Technical comments only: car to car crash safety

[roon]

Perhaps the monocoques could be weakened. Or at least, selectively so. If instead of thick energy absorbing materials, perhaps the safety cell could be design in the following way.

--The cockpit is lined with a large deflated airbag in which the driver sits. Think of it as shaped like a large sock or seedpod. Deflated it would be as spacious inside as a normal cockpit, ideally.
--When expanded, the airbag fills the void to the driver, as well as expanding outward through the walls of the monocoque.
--The breaking of the monocoque may be a passive or assisted process.
--The expanded bag may then extend widely past the driver, perhaps a meter or so in all directions.
--This inflated coccoon airbag might be permitted to detach totally from the cracked chassis

There may be some advantages to detaching the driver from the car masses totally. It reduces, or at least distributes, the impact energies. Which could help with the design requirements of the device.

The approach to car construction may need to change, and devices such as the halo may need to be rethought, but essentially: destroy the car to save the driver. The steering column potentially interferes. Locating the driver's arms during inflation would need to be considered.

If this device is robust/reliable enough, it might permit a different approach to car safety in general. If the car can be split open to eject a relatively low-mass encapsulated driver, then what need for high performance crash structures that must absorb the full weight of the car? The chassis, engine, gearbox, suspension, wings--these items do not need to be gently decelerated. Only the driver does.

Tire barriers (and their derivatives) could be rethought as a result. If the driver can slide, bounce, or roll to safety inside a coccoon, then the barriers could be made softer (needing only to absorb ~100kg at speed instead of ~700kg). The car would overload it and carry through to the concrete, but the driver would be detached at that point.

When crash structures begin to get involved, it is DNF time. The race is over anyway. So consider the car expendable and solve only for the driver and their coccoon.

[rscsr]

Has there been any thought to implementing SAFER barriers (https://mwrsf.unl.edu/safer.html)? These are designed to absorb energy without deflecting the car back onto the track. Used heavily on IndyCar and Nascar sanctioned tracks.

I know this technology has made it to a few F1 tracks.

yes in F1 it's called Tecpro, and yes it absorbs/converts energy whereas tyres store energy of course and return it to the car with a delay. it should definitely be part of the solution. It doesn't have to be everywhere. It's used in Monaco already.

TecPro barriers are not SAFER barriers.
This link analyses different energy absorbing barriers.

[Just_a_fan]

--The cockpit is lined with a large deflated airbag in which the driver sits. Think of it as shaped like a large sock or seedpod. Deflated it would be as spacious inside as a normal cockpit, ideally.
--When expanded, the airbag fills the void to the driver, as well as expanding outward through the walls of the monocoque.
--The breaking of the monocoque may be a passive or assisted process.

The monocoque would need to be weaker than the driver. If not, the inflating bag would crush him. An active failure of the monocoque prior/during bag inflation would require a further pyrotechnic. Failure of that would cause crushing of the driver. Incorrectly timed/partial activation crushes the driver or dumps him in to the open sat only in an uninflated bag for protection.

How is the bag to be inflated? Presumably pyrotechnically. That's a lot of pyrotechnic to fill a bag big enough to encapsulate a driver. How is inflation to be initiated? A crash sensor? Determining an inflation crash rather than a minor impact would be interesting. Max's impact on the barrier after Eau Rouge was big but easily a "hop out and say sorry to the team" event. Would you totally destroy a car for that impact? How does the driver escape from the bag? Controlled deflation or cut out by marshals? Do marshals then require breathing masks to protect them from the encapsulated pyrotechnic gases? What happens if the bouncing ball bounces in to the crowd?

Sorry, but such an active system is a non-starter for so many reasons. Any in-car protection of the driver needs to be passive and part of the car. That way you get predictable behaviour. And, yes, the Spa fatality was predictable if you test the correct scenario.

The main way to avoid high speed T-bone impacts is to prevent crashing cars bouncing out of the barriers. Even then there will always be situations that can't be prevented and expose a car to a high speed T-bone impact.

[Jolle]

--The cockpit is lined with a large deflated airbag in which the driver sits. Think of it as shaped like a large sock or seedpod. Deflated it would be as spacious inside as a normal cockpit, ideally.
--When expanded, the airbag fills the void to the driver, as well as expanding outward through the walls of the monocoque.
--The breaking of the monocoque may be a passive or assisted process.

The monocoque would need to be weaker than the driver. If not, the inflating bag would crush him. An active failure of the monocoque prior/during bag inflation would require a further pyrotechnic. Failure of that would cause crushing of the driver. Incorrectly timed/partial activation crushes the driver or dumps him in to the open sat only in an uninflated bag for protection.

How is the bag to be inflated? Presumably pyrotechnically. That's a lot of pyrotechnic to fill a bag big enough to encapsulate a driver. How is inflation to be initiated? A crash sensor? Determining an inflation crash rather than a minor impact would be interesting. Max's impact on the barrier after Eau Rouge was big but easily a "hop out and say sorry to the team" event. Would you totally destroy a car for that impact? How does the driver escape from the bag? Controlled deflation or cut out by marshals? Do marshals then require breathing masks to protect them from the encapsulated pyrotechnic gases? What happens if the bouncing ball bounces in to the crowd?

Sorry, but such an active system is a non-starter for so many reasons. Any in-car protection of the driver needs to be passive and part of the car. That way you get predictable behaviour. And, yes, the Spa fatality was predictable if you test the correct scenario.

The main way to avoid high speed T-bone impacts is to prevent crashing cars bouncing out of the barriers. Even then there will always be situations that can't be prevented and expose a car to a high speed T-bone impact.

Not just that, remember what happens when you put a tennis ball on top of a basketbal and drop them from a feet on a floor?

[turbof1]

The solution they brought forward to avoid crashes like Bianchi had, was to change procedures. Even though you can't prevent the current hazard with different procedures, there is certainly a case to be made for solutions outside the car.

The cars and barriers are made incredibly well for crashes. Correct me if I am wrong, but nobody even sustained significant injuries due to a high velocity impact with tyre barriers for a couple of decades now. That part is obviously working, and like JAF said, maybe we should focus on keeping the car off the track. Because we are talking about beefing up crash structure, adding air bags and what more. But, the car crashing first into the barriers and then being t-boned, which was the case with Hubert, means all the solutions will already be compromised.

Since we have the halo protecting the head of the driver, what about having the car purposely slide underneath the barrier and getting stuck there? This happened in the F3 race and although it was very difficult to extract the driver in a short amount of time, which can be a safety hazard, the driver came out unscathed, plus his car wasn't going anywhere being stuck underneath the barriers.

[zac510]

I'm surprised nobody has mentioned the weight of the car. Although I'm not overly familiar with the specs of F2, the current F1 cars being the heaviest in a few generations, must be carrying some added risk.

[Just_a_fan]

Mass of the car will have an effect on an impact, yes, but speed is the bigger issue. Dealing with crashes means safely dissipating energy and energy increases with the square of the speed (velocity). At the speeds seen at the top of Radillon in F2, reducing a car from 750kg to 700kg would be the same as reducing the speed from 170mph to 162mph. At 162mph, the accident would probably still not be survivable, all other things being equal.

It might be argued that adding 50kg of deformable structures around the tub would be better than removing 50kg from the overall car mass. It would be carrying a bit more energy from the added mass, but that mass could be made to work hard to dissipate the crash energy safely.

[Just_a_fan]

Moving on from a comment I made previously about adding structure to the side of the tub, something like the Jordan 196 comes to mind:


However, instead of the inner radiator duct, the side of the tub would be deformable structure, with the radiator duct outboard of that.

Of course, the central issue is that the aerodynamics of the modern cars demands that there is as much space between the front of the sidepods and the front wheels, and that the sidepods are as tight as possible with lots of undercut (void). There is very little bodywork of any substance between the tub and a side impact.

Thinking further, the sidepod's contents could be used as crash structure. A radiator is a pretty good crushable structure. Mandating the use of the radiator, along with other panels, could make the sidepod an effective side impact device.

[izzy]

There are two crumple zones to contribute tho - one in the nose of the striking car and one in the side of the struck car. These could add up to 1m or more, if the sport got determined about it.

Currently the side of the car doesn't give much protection in a T-bone incident unless the impacting car's nose hits one of the lateral crash structures. If this doesn't happen, the impact is absorbed by the impacting car's front impact structure (the nose cone), with the impacted car's chassis having to rely on the anti-penetration panel to keep the tub intact. All of the deceleration is done by the impacting car's nose, in effect. The anti-penetration panel is having to take a lot of load without splitting and this is probably the weak point in the system. The F2 cars pass the same crash tests as F1 cars do so we can be confident that if that accident had involved two F1 cars, we would be mourning an F1 driver today.

To add additional energy absorption in to the cars, we'd need to make the noses longer and / or add some panels on the side of the tub. I would suggest that longer noses would be easy if perhaps aesthetically unwelcome to many. Side panels would be easy to add but would change the aero designs of the car quite a bit - in effect the sidepods would be moved outwards and the gap between the sidepods and the turning vanes would disappear.

How well the side panels would work is somewhat dependent on the shape of the impacting nose cone, along with the stiffness of the side panel's outer skin. A stiff panel with a crushable core behind would help to prevent a simple penetration and would maximise the area over which the impact load was absorbed.

It's worth noting that the impacting car's nose was gone after the accident. Either it was totally crushed or it was ripped off by a lateral load. In either case, it left the impacting car driver's feet exposed to injury. I'm reminded of Kubica's crash in Canada in 2007 where the nose hit a concrete wall at a 45 degree angle (approximately), having glanced off an earlier wall impact that sheared off the front right suspension, and was totally destroyed. The concrete wall panel that he hit was moved backwards by the impact too, such was the energy involved. This would have been a similar speed to the Spa incident. Indeed, the whole accident is remarkably similar, except the wall was another car at Spa. It's no surprise that the F2 car was unable to protect the driver in such an impact. I'm not sure an open wheeled single seater ever could in such a circumstance.

Yes the cars have to change don't they. The nose has to come up and be more rounded and all the impact structures have to be the same height with a good tolerance so they engage. The crash tests have to be more realistic and much, much more severe - 33/22/25 mph is ridiculous. Yes 100% the nose has to stay on in an oblique impact, and the side impact resistance has to work in car-to-car collisions spreading the load as well as absorbing a lot of energy as it crushes.

They can do this tho. They like a 4.5m long car with the front wing way forward, that's a great start. It's 1.8 or 2m wide and a driver is only 0.4 or something at the hips, that's a lot of space too. They can design radiators with crush resistance etc etc. They can incorporate a beam into the front wing so it links across the front wheels...

As I've said before, in F1 they ought to drop the minimum weight and instead make it all crash test, but extremely severe, and let the teams work on it. Then the best of what they come up with can filter down to the spec series. For sure they can improve things massively from where they are at the moment, which is not joined up at all.

[Just_a_fan]

Having watched the Spa crash a couple of times now, it looked like the incoming car lifted as came in to contact with the side on car. The top of the side of the tub was missing after the crash. No idea why if did this other than being lifted by debris at the side of the car. With this in mind, I don't think one should try to say "all the crash structures will be at the same height". The whole side of the car has to be a crash structure that can deal with impact at the bottom, the middle or the top. This gives maximum tolerance for engagement.

[izzy]

The solution they brought forward to avoid crashes like Bianchi had, was to change procedures. Even though you can't prevent the current hazard with different procedures, there is certainly a case to be made for solutions outside the car.

Well for the Bianchi scenario they changed procedures AND did the secondary safety too, they just didn't wanna admit it! Halo would probably have saved him. I bet they had that crane in mind, secretly, when they made it take a load of 12 tons. So halo is recent and its standard is way, way higher than the front and and side impact tests that apparently were introduced in 1985. They'll get updated now, there'll be a big project.

[turbof1]

The solution they brought forward to avoid crashes like Bianchi had, was to change procedures. Even though you can't prevent the current hazard with different procedures, there is certainly a case to be made for solutions outside the car.

Well for the Bianchi scenario they changed procedures AND did the secondary safety too, they just didn't wanna admit it! Halo would probably have saved him. I bet they had that crane in mind, secretly, when they made it take a load of 12 tons. So halo is recent and its standard is way, way higher than the front and and side impact tests that apparently were introduced in 1985. They'll get updated now, there'll be a big project.

No, Bianchi would still have sustained brain damage due the heavy deacceleration. The halo was I believe already being developed before Bianchi and more as a response to the incidents of Massa and Surtees.

[izzy]

Having watched the Spa crash a couple of times now, it looked like the incoming car lifted as came in to contact with the side on car. The top of the side of the tub was missing after the crash. No idea why if did this other than being lifted by debris at the side of the car. With this in mind, I don't think one should try to say "all the crash structures will be at the same height". The whole side of the car has to be a crash structure that can deal with impact at the bottom, the middle or the top. This gives maximum tolerance for engagement.

well yes i totally agree this is why i said "the same height with a good tolerance so they engage" !!! Then if they're not all on the ground, at some point the halo has to take over.

but it's good you're coming round to the general idea

[izzy]

No, Bianchi would still have sustained brain damage due the heavy deacceleration. The halo was I believe already being developed before Bianchi and more as a response to the incidents of Massa and Surtees.

Bianchi's car didn't see a heavy deceleration, it stopped over 4.1m iirc. His ear saw a huge acceleration because his helmet glanced off the counterweight - edit and this is what a halo would have prevented or reduced.

Oh yes halo was being introduced in 2015 and Jules' accident was July 2014. At some point they raised the test tho, i think, from 94 to 112 kN

[Jolle]

No, Bianchi would still have sustained brain damage due the heavy deacceleration. The halo was I believe already being developed before Bianchi and more as a response to the incidents of Massa and Surtees.

Bianchi's car didn't see a heavy deceleration, it stopped over 4.1m iirc. His ear saw a huge acceleration because his helmet glanced off the counterweight - edit and this is what a halo would have prevented or reduced.

Oh yes halo was being introduced in 2015 and Jules' accident was July 2014. At some point they raised the test tho, i think, from 94 to 112 kN

The FIA did an in-depth analysis of all the crashes where the HALO might or might not made a difference. They did the analysis on Bianci's crash, the conclusions was that that crash was outside the operating window of the HALO, on balance no difference. On Massa's incident it was positive on balance, but only by 14%. Both incidents were countered by other regulation. In the case of Bianci, the VSC and for Massa the new zylon strip and the current helmet regulations.