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Side impact protection?
David Jenkins - 31/10/16 at 10:18 PM

This post was started as a result of this nasty crash - I didn't want to clutter up that discussion, so I thought I'd start one here...

The seven-style car gives pretty good driver/passenger protection from impacts in most directions apart from the area between the rear wheel and the windscreen - any impact there is likely to crush the occupant very badly, especially if the car hits a tree or post.

Has anyone had any thoughts about ways of protecting the sides, without losing the soul of a seven-style car?

Note: a side impact with a tree or post is bad in any car - a neighbour of mine was killed when the Sierra in which she was the passenger slid sideways into a tree - but is there some way of mitigating the force of an impact to reduce the damage to the occupant?


INDY BIRD - 31/10/16 at 10:27 PM

Did this on my mk may or may not help but still worth it, and it's not too ott in my opinion

MK INDY S2000 RR
MK INDY S2000 RR


rf900rush - 31/10/16 at 10:40 PM

Dax fitted , what they call Side impact bars.

DAX1
DAX1


Just glad I have never proven the function.
Sadly sold now.

The only sure way to know how save cars are is some sort of crash testing, but unfortunately this is very expensive.

Even with this, side impacts are never going to be safe , there is not much distance to reduce the 'G' force involved.


Slimy38 - 1/11/16 at 07:47 AM

I'm planning on doing something similar to the Dax, but because it'll have a full body on it I'm hoping the side bars will be hidden inside the bodywork. Obviously with a standard seven it's a bit more difficult to have discreet protection. It'll be part of the rollcage in the same way, I just haven't quite figured out how!

I like the 'diagonal' aspect of it, to me that seems like it's likely to deflect the impact rather than try and absorb it.


motorcycle_mayhem - 1/11/16 at 09:06 AM

Jeremy Philips had this covered on the Riot. Some had a very safety-committee add-on looking 3-point bolted on contraption, per side. Others had a bar incorporated very nicely as part of the chassis, retaining the good looks ('good' being subjective here, but it looks good to me).

Westfield (et. al.) have full cages to achieve a good level of race protection, albeit at some visual aesthetic cost.

Ford, Vauxhall, Volvo, etc., build lovely modern cars with far more side protection than the usual 7-type. This is what you really need, I guess, if anyone is squeamish about getting hit (or hitting things).


russbost - 1/11/16 at 09:24 AM

It's not easy to do something that is effective & aesthetically pleasing if you're adding it in on an already built chassis, though I think the Dax side impact bars look like a good job.

If it's being done at the design stage it's relatively easy to improve side protection without losing the look of the car, just making the top chassis rail 50 x 25 instead of 25 x 25, with the wide dimension being horizontal, or a 50mm dia circular section top rail, would make a massive difference & by the time it had bodywork over would barely notice, but it does still leave the problem that the sides themselves are very low, though you could bring a bar forward from the roll hoop to the screen base, but it's not going to look pretty or be particularly easy to negotiate getting in & out

You have to remember that when the car was originally designed, there wasn't much traffic around to drive into it, (plus Colin Chapman wasn't overly know for his protection of drives!) things are somewhat different nowadays.

If you imagine the result of being hit from the side in a 7 by one of these high fronted "truck like" SUV's or 4 x 4's which seem to be all the rage with school run Mum now, it doesn't bear thinking about, I'm pretty sure all the plastic on the front of the truck would compress & disintegrate & the whole front would go straight across the cockpit of the 7, the only thing that's going to give significant protection against that sort of impact is a full cage, in which case you would simply be pushed sideways down the road as being the lighter vehicle

I guess it depends how much driver (& passenger) safety you are happy to live with or without, that case where the guy has just been jailed for 10 years cos he was looking at music on his mobile phone b4 he ploughed into the back of stationary traffic & killed 4 people brings it all home a bit - it really doesn't matter what you're driving if you get sandwiched between 2 trucks, when travelling on dual carriageways & motorways I try to avoid ever being between a pair of trucks if I possibly can - defensive driving is probably more effective than any crash protection


motorcycle_mayhem - 1/11/16 at 09:36 AM

As I've said before (I live on a bend, approach road to a school), I see Mum in her SUV, kids on board, driving at speed, on the phone, completely oblivious, traffic calming meaning nothing to these monster trucks. Two of them approaching from either arm of the corner usually results with carnage, daily.
She wouldn't even sense the impact your 7 would create if it got in her way.

Mind you, Mitsubishi EVOs and 7's on a trackday always looks a bit iffy too...


dinosaurjuice - 1/11/16 at 09:40 AM

Crash protection on all kit cars is fairly minimal... the strongest chassis in the world would just kill the driver through high deceleration of organs

I just like to think its safer than a motorbike, unless its a BMW C1....


Doctor Derek Doctors - 1/11/16 at 10:12 AM

The Life Taker (my old sprint car) had a side impact bar made by Caged along with the full race cage.

Thoresby TLT 2
Thoresby TLT 2


Andy D - 1/11/16 at 11:06 AM

I had a relatively light sideways bump at Rockingham earlier this year, towards the end of this vid:
https://www.youtube.com/watch?v=gfauitvEMfc

When you see how far my head moves, I do wonder what would have happened if I'd hit on the other side?

Years ago I went to a gathering of Westfields for a run out. One car failed to turn up. It transpired the lad had spun his car sideways into a lamp post at relatively low speed. Minimal damage to the car, but the lad had smacked his head on the lamp post with fatal results.


David Jenkins - 1/11/16 at 11:19 AM

quote:
Originally posted by dinosaurjuice
I just like to think its safer than a motorbike, unless its a BMW C1....


My wife was happy when I replaced motorbikes with my Locost - it's a bit better than a bike, but not a huge amount better.

The main problem with this type of car is a big truck - they could drive straight over you.


Slimy38 - 1/11/16 at 12:54 PM

quote:
Originally posted by russbost
You have to remember that when the car was originally designed, there wasn't much traffic around to drive into it, (plus Colin Chapman wasn't overly know for his protection of drives!) things are somewhat different nowadays.


Maybe somewhat apocryphal, the original 'rollcage' was intended to protect the engine rather than the driver as engines were considered more valuable...


sdh2903 - 1/11/16 at 01:00 PM

I think a sideways on impact with something narrow such as a lampost or tree is always going to be bad in a 7. Even with a side bar. Lets face it you buy and drive a 7 for the driving experience not its Ncap rating.


benchmark51 - 1/11/16 at 03:54 PM

Driving a 7 or any other lightweight car is hazardous, but this is why we do it.
Much of the fun is in the risk just like many other pastimes and we can all choose not, but we won't.


GaryM - 1/11/16 at 05:12 PM

Do MK Indys have welded steel plate or riveted sheet Aluminium floors?


Sam_68 - 1/11/16 at 05:31 PM

quote:
Originally posted by Andy D
I had a relatively light sideways bump at Rockingham earlier this year, towards the end of this vid:
https://www.youtube.com/watch?v=gfauitvEMfc

When you see how far my head moves, I do wonder what would have happened if I'd hit on the other side?

Years ago I went to a gathering of Westfields for a run out. One car failed to turn up. It transpired the lad had spun his car sideways into a lamp post at relatively low speed. Minimal damage to the car, but the lad had smacked his head on the lamp post with fatal results.


The is a very pertinent post.

All the hip-level side impact bars in the world aren't going to help you if you headbutt the front of an SUV or a lamp post hard enough, and depending on the direction of impact, roll cages can actually worsen the scenario in a road accident.

The moral of the story is: if you're worried about personal safety, don't drive a 'Seven'.


CosKev3 - 1/11/16 at 05:44 PM

Yeah your head is the biggest risk.

Wonder if the triangle top of that sign has hit him?

Could be what's broken the rear arch too if that's come down at speed


CosKev3 - 1/11/16 at 05:44 PM

quote:
Originally posted by GaryM
Do MK Indys have welded steel plate or riveted sheet Aluminium floors?


Riveted alloy floor yeah


David Jenkins - 1/11/16 at 06:12 PM

I suppose the only thing that would make a difference would be a crush zone - something that would absorb the energy as it's destroyed by the impact. Not easy to fit to the side of a seven...


Sam_68 - 1/11/16 at 06:17 PM

quote:
Originally posted by David Jenkins
I suppose the only thing that would make a difference would be a crush zone - something that would absorb the energy as it's destroyed by the impact. Not easy to fit to the side of a seven...


Fairly easy on something that resembles the Seven's progenitor, the Eleven, though (or, indeed, something like a Sylva Phoenix)... and you get much better aerodynamics as a bonus.

All you'd have to do is fill the sill mouldings with rigid foam or honeycomb material?


gremlin1234 - 1/11/16 at 06:20 PM

quote:
Originally posted by David Jenkins
I suppose the only thing that would make a difference would be a crush zone - something that would absorb the energy as it's destroyed by the impact. Not easy to fit to the side of a seven...
or air bags, (yea I know IVA doesn't allow them for non production cars) but maybe a development of the motorbike airbag/jackets/hoods could be done


Toprivetguns - 1/11/16 at 07:23 PM

One big regret was not buying the full roll cage with the MK. Safety and somewhere for the roof box would of been a bonus!


ettore bugatti - 1/11/16 at 08:38 PM

Googling "impact attenuator" and Hexcel should provide enough reading for this evening.

I thought FIA/MSA actually prescribe the design for the impact attenuators for some single seater classes, but I can't find it at the moment.


coyoteboy - 1/11/16 at 11:22 PM

Impossible to design for all impacts, but common ones, sure you can. And a strong chassis doesn't help in an impact. Impact attenuation can only help.


rm0rgan - 6/11/16 at 10:09 AM

quote:
Originally posted by dinosaurjuice
Crash protection on all kit cars is fairly minimal... the strongest chassis in the world would just kill the driver through high deceleration of organs
.


This ^^^

They say it's generally the 3rd impact in an accident that kills you....the first being the vehicle collision, the second the human collision within the vehicle and the third the internal collision....this is the one when the internal organs move towards the point of impact and hit other organs and bones on the way. Even though the body may appear intact and uninjured, the squashy stuff in us like the liver, spleen, heart, brain etc. may be torn, bruised and bleed as it makes its way to the point of impact.

Most people don't know how much force a moving vehicle has but to give you an idea, a car going 40 mph into a tree has the same force as hitting the ground after falling off a 50 foot cliff. A person inside that car would hit the windscreen with the same force as hitting the ground after a fall from a five-story building - your body would be close to terminal velocity! You would need a carpet cleaner to pick you up.

Stay safe folks!


steve m - 6/11/16 at 01:03 PM

I had never really thought of the side impact on our 7's
But had thought that even a mild tap up the rear, would be very nasty, especially as the fuel tank, is only 14"from my shoulders

steve


Matt21 - 26/11/16 at 12:13 PM

Has anyone made their own side impact bars?

I'm thinking of doing some for mine rather than paying someone else to do it.


Beardy - 17/7/18 at 03:47 PM

One option that I thought could be made to look acceptable and potentially useful would be the nice "clip on" bike luggage. When not touring you could have them on and filled with crap - or if you want to get clever some preformed compressible structural foam or similar. And when touring you could use them for luggage.
I was looking at a Riot / midlana type car at the time and I couldn't figure any way of carrying anything.


Mr Whippy - 18/7/18 at 06:04 AM

side protection was the reasoning behind me doing this on the old MK, it was rather wide though but did give me some where to put the two polo rads...

A 7's always going to struggle in this area, watch even Volvo crash tests and it's amazing how much damage is done and the window airbags help a lot. Best thing to do is just drive carefully in the first place and pay particular attention to situations that expose your side. The use of such solid lamp posts and sign posts should be banned and phased out, there are plenty of lightweight crush-able alternatives in use for years. I'm glad to see the new Aberdeen bypass is using them even for the largest of signs.




[Edited on 18/7/18 by Mr Whippy]


procomp - 18/7/18 at 06:05 PM

Just had someone on the phone who was reading this.

when we had the roll caged for the FIA/MSA designed for the Procomp LA's we came up against the problem of trying to meet the criteria required and offering maximum protection for driver. The other complication was that to meet the latest full FIA we had to have the Rollcage chassis and all mounting points meet FIA and as far as i know ours is still the only seven type chassis / rollcage to pass this test as apposed to just the cage being tested on its own.

The first problem was the cockpit side was not supported sufficiently and required the additional chassis bracing as we fitted to the westfield race chassis we developed for westfield, that gave sufficient strength to chassis to be used as a mounting point but only as a fully welded rollcage chassis combination as when bolted it didn't meet the criteria required in simulation.

However even with all this FIA testing and having actual accidents on track including 60mph side impacts i still would not be 100% confident when you involve street furniture kerbs and other associated things found in a road going situation compared to an on track accident where you are free of such items.

if interested there is a section on the old http://www.procomp.co.uk/ web page regarding the rollcage with drawings etc.

Cheers Matt


40inches - 18/7/18 at 10:34 PM

quote:
Originally posted by GaryM
Do MK Indys have welded steel plate or riveted sheet Aluminium floors?


Early chassis (mine) had welded steel bottom and bulkhead, later ones riveted ally sheet.