Air Fence Safety Performance - Research?

[Hel'n'Back]

This is a genuine question that we need accurate answers for..... Air fences need to be installed correctly so that riders don't go underneath it, even if the bike hits it first, as has happened in some cases, but then a rider could bounce off it and then a rider behind run into him?

[chunky]

I always thought that the old wooden safety at Ipswich was as good as any air fence there.

 

I always felt the same about the fence at Wimbledon...

 

Steve

[iris123]

Surely the fact that we often hear riders take more chances as they think airfences are safer is proof enough.Unless people are just saying this and riders don't take more chances as they don't think airfences are safer.Sure i read somewhere that at least Tony Briggs tested his fences personally by riding into them

 

I know when asked about a rider for the PL he told me he wouldn't ride on tracks without an airfence.

Edited September 12, 2013 by iris123

[Vince]

I think it is a good to question the safety of air fences. Obviously we have all seen some spectacular incidents over the past few years where you immediately think that the air fence has saved a rider from serious injury. However while that may often be the case it is also often the case that you see riders walk away from spectacular crashes involving wooden fences, it is wrong to just assume that every rider who goes into the air fence hard would have been seriously injured had it been another type of fence.

 

There is still a major issue with riders going underneath the fences and this has been a known problem for a number of years and has caused some horrible injuries.

 

My opinion would be that air fences are a very good thing when properly installed and with something solid behind them. However that clearly isn't always the case and there are improvements that really need to be made before it can be automatically considered to be the best option. Again only my opinion that there are other fences, Rye House being my favourite, that are as good if not better than many air fences.

 

Opinions, including mine, are all very well but like the original poster I believe that there needs to be facts to back it up. Just assuming that air fences are the best option because running into a bouncy castle is better than running into a wall is not really common sense at all.

[Leicester Lion]

Zdenek Kudrna is not a good example here; he was killed at a grass-track meeting without a solid fence. Many of the tragedies at Hackney were the result of hitting lamp standards, although I'm not sure that Denny Pyeatt did. Even with an air fence, it is possible for a rider to go over the fence.

 

Having witnessed Leif Wahlmann's fatal crash, I certainly feel that an airfence at Saddlebow Rd back then could certainly have prevented that.

 

Steve

I remember Leif Wahlmann's crash, his bike suddenly slowed going into turn 1 and he was hit from behind by another rider close to the inside line. I'm not so sure that an air fence caused his head injury, it may have been caused by the initial impact from the other rider or the resulting melee before reaching the fence. Without knowing exactly what the cause of his head injury was, it can only be speculation about whether an air fence would have made any difference.

 

I expect the airfences probably are safer if the riders feel they are, but I think proper research should be carried out. Impact at various angles, different velocities, different materials behind the fence, etc should be scientifically tested to identify any areas for improvement. Even with detailed testing, it would be hard to draw any meaningful comparison with fences from the past as there have been some significant changes (for example, the machinery, the riding style and the racing line) since those days.

[Daniel Smith]

This is a genuine question that we need accurate answers for..... Air fences need to be installed correctly so that riders don't go underneath it, even if the bike hits it first, as has happened in some cases, but then a rider could bounce off it and then a rider behind run into him?

 

This is the problem. Current Air Fences do have a flaw that would be impossible to fix, simply because they're full of air and their shape alters on impacted.

 

If anyone needs a safety fence for next season please use the more modern version (Like King's Lynn & Berwick) of the PolyFoam. This really is the way forward

[wildcatwillie]

There was an article in the Star a couple of years back , where Tony Briggs was developing a new type of barrier. It was very interesting and i'm sure he test it by riding into it. The thing is, air fences and the poly foam fences are great if you hit them right, a lot of the injuries are by the incoming bikes hitting the guys, and a great deal of injuries are result from hitting the ground at speed. Just looking at youtube footage of crashes proves there is a need for air fences in a lot of situations and they definatly have saved lives in my opinion, but I have also seen pretty tame looking crashes where nobody has been any where near the fence end up very bad.

[Grand Central]

This is the problem. Current Air Fences do have a flaw that would be impossible to fix, simply because they're full of air and their shape alters on impacted.

If anyone needs a safety fence for next season please use the more modern version (Like King's Lynn & Berwick) of the PolyFoam. This really is the way forward

 

This is exemplifies why the original question was justified; and why some of the facetious responses were a little unworthy.

 

There is not just one type of APD just like there was not just one type of wire mesh or one type of board fence.

If we are to progress on to find better and more safe alternatives then work on research into the various types needs to be ongoing.

Statistics need to be collated and analysed; as do accident reports.

 

To just say air fences are safer that seventies death- trap fences doesn't move us forward.

 

My layman's observations are that there is a wide variation in the performance of different APDs at different track upon different types of impact. Some APD seem to bounce into the air quite freely when hit by a machine and the following fallen rider then disappears under it and smashes into whatever is behind.

At other tracks they seem to remain more stable even with multiple impacts and continue to offer protection after the initial hit.

 

Some tracks seem to have attached their APD to a high grade fence that will still 'catch' the rider who goes under the APD whilst others seem to have just hung their's on the lethal-looking Stock Car girders.

 

One of things about H&S is that it needs to be be continually re-evaluated in light of real experience.

Just saying 'we bought an air fence in 2005 so we are sorted' is simply not good enough.

 

.

Edited September 12, 2013 by Grand Central

[The White Knight]

This is exemplifies why the original question was justified; and why some of the facetious responses were a little unworthy.

 

There is not just one type of APD just like there was not just one type of wire mesh or one type of board fence.

If we are to progress on to find better and more safe alternatives then work on research into the various types needs to be ongoing.

Statistics need to be collated and analysed; as do accident reports.

 

To just say air fences are safer that seventies death- trap fences doesn't move us forward.

 

My layman's observations are that there is a wide variation in the performance of different APDs at different track upon different types of impact. Some APD seem to bounce into the air quite freely when hit by a machine and the following fallen rider then disappears under it and smashes into whatever is behind.

At other tracks they seem to remain more stable even with multiple impacts and continue to offer protection after the initial hit.

 

Some tracks seem to have attached their APD to a high grade fence that will still 'catch' the rider who goes under the APD whilst others seem to have just hung their's on the lethal-looking Stock Car girders.

 

One of things about H&S is that it needs to be be continually re-evaluated in light of real experience.

Just saying 'we bought an air fence in 2005 so we are sorted' is simply not good enough.

 

.

 

Excellent Post Grand Central. I have learned a lot from it.

 

Anything that helps with Rider Safety has to be a good thing. I honestly believe that Air Fences, fitted properly, is the way to go.

[pawel115]

There are flaws is air fences that is fact but in my opinion they have saved numerous riders life or serious injuries in my examples it would saved the life of Artur Pawlak that is for sure there was actually article written about it in polish speedway weekly his only injury was severe brain injury sustained when he hit woodden fence at Zielona Gora he sustained no other injuries you can see his crash on YouTube and come to you own conclusion.

[arthur cross]

If anyone needs a safety fence for next season please use the more modern version (Like King's Lynn & Berwick) of the PolyFoam. This really is the way forward

 

Totally agree about the PolyFoam fence being much preferrable to any sort of "bouncy castle" air fence because it appears to make a vastly better job of absorbing the energy of a crash's impact into it rather than rebounding that energy back into the traffic of any riders racing behind the crashing rider(s) ... clearly, the PolyFoam design simply dulls the impact instead of rebounding it (or even worse, letting the crash victim slide under the bottom apron of a bouncy castle).

 

I've haven't been to King's Lynn since the installation of their PolyFoam fence but I've seen how well it works when Sky have been there .. I have seen Berwick's PolyFoam both in person and on Sky.

 

Crucially, both those tracks have no other circuit outside them as there's just the concrete infield at the Norfolk Arena and Berwick Rangers' football pitch at Shielfield Park ... hence the PolyFoam can be fixed permanently onto the fence separating the speedway track from the crowd.

 

It doesn't seem to be so easy (or practical) to keep setting-up and then taking-down a PolyFoam fence for each meeting at any tracks that share their action with greyhounds ... at these venues, the requirements of greyhound spectators along with betting-shop or tv-viewers mean the speedway safety fence must be either fully removable or a mesh-fence that enables the punters/viewers to see the dogs racing round the 2nd and 3rd bends.

 

I'd still prefer to have a bouncy castle rather than an old-style safety fence because I've no doubt the bouncy castle still does a very good job of cutting down the number of broken bones as well as reducing quite a lot of the damage to the bikes ... it just seems to me that the Polyfoam is an even better solution.

 

I can think of 3 crashes which resulted in very serious injuries despite a bouncy castle being set up ... Chris Holder's season-ending smash at Coventry in July as well as Luke Priest's horrible accident at Stoke a few years ago both showed how badly it can go wrong if the moorings of the air fence are wrecked upon impact ... meanwhile, Ales Dryml's crash at Oxford remains the closest Sky have ever come to live coverage of a speedway fatality and, as far as I can remember, his lengthy coma was more the result of being hit by someone who couldn't avoid him as he bounced back into the traffic.

 

One other aspect of any sort of air fence that has always really puzzled me ... why does speedway pad just the outside horseshoe of the bends themselves without gradually tapering that padding for the first few metres down the back straight or home straight ? !!

 

Given the speeds involved, surely the first section of fencing going into the each of the 1st and 3rd bends would be far better use if it was adapted to provide protection beyond each of the 2nd and 4th bends when riders gallantly fail to regain control as they try to straighten-up from getting out-of-shape while cornering ... think about it folks, how many crashes do you see finish up as early as the first couple of panels of the fencing on the 1st/3rd bends compared to how many crashes you see finish up with riders sprawled 20 yards down the back/home straight !!

 

Motor racing and motor cycling circuits worked out a long time ago to shape their gravel traps beyond their curves to help catch their crash victims ... so much of their vital research into safety depends upon working back from where crashes finish up to make more safety improvements instead of simply working forward from where the crash started ... going right back to the hideous days of Formula One in the 1960's & 1970's, they made huge progress once they fully understood the initial collision on the track was bad enough but it was nowhere near as dreadful as the trees, telegraph poles and other clutter only a few feet beyond the barriers.

[iris123]

You are never going to make speedway or any motorsport fully safe.Bikes go flying through the air and sometimes over the fence.We have had two incidents of bikes going over and into the crowd.All a bit lucky as even now floodlight pylons are built right near the track.Plough lane was a pretty safe track as not only did it have a super wire fence and a stock car track outside the speedway one,but the lights were overhead on wire.I even saw an ice speedway bike go over the fence a few years back and it was pure luck that it was on the bend where no spectators are allowed.I also witnessed a rider who stopped almost dead down the home straight and a following rider went straight into him and flew through the air.No fence is going to help these situations.It does seem though that air fences in most situations are better than none.In a few situations they might not be.

[Kester]

Correct which is what cycle helmets are designed to protect you from (and why in my opinion you should choose to wear one); however most fatalities on cycles are caused by being hit by a faster moving vehicle (or being crushed by an HGV)so don't kid yourself that wearing a helmet will prevent this.

 

So that begs the question are we all kidding ourselves re air fences?

 

Speaking as a cyclist who went head first through a car window at 30mph through no fault of my own I can say with confidence that I'm glad I wore a helmet. There are arguments about the injuries they may possibly cause but I think the benefits far outweigh the possible risks. Many car manufacturers argued that seatbelts were more dangerous in the 60's. I have metal plates in my body, skin grafts and quite a few scars, but I'm still here.

[Elephantman]

 

 

Speaking as a cyclist who went head first through a car window at 30mph through no fault of my own I can say with confidence that I'm glad I wore a helmet. There are arguments about the injuries they may possibly cause but I think the benefits far outweigh the possible risks. Many car manufacturers argued that seatbelts were more dangerous in the 60's. I have metal plates in my body, skin grafts and quite a few scars, but I'm still here.

 

I always wear a helmet but as you will be aware a number of organisations position cycle helmets as something they are not. I would never suggest not wearing one; the reference was used to demonstrate how when discussing safety the facts don't always back up the general beliefs.

[Starman2006]

Can anyone point me in the direction of the research that was done to verify that Air Fences offer more protection to riders than more traditional safety fencing? I'm getting a bit boring in my latter years and this stuff interests me.

 

Thanks

 

Yeh they are a great inovation, providing they are pinned properly, top and bottom, preferably with D clips at the bottom, 2-3 to each panel!!!

Edited September 15, 2013 by Starman2006

[The Voice Of Reason]

but thinking back to the 80s , you had pyeatt, alderton and Kudrna involved in fatal crashes in 1982 alone.

With all due respect, it wasn't the actual safety fence that killed Denny Pyeatt at Hackney. In a freak accident, his back wheel was clipped by Marvyn Cox going into bend 3; which threw Denny high into the air, whereupon he hit (head first) one of the flood-light poles. Unbelievably back then, the tyres around the base of the poles just didn't go up high enough. Would airbags have saved Denny? Quite possibly, simply because they would potentially have taken a lot more of the bike's impact; and not therefore thrown him so high (if at all) over the top.

 

And that's a misnomer I often see about airbags - that they make a rider bounce back into the path of other riders. In my experience, that simply isn't the case. Firstly, to hit the airbag generally means that the rider (and obviously his bike) are out on the furthest perimeter of the track. That isn't where guys tend to ride these days. But more importantly, as already mentioned, the airbag AND the restraining straps on the posts are designed to move; and as well as taking the weight/momentum of the impact, they actually deflate enough momentarily so that a 'bounce back' (in most instances) doesn't occur. The restraining straps themselves are a similar material to a seat-belt in your car; and they clip/unclip easily into place. Just to add, these straps are not actually fixed to the wooden posts - they tend to run through u-shaped brackets - so that they have added 'give'/movement.

 

At the bottom of the air bags (certainly the Briggo ones that Lakeside uses), there is a very thick, heavy-duty rubber flap that lies flat against the shale, and holds the airbag down. However, fluke accidents can occur, even with airbags. Only a few seasons ago, Niels Kristen-Iversen hit one at the base and it actually lifted - sending him head first through onto the stock car track. Fortunately, he wasn't injured and could actually see the funny side of it when I went to check out his crash helmet for damage.

 

I think that potentially, their major disadvantage is when a rider lands completely underneath one; and is potentially trapped with his bike on his body. Although the cut-out should disengage the engine immediately (and cut-outs are ALWAYS checked pre-meeting when the bikes are warming up) the heat of the exhaust, engine and particularly the silencer are tremendous. Whilst the material used on airbags is non-flammable, a bike can certainly melt holes into them. And whilst kevlars are designed to withstand considerable heat, I have noticed that there are a number of occasions when they've tended to cut/split quite easily. Burning parts on bare skin are therefore a nightmare scenario - hence the reason that as track-staff, you are trained to get that thing lifted up pretty damn quickly and get the bike away from the rider (if necessary). And believe me, both airbag and bike are extremely heavy bits of kit. It's also frustrating when you have to wait for that bloody red light to come on - refs are generally exceptionally quick but, at times, it seems like an eternity. Just an added bit to bore you with - track staff can make absolutely no contact with the rider - even if he's crying out on agony (as they often are when they first hit the deck). That's entirely the responsibility of the medical team. However, it does enable you to learn just one or two swear words in Scandinavian and Polish, etc.!

Edited September 15, 2013 by The Voice Of Reason

[Starman2006]

With all due respect, it wasn't the actual safety fence that killed Denny Pyeatt at Hackney. In a freak accident, his back wheel was clipped by Marvyn Cox going into bend 3; which threw Denny high into the air, whereupon he hit (head first) one of the flood-light poles. Unbelievably back then, the tyres around the base of the poles just didn't go up high enough. Would airbags have saved Denny? Quite possibly, simply because they would potentially have taken a lot more of the bike's impact; and not therefore thrown him so high (if at all) over the top.

 

And that's a misnomer I often see about airbags - that they make a rider bounce back into the path of other riders. In my experience, that simply isn't the case. Firstly, to hit the airbag generally means that the rider (and obviously his bike) are out on the furthest perimeter of the track. That isn't where guys tend to ride these days. But more importantly, as already mentioned, the airbag AND the restraining straps on the posts are designed to move; and as well as taking the weight/momentum of the impact, they actually deflate enough momentarily so that a 'bounce back' (in most instances) doesn't occur. The restraining straps themselves are a similar material to a seat-belt in your car; and they clip/unclip easily into place. The straps themselves are not actually fixed to the wooden posts - they tend to run through u-shaped brackets - so that they have added 'give'/movement.

 

At the bottom of the air bags (certainly the Briggo ones that Lakeside uses), there is a very thick, heavy-duty rubber flap that lies flat against the shale, and holds the airbag down. However, fluke accidents can occur, even with airbags. Only a few seasons ago, Niels Kristen-Iversen hit one at the base and it actually lifted - sending him head first through onto the stock car track. Fortunately, he wasn't injured and could actually see the funny side of it when I went to check out his crash helmet for damage.

 

I think that potentially, their major disadvantage is when a rider lands completely underneath one; and is potentially trapped with his bike on his body. Although the cut-out should disengage the engine immediately (and cut-outs are ALWAYS checked pre-meeting when the bikes are warming up) the heat of the exhaust, engine and particularly the silencer are tremendous. Whilst the material used on airbags is non-flammable, a bike can certainly melt holes into them. And whilst kevlars are designed to withstand considerable heat, I have noticed that there are a number of occasions when they've tended to cut/split quite easily. Burning parts on bare skin are therefore a nightmare scenario - hence the reason that as track-staff, you are trained to get that thing lifted up pretty damn quickly and get the bike away from the rider (if necessary). And believe me, both airbag and bike are extremely heavy bits of kit. It's also frustrating when you have to wait for that bloody red light to come on - refs are generally exceptionally quick but, at times, it seems like an eternity. Just an added bit to bore you with - track staff can make absolutely no contact with the rider - even if he's crying out on agony (as they often are when they first hit the deck). That's entirely the responsibility of the medical team. However, it does enable you to learn just one or two swear words in Scandinavian and Polish, etc.!

 

Unfortunately mate your wrong about the Briggo airfence, we have one at Poole. Yes the rubbers do go right down to the track, but you have to keep a bit of shale on them during the meeting to help keep them down, then after heat 15 it can be all raked off. They also have D clips at the bottom of the panels at the back, 2-3 for each panel, and H clips for the tops, the fence won't move anywhere, we've had a couple of 3 testers. But you still have to check them, every week.. so im told. Very good fence's well recomended to any PL club looking to purchase a FIM Airfence.

Edited September 15, 2013 by Starman2006

[The Voice Of Reason]

You are right about some shale being placed on the rubbers to hold them in place. However, one thing that we've done is to drill and double-affix the rubbers with cable ties - the Velcro fixing is insufficient in our book. And the clips on Lakeside's are different than you describe.

 

As far as I'm aware, Lakeside's is a first generation Briggo; they are zipped together and the plastic clasps are all the same design - namely male/female. The outside of the bag is also attached to the retaining straps with metal spring clasps. These have a lovely tendency to rust and subsequently stick during the course of a season. Unzipping the airbags at the end of the meeting is a nightmare. If anyone can imagine a thick metal zip (often with some teeth missing) and caked in wet shale, there's no surprise that it's one of the tasks that's hated by most.

 

Just to add that unlike many tracks, Lakeside also has to build the track each week, and take everything down at the end of the meeting - given that the venue is also a banger car circuit.

Edited September 15, 2013 by The Voice Of Reason

[Starman2006]

You are right about some shale being placed on the rubbers to hold them in place. However, one thing that we've done is to drill and double-affix the rubbers with cable ties - the Velcro fixing is insufficient in our book. And the clips on Lakeside's are different than you describe.

 

As far as I'm aware, Lakeside's is a first generation Briggo; they are zipped together and the plastic clasps are all the same design - namely male/female. The outside of the bag is also attached to the retaining straps with metal spring clasps. These have a lovely tendency to rust and subsequently stick during the course of a season. Unzipping the airbags at the end of the meeting is a nightmare. If anyone can imagine a thick metal zip (often with some teeth missing) and caked in wet shale, there's no surprise that it's one of the tasks that's hated by most.

 

Just to add that unlike many tracks, Lakeside also has to build the track each week, and take everything down at the end of the meeting - given that the venue is also a banger car circuit.

 

Yeh ours have zips, im not to sure about that design. what you mean is you cable tie the overlapping rubbers?

[THE DEAN MACHINE]

there does need to be some research into the fitting of airfences and whats behind some of them (lifting up) but the airfences are by far the best fence at any track ,trust me i know ive tested one to the full. check out my profile picture .im the one in white not the one on the ground. that would of ended a lot worse without an air fence

Edited September 17, 2013 by THE DEAN MACHINE