RSL ground detachment (Re:skyhook).

[Freeflysmiley 2]

Just a thought I had the other night.

In the past there has been a widely put about myth that if you landed on a windy day in a dangerous place ( on a roof for example) and you had to cut your canopy away ( to avoid being dragged over the top for example) then you had to detach your RSL or your reserve would come out and put you back in the same situation.

This of course is bollocks, as only the reserve pilot chute would come out, which isn't going to drag the reserve out and put you in a fix.

HOWEVER, with the advent of the skyhook, which I have myself, unless I'm missing something it would do exactly that. The main could drag your entire reserve canopy out. Unlikely I know but possible with a departing main canopy and strong wind.

So just a thought, maybe us skyhook owners should make sure the RSL is detached prior to a ground cutaway ( although I hope we never find ourselves on a roof !)

P.S does anyone know if BB tested this scenario?

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Practise the 6 P's!
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[Davew 0]

I wondere if BB has thought of this scenario: You have a pilotchute hesitation or a momentary baglock. Just as you cutaway your main opens. With a skyhook you now have a canopy sized pilotchute and you are still at terminal. The result could be an opening hard enough to kill you or shread your reserve. The skyhook is great subterminal, just as a huge pilotchute is great for short BASE delays.

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[efex 0]

I dont understand what you mean. Since when does a terminal reserve opening kill you? If you didnt have a SkyHook you would be going just as fast when your reserved opened.

Warwick University Skydiving Club

[AggieDave 6]

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Just as you cutaway your main opens. With a skyhook you now have a canopy sized pilotchute and you are still at terminal. The result could be an opening hard enough to kill you or shread your reserve.

In that instance, as I understand it, wouldn't the reserve PC beat the canopy beginning to come out of the bag and thus open as a normal RSL deployed reserve? The only way I can see your scenerio working in the manner you described is to have a baglock that then opens with an "instant canopy" sub 100' snivel main opening the millisecond prior to you cutting away...just as you are pulling the cutaway handle to release the 3-rings.

Since if you had PC hesitation, the main would be in the bag still in the container, if you chopped it and pulled the reserve and just as you chopped it, the main lifted out of the container, the reserve would still deploy normally. Lets say that the main lifts out of the container and gets enough drag as the lines pull out of the stows to pull the risers out of the riser covers and the reserve is pulled by the RSL, the reserve PC would still fire out quicker and thus disengage the Skyhook (as it was designed to do).

Now, lets take the baglock scenerio and lets just say that the baglock has produced enough drag to stand you up some. Now you're already going faster then normal, lets just say 130 mph, since you're not in a neutral body position on your belly. You cutaway and just as you cutaway the main begins to come out of the d-bag. Is the fabric presented that much larger then a typical reserve PC? Slightly. Would the Skyhook disengage due to the reserve PC catching air faster and disengaging the hook? Maybe. Would either of those situations be bad? Well, to a point, since you're going slightly faster then normal. Would the Skyhook in those scenerios give you an instant reserve? Nope. Since if you had enough main canopy out to make the Skyhook work instead of having a typical RSL pulled reserve, then you would be going slower then terminal.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[sundevil777 102]

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You have a pilotchute hesitation or a momentary baglock. Just as you cutaway your main opens. With a skyhook you now have a canopy sized pilotchute and you are still at terminal. The result could be an opening hard enough to kill you or shread your reserve. The skyhook is great subterminal, just as a huge pilotchute is great for short BASE delays.

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It is still just a pilotchute, so you might have more snatch force than normal, but even that would be over very quickly since it can't provide any more force once the freebag has separated.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

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[ZigZagMarquis 9]

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The result could be an opening hard enough to kill you or shread your reserve. The skyhook is great subterminal, just as a huge pilotchute is great for short BASE delays.

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Ummm... not really. How is this much different then a terminal reserve ride? You don't think your reserve is going to blow-up if you have to use it terminal because of a hard-pull, total, etc., do you? Yes, the skyhook and main are going to drag your reserve out, by design, but remember... "free bag".

I would like to hear Bill's take on it, but IMHO, this isn't an issue.

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[980 0]

Your example is flawed too, since a reserve deploys from a freebag and a BASE canopy has the pilotchute connected directly to it via the bridle.

Therefore a reserve canopy can only be pulled to linestretch by as much force as the freebag locking stows allow, exert more pull on the freebag than that and you will strip it off the reserve before linestretch.

Exert enough force on the freebag and you can strip it off the reserve without removing the reserve from the container, as per this: bag strip

But that was accounted for in the skyhook design as discussed in the linked thread.

Think about it.

[leapdog 0]

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I wondere if BB has thought of this scenario: You have a pilotchute hesitation or a momentary baglock. Just as you cutaway your main opens. With a skyhook you now have a canopy sized pilotchute and you are still at terminal. The result could be an opening hard enough to kill you or shread your reserve. The skyhook is great subterminal, just as a huge pilotchute is great for short BASE delays.

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Are we assuming that the RSL is a primary means of reserve deployment and not your left hand?

In a bag lock or any other mal, you look right grap right, look left grab left, then pull right, pull left. The reserve pilot chute will deploy and the skyhook will slip off the lanayd and the main if it were to open will not help pull the reserve. I think it was also pointed out that at terminal a reserve deployment snatch force won't kill you.

I use a skyhook. As any experienced skydiver should know you have to mold your procedures according to the equipment you jump.

Gunnery Sergeant of Marines
"I would like it if I were challenged mentally at my job and not feel like I'm mentally challenged." - Co-worker

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[davelepka 4]

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The result could be an opening hard enough to kill you or shread your reserve.

If this happens it's your riggers fault, not the skyhook.

Once the reserve clears the freebag, the opening is all slider. If you hooked the Skyhook to your slider, you might have point. Otherwise, you've got your facts a little mixed up.

[pilotdave 0]

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In a bag lock or any other mal, you look right grap right, look left grab left, then pull right, pull left. The reserve pilot chute will deploy and the skyhook will slip off the lanayd and the main if it were to open will not help pull the reserve.

I think you'd have to pull left then pull right for that to work, or maybe pull them at the same time. You're not going to beat any RSL unless you pull out of order. The skyhook should work as designed if you pull right then pull left.

Dave

[leapdog 0]

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In a bag lock or any other mal, you look right grap right, look left grab left, then pull right, pull left. The reserve pilot chute will deploy and the skyhook will slip off the lanayd and the main if it were to open will not help pull the reserve.

I think you'd have to pull left then pull right for that to work, or maybe pull them at the same time. You're not going to beat any RSL unless you pull out of order. The skyhook should work as designed if you pull right then pull left.

Dave

Just as I have stated, pull right then pull left. You wouldn't beat the RSl, you wouldn't have to. It would function just as I described and designed. Bag lock remember? So the Main wouldn't be pulling anything to begin with. The hook would slip from the lanyard the reserve PC would deploy the reserve, the main would not be connected.

I have one and have used it.

Gunnery Sergeant of Marines
"I would like it if I were challenged mentally at my job and not feel like I'm mentally challenged." - Co-worker

[riggermick 7]

Bag lock remember? So the Main wouldn't be pulling anything to begin with. The hook would slip from the lanyard the reserve PC would deploy the reserve, the main would not be connected.

Bag locks will provide enough drag to pull you upright, seen a bunch of them, so the Sky Hook will work as intended using the drag created by the main pilot chute and lines of the canopy. There is well over 100 lbs pulling the risers at the time of release. So I think the point is kind of moot.

Mick.

[riggerrob 643]

Good logic.
It is doubly important to use the old procedure with new equipment.
When being dragged on the ground, it is doubly important to disconnect a Skyhook, because - if you don't - it will pull the reserve to line stretch and strip off the free-bag, vastly increasing the chances of the reserve inflating.
Mind you, when winds get up around 20 knots, I always disconnect my RSL at 1,100', just before I get busy in the landing pattern.

[riggerrob 643]

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I wonder if BB has thought of this scenario: You have a pilotchute hesitation or a momentary baglock. Just as you cutaway your main opens. With a skyhook you now have a canopy sized pilotchute and you are still at terminal. The result could be an opening hard enough to kill you or shread your reserve.

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Your logic is flawed.
Skyhook does nothing to the slider.
The slider will still slow your opening to a tolerable speed.

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[sundevil777 102]

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Bag lock remember? So the Main wouldn't be pulling anything to begin with. The hook would slip from the lanyard

Not true.

The main PC is still pulling in a bag lock scenario.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[pilotdave 0]

Check out the 2005 skyhook video on my site or RWS's. They demonstrate a baglock. Skyhook works as advertised.

Dave

[diablopilot 2]

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I wondere if BB has thought of this scenario: You have a pilotchute hesitation or a momentary baglock. Just as you cutaway your main opens. With a skyhook you now have a canopy sized pilotchute and you are still at terminal. The result could be an opening hard enough to kill you or shread your reserve. The skyhook is great subterminal, just as a huge pilotchute is great for short BASE delays.

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Wouldn't be any different than a terminal reserve opening by P/C.

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You're not as good as you think you are. Seriously.

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[mjosparky 4]

You do know that reserve canopies are tested to a speed of 180 KEAS, which is above normal terminal speed?

Sparky

My idea of a fair fight is clubbing baby seals

[ZigZagMarquis 9]

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You do know that reserve canopies are tested to a speed of 180 KEAS, which is above normal terminal speed?

Sparky

Unless you're really good at head-down...

[Davew 0]

Good to see lots of replies to this one but you've all missed the point. It is a relatively common event for a baglock or hesitation to open just on cutaway without slowing down the jumper. If this happens the skyhook will remain attached. This will rapidly decelerate the bag. This means you have a great difference in speed between the jumper and the reserve canopy just as it emerges from the freebag. This translates into a high load on the suspension lines and a hard opening. The idea that because you have a freebag rather than an attached pilotchute doesn't change this. Pilotchute sizes are carefully calcutated to lift off the bag at just the right speed to have an acceptable diffence in speed between the jumper and the freebag. Otherwise you could just put a 60 inch pilot chute on your reserve and forget all about the skyhook.

[tdog 0]

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....

HOWEVER, with the advent of the skyhook, which I have myself, unless I'm missing something it would do exactly that. The main could drag your entire reserve canopy out. Unlikely I know but possible with a departing main canopy and strong wind.

So just a thought, maybe us skyhook owners should make sure the RSL is detached prior to a ground cutaway ( although I hope we never find ourselves on a roof !)

P.S does anyone know if BB tested this scenario?

It seems that this thread was hijacked from topic.

I have a skyhook, and I have visualized what you said... Being in tow (drug on the ground/roof/etc) and cutting away my main, to find it pulling my reserve out...

Now, the slider will still be up, but it might inflate quickly... And I would have a reserve open without a single toggle in my hand to shut it down too....

The few times I landed where I have been worried about shutting down my canopy after landing - I have released the skyhook at about 300' just in case I needed to chop after landing.

It is kind of a catch-22... I really don't want to disconnect the skyhook until I am low enough that I know the skyhook will be useless... The skyhook technology shines in situations where extra quick reserve deployment is a good thing, like a collision where the main might be torn and useless. By then the only other options are deploy a reserve into the torn main, or hit really hard... And say I panic and chop a really screwed up canopy collision low, like people have in the past, the skyhook might be the difference between landing under a barely flying reserve and landing with nothing out... (yes, if I get this far, I already have screwed up a few times, but anyone can screw up, especially under abnormal conditions)

[ZigZagMarquis 9]

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Good to see lots of replies to this one but you've all missed the point. It is a relatively common event for a baglock or hesitation to open just on cutaway without slowing down the jumper. If this happens the skyhook will remain attached. This will rapidly decelerate the bag. This means you have a great difference in speed between the jumper and the reserve canopy just as it emerges from the freebag. This translates into a high load on the suspension lines and a hard opening. The idea that because you have a freebag rather than an attached pilotchute doesn't change this. Pilotchute sizes are carefully calcutated to lift off the bag at just the right speed to have an acceptable diffence in speed between the jumper and the freebag. Otherwise you could just put a 60 inch pilot chute on your reserve and forget all about the skyhook.

Show me the Math... or are you just speculating wildly?


I don't believe you that this would be any worse then a terminal reserve hit.

[mjosparky 4]

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Pilotchute sizes are carefully calcutated to lift off the bag at just the right speed to have an acceptable diffence in speed between the jumper and the freebag.

Then why do most manufactures use the same pilot chute on every size rig they make? With some canopies the weight difference between large and small can be almost 50%. Freefall speeds can vary from just above 100 mph to around 180. How are they going to "carefully calculate" just the right speed.

Now I agree that the faster the deployment speed and the heavier the load the quicker the opening. But the reserve is test to a speed of 180 KEAS minimum, that’s 207 mph, with a minimum weight of 264. (TSO-C23d) And that is done 3 times on the same equipment. It is pretty hard to blow up the canopy if you stay within those parameters.

Now if surviving an opening at speeds above 200 mph is another question.

Sparky

My idea of a fair fight is clubbing baby seals

[Freeflysmiley 2]

Hi, Yeah I wasn't suggesting disconnecting routinely at low level. After all the scenario is pretty unlikely. Just something for us skyhook owners to take into consideration.

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Practise the 6 P's!
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[riggerrob 643]

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Pilotchute sizes are carefully calculated to lift off the bag at just the right speed to have an acceptable difference in speed between the jumper and the freebag.

Then why do most manufactures use the same pilot chute on every size rig they make? With some canopies the weight difference between large and small can be almost 50%.

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Hah!
Last time I checked, Relative Workshop used the same pilot chute to lift 500 square foot military reserves and 97 square foot sport reserves.
One advantage of a free bag is that you only have to stock one size of pilot chute for all sizes of container. If the pilot chute is too strong for a 97 square foot reserve, so what? You don't feel any difference at line stretch, because the pilot chute disconnects a hundredth of a second later.

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