Plane & Pilot
Tuesday, April 7, 2009

More Than Monitoring

Glass cockpits ease workload, but pilots shouldn’t forget to maintain their flying proficiency

ntsbWhile I was at an FBO at the Westchester County Airport north of New York City a couple of days ago, a guy I hadn’t seen in a long time walked in. We immediately started catching up on a host of things, not the least of which were the predictable topics of what we’re flying and how much (or little) we’re getting in the air these days.
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A few minutes later, in stable level flight, it was time to turn on the autopilot for a test. The equipment was taking us to the first waypoint and the course was holding steady. Then, the aircraft’s nose started to rise. The nose-up attitude increased sharply, and we were climbing fast. The pilot attempted to troubleshoot, but the controller was on the radio within seconds, asking what we were doing at 3,900 feet. The pilot replied that there was an autopilot problem; the controller said it didn’t matter because there was no immediate inbound traffic. The pilot asked for vectors to return for landing. On the way back in, the autopilot didn’t do any better, so the pilot flew the approach by hand. Back to the shop.

This started me wondering whether the NTSB’s accident files might shed any light on the extent to which pilots of advanced aircraft have been getting into trouble because of inadequate training or equipment malfunction. A search revealed that there weren’t enough accidents in which glass-cockpit equipment was prominently mentioned to detect any patterns. But there was enough anecdotal evidence to suggest that all pilots who operate in glass cockpits need to be as studious and cautious as my friend.

A student pilot was seriously injured and his instructor received minor injuries when the Cessna 172S they were flying struck trees on a mountain near Asheville, N.C. The night/VFR flight originated from Big Sandy Regional Airport in Prestonburg, Ky. The instructor reported that the student was flying the airplane. They had received the weather on a computer before departure and planned a direct flight to Thomson-McDuffie Regional Airport in Thomson, Ga.

After departure, they climbed to 7,500 feet MSL and stayed there for about an hour, using the airplane’s GPS and MFD for navigation. The instructor said the ceiling began to drop and they had to descend to remain clear of clouds. They went down to 4,000 feet, checking the moving-map display at least three times to determine the lowest altitude they could be at while maintaining adequate terrain clearance. Both the instructor and the student reported that the highest terrain shown was between 2,000 and 3,000 feet MSL. The moving-map display was set at a range of 40 nm. According to the instructor, as they descended to 3,500 feet, the airplane began hitting the tops of trees. The instructor said the airplane was in no more than a five-degree nose-down attitude. It was on the ground quickly and came to a sudden stop. The two waited until daylight before seeking help.

Representatives of the NTSB, FAA and aircraft, engine and avionics manufacturers examined the GPS and MFD at a facility in Griffin, Ga. The data cards in the units were found to be current. The NTSB report contained nothing to back up the claims of the student and instructor that the GPS and MFD didn’t give them accurate readings of the terrain elevation. The NTSB noted that a bold-type warning in the MFD’s guide states, “Never use the terrain displayed on this equipment as your sole reference for terrain avoidance.”

The NTSB determined that the probable cause of this accident was the instructor’s inadequate visual lookout and failure to remain clear of objects during flight.

A Cessna 182T owned and operated by the Civil Air Patrol (CAP) crashed during climb to cruise altitude about 13 nm southwest of Las Vegas, Nev. Night/VFR conditions prevailed. Both persons onboard were killed. The airplane, which was equipped with an integrated cockpit system incorporating a PFD and an MFD, had taken off from North Las Vegas Airport and was headed for Rosamond, Calif.


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