From a legal standpoint. The suing chain should stop at the driver. It would not go beyond that.

I doubt they will be able to sue the airfield either. If a burglar trip and fell down the stairs because the house is dark, he can't sue the house owner.

Happens all the time.

Airfield would be considered an attractive nusiance. Failure to lock it up would be negligance. They would not be able to successfully sue John Travolta, but they might try just to get some settlement money. Owner of car first (dad), airfield, family who had party (if any alcohol was in bloodstream), engineer of airfield, company who maintained airfield, BMW, dealer who sold car and maintained car, and then John Travolta.

Car insurance limit of father will just be a starting point. Dead Carrera GT owner's estate in California ended up paying big time and only one passenger died.

Just the way it is.