* Second free practice wiped out
* Drivers get a total of 22 minutes running time
* Session abandoned as medical helicopter unable to operate
The Shanghai weather all but wiped out the first two practice sessions for the Chinese Formula One Grand Prix on Friday with poor visibility in the city forcing the grounding of the medical support helicopter.
Drivers were able to run for only 22 minutes in total during the 90-minute opening session with the second wiped out altogether.
Visibility at the track, on the outskirts of Shanghai, was good enough for helicopters to fly, with television choppers hovering overhead throughout the day.
Foggier conditions in the city meant the medical helicopter would have been unable to land at the designated hospital, though, a spokesperson from the sport's governing International Automobile Federation (FIA) said.
Track action has to be halted if the medical helicopter cannot fly, according to FIA procedures.
Teenager Max Verstappen’s opening session-topping effort of one minute, 50.491 seconds in damp and drizzly conditions, therefore remained the fastest time of the day, with only 14 drivers registering a lap.
The Dutchman's time was more than 15 seconds slower than Nico Rosberg needed to secure pole position for last year's race, an indication of the limited usefulness of the curtailed session.
Neither championship favourite Lewis Hamilton of Mercedes nor Ferrari’s Sebastian Vettel, winner of last month’s season-opening race in Australia, set lap times.
The two are expected to battle for victory on Sunday but will have only Saturday's final hour-long practice session ahead of qualifying to prepare for what is predicted to be a wet race.
With track action curtailed, fans who braved the cool temperatures and inclement weather found other ways to amuse themselves.
A fan dressed as Darth Vader, the villain from the Star Wars
movies, was given a fair bit of airtime with producers even running the caption "Darth Vader, Sith Lord" along with the images.
Hamilton crossed the track over to the grandstands, waving to his cheering fans and throwing signed merchandise to them.
The Briton, the most successful driver in China by far with four wins, is hoping to strike back at a resurgent Ferrari on Sunday.