Airlocks

[SkySlut 0]

I am wondering what people think about airlocks. Could you please give me some feedback as to the pros & cons of having airlocks may be?
Thanks,
Slut

[numskull99 0]

Well the Pro's are it is much more stable of a air foil.
It will go through turbulance and things of that sort better. Because it won't collapse like normal ram air's.
Con's are Packing sux, trying to get the air out is not fun.
And also trying to get it to collapse in high winds isn't fun either.

[Geoff 0]

I have heard that after a cutaway, an airlocked canopy can stay inflated and continue to fly, potentially ending up miles away.
Does anyone know if there's any truth in this?
Geoff

[grasshopper 0]

I heard that story too about the cutaway flying away. But I also heard that guy bought another airlocked canopy to replace the lost one. And I saw that happen on a tri-cell a few weeks back (the cutaway flying away that is)

[ramon 0]

My friend Tommy gut away his jedei and he found it about two miles from the DZ.
Lucky ha ha.
I imagine a spinning malfunction where the canopy is mostly inflated would be the worst scenario for it flying to Timbuktu, so keep your lines even, get good tight stows with 3" bites, leave a good 18" of line left over, and make sure you have good body position when you dump.
bloo skies
ramon

[SkySlut 0]

Good info so far. Does anyone have any evidence on the performance of an airlocked canopy??? How does it handle & perform in high speed turns, swooping & flaring. Is there a noticeable difference??? I am demo-ing before I am purchasing. My underlying question is: Other than stability, which is worth the extra money right there, what else am I going to get for my money by buying airlocks???
Thanks,
Slut

[numskull99 0]

Another cool thing about air locks it they stay inflated until after the surf is over. There for making longer surfs.
With normal Ram Air canopies like Stiletto, when you flare it kills some of the compression in the canopie. What it does is pushes some of the air in the canopie out the nose while your flaring. Where as airlocks help prevent that. I would think that the hook turns and things like that would be the same. As long as your loading it the same.

[SkySlut 0]

Thats cool...from what I hear, I am going to love one of these canopies.

[miked10270 0]

Hi there,
Airlocks:
The pros; More rigid & consistent airfoil so less compromise on shape. Unlikely to collapse. Can't wrap in collision (bounces off). Tolerates higher wing loading. Longer surfs.
The cons; Bigger pack volume. More expensive. Doesn't collapse after landing. UTTER SHIT TO PACK!!
Mike D10270 (who still wants one!).

[dsiegel 0]

They're not that hard to pack. I have over 50 jumps on the things and a brand new Lotus and it's the same as packing a Sabre II. There's no noticeable incerase in pack volume. There's a BIG increase in lift on landing, and that's what it's all about. I'm sold on airlocks and won't go back. I have TWO lotuses and love them!

[cobaltdan 0]

hi mike,

not trying to nit pick:

-airlocks do not improve your airfoil shape, if you look at an airlocked canopy you will see that it exhibits the same spanwise distortion as an equivalent design standard canopy. i.e. samuri vs stilletto. simply look at advertisement pictures of both canopies, you will notice that the airlocked canopy has non loaded ribs that float up higher than the loaded ribs forming a zig zag leading edge tape, just as bad as the stilletto. additionally airlock canopies exhibit an increased spanwise distortion when in brakes. (note as an airlock is a piece of fabric attached to the nose it could be designed to provide additional support to add rigidity and decrease distortion, but no airlock designs to date do so)

-unlikely to collapse. not true. locking air in your canopy will not stop a canopy from collapsing in turbulence. airlocked canopies can and do collapse. fly one because you like its flight capabilities, do not fly one because you have a false sense of security that it will save your butt in conditions that another canopy wouldn't.

-cant wrap: airlocked canopies in a hard bump will fold between the b-c lines initiating an unrecoverable spin.

-tollerates higher wing loadings: not true, atair 9 cell canopies followed by icarus tricell canopies have demonstrated the highest wingloading capabilities. current marketed airlock designs are rated for much lower wing loadings and as such not offered in very small sizes.

-longer surfs: not true. current stats from a year of competition puts the velocity at #1, competition cobalt #2, with icarus and precision tricells following. no airlocks i believe even placed in a full year of the para performance games.

-bigger pack volume: a bit, not enough to put you up a size.

-more expensive: a bit, in line with other high performance 9 cells.

-pain to collapse on landing agree with you there.

sincerely,

dan
atair

Daniel Preston <><>
atairaerodynamics.com (sport)
atairaerospace.com (military)

[Kirils 1]

"it is much more stable of a air foil" Interesting, but I'm sure I have read there is no imperical data to support this. On what do you base your claim?

"Slow down! You are too young
to be moving that fast!"

Old Man Crawfish

[Samurai136 0]

I jump a 136 Samurai Loaded at 1.3 to 1.4 range. On no wind days I can get 30 yards of swoop out of a 90 degree front riser turn. I could get more but I'm still developing my piloting skills.

Riser pressure is easy and I can drop about 500' to 600' of altitude on a single front riser revolution. The Samurai is more ground hungry than a vengeance or stilletto in full flight. On the other hand, w/ a bit of rear riser I've floated in from 2500'agl 4 miles out.

This weekend one of my friends was knocking airlocks and I asked her what she expected her canopy to do if she griped her rear risers at the top and pulled them down to her shoulders and held them there. A non-airlocked canopy will depressurize and go back to a snivel. I can hold my risers down as long as I want and the canopy will not return to a snivel. The canopy just loses forward drive and sinks.

Turbulence is tricky. My home DZ is gets rotors off a tree line to the south of the landing area. Sometimes I'll get a surge of drive about 20' off the ground just below the tree line. This weekend, first time, the surge hit right as I was flaring and dropped me 4'. I ended up skuffing the left knee of my jump suit and a few small raspberry bruises. Turbulence is always dangerous.

If you are a buying a canopy to qualify/ compete in swoop competitions, buy a cross-braced canopy. Otherwise, I recomend airlocks.

"Buttons aren't toys." - Trillian
Ken

[faulknerwn 36]

Quote

This weekend one of my friends was knocking airlocks and I asked her what she expected her canopy to do if she griped her rear risers at the top and pulled them down to her shoulders and held them there. A non-airlocked canopy will depressurize and go back to a snivel. I can hold my risers down as long as I want and the canopy will not return to a snivel. The canopy just loses forward drive and sinks.

I've owned canopies with airlocks in the past and they seem to help a little, but not as much as many people think. I put about 500 jumps on a Jedei 92, now own a Cobalt 75, and jumped numerous canopies in between.

The Jedei did seem more stable in turbulence. It also was very stable in slow flight modes (stacked on slower canopies.) It felt llike a rigid airfoil. I could very easily collapse mine by pulling down the rear risers however.I also could stall it with the toggles as well. Its an airfoil - you can do that on any canopy. I did manage on occasion to stall it on landing - purely pilot error but the airlocks won't save you from that.

The Jedei's and Samurai's are trimmed very nose down. This is good for a lot of things, but I can go a lot farther on a long spot on my Cobalt 75 than I could on my Jedei 92 - even at the heavier wing-loading.

While I thoroughly enjoyed my Jedei, I don't think the airlocks were a big deal. I would consider buying one again in a small size, but one of the big reasons I didn't even consider them for my last canopy was the cost was WAY higher than a Cobalt. I really enjoy how the Cobalt flies so I went with it.

[Zennie 0]

Quote

fly one because you like its flight capabilities

Exactly. I've flown a Jedei & a Vengeance. The vengeance is becoming my favorite main yet.

The thing dives like a mofo but I always feel like I'm in complete control of it. Plus it doesn't seem to have the rear riser oversteer that the Jedei had.

Some people have commented that the Vengeance is a Stiletto with airlocks. I've flown both a Stiletto 120 & a Vengeance 120 and they are two totally different animals in terms of flight characteristics. The Stiletto has way higher front riser pressure, and the flare is more difficult to get a good surf out of (IMHO).

What's interesting is that everyone says the Stiletto is "twitchy", but it was a heckuva lot more docile with the toggle inputs than my Vengeance.

Just my $0.02.

- Z
"Always be yourself... unless you suck." - Joss Whedon

[jerm 0]

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-unlikely to collapse. not true. locking air in your canopy will not stop a canopy from collapsing in turbulence.

no, but it'll certainly resist against it better than a non-airlocked canopy.

and you backed that up with

Quote

-pain to collapse on landing agree with you there.

so, which is it? will airlocks help prevent collapsing or not?

I know that they can not keep a canopy from ever collapsing, but they can make it harder, and that sounds like a good thing to me.

Landing without injury is not necessarily evidence that you didn't fuck up... it just means you got away with it this time

[ernokaikkonen 0]

>and you backed that up with
>
>
>

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-pain to collapse on landing agree with you there.
>

>so, which is it? will airlocks help prevent collapsing or not?

I think Dan meant that it's difficult to get the air out of the canopy _after_ landing. Carrying a king-size balloon back from the landing area on a windy day isn't my idea of a good time...
Erno

[flyhi 24]

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Carrying a king-size balloon back from the landing area on a windy day isn't my idea of a good time...

Agree. I saw an article by Brian somewhere on line, that gave steps for collapsing an airlocked canopy. It included:

1) Pull one toggle until the canopy does a 180 degree turn and dives nose first into the ground.
2) Back up toward the canopy and allow the canopy to collapse so that the nose is toward you and the top is on the ground.
3) Collect the lines as you move toward the canopy.
4) When you reach the canopy, grab the tail, snap it, and the air will come out.
5) Carry the now collapsed canopy to packing, not allowing the nose to see the wind.

It has worked pretty well for me, and you don't feel like someone in the Macy's parade.

Shit happens. And it usually happens because of physics.

[jerm 0]

Quote

I think Dan meant that it's difficult to get the air out of the canopy _after_ landing. Carrying a king-size balloon back from the landing area on a windy day isn't my idea of a good time...Smile

i know that's what he meant, but why would it be so hard to deflate on the ground, yet still be just as prone to collapse in the air as non-airlocked canopies?

last summer i watched half of someone's canopy disappear at 80'.... half the wing just deflated and collapsed.... sure, an airlocked canopy would have been affected by the turbulence, but i highly doubt (given even dan's admission of how hard it can be to get the air out of one), that half the air could have been evacuated form the wing in an instant.

THAT(unless i'm misunderstanding brian), catastrophic collapse, is the kind of thing airlocks are primarily designed to try to prevent.... sure enough turbulence will get the better of any canopy, but airlock are MORE likely to stay inflated and keep a wing above your head.

YMMV.. BSBD

-jerm

Landing without injury is not necessarily evidence that you didn't fuck up... it just means you got away with it this time

[flipper 0]

Hi
Heres my exp. of airlocked chutes (not much)..about 30 jumps on a veng.107...my normal chute is a stiletto 120 (900 jumps)

packing...not really a hassle little bit more material to get in the bag ...but no real drama
openings...much the same as a stiletto...but more chance of it diving off to the side or at the ground...i found that getting on the rear risers quickly does the trick
flying...i found that this is the chute for me...perfect...real easy to pull front riser ...very responsive to toggle inputs...all in im sold and have one on order
landings...more lift...more control..real easy to change your line during the surf if required...and yes they can be a bitch to control after you have landed if its windy...but the hassle is a small price to pay..

now the turbulence thing....my own personnel thoughts on this are that the veng maybe does cut through the bumpy stuff a liitle better than my stiletto but i wouldnt count on it and certainly wouldnt jump on bumpy days just because im on a veng/airlocked chute...if theres enough turbulence to collapse a stiletto itll fold an airlocked chute...been there and had my chute dissapear while still at 30 feet....i was lucky and just bent my ankle...wont ever put my self there again..if i can help it...

flipper

[polarbear 1]

I currently jump a Samurai 150; I have about 80 jumps on it now. I have also put about 30 jumps on a Vengeance 170.

I like both canopies alot. A large portion of the canopy, however, is the design parameters other than the airlocks...in other words, I don't think it is the airlocks that make them nice to fly.

I do feel both canopies are a little more solid in turbulence. However, this just means they are SLIGHTLY more resistant to turbulence. They can still stop flying and drop, even if they remain inflated. Remember that stability on a ram-air canopy comes from inflation AND proper line tension. If you hit turbulence with airlocks, you may remain inflated, but you can lose line tension and your wing may still distort. Even if your wing doesn't distort, it still needs smooth air to fly, and turbulence will disrupt that.

I do get bumped around in turbulence; I just notice that my wing is not doing an accordian-type movement like on non-airlocked canopies. I think it is good policy to not rely on airlocks to save you from turbulence.

I also notice that the stall is different on my Samurai, both on rear risers and on toggles. On open-cell canopies, the wing will eventually bowtie if I apply enough toggle/rear riser. On my Samurai, it basically stays inflated and just starts dropping. It seems to recover from a stall less violently, perhaps bacause the wing doesn't experience as dramatic shape changes (?)

As far as packing goes, I don't notice any added difficulty.
The canopy does stay somewhat inflated when you land; I don't have a big problem with this. If you had to walk a long way with it on a windy day it might get old fast.

As I mentioned earlier, I like both canopies a lot and have no regrets flying either.

"Holy s*** that was f***in' cold!"

[Zennie 0]

Quote

If you hit turbulence with airlocks, you may remain inflated, but you can lose line tension and your wing may still distort. Even if your wing doesn't distort, it still needs smooth air to fly, and turbulence will disrupt that.

I had a big scare last weekend that sort of underscores this.
It was semi-windy. I had been doing 180 front riser dives all day. The first mistake I made was committing to a 180 when I was feeling turbulence. I should have said "no" and cross/downwinded it.
But I didn't. I cranked the front riser and mid-dive I felt the canopy drop way more than normal. Almost like it went into freefall. I knew I had just hit a rotor and so I let up on the risers & started the flare. I was reacting to the drop I had just felt, so I flared too high and wound up in a stall about 20' off the ground. I held the flare where it was and then hit the last bit of flare I had left right before I hit the ground. I wound up PLF-ing and just getting a little dirt on my pants, but it scared the bejesus out of me.
So airlocks don't make you immune to turbulence. My canopy didn't collapse, but it still dropped when it hit turbulence.

- Z
"Always be yourself... unless you suck." - Joss Whedon

[Hooknswoop 19]

I recently had the chance to demo a Samari 95. Nice, on heading opening. It seemed to fly similar to a Stiletto. I played in deep brakes and I could see the difference the airlocks made, holding in the pressure, helping to keep the canopies shape and resist the stall. I didn't have the oppurtunity to fly it in turbulence, but I can see where airlocks would make a difference. I did a carving 180 front riser turn for landing. Front riser pressure wasn't too high, nice recovery arc, short flare stroke (PD type flare), nice swoop.

As a side note,

Brian Germain, un-selfishly, spent considerable time (at the Lost Prarie Boogie) teaching canopy control, basic techniques through advanced, w/ anyone that stopped by his tent. He is a tremendous resource for canopy pilots. He is very good at explaining complicated concepts in an easy to understand way. If you can't learn something from Brian, you just aren't trying.

Hook

[Yoshi 0]

I only have a few jumps on airlocked canopies, but I did hear that one of the reasons for the steep glide is because the airlocks not only hold air in, but also out...so to build more pressure in the cells the seeper glide attributes to higher pressure on the nose...not completely sure about this,but I thought it made sense. ???
yoshi

WEEEEEEEEEEEEEEEEEEEEEEEE!!!!

_________________________________________
this space for rent.

[billvon 2,396]

>but I did hear that one of the reasons for the steep glide is
>because the airlocks not only hold air in, but also out...

Where'd you hear that? Airlocks are specifically _not_ supposed to do this. They allow air in for pressurization of the canopy during opening and during changes in canopy volume and air pressure. They are supposed to keep air from exiting, but they are not perfect seals in that direction.