Aftermath: Tipping Point

There was almost no chance that it could happen.

Aftermath Artwork

Aftermath Artwork

Both his wife and the instructor who had recommended him for his instrument rating two years earlier described the 1,500-hour pilot as thoughtful and analytical. He had "strong flying skills," the instructor said; his wife observed that "he liked to plan ahead and have a contingency plan." The 640 nm trip from Torrance, a southern suburb of Los Angeles, to Aspen, Colorado, was one he had made many times previously, occasionally diverting to Gunnison or Rifle because of weather.

He left Torrance in his Cessna T210M a little before 3 p.m. on a November afternoon. Sunset at Aspen was at 4:50 mountain time, so he would arrive in darkness. The weather was generally clear, but an airmet for moderate turbulence and icing between 8,000 msl and FL 200 was current for a cloudy area that lay generally north of his route but grazed the last 120 miles of it.

The weather gave him some concern. He had briefed with the Prescott FSS a couple of hours before takeoff and, while airborne, had contacted the FSS four times for updates. Each time, the briefer called his attention to the icing airmet. During his last conversation with Prescott, the pilot reported that he had begun to encounter snow falling from above, but that there were no clouds below him.

He had picked up VFR flight following after leaving Torrance and was talking with Denver as he veered right from Victor 8S to proceed direct to Aspen. The local time was 5:40 p.m. The Denver controller advised the pilot, who was then level at 13,500, that the minimum IFR altitude in the area ahead was 14,800.

At 6:15 p.m., the pilot asked the controller for an IFR clearance into Aspen.

"November 23B, no problem and I can get that for you; let's see here ... what altitude would you like into Aspen?"

While talking with the controller, the pilot trimmed to climb; over a space of two minutes his airspeed dropped from about 160 knots first to 140, then to 120, then to 95 knots. (The NTSB radar study from which these numbers come does not specify whether they are true airspeeds, indicated airspeeds or ­groundspeeds. While 160 knots would be an unexpectedly high indicated speed for a T210M at 13,500 feet, 95 knots would be an unexpectedly low true airspeed, corresponding to an indicated airspeed of only 77 knots.) At the same time as it began to climb, the airplane began a left turn that stabilized around standard rate.

"Well, I — we've got to go into the minimums you know for Red Table VOR. I think — what's the minimum around there, around 15,000?" the pilot asked.

"November 32B, yeah, 15,000 will be the minimum I can get you in there at, so that will work for me and so you are cleared to the Aspen Airport via direct Red Table direct, climb and maintain 15,000," the controller said.

"Cleared to Aspen airport via Red Table direct, climbing 15,000, we're 14,000 now, 6832B."

"November 6832B, thank you, and if you would get all that information you'd normally give to Flight Service, I'm going to just have you broadcast it on this frequency for the, uh, for the tapes for me."

"Sure."

"And it's awfully quiet on this frequency, so whenever you're ready you can go ahead and go for it."

"Ah, what would you like?"

"November 32B, just, uh, all that flight plan information, the color of aircraft, the fuel on board, your ETA, that kind of information for me if you can get all that."

"And I sure can; we're a Cessna 210/G, uh, VFR, we came out of, uh, Torrance, California, VFR and, uh, white aircraft with a red and blue stripe, and 14,000 now direct Red Table ... ETA right now into Aspen is about 20 minutes now ... one person on board and, uh ... and we have about one hour of fuel."

After remaining at 14,000 feet for a minute, 32B resumed climbing, still in a gradual turn. Its heading at this point was a little west of north.

"November 32B sounds good, thanks, and, uh, looks like you're doing a 360-degree turn out there; did you, uh, are you making it a long turn around towards Red Table?"

"No, we, uh, our autopilot disconnected and so we're recovering here."

At this point, according to the radar study, the airplane's angle of attack, having reached a maximum of 7 degrees, still well below the stall, diminished and its speed began to increase, but it continued to turn to the left.

"November 32B, OK, thanks, uh, if you need a heading just let me know, I can, uh, initial heading for Red Table would be about 040 heading."

"Yeah, that would be great, 32B."

Still turning left, the 210 began to lose altitude.

"November 32B, 'K, fly heading 040, when able direct Red Table, direct Aspen."

The pilot did not acknowledge. The controller called again.

"November 32B, I just want to verify your altitude, um, showing you at 13,200 ... November 6832B, Denver Center."

Two minutes later the controller, sensing trouble, relayed a request to a JetBlue flight to listen for an ELT. The bad news came back quickly: The pilots were hearing an ELT signal.

The 210 crashed in 7,650-foot terrain north of Cedaredge, Colorado. The left wing had separated late in the final dive, bending upward and aft and falling about a quarter-mile behind the main wreckage. Investigators found evidence of flutter of the left aileron, not inconsistent with a speed of over 250 knots nearly straight down. Flutter, rather than pilot-induced overstress, could have caused the wing failure.

The National Transportation Safety Board blamed the accident on spatial disorientation and "subsequent failure to maintain ... control." A contributing factor was "the pilot's diverted attention while coordinating for an instrument flight rules clearance." The unexplained "disconnection" of the autopilot was not mentioned, and there was no indication that icing had been a factor.

The NTSB considered the possibility of hypoxia. The pilot's wife said that he used an oximeter to monitor his blood oxygen saturation and had told her that he was confident of his ability to fly for extended periods at high altitude without supplemental oxygen. He had been at 13,500 for three hours before the accident. There were six oxygen bottles in the airplane; the post-crash fire made it impossible to tell whether the pilot had been using them, but there was no reason to think he had not. The NTSB noted that his radio communications had been "coherent and rational," but to me his "What would you like?" in response to a request for flight plan information suggests a pilot lagging a little behind events.

If he experienced a sudden attack of vertigo, it could have been triggered by something as slight as reaching for a map case on the back seat or rummaging in a flight bag for a blank flight plan form. An attitude indicator showing 60 degrees of bank and 60 degrees of nose-down pitch is an unfamiliar sight; severe vertigo could make it completely incomprehensible. There was little time to recover: Less than half a minute elapsed between the start of the descent and its end.

Occasionally, things can go terribly wrong even for skillful, careful and experienced pilots making familiar flights in well-equipped airplanes. How much experience the pilot had in night IFR in snow — as opposed to climbing through southern California coastal stratus — is unknown. But readiness is always important. He knew from the weather reports that he might end up flying IFR into Aspen; he should have had everything — charts, approach plates, flight plan information — ready before he ever asked the controller for a clearance. Maybe he did, but it sounds as though maybe he didn't.

_This article is based on the NTSB's report of the accident and is intended to bring the issues raised to our readers' attention. It is not intended to judge or to reach any definitive conclusions about the ability or capacity of any person, living or dead, or any aircraft or accessory. _