Red Bull changes pitstop procedure after Nurburgring accident

FOM cameraman Paul Allen suffered broken bones and concussion after being struck by the right rear wheel from Webber's car when a pitstop went wrong.

The incident has led to a clampdown on personnel access to the pitlane during grand prix weekends, with all television crews now banned while track action is underway.

Following a detailed investigation into the incident, which has been shared with the FIA and other teams, Red Bull discovered that the problem arose when the right rear wheel gun man's thumb accidentally triggered a 'go' signal - which meant the car was released early.

NURBURGRING INCIDENT EXPLAINED

The sequence of events that led to that moment began when the right rear wheel nut cross-threaded as it was put on the car.

With the nut not going onto the wheel, the gun man decided to remove it and replace it with another.

However, after switching his gun into 'undo' mode the torque level was much higher than previously experienced, which led to the gun slipping in his hand as he removed the nut.

This slippage led to the 'go' trigger - which is sent to the jack men to indicate that that wheel is attached - being accidentally depressed by the gun man's thumb.

At this split second, the nut was fully unwound - so the car was released from the pits with nothing holding the right rear wheel on.

CHANGES TO BE MADE

To prevent a repeat problem in the future, Red Bull will revise the design of its wheelguns so that in the event of it accidentally rotating in an operator's hands, their thumbs will be moved away from the 'go' signal button, rather than towards it.

Furthermore, Red Bull's pit controller has been instructed from now on that if there is any issue during a pitstop, that he must hold the car until he has been given a clear signal from the gun men that the wheels are attached.

The team is also investigating ways of ensuring that the 'go' signal cannot be activated while the trigger is depressed or the gun is in 'undo' mode.

Red Bull's current system has been in place for more than one year now, and the use of independent signals from the wheel and jack men is still believed to be safer than basing a decision on the front jack man alone.