An alternative to sandtrap nets?

I'm new here but the loss of two of drag racing's good guys in the past month has saddened me and made me revisit a passing thought I had a couple years ago. See what you think . . .

After Scott Kalitta's mishap at Englishtown, I wondered if there was another method of safely slowing runaway cars. About that time, my son went to a birthday party and they had some of those big inflatables there so I checked them out.

The material was heavy rubberized cloth so I wondered if the same airbag' technology could be adapted to the task of slowing race cars safely in a limited area.

The nets currently in use by NHRA have inconsistencies built into them that result from their size, mounting and support systems, composition, tension or slack, web size and assorted other factors. An airbag system could be engineered to provide a more gradual and predictable slowing process.

Why airbags? Heck, I don't know but they're now used to keep people from bouncing off dashboards in car wrecks, provide places for pole vaulters to land, allow stunt people to dive off of high places and they’re also used for boat bumpers and many other applications where energy needs to be dissipated within a short distance.

The bags could be made out of ballistic rip-stop nylon with a flame-resistant outer coating. If they were designed to be inflatable, the air pressure could be controlled and monitored to control rigidity.

As far as bag shape, I envision a standardized circular cross section perhaps 8 feet in diameter with a selection of bags of various lengths, weights, pressures and diameters which could be joined together with Velcro to form sausage-shaped components (rows) that could be placed across the end of the track. Multiple rows could be used and this would allow for progressively greater pressures in the back rows to control deceleration. When a car encountered the front row, it would deform into the second row and both of them would deform into the third row and so on. It might be possible to tether them to the walls at the edges of the sand traps or just let them move with the car to further dissipate energy. With a free standing system, the mass of the bags would provide some cushioning effect due to inertia.

Various setups could be tried to see what works best. It might be found that placing them in rows across the track would work better. Perhaps placing a few rows crosswise backed up by rows running the same direction as the track would work better.

To transport the whole system around, it could be designed to fit into a semi-trailer that would also carry the tethering system (if any), air compressor, air lines, a small fork lift as well as extra bags and supplies to all the races on the schedule.

After spending a little time on Google Earth, I have a selection of aerial views of the sand trap areas at all of the NHRA national event tracks and it appears that this system would fit in every one of them. I don’t know if this would work or not but the net system in use certainly seems to have its share of problems.

What say you?

 

Da bags

You know its funny to how god gives people ideas! I for one think that is a great idea. I guess my only thought is about the recoil factor. could it rebound and bounce you into belavia?

 

We are working with a sponsor,that is in the industrial netting industry.They have a R&D lab and understand this issue,they are or were involved in vehicle barriers.If anyone has any ideas please let me know as any input will be appreciated in this.
Thanks Rick
www.rickmacedoracing.com

 

barriers

How is it an F1 car can slam full speed into a bunch of stacked tires and the driver walks away? Tires are a bit primitive to what's in place now on the dragstrips in my opinion. Maybe Bernie and company knows something we don't. Just my 2 cents. The loss of drivers is taking it's toll on everyone!

Glenn

 

Another alternative

Ok, I want to put my word out there on what I think is going on.

My solution is to make the racetracks longer (TF 1320 racing is back …Next lets put make a funnel shaped barrier at the end of the track with the same energy absorbing foam blocks that NASCAR, INDI and F1 use! New Sand/rocks! Airbags! These are great ideas but personally think it has to do with money. We all know that there is a fine line between safety and money and the big question is, what is more important? It is sad to admit but $ is always the winner. I fell terrible about admitting it, but we all know deep down its true. This explains why when you read the post on competitionplus.com about how John Forces girls have the safety equipment already installed = $. I think if all the racers would have the extra money they would have already installed it.

I have been involved with racing and aerospace for many years. The sad correlation between them both is that nothing changes without a death. I call it “Blood Priority”. The reasoning behind this is nothing happens until someone dies. Another downside is it makes people think (short-term) fix and forget. Same reason a stoplight is not instaled in until someone gets killed. I think the real solution is simple, MONEY, but in reality lets develop something that would work (long-term).

My idea (if funds are not an issue) is to install the same thing that fighter aircraft have been using for years. It is called an Arresting Cable and Arresting Hook. (In layman terms) This cable is hooked to two large springs that spread from side to side of the runway. This allows the aircrafts-arresting hook to catch the cable and slowly come to a stop (within 50-100 ft). I ask, why can’t we develop a similar system that works on racecars? I feel that this system would save lives and equipment.

This is how I think the system should be installed:
The rope should be installed 1.5in above ground (NHRA min 2 in body clearance)

The hook should be installed one of two ways.
- First option: The hook would be installed at .5 in above the ground just behind the driver’s compartment and or at the rear end. The hook would catch the cable and stop the car. The only downside is if the car was bouncing then the possibility the car could jump the cable.
- Second option: The hook would be installed at the rear of the car near the wheelie bar. This hook would be attached to an air/hydraulic ram. This ram once deployed (automatically with the shoots) it would press the hook onto the pavement and catch the cable. This system would need to be designed so the pressure of the ram and material would not damage the racing surface.

I think that if this system is good for a multimillion-dollar aircraft and is proven on a daily basis it should be good enough for a racecar application.

I think if NHRA would use its resources to tap into the intellects of the people that race and work for them this system could be implemented at low cost and in short amount of time.

Please respond with thought and your ideas.

Google "F-16 arresting cable" or "gear" and or "hook" and you can find good pictures on what i am talking about.

Ralph “Phill” Perea III

 

i was in the AIR FORCE and on base we had the cable that once cable was hooked then a engine would fire up and try to real cable back in as plane was realing it out..also after the cable there was a net that would pop up to catch plane if missed hook cable or or coming in to fast for cable to stop alone....as you said..if the hooks could be set up to drop with chute then shouldn't be any missed cables..the engines for cable retracking was all under ground so nothing above ground to hit with plane..

 

I like the airbag idea - a lot. It certainly could help in lieu of the barrels.
The restraining cable idea works for aircraft that land with the wheels in front of the cable. It might cause problems for both cars in a pairing as they would have to drive over it, at speed, before the lowered arresting hook at the rear of the car would engage the , now vibrating, cable. Ask a sailor what happens when a cable breaks. They do.
Want to stand a dragster on end? The front end? Put the cable hook ahead of the wheels.
Reminds me of an old Maxwell Smart line, "It'll never work, but it's certainly worth a try!"
Cheers,
Ed

 

Net Control

They make braking systems for cables, been Googling, patent search etc... there's a ton of them out there.

I was thinking of a drum brake system with counter weights to "energize" the brake pads. When the net is hit it starts unwinding the spool/capstan which spins the counterweights clamping the brakes in place. The faster you hit the net the more braking you get. Smaller lighter impact less braking. Then after pulling car from sand you rewind (hand crank or a small winch) reapply tension to set the "Net" again.

Lots of people have simular ideas on this all over the web. I'm sure if NHRA goes this direction they will hire the appropriate Engineering Firm to develop it.
__________________

 

The amount of kinetic energy to be dissipated in a worse case scenario is immense so whatever is used needs to be able to deal with it:

KE = 1/2M x v squared
KE = kinetic energy in joules
M = Mass of the car in kilograms
v = velocity

For mass, I'm using 2,500 pounds (1,136 kilograms)
For velocity, I'm using 330 mph (147.5 meters per second)

With these numbers, kinetic energy to be dissipated to full stop would be 12,357,550 joules

1 joule = .7375621 foot pounds so the kinetic energy to be dissipated to get to a full stop would be 9,114,460 ft lbs.

Most of the sandtrap areas at the NHRA tracks seem to be at least 150 feet long so that might be a good distance to use in calculations.

But right now, I have to head to Sarasota . . . . . .

 

I was surfing around on You Tube and came across a very interesting video. This was shot in 1984 at the NHRA Spring Nationals. As we all know, the track is ultra short but the thing I found most interesting is the fact that the catch nets are basically the same as what is still being used today.

I know many of you have discussed some great alternatives but I thought I would share this video in hopes of continuing the bran storming on this topic.

http://www.youtube.com/watch?v=EodMCoeiC-M&feature=related

 

I was thinking a secondary teather that goes through the attachment loop on the chute and around the rear end.

 

Safety

The catch nets used are not the problem, I see the problem that the nets are anchored to objects that cannot move and absorb energy and therefore cause unnecessary damage and injury.
I made a suggestion to Willowbank Raceway over a year ago to set up on the far side of the gravel traps a series of three nets is sequence. Each net would be attached via a strong compression spring to one end of a pair of three ton concrete retainers. As the vehicle entered the nets at speed the initial impact would be relatively soft as the springs initially compressed and then once that was done the energy would be used to turn the concrete side walls around and eventually start to drag them behind the car. Then it would enter the second net and the process would repeat finally into the third net. By this time the car is attempting to pull 18 tons of concrete and would have been brought to a rapid but not immediate halt. I drew it all up and gave it to Willowbank and they are considering it. I would put it up here but can’t attach a photo.
Now the second opportunity is that once the car enters the net area you know where the car is and there is a great likely hood that it is on fire. If you know where the cars is located it would be prudent to engage fire pumps once the first block was moved flooding the area just in case there was a fire. I watched my friend Al Dapozzo die in a funny car fire and for a long time I have wanted to do something about how all that happened. So far this is what I have.
If you are interested send me an email and I will email the sketch to you. ken@kenlowe.com.au

 

I should point out that in order to make these 3 ton concrete side walls pivot correctly that they should be sitting on a concrete slab that was installed at a 5 degree angle sloping down into the gravel trap.
Some of the features of this system is the simplicity of the system and lack of expense necessary to implement this package, the ease of resetting the package once it has been used by just getting a fork lift to reset the blocks and install some new nets.

 

Watch this

http://www.youtube.com/watch?v=heiYovdw5Ws

Look at 5:38 Tony Pedragon is the sand, what this sand is seem to work very well. I realise that this is a low speed but the length of the sand seems to help.

 

Does SFI set the minimum safety standards at NHRA tracks?
No, I didnt think so....
Well who does???
Oh I see... isn't kinda like fox guard the hen house?
Ya that's what I thought.

 

we were there racing that day that Al had his fire. sad day something you never forget. keep up the good work.

 

Safety net arresting system

Since the accident that took Scott Kallita I have been working on a design for an arresting system that could be easily and affordably installed at any track. I now have the design completed, all that's left is figuring out who to present it to for implementation and financing to go into construction. As already been mentioned in this thread my design consists of a drum on each side of the sand trap that the net gets wrapped around, the drum sits on a set of friction plates, the braking (arresting) tension is adjusted by tightening or loosening spring loaded bolts on the top retaining flange. The design is more complex than I'll try to explain here, but as I am a contractor, I have put some time into calculating construction and installation costs, I could build and install this system in less than a month, for less than one of the new carbon fiber funny car bodies that get destroyed every weekend on tv. I have spoken to one top fuel team already, and would gladly discuss with any one who is serious about stopping these sensless tragedies within our sport. Thank you for the space.