New AAD made in USA

[RiggerLee 61]

If you added a good GPS antenna, some thing that could for instance be routed up along with the control head and be tacked down under the reserve cover flap could you get good enough data to cross check the pressure altimeter and test the altitude correction to it based on the accelerometer data? I mean your doing this correction which should smooth it out but you can't just test it in a void. My Javelin is old it'd got the bigger hinged reserve cover flap with room under it. I'll make it work if I can see the correlation data.

Lee

Lee
[email protected]
www.velocitysportswear.com

[RiggerLee 61]

It's not silly at all. They are doing it in cars for automobile crashes. And this shit does happen. There was an accident in here in Texas where a man died. He went in on the last jump of the day. it was actually a couple of days before they even knew that he was missing. It was hell trying to find the body.

I had a friend die at Quincy one year. Big Jerry. Quincy was a mad house with people getting on pick up loads and then landing all over and going off to pack. And then find another load. He jumped with this group but wound up landing off out side the fence. He actually landed in a nice spot between two rows of hangers. We're guessing that he had to make a turn to get in to it and miss judged it. You could see the spot where he first hit and where he skidded to a stop. With out a doubt he was hurt but the sucky thing is he didn't die right away. No one knows how long it took but he was conscious and able to undo his chest srap and loosen his leg straps and take some things off. No one could hear him call for help. Eventually some one walking through the hangers found him but by then he was dead.

I can't remember his name, but carrot top was another jumper we had trouble finding. He had a preme on his main sit flying and suffered a spinal injury. He just floated down under canopy off airport and crashed. He was down flat no one could see him. People were driving all over. There was a plane up but no one had a radio. He could see the jumper and was trying to give directions to the cars on the ground through manifest. Finely he just flew down over toms car so he could follow him and literately led him to to site. It took forever. Time is critical with spinal injuries. Swelling can be even more damaging then the original injury. Short version of the story is that he's paralyzed.

Students land off all the time. I've seen students lost for hours. Just dissipear in to tall pine woods on the last load of the day. Then every one is out after dark trying to find the student. If one were injured it could have been really bad.

An impact activated cell phone ELT built into a rig would not be a bad thing. That's how the ETL's in airplanes work. It's got a weight in a little lever switch. No shit, just that simple.

Lee

Lee
[email protected]
www.velocitysportswear.com

[Hellis 0]

In my opinion the SMS/GPS thing does not need to have anything with the AAD.

Imagine you set up four corners of the field you jump at, if your phone detects you are within these corners, all good.
But if you are outside of them and below 300 ft (no chance to land on the DZ) then it sends the SMS.
This means it only helps if you have a parachute, not for terminal speeds, but then again the phone won't work anyways at terminal.

I see no reason to "wait for an impact" before sending an SMS for hemp.

[df8m1 19]

Hellis

In my opinion the SMS/GPS thing does not need to have anything with the AAD.

Imagine you set up four corners of the field you jump at, if your phone detects you are within these corners, all good.
But if you are outside of them and below 300 ft (no chance to land on the DZ) then it sends the SMS.
This means it only helps if you have a parachute, not for terminal speeds, but then again the phone won't work anyways at terminal.

I see no reason to "wait for an impact" before sending an SMS for hemp.

It was just a conceptual thought I had and I agree with you that and AAD has only one job so don't worrie about being able to sink it to I-tunes lol...

This concept would be like the "I've fallen and I can't get up" thing, but on a higher level lol... I will scribble down some notes on it and put it in the folder along with the Canopy tracker lol

LEE:

I know that the GPS has to be unlocked to get the vertical speed up, but I do not remember what the speed limits are, (it has been a while since I looked into GPS), and the refresh rate, (sample rate) on GPS is usually limited considering this application, so the data could be very late to the party. If the GPS could keep up with the vertical speeds, then the slow sample rate would not be as much of a problem, but I would be concerned about basing a correction factor on a slow sample rate. I would want to have a way to validate the GPS data's accuracy during operation, as if it were to get erratic, things could get interesting in a bad way.

The reason that I have not built a flight data recorder with GPS is that every customer has tried it and found it to not be reliable. Granted I do not know what they were using for GPS data collection, so perhaps that was the problem.

Might it be worth playing with a GPS recorder specifically made for us to compare the AAD data to?? In a prefect world absolutely, but the GPS systems that are already available are for military parachute navigation, or cargo navigation which is slow in movement, and allows for a good amount of error between data points, (there is more time to average and correct for error prior to needing the next data point.)

I would lean more to a laser or radar measurement system for a comparative altitude measurement value to validate the AADs altimeter. You mentioned a radar system previously and I assumed it worked fairly well at speeds higher then the average jumper.

Thank you for your offer to help. I have received several such offers privately but unfortunately I accidentally deleted my PM mail box so I lost all of them. The trick will be to get a waver from the manufacturers to allow a rigger to pack the box into the reserve container. I have a Vector and 2 Infinities, I have not contacted Infinity and have not heard back for UPT yet, I will call next week and see what it takes to stay within the spirit if the “accordance to the manufacturers recommendations” or however it is worded, so my rigger is legal when he seals the container with this thing in it.

Rest assured, we will reach out for third party efforts when we reach that phase.

[df8m1 19]

Sorry for the multiple posts.. I forgot to mention something else I wanted to lol..

This thought is in regards to the AAD as I see it. I was PMed by a jumper wanting to clarify the circumstances in which I claim this AAD would not fire in an aircraft. I must confess that when I say that I am thinking of “pilot in control” conditions where the pilot has control of the aircraft, but this message was about a situation were the pilot did not have control of the plane and it hit me really just how important it is that any AAD should not fire inside the aircraft under any circumstances.

I mentioned it to my associate and he pointed out that turbine aircraft can rocket up to the arming altitude of the AADs available today and then have a problem that causes them to come down fast, fast enough to cause AADs to fire. Given that some DZs take off with the door open, or if the jumpers in the back get the door open as the plane is going down, then an AAD or multiple AADs going off could make a bad situation that might be manageable for the pilot, into one that is tragic.

I think it is very important that an AAD not fire when it is in an aircraft, regardless of altitude and descent rate, or regardless of pressurization. I keep saying to my self, with in it’s normal operation, “an AAD should do no harm”.

[3mpire 0]

Quote

What if there was a device that had GPS and a Cellular capability, and it could detect a significant impact consistent with a fatal result, after which, it would call/text a number and transmit the GPS location along with an announcement of the hard landing?

An interesting idea. It raises the question of battery life/power consumption, which you've touched on before earlier up thread.

One thing I had been thinking about but hadn't mentioned yet is whether the device would be smart enough to go into a low power mode and/or turn on/off sensors as they are needed to conserve battery power.

A GPS beacon is a more realistic example of something that would turn on when, say, it detects a landing that indicates likely severe injury or death.

While cellular might be interesting depending on the terrain you're jumping over it might not help. A jumper went in on mt si in the cascade foothills after a helo jump and its possible/likely that cellular service wouldn't have been available anyway.

What about something like radio transmitters (APRS)? I don't know what kind of energy hog it would be but perhaps a radio ping of the last known coordinates would last longer allowing for a longer window for a SAR group to locate it?

edited to add: i know that APRS loses accuracy the lower you get to the ground but if you were to have a receiver in a helo that was flying a grid it would likely be able to detect a transmission.

[yoink 321]

I've worked in software development and you're a far better engineer than I am, so you'll know where I'm coming from when I say the more functions you add to something, the more potential for unforeseen interactions there are...no matter how much testing you do.

GPS? MMS messaging?... really? THAT'S what we want from an AAD?


Please - at least make a model that just does what it's supposed to do (cut the reserve loop) with 99.999% reliability with a decent battery life and I'll buy it.
It's like me not buying a phone which has automatic sync to facebook and email. I just want to make phone calls and charge the thing as infrequently as possible. Everything else detracts from the main purpose...

[RiggerLee 61]

To be clear I was thinking about a GPS purely to give a vertical speed reference to try to look at the error correction as you try to evolve your algorithms. With out that I don't know what you could compare it to. I don't think that it's enough to just look at the graph and try to take the discontinuities out.

You know who can tell you all about vertical GPS data is Phil. Give him a call. We use a GPS as the primary guidance including altitude. There is also an INS used mostly for orientation. It can integrate the acceleration but that's got a pretty big cumulative error in it. I don't know how the old ICBM's pulled that stunt off as well as they did. We do not have any type of pressure altimeter on board. Hell it would only be good for the first 40 sec of the flight.

The units we use are unrestricted but it is has no military codes. I don't recall the exact limits of an ordinary GPS. I want to say that it was some thing like 1,000 mph and 100,000 ft? I don't think it matters if that speed is vertical or horizontal. I mean if you think about it they are used in airplanes all the time that fly faster then us. I think the only question is the vertical accuracy. Oddly enough the fancy unrestricted GPS had a shitty antenna. The one way more used actually had a much better antenna that had better signal lock on the satellites. And it was a small thing begging to sit under a top flap or on a helmet. Give Wamore a call. Those guys are cool. They'll help you. They also do their vertical stuff with GPS. It handles free fall for them with no problem. I'm not sure they're getting the high quality data you would need but they time there opening with it. And they can conture fly terrain.


The best alternative I can think of would be to mount other static sincers else where on the jumper. FXC used to have one on the front with several filtered ports that they some how averaged and got a static pressure from. This is going to sound goofy and look even sillier but I would try mounting it on the helmet. The thing is your going to need clean air. I'm actually thinking about a rod sticking up off the helmet. Remember the Ball Probe that they used on some of the old airplanes. They used it on test vehicles. The X-15 had one. It was a ball on the end of a probe. It had a number of static ports all over it and they used it to get AOA and side slid data as well as dynamic pressure. What you would need would be simpler. It would be about the size of a golf ball. Hollow with holes evenly spaced on it. The idea being to get an average of all the pressures all over the ball. The key thing being that it's symmetrical which ever way it's orientated. I would think that you could calibrate it in to an... omni directional static sencer. I've got this image of a guy with a helmet on his head with this dorky looking unicorn horn sticking out from it. The point being to try to get a clean static signal.

Putting it in a rig. I think you'll find that easier then you think. Let me help you out. None of the AAD's are approved. None of them. The manufactures wont touch the subject with a ten foot pole. It varies in the way they will state it but it generally come to some thing along the lines of, "They have absolutely know clue what that pocket is for. They don't know what those channels are for. And they make no statement at all about approving or disapproving any installation of what ever winds up in their." The Argus thing was an anomaly. People got freaked out at the idea of it pinching a loop and locking a container. This comes under the heading of interfering with the normal function of the container. That is a big no,no. Bad, bad, bad. That's where they draw the line. I would make it inert. No cutter. Or a dummy cutter like a fuse that would detect a firing event, be it commanded or uncommanded, or rout the loop out side the cutter. I don't think you'll have a problem. In fact I think they will be very supportive. Thik about it. This unit could have a much higher firing window. It would add another 180 feet to their opening time before impact. And reduce two outs. And not fire in swoops. and save wing suiters... Get the idea. And it doesn't matter how they die. The container manufacturer will always be named in the law suit. If I was them I'd be financing your testing just to reduce their own liability. I'd line test jumpers up for you.

Radar. Hmmm, sexy. I just don't know how you'd make it work in the traditional since. I mean that thing was a directional dish. I'm not sure there is such a thing as an omni directional radar? If there is I'm not sure I want it around my balls. I mean the whole point is to have a real number on your speed as you roll back and forth from your belly to your back and tumble all around. Here's a thought. It's a bit of a pain but you might be able to make it work. What about a transponder? Honestly most "Radar" isn't really radar. It sends out a ping. And the plane sends a ping back. That's how they get most of their ranging data. It takes a lot more power to get a primary return. What if you had a transponder in the peas and jumped over it. Black box sends out a beep and gets a ping back. Range. Instant accurate altitude. Russel might be able to help you. I think he was an EE specializing in antennas. Or call up the Mustang guys that did the radar altimeter fuse. They would want real money though.

Lee

Lee
[email protected]
www.velocitysportswear.com

[Rstanley0312 0]

yoink

I've worked in software development and you're a far better engineer than I am, so you'll know where I'm coming from when I say the more functions you add to something, the more potential for unforeseen interactions there are...no matter how much testing you do.

GPS? MMS messaging?... really? THAT'S what we want from an AAD?


Please - at least make a model that just does what it's supposed to do (cut the reserve loop) with 99.999% reliability with a decent battery life and I'll buy it.
It's like me not buying a phone which has automatic sync to facebook and email. I just want to make phone calls and charge the thing as infrequently as possible. Everything else detracts from the main purpose...

Done. It's called a CYPRES

Life is all about ass....either you're kicking it, kissing it, working it off, or trying to get a piece of it.
Muff Brother #4382 Dudeist Skydiver #000
www.fundraiseadventure.com

[df8m1 19]

yoink

I've worked in software development and you're a far better engineer than I am, so you'll know where I'm coming from when I say the more functions you add to something, the more potential for unforeseen interactions there are...no matter how much testing you do.

GPS? MMS messaging?... really? THAT'S what we want from an AAD?


Please - at least make a model that just does what it's supposed to do (cut the reserve loop) with 99.999% reliability with a decent battery life and I'll buy it.
It's like me not buying a phone which has automatic sync to facebook and email. I just want to make phone calls and charge the thing as infrequently as possible. Everything else detracts from the main purpose...

LOL... You did not really think that idea was about building it into the AAD did you? That is funny! This topic will get stale real fast if all we talk about is what it will do lol..

If have found that indulging in tangents of thought that are ludicrous to the main topic at hand sometimes result in thinking of something beneficial (totally by accident) that other wise would not have been thought of..

Here is a hint, if it sounds absurd, then it probably is lol…

And as a previous poster pointed out (obviously a pro Cypress guy ) , everyone will have an alternative AAD to choose from.

[df8m1 19]

I would only rig up our drop test dummy with the GPS or Radar or what have you, but that is really thinking in a complicated sense.

There is actually a way to determine the error of the altimeter in different orientations or as you change orientations, but how we will do that is classified.

Rest assured everyone… This AAD will do nothing more than cut a loop, what happens after that is beyond my influence. There will not be any GPS, no Cellular, no Facebook, no Twitter, no ordering pizza, no reminders to pick up the dry cleaning on the way home, no log book, no coleslaw either.. Not even a data collector that jumpers can down load, that data is stored in a Micro-SD card inside the box, inside the container. Post incident, that card will be accessible by opening up the box, and the data can be sent to us for analysis, or they can send the hole AAD.

What it will do is wait until you are out of the plane before it will fire, it will have a tighter orientation altitude deviation, it will hold off from firing if it sees a main deployment just before it reaches the altitude that the jumper selected, it will determine that a Wingsuter has not deployed after they have exited the plane, and fire to get a canopy over their head at the altitude they have selected if they have not done so them selves.


I truly do not want anyone to misunderstand exactly what this AAD will do and not do. This is an AAD, with one task alone end of story. If there is any confusion as to how this AAD will differ from the previously mentioned Cypres, please post your question and I will do my best to clear it up.

[df8m1 19]

I was rushed for time on the last post so I forgot a couple of things I wanted to mention.

This AAD will operate on a "canopy over head" altitude that translates into a firing altitude. I think if you were to ask the majority of AAD users what altitude their reserve should be over their head given a firing altitude of 750 or even 1000ft and I bet most will not know. They will guess based on where they would like it to be, but they will have no idea how long it takes their reserve to open on average. (which does vary depending on the reserve and method of deployment).

This AAD will compensate the firing altitude for increased speeds in an effort to consistently achieve a canopy over head at the desired altitude, regardless on the descent rate of the jumper. I recall a post saying that different reserves take different times to open as a challenge to this concept. My answer is, and correct me if I am wrong, but the TSO limit in regards to time is 3 sec, and that is the longest that a reserve is allowed to take to open.

It would be fun discussing how we are going to do all of this, but I can’t, that is magic or the secret recipe if you will. It will be interesting to see if Airtec or AAD make any changes to their designs to incorporate any of the operational characteristics I have mentioned, of if they dismiss them and trudge forward.

Lee mentioned that the container manufacturers should be interested in supporting the development of this AAD as it would help reduce their exposure. That would be nice but I do not see that happening lol..

Interesting perspective on the ability for a rigger to pack a prototype up in a reserve. Of coarse the AAD will be passive initially, I will have the cutter plugged in, but visible outside the container. It is important to have the actual cutter in the mix as I want to test it in its proper configuration electrically speaking, so it is exposed to static as it would be in real life. I will be able to see if the cutter fires, and tell if the controller commanded it or if it was “unintended”.

I am not a rigger and I want to keep everything above board. AADs are beta tested all the time, so there has to be some way to do it legally. I agree there is no way a container manufacturer will sign off on an AAD let alone a prototype, but then again, from what I understand, a rigger can not install an AAD in a container that is not listed by the container manufacturer as being approved.. Is that not why people are so interested in which manufacturers approved the Mars for use in their containers?

[RiggerLee 61]

Is there a tunnel near you? It just occurred to me that the vast majority of your burble testing could be done in a tunnel.

Lee

Lee
[email protected]
www.velocitysportswear.com

[mcordell 2]

df8m1

from what I understand, a rigger can not install an AAD in a container that is not listed by the container manufacturer as being approved.. Is that not why people are so interested in which manufacturers approved the Mars for use in their containers?

Container manufacturers may say a particular AAD cannot be used in their rig. There is no requirement for them to authorize it. They are not TSO'd components. The authority for a manufacturer to ban a particular AAD if they deem it unsafe is that the reserve must be packed according to manufacturer instructions so if there is a specific instruction telling you not to install a particular AAD then you can't.

Looking through the wings owners manual there is a brief section on how to install a Cypres but no reference to any other AAD although you can install other computer based AADs.

www.facebook.com/FlintHillsRigging

[mark 102]

df8m1

I recall a post saying that different reserves take different times to open as a challenge to this concept. My answer is, and correct me if I am wrong, but the TSO limit in regards to time is 3 sec, and that is the longest that a reserve is allowed to take to open.

Reserves bigger than 250 ft^2 and certified after 1994, that is, certified under TSO-C23d or C23f, are allowed to open slower. Some examples are the PD-281, OP-253, and the TR-425 I recently packed in a big-boy rig.

How much slower? The short version is 0.01 seconds for every additional square foot over 250, or 1 foot of altitude loss for every square foot over 250.

The TR-425 could open in
3 seconds + ((425-250) * 0.01)
= 3 seconds + (175 * 0.01) seconds
= 3 + 1.75 seconds
= 4.75 seconds

The owner of the rig was comfortable at belly-fly speed of 160mph. The additional 1.75 seconds means he would need an additional 400 feet or so of altitude in case of an AAD fire.

Mark

[mark 102]

df8m1

Interesting perspective on the ability for a rigger to pack a prototype up in a reserve. Of coarse the AAD will be passive initially, I will have the cutter plugged in, but visible outside the container. It is important to have the actual cutter in the mix as I want to test it in its proper configuration electrically speaking, so it is exposed to static as it would be in real life. I will be able to see if the cutter fires, and tell if the controller commanded it or if it was “unintended”.

I am not a rigger and I want to keep everything above board. AADs are beta tested all the time, so there has to be some way to do it legally. I agree there is no way a container manufacturer will sign off on an AAD let alone a prototype, but then again, from what I understand, a rigger can not install an AAD in a container that is not listed by the container manufacturer as being approved.. Is that not why people are so interested in which manufacturers approved the Mars for use in their containers?

A master rigger would not need approval to install the unit in the main container, say, on the wall between reserve and main. Would that be close enough for testing?

Mark

[Nigel 0]

Why? - does 'New AAD made in USA...' mean better than 'Old AAD made in Germany (or Holland or Belgium or wherever)'? If that's the sales pitch, it will be an uphill battle outside the US.

More seriously...

Any AAD algorithm is a delicate balance of 1) getting the thing to fire when it should vs 2) not letting it fire when it shouldn't.

Getting 1) right is mostly more important than 2): an AAD going off in the plane can be dangerous, but is mostly nuisance. An AAD not going off when it's needed is mostly fatal. The fast-swooper firing problem has largely been solved by application-specific algorithm improvements.

But getting that algorithm right is difficult - especially when the failure conditions are rare, which means difficult to replicate and therefore predict.

So having had a device on the market for a long time is advantageous - those rare failures can be analyzed, and maybe even trends spotted. Which leads to improvements such as the 'Expert' Cypres version.

But it also makes it difficult for newcomers - they won't have the hard-won experience and wisdom the incumbents have.

And translating a military/professional product to civilian/amateur users isn't simple: the risk:cost equation will be different for military vs civilian applications.

Generalizing: professional/military users are younger, fitter, better trained, more current and ultimately expendable, whilst civilians are older, slower, less current and not expendable.

The cost of ownership and inconvenience of serviceability issues clearly aren't decisive for most jumpers.

Challenging the status quo is always good. Improving upon it is another matter...

Good luck!

[mxk 1]

mark

***I recall a post saying that different reserves take different times to open as a challenge to this concept. My answer is, and correct me if I am wrong, but the TSO limit in regards to time is 3 sec, and that is the longest that a reserve is allowed to take to open.

Reserves bigger than 250 ft^2 and certified after 1994, that is, certified under TSO-C23d or C23f, are allowed to open slower. Some examples are the PD-281, OP-253, and the TR-425 I recently packed in a big-boy rig.

How much slower? The short version is 0.01 seconds for every additional square foot over 250, or 1 foot of altitude loss for every square foot over 250.

The TR-425 could open in
3 seconds + ((425-250) * 0.01)
= 3 seconds + (175 * 0.01) seconds
= 3 + 1.75 seconds
= 4.75 seconds

The owner of the rig was comfortable at belly-fly speed of 160mph. The additional 1.75 seconds means he would need an additional 400 feet or so of altitude in case of an AAD fire.

Mark

This is why I mentioned that usable flight time after opening is the ideal objective for determining when to fire, but then the AAD needs to know what reserve it is deploying. It will have to contain a database of known reserves and probably an option to manually specify the maximum deployment time and distance.

Just to add a correction, the increase in time or distance is according to the maximum operating weight (MOW), not parachute size. TSO-C23f also factors in maximum pack opening speed (MPOS):

TSO-C23d

For parachutes with a maximum operating weight of greater than 250 lb (113.4 kg) the maximum allowable opening time shall be increased by 0.01 s for every pound of maximum operating weight in excess of 250 lb (113.4 kg).

-OR-

For parachutes with a maximum operating weight of greater than 250 lb (113.4 kg) the maximum allowable altitude loss shall be increased by 1 ft for every pound of maximum operating weight in excess of 250 lb (113.4 kg).

TSO-C23f

(a) The greater of 3.00 seconds or the value determined as follows:
Opening Time Allowed (sec.) = (MOW – 250) * 0.01 + (MPOS/150 * 3.0)

-OR-

(b) The greater of 300 feet or the value determined as follows:
Altitude Loss Allowed (ft) = (MOW - 250) + (MPOS/150 * 300)

[RiggerLee 61]

Actually I would say that historically 2) has been more of a problem then 1). And I think the existing flaws of the current designs are larger then you seem to think. There is a tendency to look at these devices through rose colored glasses. It makes us feel warm and fuzzy and safe. When the truth is that there are major flaws that can kill you or fail to save you. I say flaws but that's not really the right word. There are not really flaws in the existing systems. The truth is that they are limited. They are hard up against a technological wall and I really don't think their designs can go any farther. And the solutions they are coming up with for some of these limitations cause problems in them selves.

You bring up the new swooping algorithms. That is a perfect example. If you are flying a fast canopy and are thinking about getting one of these swooping units you really, really need to take a hard look at what is going on there. You need to see the lecture, I wish some one had recorded it, on how the swooping vigil works. You need to understand what you are giving up when you put one of those things on your back. You talk like, oh that problem is solved. Before you say that you had better take a hard look at the solution. Don't get me wrong, it's the best solution that can be applied to that unit but it's at a high cost.

People are hitting the ground following AAD fires. I don't want to get into debates on where the real problem is coming from. I don't think it's an AAD problem. But the AAD manufacturers are trying to fix it. But look at the fix. They are moving the altitudes up. That's the only solution available to them. But that moves the whole window up raising the danger of two outs. We're changing the BSR's to try to make room for it and reduce the danger or at least the liability of two outs. Pretty big trade off.

None of them really have a solution for a wing suiter. Or low cutaways. Or canopies that open slower at terminal. And it's not like they aren't trying. There just isn't a solution that exist in the current technology. What this guy is talking about in this NEW AAD is a whole nother ball park. He's breaking new ground. You can't even see the old ground from here. "Status Quo"? This isn't an improvement on the status quo. This is a fresh sheet of paper that leaves all the old rules behind. This isn't out side the box, he threw the box away in the trash. Box? What box? This is an opportunity for some thing new that can surpass the operating limitations of the old units. To do that we first have to be honest about the failing of the old unit. It's time to talk about the problems with them and to do that we have to get over the propaganda that every thing is fine and that the units are perfect and infallible. I'm not sure how much of that is created by the companies and how much we have created our selves. It's certainly easier not to think about these problem but progress is based solely on hard objective reality, not wishful thinking.

End of rant.

Lee

Lee
[email protected]
www.velocitysportswear.com

[df8m1 19]

mxk

This is why I mentioned that usable flight time after opening is the ideal objective for determining when to fire, but then the AAD needs to know what reserve it is deploying. It will have to contain a database of known reserves and probably an option to manually specify the maximum deployment time and distance.

Jumpers need to know how their gear performs, every piece of it. The larger canopies such as the example above are definitely outside the normal "solo" realm (IMOP) and are in the tandem crossover range. I certainly hope the jumper jumping the reserve mentioned has adjusted his AAD to compensate for the additional vertical distance his reserve needs to open!

There is a way to do it and keep it pretty straight forward. Can’t go into how, but don’t panic yet lol…

[RiggerLee 61]

As to approval of installation and whether the manufacturer of the container has to approve it in writing. I'm guessing you were not in the technical, or maybe it was the rigging, meeting of PIA before the symposium. Apparently there has been a question put forward by the FAA. I think it was, "How may a rigger know what AAD's are approved in what rigs?" So from what I gather, right now there seems to be no approval or approval process, but the FAA is thinking that maybe their should be? Get with Terry Urban or some of the guys active on the technical commity.

So right now I don't think you need an approval to put a inactive AAD in a rig. I think putting an active AAD in a rig will be mostly about the question, "can it interfere with the normal opening process of the rig?" The way they seem to have approached it up to now is to say that since it does not interfere with normal operation then it does not affect the airworthiness or TSO of the container.

This may now be in flux so get with the guys on the technical commity. Terry seems to be one of the most rational of them.

Lee

Lee
[email protected]
www.velocitysportswear.com

[df8m1 19]

That is very interesting... I will certainly take your advice. If the FAA is going to start to get involved with AADs, it would make sense, given where this one is in the process, to get inline with any FAA requirements or guidelines that may be in the works..

My only concern is in regards to the rigger who seals the reserve. I have to look out for him / her / them as eventually the validation will expand to several rigs with active units in them and I want the reserve seals to be legal.

From a container manufacturer’s perspective, plausible deniability would be my preferred defense lol...

I wonder what has spurred the FAA to start to question AADs. I posted some questions about a TSO like test standard for AADs in a thread some time ago and it was like I was playing dodge ball lol...

Very interesting in deed...

[df8m1 19]

RiggerLee

Is there a tunnel near you? It just occurred to me that the vast majority of your burble testing could be done in a tunnel.

Lee

I have thought of that and wonder if the negative pressure above the jumper would have some influence on the measured pressure at the boundary layer behind the jumper compared to free fall.

I plan on preforming test in both mediums and see how they compare. I have a laboratory wind tunnel that we use to calibrate the air speed sensor in the Flight Data Recorder, but is only has an 8" test section diameter

I bet the magnetic sensor will be useless in the tunnel, but we could still use the accelerometer to cross reference orientation to pressure.

[Nigel 0]

RiggerLee

Actually I would say that historically 2) has been more of a problem then 1). \

That is inevitable if the designers prioritize 1) over 2), which I hope they did.

But no same unit can get 1) and 2) right 100% of the time. If you want more of 1) you will have less of 2) and vice versa. It maybe as close as 99%/100% vs 100%/99% respectively, but it's never going to be 100%/100%.

It's similar to the sensitivity/specificity paradox for screening tests like mammography or PSA: there's a trade-off between false-negatives (unacceptable in a screen) vs false positives (undesirable, but manageable). So screening tests have very high sensitivity, but lower specificity. Which is why there are confirmatory tests.

But there's no time for the confirmatory test equivalent for AADs: they have to get it right the first time, not after the fact.

Sorry, but I'm just not a fan of the 'new sheet of paper' argument: I want some track-history, even if it's imperfect.

I've no idea who df8m1 is, but his opening pitch suggested being made in the good ol' US was an attribute worthy of consideration when buying an AAD. Sorry again, but that cuts no ice with me, which is why I drive a 911 and not a 'vette....we should probably take this outside!

[df8m1 19]

Nigel

[

Sorry, but I'm just not a fan of the 'new sheet of paper' argument: I want some track-history, even if it's imperfect.

I've no idea who df8m1 is, but his opening pitch suggested being made in the good ol' US was an attribute worthy of consideration when buying an AAD. Sorry again, but that cuts no ice with me, which is why I drive a 911 and not a 'vette....we should probably take this outside!

With any luck Airtec and AAD will keep making the same AAD as they have in the past so there will be a comfortable alternative to choose from lol..

I'm not a Vette guy either, never saw the apeal even after building a couple of them, I prefer the comfort and performance of my 84 diesel Benz lol

There will always be Cypres buyers, Vigil buyers, and maybe Mars buyers, that can not be swayed, no matter what, and I think that is a good thing... I mean how can something claim to be the best without something bellow it to refference to?