Formula One's governing body is planning more tests on technology to protect drivers' heads from flying debris of the sort that killed British IndyCar racer Justin Wilson.
The International Automobile Federation (FIA) has tested various solutions since Brazilian Felipe Massa was hit on the helmet by a bouncing spring in Hungary in 2009, including cockpits enclosed by a fighter jet-style canopy.
The death of former F1 driver Wilson after he suffered severe head injuries at Pocono Raceway in Pennsylvania on Sunday has prompted calls for more protection for drivers, though an FIA spokesman said the new tests were already planned before Wilson's accident and would take time.
So far negatives such as obstructing a drivers vision or trapping them in the event of the car overturning have failed to outweigh the safety advantages, but the body plans to test two new ideas, one from world champions Mercedes that involves a 'halo' or hoop positioned above the driver's head.
"We have to persevere," said Formula One race director Charlie Whiting, the FIA technical head who is in charge of safety. "We must make something, even if it's not 100 per cent in terms of protecting the driver under all circumstances. If it improves the situation, it has to be good. There must be a way."
The long-standing debate on how to protect drivers' exposed heads was revived after French F1 driver Jules Bianchi died in July after suffering severe injuries when he crashed into a recovery tractor at Suzuka last October and Whiting said some sort of cockpit protection would be introduced eventually.
Bianchi's former Marussia team mate Max Chilton, who has raced most recently in the US Indy Lights series, agreed cockpits should be made safer in IndyCars.
"There is definitely room for making them closed cockpits," he told Sky Sports television. "I think we can come around and design something where we are safer from debris and head-on collisions into tyre walls or whatever it may be and we can still get out. I think this (Wilson's death) is definitely going to push that forward."
And Brazilian former F1 driver Lucas di Grassi pointed out on Twitter that closed cockpits need not necessarily be seen as a design compromise.
"Canopies will be used in every single formula (open-wheel) series in the future. Not only for safety, but for aerodynamic improvement," he said.