SundayDriver

[quote]Originally posted by gbaker:
<strong>I have $1,000 that says I can get out of any Isaac system in less than a second.</strong><hr></blockquote>

Gregg,

Why don't you help us understand the system instead of trying to make some lame bet. I think I was clear that I do not fully understand how it works and have concerns.

I take it you either use it or work with ISAAC. Are you willing to be helpful or do you just want to place bets?

SundayDriver

[quote]Originally posted by gbaker:
<strong>I have $1,000 that says I can get out of any Isaac system in less than a second.</strong><hr></blockquote>

This is really interesting. I just checked out your profile and see that you work for Isaac. I would think that you could contribute quite a bit to this discussion and would rather address the questions with facts and test data. We are trying to be open minded and are having an open discussion here - how about some positve contribution that would present your product and your company in a positive light.

924RACR

We have been having a long discussion about this system for months on improvedtouring.com...

I agree that there are damping characteristics in any webbing system, HANS or Hutchens, but even with the HANS you must reach the end of the tethers first. As I understand, when properly adjusted there should only be about 1" of slack in the tethers on a HANS, minimizing the time for acceleration. OTOH, it's at a limitation of free motion. Then again, even with the ISAAC device you still aren't completely free to move, there's still some degree of motion limit. For me, in this regard, cost is more of a deciding factor anyway.

Yes, I do race a cheap Porsche, not a more expensive one; I do my best to keep my costs down, but OTOH I do my best to make sure that I do have adequate safety equipment before I hit the track. I do wear 3 layers of Nomex (2layer suit plus underwear, more than most), and have a full 11lb fire system, not a 5-lb or handheld. These should combine to give me time to deal with any restraint system as required.

I do agree the pins are probably the weakest point of the design WRT exit time, but think that practice (which will be enevitable once you start using the device) should minimize the impact, no more than remembering to remove the steering wheel. I've had my moments, honestly, when I've forgotten to remove the wheel - like after my first win, and my mind is gone - but I'm reminded pretty quickly that it's in the way! Likewise here, I feel. Personally, I've found myself in much better mental state after being hit than after winning a race! LOL

gbaker

[quote]Originally posted by Mark D - TT Alumni:
<strong>

Gregg,

Why don't you help us understand the system instead of trying to make some lame bet. I think I was clear that I do not fully understand how it works and have concerns.

I take it you either use it or work with ISAAC. Are you willing to be helpful or do you just want to place bets?</strong><hr></blockquote>

Mark,

I apologize for being short. It was inconsiderate and tasteless. We are tight on time here with Sebring this weekend and SAE/PRI next week, so I couldn't afford to spend much time on long discussions.

However, I have made this bed and now must lay in it:

1. Everyone who has used an Isaac system, myself included (SCCA-SRF), says that getting out is no problem.

2. The belt mount "rolls" under the belt. During a crash it follows the body as the shocks react.

3. Racers are going to have to get their mind around a new concept in understanding the role of the shocks. As an engineer, this should be easy for you. For at least two years now (post Earnhardt) everyone has thought about controlling head loads by controlling the position of the head with a tether connected to something. Once the slack is taken out of the tethers, they create a reaction load which works to offset the impact load. Basically, the difference between these two loads is the net load on the head.

This works fine if the tethers are short and stiff enough. The longer the tether, the more time for the head to gain velocity (accumulating kinetic energy) before the tether reaction begins.

Shocks, however, will generate a reaction based on velocity, not position (shock reaction = damping coefficient x velocity). So, shocks do not wait for the head to reach a certain position before they react. The reaction begins the INSTANT the velocity spikes up, regardless of head position.

For details on the theory behind and development of the Isaac system, go to <a href="http://www.sae.org" target="_blank">www.sae.org</a> and search for technical paper number 3306, which will be presented Monday at the SAE Motorsports Engineering Conference in Indianapolis.

SundayDriver

Gregg,

Thanks for the info.

I agree that the dampers are a good idea. They should better control decel rate. Even when fully extended, in a secondary impact they would behave no worse than a tether.

I might have been willing to take your word about exit speed until you said you drive SRF. I know you have to be completely nuts to drive those things (Yes, I drive SRF also.)

I will get the paper as I am very interested in how the device behaves and am still wondering about where the slider ends up. Like I said, others have had some issues with the strap type devices. It would be good to have other devices that are proven effective.

Mark

gbaker

[quote]Originally posted by Mark D - TT Alumni:
<strong>Gregg,

Thanks for the info.

I agree that the dampers are a good idea. They should better control decel rate. Even when fully extended, in a secondary impact they would behave no worse than a tether.

I might have been willing to take your word about exit speed until you said you drive SRF. I know you have to be completely nuts to drive those things (Yes, I drive SRF also.)</strong><hr></blockquote>

Now that's funny.

[quote]<strong>I will get the paper as I am very interested in how the device behaves and am still wondering about where the slider ends up. Like I said, others have had some issues with the strap type devices. It would be good to have other devices that are proven effective.

Mark</strong><hr></blockquote>

The belt connector ends up just rear of the top of the shoulder.

Strap-type systems must be worn extremely tightly to work well. Most people wear them loosely.

Your HANS works very well. All products help, but all can contribute to secondary injuries. Sort of like, "You saved my life 50 milliseconds ago, but what have you done for me lately?"

Sloth

Perhaps some clarification on the concern I am expressing. I am sure that the driver could quickly pull the pins to release themselves if they had to. That is not necessarily the issue that I would be concerned with.

Not all racing/DE accidents result in a driver walking away from the accident. If the car was on fire, upside down, with the driver passed out... it would take longer than a second for the corner/emergency workers to release the those pins to free the driver. I know that would be a worse case scenario, but something to consider in a situation when seconds do count.

addictionms

Having a HANS device, I am probably biased, but I do wonder about how easy it will be to hook up during driver changes in a race.

I know that is one of the advantages of the systems that was attached to the driver or held in place by the harness.

It is a small number of drivers that actually need this capability, but since I try to drive in as many enduros as possible, it was an important factor in my decision. I also opted for the little seen quick release on the HANS so I can exit with or without the carbon fiber part.

Having said that, all of these are significantly better than nothing at all, so I say each to their own, but own one,

No doubt this technology will only get better with new ideas....

Jim

gbaker

Good points.

I want to address them with proper attention, but must now dash off to the Turkey Trot at Sebring.

SundayDriver

[quote]Originally posted by Sloth:
<strong>Perhaps some clarification on the concern I am expressing. I am sure that the driver could quickly pull the pins to release themselves if they had to. That is not necessarily the issue that I would be concerned with.

Not all racing/DE accidents result in a driver walking away from the accident. If the car was on fire, upside down, with the driver passed out... it would take longer than a second for the corner/emergency workers to release the those pins to free the driver. I know that would be a worse case scenario, but something to consider in a situation when seconds do count.</strong><hr></blockquote>

Interesting and valid points. With all the new safety equipment coming out, there are now plenty of cases where the workers have never seen this stuff.

I guess if I were using a new item that required a step to disconnect, I would take it around to the workers and let them see it and play with the release mechanisms. After a while, the workers will all be familiar with the new stuff, but I would take it on myself if you are goig to be a pioneer.

SundayDriver

[quote]Originally posted by addictionms:
<strong>Having a HANS device, I am probably biased, but I do wonder about how easy it will be to hook up during driver changes in a race.

I know that is one of the advantages of the systems that was attached to the driver or held in place by the harness.

It is a small number of drivers that actually need this capability, but since I try to drive in as many enduros as possible, it was an important factor in my decision. I also opted for the little seen quick release on the HANS so I can exit with or without the carbon fiber part.

Having said that, all of these are significantly better than nothing at all, so I say each to their own, but own one,

No doubt this technology will only get better with new ideas....

Jim</strong><hr></blockquote>

I have a different way of getting in with my HANS as I was constantly struggling to attach it in the belts, etc, etc.

I attach the lap belts and then place the HANS on my shoulders but only pull the helmet onto the crown of my head. It never gets disconnected from the shoulder part. With it sitting there, I can see everything to get the shoulder harness in place and the arm restraints. (The arm restraints were actually the hardest with the helmet on as you could not see anything and had to feel around to hook up.) After everything is latched, the helmet goes on the rest of the way, strap the helmet and tighten the shoulder belts.

You could get into the car with the HANS on and the helmet up high if you are doing an open car, or pull it up after getting in a closed car, for an enduro change.

SundayDriver

[quote]Originally posted by gbaker:
<strong>Good points.

I want to address them with proper attention, but must now dash off to the Turkey Trot at Sebring.</strong><hr></blockquote>

You guys have fun. I think I will shift my stock portfolio to Fiberglass companies.

gbaker

[quote]Originally posted by Mark D - TT Alumni:
<strong>

I think I will shift my stock portfolio to Fiberglass companies. </strong><hr></blockquote>

Spoken like a true SRF pilot.

Also, Mark, there seem to be similar themes on this thread and others I've been dragged into -- uh, I mean others in which I feel honored to have been given the opportunity in which to participate. I'm going to make an attempt to consolidate them into one mega post for all threads.

Annonymity will be maintained.

gbaker

Everyone,

There has been a flood of inquiries recently about head restraint systems in general and the Isaac system in particular. These have come principally from direct e-mails and forum postings. Although many of these questions are addressed on the FAQ page, some are new and worthy of attention. Others have been repeated so often that we feel compelled to elaborate.

The e-mail questions we will respond to directly, which is only appropriate. The forum questions are another matter. In this post we hope to respond to several themes. (Please Note: Two threads have been the source of most of these inquiries. Let’s call them Thread A and Thread B.)


Starting with, "What happened at Sebring?"

The most insightful, scientific, reaction to the Isaac system by a racer was, "It’s noisy." Just goes to prove that no product is perfect.


Second theme: "How does getting in and out of an Isaac compare to other systems?"

(From Thread B Member. Concerns about egress) "Not all racing/DE accidents result in a driver walking away from the accident. If the car was on fire, upside down, with the driver passed out... it would take longer than a second for the corner/emergency workers to release the those pins to free the driver. I know that would be a worse case scenario, but something to consider in a situation when seconds do count."

(Response by another Thread B Member) "Interesting and valid points. With all the new safety equipment coming out, there are now plenty of cases where the workers have never seen this stuff. I guess if I were using a new item that required a step to disconnect, I would take it around to the workers and let them see it and play with the release mechanisms. After a while, the workers will all be familiar with the new stuff, but I would take it on myself if you are going to be a pioneer"

(Response by cornerworker, to a similar question on Thread A) "If you have concerns about the cornerworkers not being familiar with any head and neck restraint system installed on your car/person/helmet, you are hereby invited to attend your local F&C meeting. By and large you'll find us to be a friendly bunch. Plus we're willing to learn about different devices so we can help should you need additional assistance. Just talk to your F&C chief, or show up wherever you see lots of folks in white bright, and early in the morning! "

(From a Thread B Member) "I have a different way of getting in with my HANS as I was constantly struggling to attach it in the belts, etc, etc. I attach the lap belts and then place the HANS on my shoulders but only pull the helmet onto the crown of my head. It never gets disconnected from the shoulder part. With it sitting there, I can see everything to get the shoulder harness in place and the arm restraints. (The arm restraints were actually the hardest with the helmet on as you could not see anything and had to feel around to hook up.) After everything is latched, the helmet goes on the rest of the way, strap the helmet and tighten the shoulder belts. You could get into the car with the HANS on and the helmet up high if you are doing an open car, or pull it up after getting in a closed car, for an enduro change."


And finally, direct e-mail from a thread A lurker:

"Hi to all. Just a couple of questions about your product.

First though, special thanks to [Isaac guy] for your responses on the [Thread A] website. I'm what most call a lurker - reading the site, but never posting to anything, just trying to glean as much info as possible from my fellow [Thread A] competitors.

Anyway, on with the questions. 1) There have been several posts as to the possibility of alternate release pull tabs for the Isaac, I thought you had said there were some options, and would like to know what they are….
2) I am tall and thin, - [height] and race a [car] in [class] are there any considerations I should take into account for positioning the Helmet mounts for your product, or is there a template you lay on the side of a helmet to position the tabs for drilling the mounting holes? (You probably cover that in the instructions, but I'm curious before plunking down cash)
3) You have also mentioned the possibility of future upgrades for the product, and I was wondering what those might be.

Thank you in advance for your reply. Also thanks for developing a product that can literally save our necks.

Mr. X"

Dear Mr. X,

Thank you for your message. We offer the following responses:

1) There are several versions of quick-release pins available. The standard pin, which we stock, is referred to as a push-to-release style. Two other styles are commonly available: pull-to-release and dual-action, push/pull-to-release. All the pins we use are certified aircraft grade only. They are five times more expensive than industrial grade, which we will not use.
2) Yes, this is covered in the mounting instructions. You use the mounts themselves as templates. I understand your concern, though. One guy said he was going to try the system out by crazy-gluing the mounts, before he blew holes in his $900 Kevlar helmet. Good idea, I would too. After all, who has ever heard of something called Isaac.
3) Isaac is a totally modular system (like your engine), so you can upgrade any component. One example would be the helmet connection. Everyone who has used it thinks it’s fine. Everyone who hasn’t hates it (go figure). If we come up with a better/easier one, we would make it available as a separate item. Switching some of the structural components to titanium alloy should make the system capable of withstanding an impact of around 150Gs. Also, theory suggests we could drop the head loads even further by switching to a special shock. (Do you see a high-priced "Pro" version emerging here )

Do Thread B guys know that if they post on Thread A they get a $50 discount?

MJHanna

Gregg:
At what point in time will you do lateral (side) impact testing?