# Payne Stewart's plane crash
**URL:** https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303
**Category:** Factual Questions
**Created:** [July 27, 2006, 6:25pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303 "2006-07-27T18:25:03Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@Cardinal](https://boards.straightdope.com/u/Cardinal)
#### Post date: [July 27, 2006, 6:25pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/1 "2006-07-27T18:25:03Z")
Wikipedia says:
On October 25, 1999, a month after the American team rallied to win the Ryder Cup in Brookline, Massachusetts, Stewart’s life was cut short while flying in a Learjet from Orlando to Texas. National Transportation Safety Board investigators later concluded that the plane suffered a gradual loss of cabin pressure early in the flight and that all on board died of hypoxia, lack of oxygen. The plane, apparently still on autopilot, was observed by Air National Guard F-16 fighter aircraft of several states. Other than frost on the plane’s windows, the military pilots saw nothing amiss but were unable to directly observe the Learjet’s pilot or copilot, who did not respond to repeated radio calls. It is likely that the pilots and occupants already had lost consciousness. The plane continued flying until it ran out of fuel and crashed into a field near Aberdeen, South Dakota, after an uncontrolled descent.
If the plane is on autopilot, does that mean it just kept a heading and an altitude until turned off? How else can you mean to go to Texas from Florida and end up in South Dakota?
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### Author:  [@Leaffan](https://boards.straightdope.com/u/Leaffan)
#### Post date: [July 27, 2006, 6:31pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/2 "2006-07-27T18:31:54Z")
I imagine it’s basically cruise control for airplanes. It maintained the vector and altitude until it ran out of fuel.
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### Author:  [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)
#### Post date: [July 27, 2006, 6:40pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/3 "2006-07-27T18:40:34Z")
Autopilots can maneuver a plane using many different mechanisms including some very sophisticated ones. However, I am not sure how relevant that is to the answer. Jets rarely get to fly GPS direct. That is, the get routed by controllers and have to follow established airways that are like roads in the sky instead of flying straight point-to-point. If the airplane was on autopilot heading north and west at the time the depressurization occurred, a likely case is that it was set to keep flying at that heading to an assigned altitude. If you look at a map, you can easily draw a line that shows that the plane was instructed to head north before turning west and the accident occurred before the westward turn was to be made.
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### Author:  [@Duke\_of\_Rat](https://boards.straightdope.com/u/Duke_of_Rat)
#### Post date: [July 27, 2006, 6:40pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/4 "2006-07-27T18:40:53Z")
It was flying basically right up the Florida peninsula and was scheduled to make a left-hand turn. It never made the turn and flew until it ran out of fuel.
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### Author:  [@Kevbo](https://boards.straightdope.com/u/Kevbo)
#### Post date: [July 27, 2006, 6:41pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/5 "2006-07-27T18:41:34Z")
> [@Cardinal](#):
>
> If the plane is on autopilot, does that mean it just kept a heading and an altitude until turned off? How else can you mean to go to Texas from Florida and end up in South Dakota?
Pretty much, yes, autopilots hold altitude and heading.
The simplist autopilots are also known as “wing levelers” Meaning they keep the wings level, which means the heading will only change slowly. Properly trimmed, aircraft often hold altitude fairly well without pilot intervention, and are likely to climb as fuel is burned off.
This happened in '99 and the jet was probably older than that, and avionics can have long development cycles…so there it is quite likely that this aircraft did not have GPS integrated into the flight controls.
Which means the autopilot would moste likely have been using a gyroscopic compass as a reference. These can drift some, over time, so the pilot has to compare it to his magnetic compass and give it a tweak if required.
They could have been taking a less than direct route, either to avoid, or to join traffic. Air traffic controllers like to start getting landing traffic lined up in order a long way from the destination.
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### Author:  [@lieu](https://boards.straightdope.com/u/lieu)
#### Post date: [July 27, 2006, 6:41pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/6 "2006-07-27T18:41:46Z")
I’m just going by memory but if it serves correct, what first alerted Air Traffic that there was a problem is when the plane missed a scheduled left hand turn near the Florida panhandle that would vector it towards Texas.
So, (and I’m not a pilot) I’m guessin’ they either hadn’t plugged the command into autopilot yet or the autopilot was just used to control the “straight legs” of the trip, while the “turning joints” were performed manually. Again, just speculation.
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### Author:  [@Elendil\_s\_Heir](https://boards.straightdope.com/u/Elendil_s_Heir)
#### Post date: [July 27, 2006, 7:04pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/7 "2006-07-27T19:04:11Z")
I remember reading at the time that President Clinton was briefed on the situation and OK’d a shootdown if the plane strayed over populated areas. It never did, and was allowed to crash.
A sad end to a very talented golfer, and those aboard the plane with him…
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### Author:  [@dolphinboy](https://boards.straightdope.com/u/dolphinboy)
#### Post date: [July 27, 2006, 7:20pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/8 "2006-07-27T19:20:35Z")
If the same thing happeded today, assuming the most modern comparable jet with the latest avionics, would the ending be the same? Is there no way to somehow intercept the plane and guide it to a safe landing?
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### Author:  [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)
#### Post date: [July 27, 2006, 7:33pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/9 "2006-07-27T19:33:40Z")
> [@dolphinboy](#):
>
> If the same thing happeded today, assuming the most modern comparable jet with the latest avionics, would the ending be the same? Is there no way to somehow intercept the plane and guide it to a safe landing?
Jets can’t be controlled from the outside and that actually is a safety feature. I once proposed an idea here where a pilot could push a series of emergency buttons very quickly and the plane would lock the controls for good, notify ATC, and execute a safe landing at the most suitable, nearest airport. The technology is already installed in most newer airliners except for the switch and the airport choosing algorithm. People didn’t seem to like it though.
The only hope would be if the pilot had already decided to program the autopilot to fly from point-to-point before the problems. Newer autopilots can land airliners just fine and you may have even been on a flight were they did and not even have known it. They have to test the system at regular intervals to maintain its certification. Some can fly runway centerline to runway centerline although I don’t know how often pilots use it for a whole flight.
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### Author:  [@Telemark](https://boards.straightdope.com/u/Telemark)
#### Post date: [July 27, 2006, 7:35pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/10 "2006-07-27T19:35:00Z")
> [@dolphinboy](#):
>
> If the same thing happeded today, assuming the most modern comparable jet with the latest avionics, would the ending be the same? Is there no way to somehow intercept the plane and guide it to a safe landing?
Think of the terrorist safety concerns with taking over control of jet externally. I don’t think we’re likely to see that anytime soon.
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### Author:  [@Ring](https://boards.straightdope.com/u/Ring)
#### Post date: [July 27, 2006, 8:09pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/11 "2006-07-27T20:09:59Z")
Why did this happen? Don’t small private jets have oxygen mask systems? If not, I’m amazed, if so why would a slow loss of pressure cause the pilot to black out?
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### Author:  [@fortytwo](https://boards.straightdope.com/u/fortytwo)
#### Post date: [July 27, 2006, 8:11pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/12 "2006-07-27T20:11:22Z")
> [@dolphinboy](#):
>
> If the same thing happeded today, assuming the most modern comparable jet with the latest avionics, would the ending be the same? Is there no way to somehow intercept the plane and guide it to a safe landing?
There was a fatal air crash last August in Greece, involving a B737.
Although The final accident report is not published yet as far as I know, it has a similiar scenario to the Stewart accident but caused 121 deaths.
Here are a few details of the [Helios accident](http://news.bbc.co.uk/1/hi/world/europe/4542226.stm)
In this incident a pressurisation problem is assumed to have incapacitated the aircrew but there was no way that the 2 F-16 pilots could intervene to help, even if a passenger or cabin crew member was at the controls (with an oxygen mask on for instance) as was mentioned in the article.
It’s a common misconception by some folk that flying aircraft in a pc simulator would help someone fly and land an aircraft in real life.
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### Author:  [@garygnu](https://boards.straightdope.com/u/garygnu)
#### Post date: [July 27, 2006, 8:11pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/13 "2006-07-27T20:11:29Z")
Most investigators suggest that it wasn’t a slow loss of pressure.
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### Author:  [@Duke\_of\_Rat](https://boards.straightdope.com/u/Duke_of_Rat)
#### Post date: [July 27, 2006, 8:29pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/14 "2006-07-27T20:29:54Z")
Read about it from the NTSB [Here](http://www.ntsb.gov/Publictn/2000/AAB0001.htm)
> [@](#):
>
> The flight crew’s last communication with air traffic control (ATC) was at 0927:18 eastern daylight time, when the first officer acknowledged an ATC clearance to flight level (FL) 390 and the airplane was climbing through 23,200 feet.41 Her speech was normal, her phraseology was accurate and appropriate, and Safety Board testing indicated that she was not using an oxygen mask microphone for this transmission or those that she had made earlier.42 The flight crew’s failure to respond to repeated ATC radio inquiries beginning at 0933:38, when the airplane was climbing through about 36,400 feet, was the first indication of a problem on board the accident flight.
6 minutes between talking normally and not responding.
> [@](#):
>
> If the pilots had received supplemental oxygen from the airplane’s emergency oxygen system, they likely would have properly responded to the depressurization by descending the airplane to a safe altitude. Therefore, it appears that the partial pressure46 of oxygen in the cabin after the depressurization was insufficient for the flight crew to maintain consciousness and that the flight crewmembers did not receive any, or adequate, supplemental oxygen.
>
> Because this accident would not have occurred without both the loss of cabin pressure and the failure of the flight crew to receive supplemental oxygen, the Safety Board considered possible reasons for both of these key events in the accident sequence.
They had supplemental oxygen onboard, but didn’t get on it fast enough to keep from passing out.
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### Author:  [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)
#### Post date: [July 27, 2006, 8:34pm UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/15 "2006-07-27T20:34:13Z")
Because of this accident, you can’t even buy a LearJet with a sunroof anymore.
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### Author:  [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)
#### Post date: [July 28, 2006, 1:09am UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/16 "2006-07-28T01:09:53Z")
> [@Duke of Rat](#):
>
> They had supplemental oxygen onboard, but didn’t get on it fast enough to keep from passing out.
I just got through the road warrior thing (i.e., splitting lanes for 33 miles on the 405) so I haven’t looked for a link. But IIRC the O[sub]2[/sub] bottle was empty, as it had been used on a previous flight and recharging was overlooked.
Do I remember correctly?
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### Author:  [@Duke\_of\_Rat](https://boards.straightdope.com/u/Duke_of_Rat)
#### Post date: [July 28, 2006, 1:33am UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/17 "2006-07-28T01:33:01Z")
Hard to tell,
> [@](#):
>
> The oxygen bottle was dented but not breached during the impact sequence. All oxygen lines to the bottle were separated during the breakup. The oxygen bottle regulator/shutoff valve was found in the open position. The cockpit oxygen pressure gauge viewing glass was broken. The needle remained attached and read just below zero; needle slap marks were found at this reading.
> [@](#):
>
> The airplane’s maintenance records indicated that the oxygen bottle was last serviced on September 3, 1999. Between September 3 and the date of the accident flight, Sunjet Aviation operated the airplane for about 104.6 flight hours, on 90 flights. The Safety Board was unable to determine exactly how many of these flight hours were above 35,000 feet. ATC voice tapes from one of the flights indicated that the airplane was cleared to FL 370 on one leg. Although no radar data for that flight was available, the Board estimated (using ground speed and distance) that the airplane would have cruised above 35,000 feet for at least 30 to 40 minutes during that round trip itinerary. The captain of that flight told investigators that when the airplane was above 35,000 feet during that flight, he used supplemental oxygen. Board calculations indicated that this reported oxygen usage would have depleted the airplane’s oxygen supply by 14 to 25 percent, depending on which mask was used.
> [@](#):
>
> According to a Sunjet Aviation official who spoke to the accident captain before takeoff, the captain told him that the oxygen pressure gauge was noted in the green band (1550 to 1850 psi) during preflight checks on the day of the accident. According to maintenance records, the oxygen system was last serviced36 (by Sunjet Aviation) on September 3, 1999. The only written records of servicing of the oxygen system were from Sunjet Aviation;37 a survey of 15 of the fixed-base operators visited by the accident airplane between September 26 and October 20, 1999,38 revealed no charges for oxygen servicing. A flight manifest log indicates that N47BA was flown approximately 104.6 flight hours (90 cycles) between the last time the oxygen system was known to have been serviced and the accident flight. After the accident, the oxygen source used by Sunjet Aviation to service N47BA on September 3, 1999, was tested and was found to be more than 99.8 percent pure oxygen.39
> [@](#):
>
> Following the depressurization, the pilots did not receive supplemental oxygen in sufficient time and/or adequate concentration to avoid hypoxia and incapacitation. The wreckage indicated that the oxygen bottle pressure regulator/shutoff valve was open on the accident flight. Further, although one flight crew mask hose connector was found in the wreckage disconnected from its valve receptacle (the other connector was not recovered), damage to the recovered connector and both receptacles was consistent with both flight crew masks having been connected to the airplane’s oxygen supply lines at the time of impact. In addition, both flight crew mask microphones were found plugged in to their respective crew microphone jacks. Therefore, assuming the oxygen bottle contained an adequate supply of oxygen, supplemental oxygen should have been available to both pilots’ oxygen masks.
>
> The Safety Board evaluated several explanations for the flight crewmembers’ failure to receive supplemental oxygen, including an inadequate quantity of oxygen or improper servicing of the oxygen bottle and the failure (or inability) of the pilots to don their oxygen masks rapidly enough following the loss of cabin pressure.
>
> Oxygen Quantity
>
> Investigators considered the possibility that there might have been an insufficient quantity of oxygen on board the accident flight to sustain the flight crewmembers while they addressed the depressurization. The oxygen bottle was found empty. Witness marks on the cockpit oxygen pressure gauge caused by the impact were consistent with an indication of no pressure in the oxygen bottle.
>
> A Sunjet Aviation official stated to the Safety Board that the accident captain had reported that the oxygen pressure gauge was in the green zone, indicating adequate pressure of 1,550 to 1,850 psi, during preflight checks on the day of the accident. The airplane’s maintenance records indicate that the oxygen bottle was last serviced with oxygen (by Sunjet Aviation) on September 3, 1999. Between this date and the date of the accident flight, Sunjet Aviation operated the airplane for about 104.6 flight hours, on 90 flights. The Board was unable to determine exactly how many of these flight hours were above 35,000 feet,59 but ATC voice tapes from one of the flights60 indicated that the airplane was cleared to FL 370 on one leg. Although no radar data for that flight were available, the Board estimated (using ground speed and distance) that the airplane would have cruised above 35,000 feet for at least 30 to 40 minutes during that round trip flight. The captain from that flight told investigators that when the airplane was above 35,000 feet during that flight, he used supplemental oxygen. Board calculations indicated that the flight crew’s reported oxygen usage that day would have depleted the airplane’s oxygen supply by up to 14 to 25 percent, depending on which mask was used. Even though oxygen use was required on this flight (and perhaps others) and was reported to have been used, the Board is aware that pilots do not always use oxygen when required by regulation.
>
> The Safety Board contacted fixed-based operators (FBO) at 15 known destination airports visited by the accident airplane between September 26 and October 20, 1999, and none had any record of charges for oxygen servicing of the accident airplane. However, the Board cannot exclude the possibility that the airplane was serviced with oxygen after September 3, 1999, at a different airport or at no charge to Sunjet Aviation61 and that no record was made.62
>
> However, even if the oxygen bottle had been full at the beginning of the accident flight, the oxygen supply would have been completely depleted before impact because the Rogers regulator installed on one of the two flight crew masks would have automatically supplied 100 percent oxygen when the cabin altitude increased beyond 39,000 feet. This oxygen would have been released at 130 liters per minute at a pressure of approximately 0.5 psi even if the mask was not being worn by a flight crewmember, depleting a fully charged oxygen bottle in about 8 minutes. Therefore, the postimpact reading on the oxygen pressure gauge is not necessarily indicative of an inadequate predeparture oxygen supply on the accident flight.
>
> In summary, the Safety Board could not determine the quantity of oxygen that was on board the accident flight.
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### Author:  [@Broomstick](https://boards.straightdope.com/u/Broomstick)
#### Post date: [July 29, 2006, 2:23am UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/18 "2006-07-29T02:23:33Z")
We’ve had at least one prior thread on the Payne Stewart crash, but I’m having trouble finding it/them…
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### Author:  [@Tikkiw](https://boards.straightdope.com/u/Tikkiw)
#### Post date: [July 29, 2006, 3:00am UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/19 "2006-07-29T03:00:39Z")
> [@Telemark](#):
>
> Think of the terrorist safety concerns with taking over control of jet externally. I don’t think we’re likely to see that anytime soon.
A story out of Europe on building such a system:
> **[Yahoo News: Latest and Breaking News, Headlines, Live Updates, and More](http://news.yahoo.com/news?tmpl=story&cid=1509&e=10&u=%2Fafp%2F20060722%2Ftc_afp%2Fgermanyeuunrest)**
>
> The latest news and headlines from Yahoo News. Get breaking news stories and in-depth coverage with videos and photos.
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### Author:  [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)
#### Post date: [July 29, 2006, 6:09am UTC](https://boards.straightdope.com/t/payne-stewarts-plane-crash/366303/20 "2006-07-29T06:09:42Z")
> [@Kevbo](#):
>
> This happened in '99 and the jet was probably older than that, and avionics can have long development cycles…so there it is quite likely that this aircraft did not have GPS integrated into the flight controls.
>
> Which means the autopilot would moste likely have been using a gyroscopic compass as a reference. These can drift some, over time, so the pilot has to compare it to his magnetic compass and give it a tweak if required.
Depends. 1999 is pretty late for something like a Lear Jet to not have a GPS capable of being flown by the autopilot. At any rate, it would have had a slaved gyro compass or direction indicator. The gyro drift is not present as the direction indicator is slaved to magnetic north. Anything more sophisticated than a light piston engined twin would have this, most light twins have it as well.
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