The spectator who suffered a depressed skull fracture after being hit by debris at the Grand Prix of St Petersburg in March has opened legal proceedings against the Verizon IndyCar Series, seeking damages in excess of $15,000.

Brigitte Hofstetter was injured while standing in a concessions area with her husband Gregory. It's believed that on-track contact between two cars caused a piece of the new aerodynamic bodywork being used for the first time in a race that weekend to fly off and over the fencing around the track.

Mrs Hofstetter's suit seeks damages for pain, suffering and loss of consortium, a legal term typically referring to the deprivation of the normal benefits of a husband/wife relationship for a period following an accident. She is expected to make a full recovery in due course.

The suit is based on the allegation that IndyCar did not carry out sufficient testing of the new aero kits and failed to ensure that they were strong enough to survive even relatively light contact without detaching and flying off into spectator areas. According to the Tampa Bay Times, the suit alleges that the bodywork as raced that weekend was "extremely dangerous and unsafe."

In the week after the race, in light of Mrs Hofstetter's injuries, IndyCar mandated a number of changes to the aero kits provided by Honda and Chevrolet to improve their robustness and ensure the chances of any recurrence of what happened at St Pete were minimised.

The owner and operator of the event, Green Savoree, is also named in the suit on the grounds of not doing enough to warn spectators of the danger of attending the race. Many tickets for motor racing events routinely carry a warning as a legal requirement to remind fans that any high speed race is a potentially dangerous event that they attend at their own risk, but this case will test whether that is indeed deemed a sufficient waiver under Florida law.

Also targeted by the lawsuit is Smith Fence which provided the barriers around the circuit who are cited for not providing adequate protection for the spectators. The Hoffstetter's attorneys Justin C Johnson and Christopher M Rotunda previously indicated that the city of St Petersburg is also likely to be included in the action, but has not been at this initial stage.

The suit was filed in Pinellas County Circuit Court on Friday and would require a jury trial. IndyCar officials have made no comment so far on the legal action.