NTSB Says a Downdraft Killed Steve Fossett 101
jd writes "The National Transportation Safety Board has now released the text of its examination (full narrative available) into the crash of Steve Fossett's aircraft on Sept 3rd, 2007. It concludes that downdrafts were the likely cause of the crash, dragging the plane into the mountain with such force that, even at full power, it would have been impossible to escape the collision. Pilots experienced in the area report that those winds can rip the wings off aircraft; and Mark Twain remarked that they could roll up a tin house 'like sheet music.' One must wonder why such a skilled aviator was taking a gamble with such hostile conditions, given that he was looking for a flat stretch of land to race cars on, but that is one mystery we shall probably never know the answer to."
Mountain Wave Action (Score:5, Informative)
The proper term for what they're describing is a mountain wave or wave action. http://en.wikipedia.org/wiki/Lee_wave [wikipedia.org] contains a good description of the effect.
Mountain waves can be felt in small piston powered aircraft even flying significantly above the tops of the mountains, even several thousand feet above the peaks on either side of the valley you're crossing.
If you're holding altitude, you see that you speed up when you're crossing falling terrain and slow down when you're crossing rising terrain -- because as you cross the rising terrain, you're in the downdraft and so to maintain altitude, your airplane "feels" like it has to climb to stay at the same altitude in the falling air. Climbing requires additional power over simple cruise flight, or you slow down.
I've seen airspeed of an aircraft that should cruise at 150 knots, range from 90-180 knots, depending on whether you're on the uphill or downhill side of the wave. In severe conditions, you just cant' maintain altitude without slowing down too much, and you have to vary altitude to ride the waves.
It can be a scary experience knowing you don't have enough power to out-climb the wave -- That's the reason that you typically fly significantly higher in the mountains, even with good visibility -- You're not worried about hitting the mountains because you can't see them, you're worried about getting sucked by these waves and not having enough altitude to ride them out.
Re:Can a Slashdot pilot tell us . . . (Score:2, Informative)
Re:Can a Slashdot pilot tell us . . . (Score:3, Informative)
Any pilot can call for a weather briefing prior to a flight, but most don't. For most private traffic, the pilot never talks to anyone other than the other pilots in the area advising what they are up to... and technically don't have to do that even if the airport doesn't have a control tower (most don't).
It is extremely unlikely that the weather briefer or ATC would inform pilots of mountain phenomena because it's like warning pilots that bright blue light shines from every possible direction when not obscured by clouds. It's just a given.
There are basics about mountain flying you are taught regardless of where you learn, and any west coast pilot has to deal with these realities if they go anywhere inside of the coast. I've fought off 400 ft/min downdrafts on flat land 800 miles from a mountain.
Fossett would have known very well about mountain waves. He would not have continued towards the peak of the mountain if he was sinking. The probable cause report doesn't really inform us of anything more valuable than "the sky is blue".
Re:Can a Slashdot pilot tell us . . . (Score:1, Informative)
If your flying "general aviation" (private flying, non-commercial), then the answer is no. Once your in the air, the ATC doesn't talk with you. General Aviation does its own thing once their airborne. General Aviation pilots just have to stay out of restricted airspace that is used for commerical, controlled-by-ATC flights.
This is so wrong in so many ways...
First, GA (general aviation) is just about everything not "airline". Corporate jets, private jets, crop dusters, all the way down to home-built experimental airplanes. It's not just "private flying" or "noncommercial".
Second, GA doesn't have to stay out of "commercial controlled-by-ATC airspace". GA uses the same airspace as everyone else. There is airspace where you MUST have an ATC clearance ("controlled by ATC"), but there is no distinction between GA and other users who can go there once you have that clearance. Most of the airspace in the country, especially in the western part, doesn't require ATC clearance unless you are flying IFR (instrument flight rules) and in IFR conditions ("the clouds").
Third, "restricted" airspace is a defined classification of airspace. It is defined as "airspace that contains some hazard, usually unseen, that creates a danger to flight". It is NOT prohibited to fly there for either GA or nonGA flights. This airspace is clearly marked on every sectional (aviation map). Again, there is no distinction between GA and nonGA flights in this airspace. The only relevance to "controlled by ATC" is that ATC will coordinate flights that it clears through restricted airspace with the controlling agency on behalf of the pilot.
And finally, ANY GA flight is capable of requesting "flight following", which is "communication with ATC", but not control. (If ATC is too busy, they can turn the request down.) That means ANY GA flight can be talking to ATC, and yes, if time permits, ATC will inform those GA flights is it voluntarily communicating with of any known problems.
As to filing a flight path, I'm not sure whether General Aviation has to do that or not, but I am pretty sure the FAA wouldn't give them a warning based on what they filed. It's up to the pilots to make sure the area they are going to be flying in is safe, not anyone else.
Nobody files a "flight path", they file a "flight plan". If you are flying VFR (visual rules) within the borders of the US, it is not mandatory, but it is highly recommended for any flights away from your home airport. If you are flying IFR, you MUST file a flight plan (even if it isjust an "abbreviated one") and have an ATC clearance prior to entering IFR conditions. The only distinction related to GA vs nonGA flights in this matter is that airlines are REQUIRED to file IFR flight plans for all flights, and GA is only required to file IFR for flights in IFR conditions.
One of the requirements for making a flight is knowledge of the weather conditions, usually met by getting a weather briefing. That weather briefing is supposed to include warnings about all kinds of things, weather related (AIRMETs, SIGMETs) and otherwise (NOTAMs). It also includes "winds aloft", which combined with knowledge that you are flying in mountainous terrain, tells you to expect up and down drafts and which side of the mountain will have which. Since the FAA doesn't provide the weather briefings, no, the FAA won't give you warnings based on what you filed, but you get them in other ways.
The only thing you got right is the last sentence: it is ALWAYS the pilot's responsibility to know about the area they are flying in, and the FAR (flight regulations) make this clear. Why Steve was flying near a mountain is anybodies guess, but it is not an inherently unsafe thing to do, and even the safest things to do sometimes result in crashes.
Re:Insulting summary (Score:5, Informative)
To someone who isn't an experienced pilot, it isn't obvious. But you should know that it is a significant part of the training for all private pilots.
I've been licensed for more than 20 years as a private pilot. I've taken mountain flying instruction. I've flown around and over the Rocky Mountains. This hazard is a simple issue of flight planning.
I know exactly what performance my aircraft is capable of, as should every pilot who sits in the left seat. I read reports of the winds aloft. I set personal minimums for what I'm willing to fly in. I know, for example, that if the winds aloft at 3000' are approaching 30 knots, that I can expect significant turbulence and down-drafts from the Appalachian mountain chain for up to 100 miles East. I might fly in those conditions if I'm going Eastward. However, if the winds aloft are 35 knots or greater at 3000, I know I'm staying on the ground.
It's not that I can't handle those situations; I can and I have. My goal is to have a reserve in case the forecast is wrong. I've seen blown forecasts more times than I care to think about.
Steve Fossett had a momentary lapse of judgment. It happens to the best of us. Every year, people crash while flying around mountains and canyons from exactly the same damned thing that bit him. There is little room for error when flying in the mountains. Each flight should include a careful evaluation of local and regional weather conditions, terrain, and aircraft performance. Yeah, there are people who launch in to the blue without checking this stuff. Most of the time, they survive without incident.
Those who don't do adequate flight planning in this terrain are accidents waiting to happen.
Re:One must wonder ... (Score:5, Informative)
In searching for Fossett, they found numerous unreported or otherwise undocumented crashed planes. More than likely, any aviator who said that they "knew" it could happen were witnesses to another plane crashing, helped with the search and rescue of a fellow aviator, or simply accounted for the forces and the strength of small aircraft.
I had discussed this with some people who are very experienced aviators, and they all came to the same conclusion. It was most likely wind that brought him down. The second guess would be a mechanical failure and attempted crash landing. They ranked the second one way behind the first.
If I read the NTSB review correctly, his altimeter was reading above the mountain peaks, but adjusted for current temp and pressure that would put him a bit lower than them, which should have been ok. They lost radar contact with him approx 1km from the crash site. In that time, he went about 1km (obviously) and a dropped a few thousand feet.
The report does state that the entire plane was present at the accident site. Well, except for the burnt off parts. They indicate the wingtip lights were present, which would imply the wing came down with the plane. If they had broken off, they would have likely been found at a different location.
I'm sure he did everything he could. Sometimes that's just not enough, even for people who are really good. :(