Unhappiest Place on Earth: The 2009 Walt Disney World Resort Monorail Collision

Max S
13 min readMar 28, 2021



The Walt Disney World Resort is an entertainment complex in Florida consisting of four theme parks, two water parks, 27 themed resort hotels, 9 non-Disney hotels, several golf courses and a camping resort, among other venues. Opened in October 1971 the centerpiece of the Resort is the “Magic Kingdom” theme Park with its famous Cinderella Castle. The Resort’s “Transportation and Ticket Center”, the main traffic hub and also site of this accident, is located centralized in the resort, 23.5km/14.6mi southwest of Orlando and 99km/61.5mi northeast of Tampa.

The location of the Walt Disney World Resort in the south-east corner of North America.

The main mode of transportation for visitors of the resort is the Walt Disney World Monorail, a 23.66km/14.7mi network of elevated concrete beams for purpose built passenger trains to ride on. Opened in a shorter form along with the original park the system was extended as the resort expanded and now consists of 6 stations on 3 lines, connecting the Transportation and Ticket Center (the site of the main parking lot) with both the Epcot- and Magic Kingdom Park and 3 themed resorts. The whole layout has the shape of the number 8 tilted 45° to the left, with a transfer track connecting the Magic Kingdom Loop (which holds 2 lines, differing by the number of stops) and the Epcot-Loop at the Transportation and Ticket Center, while another transfer track in the northeast corner of the layout connects the Magic Kingdom Loop to the maintenance facility (which is off limits to the public). About two hours after the park closes each night the monorails cease operation, at which point trains from both loops will be parked at various stations or taken to the maintenance facility for maintenance, repairs and sometimes even new paint jobs.

The site of the accident seen from above, the transfer track between the loops can be seen at the very top of the image.

The trains involved

The Mark VI Monorail was introduced by Disney in 1989, replacing the older Mark IV. Why Disney started counting at 4 and skipped 5 is unknown. The trains were made by Bombardier of Canada and consist of 2 end cars and 4 shorter middle cars. Measuring 62m/203ft6in in length at 42 metric tons each Mark VI can carry up to 360 passengers, being set up to accommodate 20 seated and 40 standing passengers per car. The trains are fitted with eight electric motors fed 600V DC by a busbar on either side of the beam(think of the metal inserts on a slot car track), producing 100hp/75kw each. The trains are limited to 89kph/55mph, however Disney’s internal regulations only allow 64kph/40mph. Allegedly, each monorail costs 3.58 million USD/3.03 million Euros. The monorails have no conductor on board but do have a driver, which Disney calls the Monorail Pilot. When running on the loop the trains are guarded by a block-system based off the pylons holding the beam which measures the distance to the train ahead, called the MAPO. The name comes from the movie “Mary Poppins” (1964), as the movie’s profits paid for the system. An indicator in the driver’s console, looking somewhat like a traffic light, tells the driver if the next train ahead is 3 or more blocks ahead (green), 2 blocks ahead (yellow) or in the next block (red).

The control desk of a Mark 4 Monorail, with the MAPO on the left.

Each block is 150m/500ft long, with some stretching to 300m/1000ft. Guests riding in the front cab (which was allowed before the accident) can identify the beginning of a block by reflective tape around a pylon’s number and reflectors attached to the outside edges of the beam. Disney dictates that trains must be at least 2 blocks apart, if the MAPO-indicator turns red the computer locks out the driver’s throttle-control and initiates an emergency stop. Crossing into a new block under a red indicator is a safety-violation, 3 violations within two years mean a Pilot is moved to a different position and will no longer be driving the trains. However, similar to conventional railways’ block systems, the system can be disabled. This is done by a push-button on the console and is needed for navigating the switch tracks and moving into the maintenance-shed (which has beams without a busbar). A red indicator being ignored during switching, safety-tests or beam power loss does not count as a violation. The Monorail-system had a decent safety-record, a few times people on or near the trains had gotten injured, but no one had suffered serious injuries or died. The Mark VI trains feature several emergency exits, as the doors can be manually released, the large rectangular window in the center of each car can be pushed out and emergency hatches in the roof can be opened, allowing passengers to move along the roof to the next car (each car’s end walls are designed as fireproof bulkheads) or off the train to the surface of the beam. Despite their elevated track there are no ladders or slides integrated into the trains. After leaving the train passengers will either be guided along the beam to the next station by the pilot or wait for the fire department, which maintains a specialized offroad-capable ladder truck to ensure rescue off the beam at any point along the layout.

A sketch of the wheel setup, blue are the guide tires and red is the load tire.

Despite their visual similarity to Maglev trains the monorails are in permanent contact with the beam they ride on. Disney’s monorails use several Bogies with tires on 3 sides of the beam (similar to a roller coaster), a 22.5 inch “load tire” sits atop the beam and propels the train forward while smaller guide tires sit on either side of the beam, horizontally, and keep the train on track. This means that, despite being a train, the monorail uses rubber tires like a car. Each train has 12 load tires and 48 guide tires, split into wheelsets of one load-tire and four guide tires. This system makes it near-impossible for monorails to derail.

The monorails are named after a colored stripe running down their side, if they have an internal number/name it’s not known. Involved in the accident were the Monorails Pink and Purple.

Monorail Pink photographed at Epcot in March 2009,

The Accident

On the fifth of July 2009 at approximately 1:30am the monorail was finishing up operations after one of the year’s busiest days. Monorail Pink, holding only a pilot, was approaching the Transportation and Ticket Center from the south, followed by Monorail Purple which held a pilot and six passengers. Monorail Coral was also on the Epcot-Loop, but further back and does not play a role in the accident. As it held no passengers Monorail Pink was instructed to pass through the TTC-station, proceed a short distance, and then (overriding the block system) back over switchbeam 9 into the transfer track onto the Magic Kingdom Loop, as it was scheduled to head to the maintenance facility on the outer express-beam, letting it overtake other monorails parked along the way. As Monorail Pink stopped past the switchbeam as instructed Monorail Purple was directed to proceed into the station. As this brought it close to Monorail Pink the Purple Monorail’s pilot was instructed to override MAPO as he approached the station.

A graphic from the report showing the situation at 1:53am.

The switchbeams are operated from a control panel at the maintenance facility, on instructions from the central operation controller. To operate a switchbeam the following series of actions has to be performed:

  • Select the switchbeam on the control panel
  • Cut power to the beam
  • Order the change of alignment
  • Confirm command (power is re-established once the track aligns)

If the operator at the control panel does not perform the series of tasks in somewhat quick succession the system times out, making the popup window for the realignment of the switchbeam disappear and allowing the system to operate as it did before.

The control panel for the Epcot-Loop, a red indicator means the beam is receiving power.

At 1:54am the operator at the control panel confirmed his superior’s order to realign switchbeams 8 and 9 to allow Monorail Pink to navigate the transfer track into the Magic Kingom Loop. However, after cutting power to the beam the operator was interrupted when, at 1:55am, the pilot of Monorail Silver radioed him that his train had tripped a sensor controlling the left side doors as it pulled into the maintenance facility. At this point the operator turned away from the control panel to enter Monorail Silver’s arrival into the logbook, along with the tripped sensors. At 1:56am the pilot of Monorail Red also radioed in as he approached the facility asking for instructions and was to hold outside the facility. Returning to the control panel the window for the switchbeam operation had disappeared (as the sequence timed out), but the operator erroneously assumed he had completed the realignment. He reported as such to his superior, who ordered Monorail Pink to begin reversing. The central operation controller didn’t see the position of switchbeam 9, and as the Monorail reversed “blind” with the pilot in the forward cab (and no camera or assistant in the rear) the pilot was unable to spot the error also. As Monorail Pink’s pilot overrode the MAPO-system and began to back up the accident was doomed to happen.

A graphic from the report showing the tragedy take its course.

While the pilot of Monorail Pink possibly didn’t initially realize that he had failed to cross into the transfer track and was re-entering the station on the wrong track the data-logger aboard Monorail Purple indicates that Mister Wuennenberg, the 21 years old pilot of Monorail Purple, saw the pink train coming towards him. Just as Monorail Purple pulled into the station he stopped his train and pulled the throttle-lever into reverse, trying to avoid a collision. Too late. Monorail Purple was at a standstill when, at 2:00am, Monorail Pink reversed into it at speed. The protruding nose and driver’s cab of both trains was crushed as Monorail Pink’s momentum pushed the two trains back, killing Monorail Purple’s pilot on impact. The passengers as well as Monorail Pink’s pilot were uninjured.


Disney World employees on the platform got visitors out of the Purple train and off the platform, as they were trying to find out if anyone had survived in the crushed driver’s cabs they also had to get visitors to stop standing around filming the crushed section of the train. A few minutes after the accident professional responders arrived at the site and started picking the trains apart, but they could do nothing but confirm the death of Mister Wuennenberg. The entire driver’s cab protrudes past the frame in the shape of a streamlined nose cone, the collision had completely obliterated that protruding section on either train.

A photo of Monorail Green being towed, with the point to where the monorails in the accident were destroyed. You can see the small Mickey-symbol in the photos of the wreckage.

The NTSB (National Transportation Safety Board) soon had investigators at the site, with their attention turning to operation procedures that would allow the trains to get this close to one another in the first place. Despite often being seen as “gimmicky”, as an amusement ride rather than serious transportation, monorails are treated as railways and their incidents are subjected to the same scrutiny as those of conventional railways. It didn’t take long for investigators to find out that the radio-conversation that precedes and accompanies the movement from the Epcot-Loop over the transfer track onto the Magic Kingdom Loop is scripted and to be followed in its entirety. This script encompasses the pilot exiting the train at the TTC-station on the Epcot-Loop, moving to the opposite cab, reversing out onto the beam blindly, moving forwards over the transfer track and into the Magic Kingdom Loop’s track of the station, changing driver’s cabs again and proceeding counter-clockwise down the Magic Kingdom Loop (or elsewhere). However, when he was interviewed following the accident the pilot of Monorail Pink said that the script wasn’t strictly adhered to all the time, as the employee at central operation control would decide if, where and when you would switch between cabs if at all. It is assumed that, with the train being empty, it was decided to let Monorail Pink pass through the station without stopping and have it navigate the transfer track blind in order to save time. In fact, with the setup chosen that night he would have proceeded blindly through two stations all the way to the Grand Floridian Resort station and then change cabs.

A headrest pinched between the bulkhead and a piece of Monorail Pink, the driver’s cabs were truly gone.

Furthermore, it was found that the central operations controller on duty the night of the accident was not at his position while he orchestrated the shunting operation. Usually he was positioned at the Epcot-Loop side of the TTC-station, in a room equipped with indicators for the switchbeams and a surveillance camera feed from switchbeam 9. However, a few minutes before the accident the controller on duty had reported to his superiors that he felt ill and had been allowed to go home, with a replacement being told to come to work on short notice. In the meantime the monorail manager filled in on the job, but not from the usual room but by phone from a local restaurant without access to any of the surveillance-equipment. Shockingly, this was found to be in line with Walt Disney World Resort’s guidelines, which merely recommended that the controller be in the control room. It wasn’t mandatory.

At the same time investigators questioned the operator who had been at the control panel they found that protocol did not require the operator to ensure the switchbeam had realigned, “common professional certainty” was sufficient. The operator has access to the surveillance camera feed of switchbeam 9, and he stated that he had pulled up the feed before realigning the track to ensure the moving piece was clear of any vehicles. According to his statement he had been trained to use the feed to ensure the switchbeam was safe to operate, using it to ensure proper alignment was expressively optional. Asked if he had looked at it after returning to his control panel he said he couldn’t remember, instead again expressing that he had been taught to mainly use it before ordering a realignment.

The day after the accident the investigators re-enacted Monorail Pink’s movements (using a different pilot, as the one involved felt unfit for work) with a different train and noticed that not only the approach to the station on both loops would appear very similar when backing into it, but that a slight downhill grade into the station also meant the monorail would pick up speed as it approached the station. The pilot of Monorail Pink reported being focused on the monorail’s speed as exceeding 24kph/15mph while in MAPO-override mode would auto-stop the train and register as a safety-violation. Furthermore, the pilot stated that ahead of the accident the windows of the train were fogged up and there was little to no illumination around the beam, making it hard for the pilot to determine his position on his own. It was determined that he was not at fault for the collision, and that fault was split between the operator at the control panel, the central controller and Walt Disney World Resort itself for professional negligence and insufficient safety standards. OSHA (Occupational Safety and Health Administration) imposed an undisclosed fine on Walt Disney World Resort in reaction to the accident.

As the Monorail System reentered public operation the 6th of July 2009 a number of changes were implemented to avoid a repetition of the accident. These include:

  • Monorails are no longer allowed to back over switchbeams blindly
  • Monorails can only back up if a dedicated “spotter” is present in the rear cab, within the station, on the ground, or on a separate vehicle on the beam and directs the pilot by radio. A reprogramming of the monorail software allows usage of the kill switch in the rear cab
  • Monorail drivers are to visually confirm the realignment of a switchbeam
  • MAPO-override outside using switchbeam requires manager approval
  • The central controller has to be in the control room
  • A second operator must observe his coworker at the control panel
  • Usage of the surveillance cameras to ensure proper realignment of a switchbeam is now mandatory
  • The cleaning-procedure for the windshields was changed to reduce fogging and the air conditioning system was adjusted
  • The monorail manager on duty cannot leave Disney Premises
  • Surveillance cameras were installed at all switchbeams
  • Anyone involved in monorail operation can now auto-stop all trains via a radio-signal

After the accident Disney retired the colors Pink and Purple from the fleet. The undamaged parts of both trains were used to create Monorail Teal, introduced in November 2009, followed by Monorail Peach (using remaining middle cars with new end cars) in October 2011. After the accident Disney stopped allowing guests to ride in the cab of the trains.

Monorail Teal photographed in service in January 2010.

Today the monorail-system at Walt Disney is the third-most heavily used monorail in the world with over 150 thousand daily riders (as of 2016), surpassed by the Tokyo Monorail in Japan (300 thousand daily riders) and the Chongquing Rail Transit Monorail in China (900 thousand daily riders). Bombardier also delivered trains near-identical to those used by Disney to the Las Vegas Monorail, except for the trains in Las Vegas running autonomously for years, something Disney only relatively recently started introducing (for now still with a pilot watching over the computer). Furthermore, the Las Vegas Trains feature a slightly different, less protruding nose design.

In 2020 a book about the Disney monorail also hinted at a new generation of monorail-trains, the Mark X (why they skip 7, 8, 9 is unknown) to be introduced when the new “Play!Pavillion” at Epcot opens in 2021. But the book had been written before the Covid-Epidemic, and with the industry-wide crisis caused by the Epidemic it’s unknown if the new trains will debut this year or be delayed as Walt Disney World has seen various budget cuts and cancellations.

The Mark X monorail being advertised in the 2020 book “The Disney Monorail: Imagineering a Highway in the Sky” (2020).

Today nothing at the site of the accident points to the first (and so far last) fatal accident in the Monorail’s 38 year history, similar to how other deaths that happened at the parks are not acknowledged at the site.


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Max S

Train crash reports and analysis, published weekly.