Learning From A Heavy-Iron Accident
Lessons gleaned from the big birds can teach us how to become safer pilots
At 5:36:20, the first officer said, “Sorry about that. I was lining up on that paper mill or something.”The captain said, “That’s all right. No problem.”
At 5:36:37, the airplane was slightly more than 2.5 nm from the airport and was transitioning from an angled base-to-final leg to line up with the runway. The Safety Board’s airplane performance study indicated that the PAPI would have been displaying one white light and three red lights when viewed from the cockpit. At 5:36:40, the PAPI display would have shown four red lights. The CVR recorded the captain stating “stable” at 5:36:49.
The first officer said, “[I’m] going to have to stay just a little bit higher. I’m going to lose the end of the runway.”
The captain said, “Yeah. Yeah. Okay.”
The performance study indicated that about this time, the airplane was 0.9 nm west of runway 9, descending through about 200 feet AGL at a vertical speed of 528 fpm and an airspeed of 146 knots. The airplane performance study indicated that the PAPI indication observed from the cockpit would have been four red lights.
At 5:37:13, the flight engineer announced that the before-landing checklist was complete. The announcement was the last crewmember statement recorded by the CVR. At 5:37:20, as the ground proximity warning system (GPWS) announced 40 feet AGL, the number-two and number-three engine power began to increase rapidly. The CVR then recorded the sound of a crunch and then the GPWS announced 30 feet AGL. The CVR recorded another crunch sound, and the number-one engine power began to increase rapidly. The GPWS announced, “Bank angle, bank angle.”
The sound of crunching and a loud squeal began; both sounds continued until the end of the recording. The airplane collided with trees in a right-wing-low, slightly nose-up attitude, then hit the ground, coming to rest on a heading of 260 degrees about 1,556 feet west-southwest of the runway. A fire broke out. The three crewmembers got out of the airplane through the captain’s sliding-cockpit window before the fire reached the cockpit.
The approach took the airplane over a protected national forest area that had no ground lights or other visible references by which the pilots could judge their height above terrain. FedEx’s recurrent training module on black-hole approaches, which the first officer received in 1999 (but was not received by the captain and flight engineer), warned that pilots who are conducting visual approaches like this often perceive the airplane to be higher than its actual altitude. Data showed that the first officer flew a concave approach with a steeper-than-normal initial descent, which is characteristic of a black-hole approach.
The Safety Board learned that the first officer’s color vision was deficient. He had been issued a medical certificate with a SODA (Statement of Demonstrated Ability) based on an eye test, which showed mild red-green color blindness. The chief of the U.S. Air Force School of Aerospace Medicine, Aerospace Ophthalmology Branch, told the NTSB that the first officer’s color-vision discrimination was impaired to the extent that would “limit him to nearly a gray-blue-yellow world. We believe that he would definitely have had problems discriminating the PAPIs, as they were designed because the red lights wouldn’t appear to be red at all, but some other wavelength that would make them more indistinguishable from white.”
The NTSB determined that the probable cause of the accident was the captain’s and first officer’s failure to establish and maintain a proper glidepath during the night visual approach to landing. Contributing to the accident was a combination of the captain’s and first officer’s fatigue, failure to adhere to company flight procedures and to monitor the approach, and the first officer’s color-vision deficiency.
Peter Katz is editor and publisher of NTSB Reporter, an independent monthly update on aircraft accident investigations and other news concerning the National Transportation Safety Board. To subscribe, write to: NTSB Reporter, Subscription Dept., P.O. Box 831, White Plains, NY 10602-0831.