Aviation Safety Corner
GREETINGS! For this month's topic, I will begin discussing, "Open-Door Debacle." The result of
door openings in flight too often is a crash. It shouldn't be that way. This is Part I of IV.
A Piper PA-23-250, en route from Las Vegas to John Wayne Airport, crashed and burned while diverting to Apple Valley, CA airport. The aircraft was destroyed, and the pilot and three passengers were killed. The pilot reported VFR on top at 8,500 feet and that she was experiencing moderate to severe turbulence. She subsequently reported that her door had come open and she was diverting to Apple Valley. A witness near the airport saw the aircraft level at about 500 feet. It then rolled abruptly to the right, and the nose dropped sharply. The aircraft appeared slightly inverted as it descended. It exploded on impact. A mechanic for the operator stated that he had repaired a broken cabin door latch spring on the aircraft, but no logbook entry could be found. As usual, the NTSB's narrative was brief and to the point.
Now, let's discuss, "Setup for Disaster." It is difficult to believe that such a simple thing as a door opening in flight has the potential to cause catastrophe, but it has resulted in some of aviation's worst disasters. This series will examine what happens when a cabin or a cargo door comes open unexpectedly in flight and what a pilot can do to cope with the situation.
Now, let's discuss, "Locks and Latches." The size, type and number of cabin and cargo doors vary widely among aircraft. How they latch and unlatch varies, as well. The cabin doors on most single-engine Cessnas have a single interior handle mounted in the armrest to lock and unlock the door from the inside. Most Pipers, on the other hand, have a two-latch system, with a handle in the side of the door and another latch on the upper door. Many Beechcraft models have a handle that must be rotated into position and locked/unlocked with a separate button. There are several other designs out there, some easier to use than others. Cargo doors can be located in the nose, in the wings, and in engine nacelles. Most of them are locked externally with a key.
The accident record shows clearly that most common reason why doors open unexpectedly in flight is because they were never closed properly in the first place.
Now, let's discuss, "Deadly Distraction." To understand why an in-flight door opening would cause an aircraft to crash, we should separate incidents involving cabin doors from those involving cargo doors.
In the overwhelming majority of incidents and accidents involving cabin doors, there is no structural compromise of the aircraft. The open door usually doesn't affect the performance or handling of the aircraft to a great extent, either. What does happen in most cases is that the pilot becomes distracted by the door, and forgets the most basic rule of aviation: No matter what else happens, fly the airplane!
Often, the pilot becomes so involved with trying to close the door that he or she loses control of the airplane. It is easy to become distracted when a door pops open in flight, because it is a very startling event, as I discovered a few years ago while taking off in a Cessna 172. The left door blew open, producing a sound like a shotgun blast. At the time, the airplane was yawed to the left, into a substantial left crosswind, and the door slammed all the way out to the stops and then back again. It finally settled in an open position about six inches from the frame. Needless to say, this got quite a bit of my attention for a few seconds. My pulse seemed to jump to about 300. I probably would have jumped right out of the airplane, if I hadn't had the belts on. But I managed not to lose control of the airplane. I tried to close the door a couple of times but found I couldn't reach it from the front with the seat in flight position. I told the tower I needed to return to the airport. After landing, I closed the door and made sure it was latched. It turned out that the latch mechanism was badly worn and that this wasn't the first time the door had opened in flight. Had I reviewed the log-books, I would have discovered this problem before flying the airplane. I might not have accepted that aircraft. At least, I would have been aware of the problem and, perhaps, less startled when the door popped open.
Now, in conclusion, remember Most General Aviation mishaps happen because pilots become distracted and quit paying attention to what their airplanes are doing.
Don't miss next month's, Aviation Safety Corner, when we'll discuss, "Cargo Door", "On the Record" and "Airline Mishaps." This will be Part II of IV.
Happy New Year!
Larry G. Harmon
FAA Aviation Safety Counselor