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I see that the rubber seal / plug that is stuck into the pin end of the housing blows out in the videos… I knew there had to be some kind of reduced orifice to create a sealing effect of some kind to allow pressure to build, but was not expecting a rubber cork lol… I wonder how consistent the rubber is size wise (shrinkage and all given it is a press fit that is keeping it in place), I imagine the housings are pretty consistent. How does the rubber react to extreme hot and cold? Does it get hard when it is cold making it harder to pull the pins past it? Like you said Lee, once the pressure is gone that’s it, if the plug blows out before the pins are extracted in a hard pull situation, (where the cylinder pressure would build up higher than if the pins moved easer,) then that’s it. However to be fair, lets consider the same failure mode with a cutter, in where it activated but did not cut the loop. With the rip cord, in theory, it appears that should the power assist fail to extract the pin(s), the jumper can still pull the handle and manually extract them to initiate pack opening, where with a pinched cutter, the reserve has the potential to be locked in the container depending on where the cutter is located (above or bellow the reserve). I believe it is this failure mode distinction that John is trying to achieve, and the proof of concepts he and Karel have made shows promise. I know I am busting Johns balls here, and that is because he is promoting for sale as it is seen in the videos, and we appear to be in agreement that what is shown is not ready for production, in our opinion of course. Sometimes creative people get tunnel vision, and a challenging voice can create a moment of pause for the creator. Personally I do not mind being challenged, in fact I count on my team to do just that, and if I could not address the concerns pointed out, then I would need to take a step back and find out why. Challenging the idea is a critical part of good product development, and even is done in the educational system as part of the processes for higher level degrees. I have spoken to Karel many times, and he knows me as a calm and level headed thinker that often sees things from different perspectives, but I have not had as much contact with John, so I hope he knows as much as I am challenging him, it is to push him to achieve a higher level with it, and not to settle for something made from a bunch of parts lying around the shop… That’s fine if we are stuck on the island lol. Personally I do not have a dog in the race. I only play with Government jumpers and given the testing that it takes to get a new pyro device, let alone a life saving device, approved, I don’t see this being a problem for me if there is any thoughts like that given my challenges, shall we say, to what I have seen on the videos, and my limited experience with pyro units.. Even if it remains at this level of development, it is the market and the manufacturers that will make or brake it. Details like “can I still take my rig as a care-on when I go to Florida?” or “can I take it on an air plane at all?” That will be very important to be able to answer with documentation from the airlines that identify this specific device as being approved to carry-on or check.

I can get behind the one in the second video for sure, I have seen the patent for that long ago. Personally I can see gasses expelling out of the pin end of the housing when the plug seal is blown off, but that is just me I guess... Glad to hear that you have addressed the ATF as that could get you into trouble quick lol.. How about the Air lines?? Keep posting information, It will be interesting to see how this turns out in the long run..

I agree it is interesting and don’t mean to sound like I am dismissing it’s potential, I just see some issues with this stage of development. Like everything new, the proof is in the pudding so to speak.. lol Classification is everything with explosives.. The Red ATF book I have has many classifications of explosives and end uses for them. Every explosive substance that is sold is tracked and traced so the ATF can audit the sellers to see if there is one person who is buying large quantizes of what ever, and they may choose to pay them a visit which could be a problem deepening on the circumstances.. In any case, the difference between legal and not, is enforcement of any pertinent laws.. But that is a totally different subject to argue about LOL.. I only mentioned it because it could be a different deal than just ordering a new cutter.. A CO2 operated demo on a table is totally different than a full power test for sure.. I am eager to see more video and pull force and dwell numbers, while watching gas discharge at both ends of the housing. That is where the high speed thermal camera would make a really narly video! lol Edit: I also am very interested to hear what the other container and AAD manufacturers think of the information that is available and if they will bless it..

In a cutter the expanded gasses are contained with in the cutter.... No hot gases escape... it is a contained explosive device, and that is why air lines allow them to be brought on a airliner. This device has a cylinder that is not sealed the pin end, and the piston, (the swaged ball on the cable) is expelled from the cylinder during operation… So not only are there hot gasses escaping out the pin end (under great pressure), prior to the piston expulsion, once the piston is expelled from the cylinder, the remaining pressure charge (of hot gasses and any residual burring charge) will be vented out the handle end of the housing, (where the jumper’s hand will be if they are pulling the handle). If you look at you second video, you will see the CO2 blowing out the handle end of the housing, and that is at a much lower pressure then the pyro charge will be. Friday, I was testing a firing circuit for a new AAD I am designing, and fired two cutters right on the bench, no gasses expelled, only a click of the piston hitting the end of the cylinder. My partner picked up one cutter and mentioned that it was hot, I said yes it is, it has the gasses from a pyro charge “trapped inside it”.. In order to generate the 80-120 lbs of pull mentioned in a previous post, the pressure required to do so will be way higher than the CO2 cartridge’s charge used in the demo that spit CO2 out the handle end. I assume your cylinder ID is around .250 inches (so lets call the piston dia .250), and the rip cord cable I have here is about .090 inches in dia… The area for a .250 dia is .0490873 sqin, and the area for .090 dia is .0063617 sqin… now to get the piston area, we have to subtract the cable area from the cylinder area, so, .0490873-.0063617= .0427256 sqin of piston area for the gasses to push against… Now that we know that, we can determine the amount of gas pressure required to generate any given pull force…. So to generate 100 lbs of pull, we have to divide 100 lbs by the surface area of the piston, (how many sqin there are to push against), .0427256 sqin, which = 2340.5172 PSI. This means that it will take 2340 PSI of gas pressure pushing on the piston area to generate 100 lbs of pull on the rip cord. Given that the pin end of the rip cord end of the cylinder is not sealed, there will be hot gasses expelling out of it like a rocket motor at 2000+ PSI, additionally, once the piston is expelled from the cylinder, the remaining pressure will blow out the handle end, right where your hand will be. This is not a contained explosive device, as the gasses are vented to the atmosphere at a high volume by design. Yes, cutters will be hot to the touch after activation, but they are not a blow torch blowing hot and burning gasses directly on a jumper’s hand. Plus, given the high leakage rate of the cylinder design, and the need to sustain a high rate of pull force through the entire pin length, (+ a little extra to get it moving and some reserve for the end), the amount of gasses volume that will need to be generated and vented will be more than a traditional cutter. It will be interesting to see the pull force curves when you get to that point. Further, given that the replacement pyro gas generators are not assembled in an assembly that contains the gasses that are generated when the pyro is activated, it is an open explosive, and anyone receiving, handling, or storing, such a device is required to have an explosives handling and storage license from the ATF, and a properly rated magazine to store such charges. I know this because I am going through the process to get a license right now. Technically, it is illegal to send an open gas generator (explosive device) to anyone (individual or business) that does not have the proper ATF license and storage capabilities. This means when a jumper needs a replacement gas generator, they, or their rigger, will be required to have a explosives handing and storage license, as well as the other required safety equipment required by the ATF to handle open explosives, in order for a new gas generator be to shipped to them. The ATF is really sensitive to explosives being shipped around lol. The concept is interesting, but needs more refinement, as in contain the hot burning gasses with in the housing so no one gets burned, or their nylon container, and or, jump suit doesn’t get set on fire when they are at 1000 Ft AGL with lots of wind to feed the flames.. At best they should hope for a burnt hand… CO2 and compressed air are one thing, explosive generated gasses are totally different.. Perhaps a video of a rigged system, with pull force instrumentation to measure the force generated and the time to pack opening from activation would be next. Make sure to have both ends of the rip cord housing in the camera frame so we can watch the hot gasses blowing out the ends of the housing. I know you do not like cutters, and I do think that this is an interesting approach to an alternative activation method, but as I said, it needs to be refined more before it sees the market…

I think the next video should be made using a high speed thermal imaging camera, looking at each end of the housing when the pyro fires!! That would be narley! lol Just a couple of thoughts that I am sure have been thought of; Will you be sending Nomex gloves with these as well in case the jumper is pulling the handle when it fires?… I’m sure airlines will love the open explosive arrangement as well Very interesting though...

I think you misunderstood my intentions.. Although at one time I was considering taking on the Argus, I decided long ago to pass on the opportunity. Then it was requested that I make a cutter for the Argus units currently in the field.... It is this scenario that this thread pertains to, not the controller... If I had produced a cutter for the Argus, and someone goes in because the controller did not fire, as long as the cutter works as it should, I’m good in the long run as long as my component operated as specified. I have chosen not to even take on that opportunity as well... So it is still up for grabs should someone want to take it up... Something I learned long ago is you get what you pay for lol.... lawsuits are best when they are avoided.. Seriously speaking.... we did receive a good amount of positive feed back at PIA when we were considering only making a cutter. There are still units that are in the air currently, and of the fatalities of late, none had an Argus. I forgot how many are in air per the service records, but they are still out there, and we have not heard anything about them witch is a good sign IMOP. If you are serious about following through, contact me and I can get you in touch with the right guy at Aviacom, but be for warned, he will not approve of a Cypres or Vigil cutter lol...

I have seen that kind of thing before. Generally the idea is to have a bar, or sometimes a pad, as a contact surface instead of the aneroid. In this particular instance I can not say... I don’t use such a thing in my altimeters. Quality, most of the time, is in what you can't see...

That is unfortunate.. Many PIAs ago I contacted Viplo in regards to being a USA service center, but I never heard back from them.. As for a shop that would at least have the required equipment, you would need to find an aircraft altimeter repair shop, or maybe a barometer repair shop, but I seriously doubt any one would touch a skydiving altimeter. Just a note: Even my warranty does not cover an altimeter that was dropped or hit against something. Altimeters are precision instruments, and have to be cared for as such. As a reference, never hit a mechanical altimeter harder than you would a fresh egg… Hopefully you did not pay much for it. When buying gear, it is always a good idea to check the customer service history before you buy..

Free Fall Accessories here, I must apologize for not getting back with you after I received your e-mail. There never seems to be enough time in a day, or memory in my brain lol... We only work on Gov AADs, (military US and Foreign, Forest Service, and BLM).. No civilian AAD product. We have developed electromechanical pin pullers that have been used on sub-orbital rockets, and strictly mechanical timers for Forest Service Smoke Jumper Equipment Bundles... We have developed a Parachute Flight Data Recorder for the US Forest Service Smoke Jumpers, and are currently working on an AAD for Military Static Line Jumpers. If any of this is of interest to you, let me know. Free time is limited, but I will make an effort to provide you with what we can. Regards..

Thems fighten words lol... Many arguments have been started over the interpretation of the language regarding AADs, TSOs, and the container manufacturers... I for one am staying out of it! LOL Personally I would not want to take on the liability of a product that was manufactured by another company, (and identified as not airworthy by that company), by claming that X tests, supersede the OM's expiration date.. But that's just me Sounds like an expensive international exercise for such a little market to generate revenue from... kinda supports what I said about being an expensive pain lol.. YAAAHH... NOOO... LOL But feel free to run with that idea

You will need to send it to a repair facility, or at least a metrology repair facility that has an altitude chamber with reference gauges... Unfortunately this is not the sort of thing one repairs at home... I have recalibrated a couple FT-50s in the past for good friends, they are straight forward movements for someone with experience with this type of instrument...

Personally I do not like the Cypres cutter because the long plastic tail is easy to brake. Granted there are thousands of them in use, it is just something that I don't care for. Also I do not think that a rigger can install an AAD with parts not approved by the AAD manufacturer, but I may be wrong about that.. ( an Argus with a Cypres cutter for example).. The Cypres cutters have an expiration date as well, so if the manufacturer says that they are not airworthy, how would one convince the Feds to allow them to be used past that date?... Plus I bet that Airtec would likely per sew legal action to stop their cutters from being used with other AADs, not sure if they have a legal standing, but that would not stop them from being an expensive pain... If I were them, my concern would not be a computation one, but rather a reputation concern, as lets say a jumper goes in with a non Airtec AAD adapted with an Airtec cutter... The AAD manufacturer would say the cutter failed, the cutter manufacturer (Airtec) would then have to deal with that, even though they did not have anything to do with it at all... Then again, I could be wrong..lol

I am using a 6 pin M-8 connector for mine... I will not be offering any non military /gov AADs or cutters.. If you are interested.. I would encourage you to talk to Aviacom about their situation...If you haven’t already.. My power cartridge supplier will not have anything to do with a company that supplies civilian AAD cutters, and I am not excited about the lawsuit nature of the sport market... Looks like you have made some progress with you pin puller... Are you planning on building an AAD to go with it?

I wanted to up date the information as to not leave an open ended hole... I have been in extensive talks with the power cartridge manufacturer that we are using for our military AADs. The subject of the conversations has been how to guarantee that their product will not be used in non-military applications if we are supplying a sport market cutter. Based on the significant capitol investment that would be required to get all the container manufacturers approval, and the very limited remaining Argus market, I had decided not to peruse the effort of producing a replacement cutter for the Argus AAD earlier this summer. And to further solidify my position, our supplier said strait out that they were not interested in exposing themselves to any liability, directly or indirectly, from any non-military product that we, or a subsidiary, may market. In other words if we offered a sport cutter, they would not supply us with power cartridges for our military cutters. So unfortunately we will not be offering a sport version of our cutter, for any sport application.

Many thanks... Although initially confusing, the letter that was posted towards the end of the thread states that two individuals lost track of altitude and both their Argus AADs fired deploying their reserves, I assume they landed with out incident given they acknowledged that they lost track of altitude.

Does anyone have any knowledge of an Argus double save in Hungary? I heard some whispering, and I am very curious as to the details. Any information would be appreciated thanks..

If you take a close look at your hand while in free fall you will notice that the digital altimeter is not seeing any air at all, where as the analog altimeter is getting some given it's slight angle, ( I do not recall if the vent on that is on the top or the bottom on that altimeter). I wear two analog altimeters on one arm, a wrist mounted and a hand mounted, along with a chest mounted one, (I make them and am still cycling the original prototypes for grins). Depending on where the wrist mount one is clocked on my wrist compared to the hand mounted one, I can make the readings vary by as much as 1K if I put the wrist one in the some air and have my hand flat blocking the other one. Now comparing a digital pressure transducer with possible temperature compensating software trying to keep up with the fast changes things can get interesting... Altimeters need to be checked in a controlled environment, and a jump is not a controlled environment lol...

I would hope that the information is some where, if not, that is a good reason for the Feds to take over incident investigations. Additionally, having persons that make up PIA who may have a financial interest in the manufacturing or servicing of any product that could be involved in an incident, participating in the documentation of that incident, is just asking for questions about a cover up, and other thoughts. I am not saying that is what is going on, but there have been enough of these AAD fires and or reserve situations to be able to find commonalities. As to another post about the idea that the Cypres may fire too low... Do not let your opinion of an author affect any information they publish. Let the information stand for its self, any factual information does not become any less factual just because one does not like the author who published it. If we had the incident information, that could be used to validate or debunk any claims about a particular product, but we do not have access to that information, and that puts into question many things. I have a doc that was sent to me of all the SBs for one particular product. The report is comprised of all the SBs from the manufacturer, along with some comments from the author drawing some conclusions based on their point of view. Regardless of whether one respects the author or not, the referenced documentation was generated by the manufacturer, and is therefore factual and beyond argument. Self regulation only works if we actually take care of business. I for see Fed involvement in our future at this rate, and I can not argue that we are better off on our own, given how little is known about incidents that have killed people in the double digit numbers!

I am not able to put together a string of words that adequately reflects my feelings if it is correct that the incident reports do not have the "equipped" gear listed, last repack date, Last AAD service, etc.... What is there to investigate if there is not a record of what happened.... Some one please tell me that there are detailed records kept after an incident in an effort to prevent another jumper from dieing when their equipment failed them after (presumably) being activated with in an acceptable altitude.

Some where there should be a collection of incident reports for all the instances where the reserve failed to deploy in time after an AAD fired. These reports should indicate the container and reserve combination, and which AAD it had. I would only focus on rigs with an AAD because that will provide as known of a pack opening altitude as possible, as who knows when a jumper with out an AAD pulled the reserve rip cord. If all the rigs had the same AAD in them, then the “actual” activation altitude would need to be looked at, not the altitude that “the AAD thought it was at”. Now the AAD manufacturers will point to the containers, and that would be supported if there were different AADs used…SO… If the rigs had different AADs in them, then not only do we need to verify that the AADs are firing at the proper AGL altitude, but additionally, were the reserve “systems” of those rigs capable of operating according to the TSO that they were issued under.

The Cypres was born as the result of a reserve pin being bent to the point were it could not be extracted, and a fatality resulted. By design, opening the container by means of severing the closeting loop provided a secondary method of pack opening that did not use the pin. There are several different methods that have been patented to sever the closing loop over the years, but the cutters are used for other applications and were small and available. I am talking with John Sherman about developing a pin pusher that he wants. Perhaps that will end up replacing the cutters, but personally I like having a separate method of pack opening should the pin brake or be damaged. Each person will have their own preference.

Your theory makes logical sense but I would be interested to see actual tests conducted so the differences (if any) could be documented. If I remember correctly, cutters were located bellow the free bag as a standard practice, but there was a 4 way that went low and all their AADs fired, but none of their reserve containers opened at all. It was attributed to a long closing lop that zigzagged back and forth, and possibly less spring force from the loop being long. The result was some manufacturers tested different cutter locations to try to prevent that from happening with their containers, hence cutters are in several different places depending on the container. There is a cutter / container compatibility test that the manufacturers use to evaluate the time from cutter activation to container opening. However it does not take into consideration the pack job ageing over the 180 day cycle.

This is the kind of feed back I was hopeing for. This was just an idea that popped up in my head and I thought I would put it out there to see if others come up with the same drawbacks as I did, or pointed out advantages that I did not think of. I like being able to talk about ideas openly, I think it gets people thinking about how their gear works and may learn something they did not know. We are all in this together, when any gear fails a jumper, it affects us all. I have many legal pads full of good ideas at the time, which after time thinking about it, were abandoned... This is the creative process...

John Sherman is very pro pin pusher, and I may be making some prototypes for him to play with. Personally I like the idea of just using the pin, but in the same breath I remember when the pins were braking and the thought of that makes me break out in a cold sweat, so I as much as I like the pin puller or pusher idea, I am more for a totally separate method of pack opening as a back up. Each person will have their own preference, and I think it is good to look at everything as everything has pros and cons to it, as well as things to be learned from development efforts.

Yes, that has happened. That is why it is so critical to have a cutter that is designed for use in a reserve container and to cut the closing loop material. It is impressive to see a cutter cut a cable, but I have dikes that will cut cable very nicely, but will not cut 300 lb Spectra to save your life. Your comment on choose of gear by design is why I think it is critical to completely understand how a container works, and the difference between the different containers prior to buying one. More that not a decision is made because of how a particular container looks, or an instructor has one, which is fine as long as you know how it will work with an AAD for instance, as the instructor may not have one in his rig so the location of the cutter didn’t factor into his decision. I had the benefit of being able to watch the DZ rigger repack reserves at the end of the day, and that allowed me to see the differences in design, how AADs were installed.