NTSB: Flight 3407 On Auto-Pilot, Dropped 800' in 5 Seconds

Photograph of Flight 3407 wreckage by Charles Anderson/AP

The National Transportation Safety Board revealed a number of details about the Continental Express flight to Buffalo that crashed on Thursday night.

NTSB member Steve Chealander said the plane was on autopilot during part of its descent. Chealander told the AP that "the company that operated the flight recommends pilots fly manually in icy condition" and that pilots are required to be in manual in severe icy weather. He said, "You may be able in a manual mode to sense something sooner than the autopilot can sense it." This will raise more questions about the FAA's regulations over flying conditions in icy weather—the Buffalo News reports that other turboprop carriers suspend their flights during cold weather.

The NTSB also described the plane's violent final moments, saying it dropped 800 feet in five second. From the NY Times:

Closer examination of the cockpit voice recorder and the flight data recorder from the plane shows that 26 seconds before the recordings were stopped by the impact, a warning alerted the crew that the plane might lose lift and fall out of the sky. An automatic system tried to push the nose down to gain airspeed, and yet the nose climbed to 31 degrees, far steeper than the steepest normal climb. Suddenly, the nose plunged to a down angle of 45 degrees, almost like a fighter plane breaking off to dive. Then it rolled right, beyond 90 degrees, all the way to 106 degrees.

On Saturday, Chealander had said that the planedid not nosedive into the house in Clarence Center: "What we found were all four corners of the airplane -- the cockpit, the tail section, both wings and engines -- and they're where they should be if the plane was laying flat."

Contact the author of this article or email tips@gothamist.com with further questions, comments or tips.

By Jen Chung in News on February 16, 2009 1:49 AM

Comments [rss]

sharpshoota

Auto pilot is for wusses.

sj

jzny, great video as it really helped me, a non-pilot, understand the kind of things that can precipitate a tail stall. Probably one of the more chilling moments of the video is when the NASA test pilots doing the research did in fact encounter a tail stall. I was able to see really how fast it developed. I can imagine how difficult that would be to diagnose and recover from when they are low and slow on approach.

I'll be interested to see what the full NTSB investigation shows.

jzny

http://video.google.com/videoplay?docid=2238323060735779946

This is the video on tailplane icing.

jzny

Yesterday, as the evidence of what happened in the Buffalo crash started to emerge, a number of professional pilots mentioned a NASA test video they watched as part of their transition training for the ATR. It is a perfect fit - with pictures - to the facts that have so far been reported on this accident. The critical point is that a tailplane stall due to icing can be quite difficult to distinguish from a normal wing stall, but the actions necessary to recover are the exact opposite - - pull back on the yoke and reduce power.

You can see it all here

Interesting that while several people mentioned having seen this during ATR training, none of the many Dash-8 pilots discussing the accident mentioned seeing it during their transition to that type. ATR (and Embraer) have had icing-related accidents. the Dash 8 had not (until friday.)

Seriously, it's a very sobering video. If the Buffalo plane did indeed suffer a tailplane stall when they extended flaps, very, very few pilots would have been able to diagnose it and recover in time.

mzungu

this is all very Airframe by michael crichton. what those people must have experienced. horrible.

FelixtheCat & Christine Quinn'

http://www.planecrashinfo.com/cause.htm

Mechanical Failure second to Pilot error are the causes of fatal accidents..

Chealander said the plane was on autopilot until the "stick shaker" and "stick pusher" kicked in, automatically putting the plane back in the pilot's hands."

Tragic. R.I.P.

jaycjay

Basically, while I'm not going to get much into this on Gothamist where most comments will be from people who know little about the issues, I wouldn't draw many conclusions from mainstream media stories on this especially so early in the investigation. There've already been things stated as fact in early stories that have since been disproven. Hey, yesterday they were stating with certainty that it hit nose first, remember?

Here's a quick example just from the few sentences posted here of a writer knowing little about aircraft flight: "Suddenly, the nose plunged to a down angle of 45 degrees, almost like a fighter plane breaking off to dive."

Nope, not at all like that. A fighter plane will over to dive, using the "lift" force reversed to go down. Simply lowering the nose would result in a much too gradual change in attitude.

Just in a quick read through the linked article I can find a few other misstatements or misinterpretations.

Anyone who wants to skip past all the uneducated speculation might want to try a site like pprune.org or others where actual professional commercial pilots gather, and avoid the journalists who yesterday were covering some completely different topic and today have to pass themselves off as aviation experts.

Mostly what you'll get from the pros is advice not to make any judgements until the investigation is complete. Of course the journos have their deadlines and news cycles, so any speculation, statement, or guess will be reported breathlessly -- until some other event takes them on some other hunt.

NannyState

It's looking more and more like pilot error. They left it on autopilot during a severe event? What were they doing in there? Praying to Jesus?

longacre

Sounds odd, but the NTSB guy actually said this isn't necessarily abnormal. "You're encouraged to use the autopilot to help you with the workloads of these high intense weather situations that we fly into all the time," he said. "To say that they should not have been flying on autopilot is not correct."