Jules Bianchi's father Philippe says that he is not convinced that the 'Halo' concept is the best solution for protecting Formula 1 drivers.
An early prototype of an F1 Halo design appeared on Thursday at Barcelona as Kimi Raikkonen tried it out for an installation lap to check on visibility.
And although there are clear safety benefits from the Halo, it is also widely accepted that it may not have been what was needed to save Bianchi's life after his 2014 Japanese Grand Prix crash.
Speaking to French television station CANAL, Philippe Bianchi welcomed safety efforts – but urged the sport to go much further in its quest to protect drivers.
"I consider that this is a step forward in term of safety," said Bianchi. "It is obvious that in the case of a wheel coming off, this system would be effective.
"However, in the case of small debris, like Felipe Massa [in Hungary 2009] and [IndyCar driver] Justin Wilson had, it wouldn't have changed anything. So this is a step forward, but it does not solve everything."
The nature of Bianchi's accident at Suzuka, when he collided with a track vehicle, means that a cockpit hoop may have made no difference to the outcome of his crash.
Philippe added: "For Jules, it would have changed nothing, because it was an extremely violent deceleration that caused the damage that we know happened to his brain.
"I think developments of the HANS device, to better absorb big deceleration in a severe impact, could help in this case."
Philippe added that he would not wish to stop a concept like the Halo from happening if it did improve safety, but he has urged the FIA to not rest on its laurels after it is introduced.
"It is obviously not me who would speak out against something that brings more safety to the drivers," he said. "But the version of this 'Halo' system did not convince me and has yet to be perfected.
"Aesthetically, it's pretty bad, and I wonder what the driver gets to see behind the 'Halo'.
"The FIA wished to act after Jules's and Justin's accidents, but it must go further."
Red Bull tests
The FIA is pushing on with plans to introduce the Halo concept in F1 from 2017, although a final design has not yet been approved.
Red Bull is due to trial its own version of the safety device – which is based more around a screen canopy that should allow better visibility for drivers.
The Milton Keynes-based team's boss Christian Horner believed that the design tried by Ferrari was not the right direction for F1 – especially because it would unlikely have changed the outcome of recent accidents in the sport.
"Personally I don't like it," he told Motorsport.com. "I understand that driver safety is absolutely of paramount importance, but for me I think I am a little bit more of a purist of open cockpit racing that has been there for 60 years - and there is danger associated with that.
"Of course we have to do everything we can to mitigate that. But the protection that is being looked at, the Halo concept, would not have helped Felipe Massa and, unfortunately, would not have helped Jules Bianchi."