial highlights role of cockpit IT
- By Dan Verton
- Mar 07, 1999
The high-profile trial of the Marine Corps pilot whose jet clipped a ski lift cable in the Italian Alps has ignited a debate on Capitol Hill about information technology failures in the jet's cockpit that many experts believe played a key role in the accident, which killed 20 people.
The defense of Richard Ashby, found not guilty last week, hinged on arguments that the Marine EA-6B Prowler he was flying was not equipped with a heads-up display that might have given Ashby more information about his surroundings, and that the hard-copy map he was using did not depict the gondola cable. Heads-up displays, or HUDs, provide pilots with an eye-level view of critical flight data, such as location of the horizon, altitude, heading and airspeed.
Rep. Curt Weldon (R-Pa.) told FCW last week that he plans to hold a hearing shortly after the budget authorization process this summer to investigate the technology angle, which he called "the key story" behind the gondola accident.
"I certainly believe that if [technology failure] was not the major cause, it certainly was a major contributing factor," said Weldon, who also chairs the House Subcommittee on Military Research and Development. Weldon said the hearing would "look at the technology aspects of what happened here."
Weldon's comments came only hours after a military jury Thursday acquitted Capt. Ashby, 31, of Mission Viejo, Calif., of involuntary manslaughter charges stemming from the accident. Ashby was piloting the Prowler electronic warfare aircraft at the time of the accident. Although charges were dropped against two backseat crewmen, Ashby's navigator, Capt. Joseph Schweitzer, faces a separate trial on similar charges.
The prosecution charged that Ashby flew the aircraft too low and too fast and that he recklessly ignored speed limitations set by the military. However, an expert witness for the defense testified that a common optical illusion that occurs when mountains block the earth's real horizon may have forced Ashby to focus his attention on a false horizon, thereby causing him to fly through the cables ferrying the ski lift gondola.
Paul Robinson, a longtime consultant to NASA and other agencies on commercial aviation safety issues, said the presence of a HUD would have at least eliminated the need for Ashby to look down at his map during the critical moments before his jet cut the gondola cable. "A HUD gives you a way to dispel the optical illusions with real-world data," Robinson said. "Even in marginal weather conditions, [a HUD] can give you all of the critical flight data right in front of you."
Likewise, Robert Guilford, an attorney specializing in aviation safety cases and a pilot with 35 years of flying experience, said there likely were a number of serious issues facing Ashby in the moments before the accident, given the particular type of flying he was doing.
For example, during nap-of-the-earth flying—flying characterized by very low altitudes and very common for the EA-6B and other tactical military aircraft—Ashby was likely confronted with suddenly rising terrain, Guilford said. "As the terrain fluctuates, your flight path has to fluctuate," Guilford said. "HUDs are designed so you don't have your head in the cockpit."
The Prowler has been in operation with the Navy and Marine Corps since 1971. Designed by Northrop-Grumman, the aircraft's mission is to carryout electronic warfare operations, such as intercepting, identifying and jamming enemy communications systems.
Although the military's fleet of Prowlers has gone through a number of upgrades and retrofits over the years to enhance the avionics systems, the Prowler that Ashby was flying was not equipped with a HUD. Northrop-Grumman recently won a $150 million contract to provide the aircraft with new displays and other system upgrades, but initial operating capability of the new configuration is not planned until 2004.
Experts also said that Ashby's having to lower his head to look at a hard-copy map may also have contributed to the accident. Experts point to a system developed by AlliedSignal known as the Enhanced Ground Proximity Warning System as a possible alternative to using hard-copy maps.
The AlliedSignal system is currently used in many commercial airlines and some larger military aircraft but is not specifically designed for use in high-speed tactical military aircraft, a spokesman for the company said. However, although experts agree that the technology may not have necessarily warned Ashby of the gondola cable, the system is a safety enhancement and can be customized for tactical jets.
The ground warning system can provide pilots with audio and visual warnings of terrain obstructions, preventing the need for pilots to refer to a map, said Drew Steketee, a spokesman for the Aircraft Owners and Pilots Association. Steketee also said newer systems incorporate Global Positioning Systems, advanced communications and terrain databases linked in real-time to moving color maps.
"The aspects of positional awareness are great," Steketee said. In addition, "some are pre-programmed to indicate the minimum safe altitude for your location" in real time, he said.