Into Thin Air

It was freezing with ice everywhere. Then I closed the refrigerator door and looked outside. More of the same but even colder at -1F. If flying was not an option, I could still read about flying. A series of accident reports augmented by pilot interviews and passenger statements gave the story behind each unrelated NTSB report. On the surface, incredibly bad judgment calls. A deeper dive suggested that more was at work.

First account: “It Looked Like an Airport” The 380 hour commercial pilot and her passenger suffered minor injuries when they crashed a Piper Warrior into a truck terminal parking lot during a VFR flight into IMC from Madison, WI to Bloomington, IN. The crash occurred in 2 mile vis with fog as the pilot zeroed in on strobes and “runway lights” which she saw despite the haze. The trucks appeared out of the gloom at the same time the plane ran out of fuel. The flight was at 5,500 feet for over three hours. Reduced visibility at the destination was in the flight briefing she received but the trip was flown VFR anyway.

Second account: “I had plenty of fuel on board”. The Piper Arrow ditched in a lake ¼ mile short of Orlando Executive. After a 4 ½ hour trip in a plane that (knowingly) held 4 ½ hours of fuel. All four people were able to exit the aircraft and swim to shore. They travelled at 11,000 feet for four hours. ATC supplied warnings regarding their suspected fuel state three times and suggested alternates but that would have cost the 510 hour pilot another 30 minutes.

Third account: “ They didn’t warn us about the ice” The1,280 hour pilot and four passengers were injured when their Cessna Cardinal crashed into trees and a house after accumulating an inch of ice on approach to Charleston, SC. The airspeed dropped to 75 knots by time he intercepted the localizer. They flew at 11,000 feet for 2 ½ hours to stay above a 9,000 undercast that was expected to contain rime ice. They had, in advance, received a flight station briefing with SIGMET indicating moderate icing before they departed in a plane without anti icing or deicing capability.

Note that oxygen is not required at these altitudes but NASA investigators flatly stated that two of the pilots had experienced hypoxia- a state of oxygen deficiency sufficient to impair functions of the brain and other organs. In fact, the pilot that flew at a modest 5,500 feet experienced oxygen deprivation after a half hour and that after three hours, blood oxygen levels are reported to be only 90%. All were written up as pilot error, as they should but most accidents involve a chain of events. Hypoxia contributed to bad judgment when options were available in each situation. We are left to conclude that Pilots who fly without supplemental oxygen or pressurization are at some level of risk in any cross country flight above 5,000 feet.

Mountain climbers know that pulmonary edema (which can be fatal ) occurs above 12,000 feet. The following example illustrates why higher altitudes require special consideration. It involves a clear violation of FAA regulations which state that oxygen must be used if flying more than 30 minutes at 12,500 and always above 14,000:

Fourth account: A PA-28R was destroyed when it struck terrain and burned during a forced landing attempt near La Sal, Utah. The 140-hour,noninstrument-rated pilot and three passengers were killed. VFR conditions prevailed for the flight, during which the pilot flew above 12,500 feet msl for 2 hours, above 14,000 feet msl for 1 ½ hours at approximately 16,000 feet msl for 45 minutes. The unpressurized aircraft was not equipped with a supplemental oxygen system. While flying above 14,000 feet msl, the pilot received numerous heading corrections from ATC—some of them as large as 70 degrees. At one point, the pilot reported that she was over Montrose, Colo. The controller informed her that she was actually over Telluride, about 35 nautical miles south of Montrose. As time passed, radio communication between the pilot and ATC became erratic. The airplane began to descend to more than 1,000 feet per minute with the last transmission: “Denver radio, mayday, mayday. I’ve got myself in (unintelligible).”

I thought about hypoxia after flying the Grand Canyon earlier this year. It was only a two hour flight, at 10,500 MSL. After the flight, the whole family had a slight headache. No I didn’t flathat into the canyon dodging mesas and buttes. Pilot induced turbulence was not a factor. Not that you know of anyway. Also: Don’t try the oxygen deprivation defense if you are stopped for speeding in Denver.

While I have plenty of cross country time at modest altitudes, I’ve never thought there was any risk.

Until now.