Breaking news and opinions from MousePlanet writer, editor and podcaster Mark Goldhaber.
NTSB: Driver of Monorail Purple tried to avoid crash
Posted 07-08-2009 at 06:25 PM by Mark Goldhaber
Austin Wuennenberg, the monorail operator killed in Sunday morning's accident, may have helped to keep the passengers on Monorail Purple from injury.
The National Transportation Safety Board released a "factual information" media advisory today related to its investigation into the collision. The facts appear to be very similar to those that were reported in Monday's Walt Disney World Update and Tuesday's MouseStation Podcast.
Here's a map to let you follow along. Satellite image is © Google.
Monorail Pink emptied its train and went past the switch between the Epcot loop and a spur track that led to the Magic Kingdom loop to transfer on its way back to the barn. Monorail Purple pulled into the station and loaded a family of six. The pilot of Monorail Pink was told to back through the Epcot/spur switch, along the spur track, through the spur/Magic Kingdom loop switch and on through the Magic Kingdom loop, but the Epcot/spur switch had not moved to connect to the spur track. Pink backed along the Epcot beam into Purple. The one piece of information that we did not have was that Monorail Purple had actually been given clearance to leave the station and was moving forward out of the station as Pink came at it at 15 mph.
According to the NTSB advisory, "There are indications that the operator of the Purple train had brought the train to a stop and had attempted to put the train in reverse prior to the collision. To this point in the investigation, no anomalies or malfunctions have been found with the automatic train stop system or with any mechanical components of the switch or with either of the trains."
What this means is that Wuennenberg, seeing Monorail Pink suddenly rushing toward him, had the presence of mind to stop the monorail train and try to back it out of Pink's way. Unfortunately, there was not enough time and Pink plowed into Purple, killing Wuennenberg. If Purple had continued accelerating forward, the combined speed of the trains at the moment of impact would likely have been 30 mph, the maximum combined speed of two monorails traveling in override mode. (As discussed in the WDW Update, Sunday's blog post and the MouseStation Podcast, the monorails needed to be in override mode both to go through the switch and to get into the station while another monorail was at the switch.) If the monorail was stopped, the impact would have been 15 mph, and if Wuennenberg had been able to get it at least started into reverse, the impact speed may have been as little at 10 or even 5 mph. The resulting decrease in impact speed most likely prevented the family aboard Purple from sustaining serious injury.
A couple of questions come to mind, though.
1) The NTSB found that "To this point in the investigation, no anomalies or malfunctions have been found ... with any mechanical components of the switch or with either of the trains." This means that the switch was functioning properly, and that it was likely entirely a communication error. Somehow, Monorail Pink was given the go-ahead without the track switch engaging to the spur track. Did the monorail shop give clearance without moving the switch? Was only the Magic Kingdom/spur switch engaged, while the Epcot/spur switch was never triggered? Did the monorail control center mishear something from the monorail shop and give clearance without the monorail shop having said that it was OK to do so? How did Monorail Pink get the clearance to back through the switch when it had not engaged?
2) The Epcot/spur switch is fairly close to the TTC. If Monorail Purple had been given the go-ahead to pull out of the station, while Monorail Pink was just coming through the switch, isn't that cutting it a little close? With the low volume of traffic at 2 a.m., couldn't they have waited a little longer to release Purple to move forward? What was the reason for the tight interval?
3) While the monorails were not expected to sustain any impacts (as illustrated by the fact that there were no major crashes in the prior 38 years), how could a collision at a speed of no more than 15 mph cause so much damage?
There are many more questions to be asked and answered, though it is likely that we won't get any more answers until the NTSB releases them. We'll stay on top of this story and continue to post updates as we get further information.
The National Transportation Safety Board released a "factual information" media advisory today related to its investigation into the collision. The facts appear to be very similar to those that were reported in Monday's Walt Disney World Update and Tuesday's MouseStation Podcast.
Here's a map to let you follow along. Satellite image is © Google.
Monorail Pink emptied its train and went past the switch between the Epcot loop and a spur track that led to the Magic Kingdom loop to transfer on its way back to the barn. Monorail Purple pulled into the station and loaded a family of six. The pilot of Monorail Pink was told to back through the Epcot/spur switch, along the spur track, through the spur/Magic Kingdom loop switch and on through the Magic Kingdom loop, but the Epcot/spur switch had not moved to connect to the spur track. Pink backed along the Epcot beam into Purple. The one piece of information that we did not have was that Monorail Purple had actually been given clearance to leave the station and was moving forward out of the station as Pink came at it at 15 mph.
According to the NTSB advisory, "There are indications that the operator of the Purple train had brought the train to a stop and had attempted to put the train in reverse prior to the collision. To this point in the investigation, no anomalies or malfunctions have been found with the automatic train stop system or with any mechanical components of the switch or with either of the trains."
What this means is that Wuennenberg, seeing Monorail Pink suddenly rushing toward him, had the presence of mind to stop the monorail train and try to back it out of Pink's way. Unfortunately, there was not enough time and Pink plowed into Purple, killing Wuennenberg. If Purple had continued accelerating forward, the combined speed of the trains at the moment of impact would likely have been 30 mph, the maximum combined speed of two monorails traveling in override mode. (As discussed in the WDW Update, Sunday's blog post and the MouseStation Podcast, the monorails needed to be in override mode both to go through the switch and to get into the station while another monorail was at the switch.) If the monorail was stopped, the impact would have been 15 mph, and if Wuennenberg had been able to get it at least started into reverse, the impact speed may have been as little at 10 or even 5 mph. The resulting decrease in impact speed most likely prevented the family aboard Purple from sustaining serious injury.
A couple of questions come to mind, though.
1) The NTSB found that "To this point in the investigation, no anomalies or malfunctions have been found ... with any mechanical components of the switch or with either of the trains." This means that the switch was functioning properly, and that it was likely entirely a communication error. Somehow, Monorail Pink was given the go-ahead without the track switch engaging to the spur track. Did the monorail shop give clearance without moving the switch? Was only the Magic Kingdom/spur switch engaged, while the Epcot/spur switch was never triggered? Did the monorail control center mishear something from the monorail shop and give clearance without the monorail shop having said that it was OK to do so? How did Monorail Pink get the clearance to back through the switch when it had not engaged?
2) The Epcot/spur switch is fairly close to the TTC. If Monorail Purple had been given the go-ahead to pull out of the station, while Monorail Pink was just coming through the switch, isn't that cutting it a little close? With the low volume of traffic at 2 a.m., couldn't they have waited a little longer to release Purple to move forward? What was the reason for the tight interval?
3) While the monorails were not expected to sustain any impacts (as illustrated by the fact that there were no major crashes in the prior 38 years), how could a collision at a speed of no more than 15 mph cause so much damage?
There are many more questions to be asked and answered, though it is likely that we won't get any more answers until the NTSB releases them. We'll stay on top of this story and continue to post updates as we get further information.
Total Comments 9
Comments
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3) Speed is not the problem. It is inertia. A heavy object powered by an electric motor will continue to move until current is removed. I would guess that pilot of Pink did not stop the motor until a short time after the collision.Posted 07-08-2009 at 06:46 PM by steven 
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Thanks, Steven! I had a feeling (and was hoping) that I missed something somewhere. So basically, after they hit, the motors kept driving Pink through Purple until they were shut down.
Each monorail has eight DC motors rated 113 HP each, which means that it was 904 HP pushing the train.
The monorail fact sheet says that "Train bodies are made of a high-strength composite honeycomb material that allows high strength at a low weight." I guess even high-strength composite honeycomb material has its limits.Posted 07-08-2009 at 07:38 PM by Mark Goldhaber
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2) Mark, I think NSTB's presumption (or our misreading of their release) that Purple came to a sudden stop and then hit reverse is in error. I can't see Purple, knowing his anti-collision system is off and that a train is being diverted just ahead of him, would begin pulling out of the station. This is ludicrous. Purple was almost certainly at a standstill when he noticed Pink coming in at him and quickly hit reverse; it just didn't pick up speed in time.
3) For whatever reason, the Monorails have always had shells that, upon impact, "crumple like Reynold's Wrap," according to their original designer. There have been three or four other collisions over the years, all at modest speeds, and all caused considerable damage.Posted 07-08-2009 at 07:41 PM by David Koenig
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David, perhaps he had it in gear but wasn't moving forward yet?
Of course, if they were trying to shrink turnaround times and made it SOP for the train in the station to start moving as soon as the other train cleared the switch, it's possible that he was told to go ahead and he did so. We'll have to wait for the NTSB report to know for sure.Posted 07-08-2009 at 08:06 PM by Mark Goldhaber
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Surveillance video would reveal if Purple was in motion. Other than that, they have switch and control settings in the cockpit, and possibly skid marks on the beam way for them to draw this conclusion.
Now, if Purple was stopped on the track (brakes set), Pink would have stopped suddenly after it came in contact with the bulkhead of Purple. This would cause the electric motors to stall tripping the breakers.Posted 07-08-2009 at 08:34 PM by steven
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it seems in the description of the report facts in the Orlando Centinal that Purple was not pulling out of the station - but indeed had pulled in to drop off it's passengers at the station and was stationary. This is in contrast to mark's discussions (and others) that the collission happened just past the station as it was pulling out - and instead was inside the station. I had read somewhere that the picture of the trains outside of the station (but still collided) was when they backed it out more in order to allow the driver of Pink to exit his train. Hmmm...Posted 07-08-2009 at 11:23 PM by olegc
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As an old war horse (retired veteran) I was assigned at one point in my career to a combat crew. Anything you had to back up 2 1/2 ton, 5 ton and numerous other vehicles of shapes and sizes, you were required to have a spotter. So ever since hearing of this accident I keep wondering "Why oh why was no one watching out for Pink that it had made the switch or not".
Posted 07-09-2009 at 09:05 AM by DwarfPlanet
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I only have questions at this time so I can be of no help for answers. I have loved the Disney Universe for years and I find it extremely heartbreaking that this young man died while "on stage"
1) In the AP photo posted on CNN.com, it shows the two trains together outside the southwest side to TTC looking southeast to the bus pick up area. The photo is consistent with reports, Monorail Pink passing back through the station and Monorail Purple arriving. I am confused because the guest video shows the accident in the station with people yelling into the Monorail Purple. Where did the accident actually occur and how did AP get a photo outside the station going the opposite direction of the Spur Switch?
2) I've always assumed the switch process was A. forward to Epcot then stop and wait for Spur switch, B. Back to TTC Magic Kingdom Line and stop and wait for Spur switch, C. Forward to Garage Spur switch. Why would Monorail Pink driver need to pass all the way through the station? When in reverse the driver should have known the switch was missed because the Spur would have been outside the left window.
3) What about radio traffic?
This story makes me very sad and I've heard rumors that they were understaffed that night. I hope to find out that Mr. Wuennenberg chose to stay inside Monorail Purple in a attempt to protect the passengers instead of being stuck 30 ft in the air with no exit, waiting for the impact.Posted 07-11-2009 at 08:40 PM by hoffman24
Updated 07-12-2009 at 07:53 PM by hoffman24 (Changed Ticket and Transportation Center acronym.) -
Point of clarification on the guests:
They were most likely getting on Purple for a trip to Epcot, as purple was on the Epcot line. Epcot had closed at 10PM. The Magic Kingdom closed at 1AM. The only reason that the Epcot monorail was running was to take passengers from the Magic Kingdom back to the Epcot parking lot. These guests most likely park hopped from Epcot, or parked there if the TTC lot was full when they arrived. So, they had probably just boarded Purple at the TTC.Posted 07-12-2009 at 05:27 PM by coasterfanboy
