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skydiverek

Mirage MARD is out

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councilman24

Some show us a photo of the bridle after a 'trap', both low and high speed reserves. Debating on the fabric on fabric friction.


Also,
The Skyhook, Booster, RAX, and Air Anchor are all intended to disconnect if a horseshoed main is cut away, which allows the possibility of using the reserve pilot chute to deploy the reserve. It appears as though once the Trap is sprung, it does not release. If so, it would tow the reserve pilot chute in the cutaway horseshoed main scenario. Perhaps I am missing something; I hope I can be corrected.

I don't think there are enough data points for us to say which scenario is preferable: the MARD disconnecting when you want it connected (as with Skyhook, etc.), or staying connected when you want it disconnected (as may be the case with Trap).

Full disclosure: I have done some work on competing MARD prototypes.

Mark

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I like the old acronym KISS (Keep It Simple Stupid). Adding systems on top of systems that already have somewhat similar systems really provides more room for errors to occur. You've got one handle to cut away and one handle to deploy the reserve... and that is about the highest level of complexity I like to see on rigs. And all that other added complexity for roughly 1 sec of time... :P
Woot Woot!

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colossus

Kelly. Any thought to adding something like this to the Infinitys?



Kelly's RAX is still my favorite MARD by far, and I'm still surprised that he is not using it.

When I say "my favorite", you should read it as :" I don't really like MARD for sport rigs, but if I have to work with them, RAX is my favorite"
"My belief is that once the doctor whacks you on the butt, all guarantees are off" Jerry Baumchen

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It's a great concept. The piece they aren't showing is the lanyard that opens the reserve container. How does that fit into the mix?

My issue with it is that elastic loop that the bridle tucks under. I think it needs to be a pocket. Just speculating here-but if a lazy/inept rigger advances even an inch long bight through that loop and the "snare" collapses around it: you've got a main girth hitched to your reserve bridle and the jumper is totally screwed.

I am curious to see this thing. Might be alright, guess we'll see...
"Sometimes you eat the bar,
and well-sometimes the bar eats you..."

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I was wondering about the same scenario. Hadn't had time to think it through. It may be a cutaway horse shoe would extract the bridle from the trap. And still get nervous about fabric on fabric, especially at high speeds. That come from rock climbing/rope rescue training to never have moving fabric on fabric.

And like others I don't much like MARDS at all. Even after they reenforced the RAX after I started pulling the demo mock up apart.:P
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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Quote

Also,
The Skyhook, Booster, RAX, and Air Anchor are all intended to disconnect if a horseshoed main is cut away, which allows the possibility of using the reserve pilot chute to deploy the reserve. It appears as though once the Trap is sprung, it does not release. If so, it would tow the reserve pilot chute in the cutaway horseshoed main scenario. Perhaps I am missing something; I hope I can be corrected.



Mark, as I was I too worried about this. I own both a Vector with skyhook and a Mirage. I am a fan of the Mirage, so I want them to be successful.

My only Skyhook reserve ride - the skyhook prematurely released so it was a normal RSL deployment. So I am shooting 100% failure on that system:P, but it "failed safe".


The Skyhook is designed to release when the reserve PC is actually pulling instead of being taken for a ride by the main canopy... In a horseshoe or entanglement where the main cannot fully leave, the Skyhook should release, which is a very good thing... This Mirage MARD, if it does not release, could cause a PC in tow on the reserve (fatal).

In this system, I would really want to see what would happen if the PC started working again, would the bridle pop out, does it unload and release on its own?

I also agree that I would be concerned with fabric burns and loading... We were doing static line jumps off of the Bridge testing various systems, and sure enough, we discovered how easy it is to leave the PC and half the bridle on the bridge when break cord ended up being stronger than the bridle webbing due to fabric burns and knots being loaded and melting materials.

If the RSL cuts off the PC, well.... Game over. What testing was done in this regard?

And - in case people question how much force is on a RSL and why I am concerned -- my last cutaway my Mirage RSL lanyard hardware broke at the riser connection point. There was evidence that the RSL was loaded enough to kink the previously never used cutaway cable, thus it was loaded substantially before it broke... Unfortunately the RSL never was found, it came out of the rig, so the point of failure is unknown.

(Mirage sent me a nice email explaining it was my user error that the metal clasp must have been open... I disagreed because if that was the case the ripcord would not have been kinked, the RSL would have still been installed, and my A licence checkout student would have failed the gear check portion of his jump when he checked my gear in the plane and before we got on the plane).


All that being said, I love Mirage, and I love the fact they were confronted with a patented Skyhook, and a lawsuit by a fellow poster in this thread - and instead of giving up, invented something new! That is why ultimately I am a Mirage fan, even though I am highly critical here. I admire Bill Booth, he can come off cocky at times, but he freely talks about his test jumps and designs, I want to hear Mirage's testing.....

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Hi Terry,

Quote

Even after they reenforced the RAX after I started pulling the demo mock up apart.



Well, that 'they' would be me.

Now to be factual:

1. You applied a load in a manner that it would never see in service. I'm OK with that; things can be learned by doing things like this.

2. It did get me to change the design so you could not do this again. That is a good thing; so Thank You.

3. I did not 'reenforce' it, I changed the design.

And for those not too familiar with the RAX System vs other pin type systems; in a pilot chute first deployment the RAX does not pull any pin to release, it pulls away from the pin which remains stationary.

Jerry Baumchen

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tdog


If the RSL cuts off the PC, well.... Game over. What testing was done in this regard?.....



To my knowledge,no MARD was ever tested in a horseshoe situation.
"My belief is that once the doctor whacks you on the butt, all guarantees are off" Jerry Baumchen

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stayhigh

What happens if the rigger stuffs the reserve bridal in the elastic past the redline?



That's a pretty good question. I imagine it wouldn't be possible to wrap around the elastic, thanks to the net, but if the bridle extends too much after the red line the net might not be enough, and the loop will be trapped (pun intended) around the net, blocked by the bridle stiffener and fabric. If that happens the RPC might not be able to pull the free bag, since the bridle might be trapped, and the main might not leave. It would be some sort of tension knot between the MARD loop and the reserve bridle, with a little bit of horseshoe. Am I missanalyzing something? As somebody else suggested, why not using a pocket?

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Deyan

***
If the RSL cuts off the PC, well.... Game over. What testing was done in this regard?.....



To my knowledge,no MARD was ever tested in a horseshoe situation.

Maybe not a horseshoe.... But the skyhook design took into consideration that it should release when the reserve PC was loaded.... In May this year Bill posted to another thread how the skyhook releases....

Quote

You see, the MARD connection pulls on the reserve bridle near the midpoint, which means that it is pulling on both the bag and the pilot chute. If there is a lot of horizontal speed involved (spinning malfunction), then the pilot chute often generates enough force to prematurely release a simple pin/loop system, which will release as soon a the pilot chute loads at all. I needed to work out a system where it took a lot more force from the pilot chute to release the MARD connection in a partial malfunction than in a total malfunction. This is where the Skyhook lever/cam design came in. It is designed to require 5 times more force from the pilot chute than the weight of the packed freebag (25 - 60 lbs.) if you have a partial malfunction, yet release with a force of between 4 and 8 lbs. if you have a total malfunction.




Don't get me wrong, I like the mirage design, creative new way to solve a mard... Just debating if the system needs to be able to release post activation...

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I've heard and seen unspeakable shit happening during repack, like flip thru.

I feel like there will be some dumb ass rigger who will stuff the bridal way down past the redline. What's the downside of using a pocket?

I can kinda see if you stuff bridal way past the redline it might bunch up and lock itself in.

Normal RSL works fine. Don't know why there is such a trend of skyhook becoming a necessity. You sit a square one and newbies asks this question all the time. "Does it come with a Skyhook?"

If you chop above 1000ft I don't see any reason for Skyhook being a absolute necessity.

I've seen one dumbass who firmly believed in his Skyhook and he lowered his deck to a 1000 ft. I repeatedly told him that the Skyhook does not engage sometimes, but whatever not my problem.

Give me a normal RSL. So much simpler design. Proven over time. Some even thinks that normal RSL complicates the design.
Bernie Sanders for President 2016

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councilman24

I was wondering about the same scenario. Hadn't had time to think it through. It may be a cutaway horse shoe would extract the bridle from the trap. And still get nervous about fabric on fabric, especially at high speeds. That come from rock climbing/rope rescue training to never have moving fabric on fabric.

And like others I don't much like MARDS at all. Even after they reenforced the RAX after I started pulling the demo mock up apart.:P



Whether or not it releases from the trap seems to be dependent on the load being applied to the trap at the same time the load is applied to the PC. In theory, if a horseshoed main were to be cut away and the reserve pc inflates and pulls on the bridle at the point where the trap is wrapped around it, so long as there isn't significant tension on the trap, the bridle should have enough force to remove itself from the slip knot. If there is a lot of tension on that knot then I can see it holding in spite of the pull force of the PC. I'm having a hard time picturing it in my head to decide what the more likely scenario is but if the risers leave the shoulders and travel up with the knotted up bundle of crap it seems possible the tension would be released from the slipknot around the bridle.
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mcordell

. . .if the risers leave the shoulders and travel up with the knotted up bundle of crap it seems possible the tension would be released from the slipknot around the bridle.



The noose tightens around the bridle above the folded stiffened section created by the narrow-folding and sewing. You would have to do more than just release tension on the noose to release after that. You would need to apply enough force to loosen it: the reserve pilot chute pulling on the bridle would need to spread the folded portion enough to overcome friction and the noose-tightening force from main canopy drag. I'd be interested to find out if and how this scenario was tested.

As another poster has noted, this is not a TSO-required test scenario.

It's a trade-off. Faster deployment in most situations (whether you need it or not -- how about just not visiting the basement?) vs. complexity and some possible failure modes in rare situations.

Mark

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stayhigh

Give me a normal RSL. So much simpler design. Proven over time. Some even thinks that normal RSL complicates the design.



I think the Skyhook has been proven effective and safe overtime too. Just sayin.....

I know it has not been out as long as a standard RSL but it has been out for some time.
Life is all about ass....either you're kicking it, kissing it, working it off, or trying to get a piece of it.
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gowlerk

I like it. The need for hand tacking it means that someone will do it wrong before long. But it will not interfere with normal deployment. Unless someone tacks down the bridle itself. I'm not going to pretend that I'm even near smart enough to figure out if this can go wrong somehow, but I really like the concept. It seems to follow the idea of "first, do no harm" better than any other system.



The one rigging mistake I can think of, is: if instead of routing the bridle on top of it and from outside to outside again (the way the video shows), you route it either below and outside, or inside and then outside, then if you straight to reserve you have created a reserve container lock because the bridle will be clipped in the trap loop. I am not even sure this is possible or that this would happen, not to mention a very unlikely rigging mistake, I am not a rigger or that experienced for what's worth, but it's the first thing I thought when wondering "what could possibly go wrong".
The only other thing I thought is: no system to cutaway the opposite side riser? Or they simply didn't show it?
Also, they don't show if there is still a way to pop the reserve pin independently of the MARD working or not, like the skyhook which is in the worst case scenario, always at least an RSL.
So, I am very very very interested in this system and I really want to find out more! :)
I love the idea of no-interference and I was really happy to finally see a video that gave us an idea on how they did it!
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My body screams release me
My dreams they must be fed... You're in flight.

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Di0


The one rigging mistake I can think of, is: if instead of routing the bridle on top of it and from outside to outside again (the way the video shows), you route it either below and outside, or inside and then outside, then if you straight to reserve you have created a reserve container lock because the bridle will be clipped in the trap loop.


If I read that correctly, that would require you to intentionally run the freebag through the mard lanyard before packing the reserve into it which wouldn't happen unless you did it on purpose. You wouldn't have to worry about that.
Quote

The only other thing I thought is: no system to cutaway the opposite side riser? Or they simply didn't show it?


This is what people are referring to when they talk about a Collins lanyard. That is designed to release the opposing riser in a scenario where one riser releases. This system does not have it.
Quote

Also, they don't show if there is still a way to pop the reserve pin independently of the MARD working or not, like the skyhook which is in the worst case scenario, always at least an RSL.


The reserve operates as normal if the reserve handle is pulled since the trap operates only when the rsl is pulled under tension in a cutaway. Nothing would keep you from pulling the reserve manually.
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Rstanley0312



I think the Skyhook has been proven effective and safe overtime too. Just sayin.....



Safe possibly (I do not know of any incidents caused by Skyhook), but definitely not always effective.

There are many occurrences of Skyhook failing to beat the reserve pilot chute. In that case it is an expensive complication on the rig.

I am not convinced of the need to 'better' the standard RSL.

I'd be interested to hear from Kelly why Velocity have not pursued a MARD on the Infinity. That's a guy who does a lot of thinking about rig design and I'd value his input.
"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

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