Chute Release close call - airholes?

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billdz

Got my new Chute Release yesterday, it's available for $130 with free shipping on Amazon. Tried it at today's launch on my Estes Vagabond. Set it to deploy at 300'. Did not deploy at 300' and it looked like a crash landing was imminent. However, the chute deployed at the last possible moment, with the rocket only about 60' off the ground, and all was well, a perfect landing. We were trying to figure out why it deployed so late. One guy said it was because we were on a small hill and the device was fooled about the distance. Another said it was because I did not punch an airhole into the rocket. I recall reading that altimeters require airholes, but there's nothing in the Chute Release instructions about a need for airholes. Any thoughts on what might have happened? Nytrunner Pop lugs, not drugs TRF Supporter Chute release shouldn't need a vent hole. The "landed on a hill" theory may have some merit. The chute release will base it's Ground Level datum on where you launch from. May have something to do with how/where it was tethered or how the chute was packed. Where did you get her the CAR? ksaves2 Lifetime Supporter TRF Lifetime Supporter Got my new Chute Release yesterday, it's available for$130 with free shipping on Amazon.

Tried it at today's launch on my Estes Vagabond. Set it to deploy at 300'. Did not deploy at 300' and it looked like a crash landing was imminent. However, the chute deployed at the last possible moment, with the rocket only about 60' off the ground, and all was well, a perfect landing.

We were trying to figure out why it deployed so late. One guy said it was because we were on a small hill and the device was fooled about the distance. Another said it was because I did not punch an airhole into the rocket. I recall reading that altimeters require airholes, but there's nothing in the Chute Release instructions about a need for airholes.

Any thoughts on what might have happened?
Unless you could see the descending rocket closely enough the behavior of the parachute in the slipstream can vary. If the chute has been packed tightly, it can develop a lot of creases and quite frankly that sometimes delays the filling. The harness can tangle and foul the chute release. Always put the chute release on the parachute and follow Mr. Beans technique for packing on his website. Do not put the chute release around the chute protector. Attach the chute protector securely to the harness so the chute pack and JLCR are pulled free right when they are blown out at apogee. Have the chute protector far enough away from the chute pack so it can't foul the chute opening once the CR releases it. One doesn't need the chute protector anymore after it has been blown out of the rocket. Get it out of the way. Set the chute release to deploy at a higher altitude. If you are at a large enough venue to allow this, do it. It gives more time for the vagaries of canopy filling to work themselves out and allow the chute to fill. If you're stuck doing a very low deployment, try to do it with fiberglass rockets that can better handle tumble recovery otherwise there is increased risk of failure.

I had a plastic chute display a "pulled taut" configuration in a MPR flight. It was shirtsleeve weather and rocket was not quite out of sight. Chute came out at apogee and the rocket was coming down fast enough for those to ask, "Is it dual deploy?" It wasn't, but as it got lower in a worrisome fashion, it was seen the chute was out, is wasn't broken or streamering
and it was above the rocket with the rocket dangling below in a good position. It appeared the chute was being "held" in a "pulled tight" condition! As it got lower, the canopy shook from side to side and then slowly filled successfully. I couldn't explain it as the temp was warm and I never saw this behavior with this rocket again. It opened at an estimated 500 feet which was fine but not knowing it was going to open in time was scary. Kurt

rstaff3

Oddroc-eteer
I have never flown mine with vent holes. On dozens of flights, I had one that was way late/JIT. The field was totally flat. I blamed it on some sort of snag that rectified itself. I have had more than one rocket land with the chute still folded only to find no obvious tangle/snag when the rocket was recovered.

MALBAR 70

More Rockets Than Room
TRF Supporter
I too had a late opening with my JLCR. The hilly area where we launch may have been the culprit, but I'm not 100% sure. It only happened the one time.

Handeman

Well-Known Member
TRF Supporter
I don't have many flights with my JLCR, but my chutes seem to pop open as soon as the release lets go. I moved the release point down to 30m/100ft. On a "relatively" calm day or one where I don't mind taking a walk, I'll set it to 200 or 300 but only because I don't mind it opening high and having a little longer walk.

Am I doing something that avoids the late opening, or have I just been getting lucky?

billdz

Well-Known Member
Thanks for the replies. Still unclear to me what caused the late deployment. It did not appear that anything was tangled.
@nytrunner: "Where did you get her the CAR?" What's a CAR?

Why does the JLCR only work with motor ejection?

timbucktoo

Well-Known Member
Staff member
TRF Supporter
Global Mod
Why does the JLCR only work with motor ejection?
Who says that? I know lots of people who use it with dual deploy & 2 staging.

billdz

Well-Known Member
"[FONT=&quot]Requires the use of motor ejection"
[/FONT]
https://www.jollylogic.com/products/chuterelease/

noffie79

Well-Known Member
"[FONT=&quot]Requires the use of motor ejection"
[/FONT]
https://www.jollylogic.com/products/chuterelease/
That means that the Chute Release doesn't control any ejection events of the recovery system from the rocket. You still need either the motor ejection or if using it in a dual deploy setup, the ejection that is altimeter based.

markkoelsch

Well-Known Member
I personally have seen more failures of the device than success. Saw four flights today using them, and 1 appeared to have worked correctly. Seems to be a touchy device to get correct.

dhkaiser

Well-Known Member
I personally have seen more failures of the device than success. Saw four flights today using them, and 1 appeared to have worked correctly. Seems to be a touchy device to get correct.
Please explain the failures. Were they the same person? Personally I have seen many deployments and no failures.

rstaff3

Oddroc-eteer
I have flown mine a lot and seen a lot and I have only had one complete failure. That was on a rocket with a heavy cone that fell cone first. The CR was right at the cone and the body flew into the opening chute. Next time I put the CR on it's own leader so it would not be under the falling body.

noffie79

Well-Known Member
I've had many more successes than failures. And I can say that 100% of my failures were from user error. If you follow John's videos on his website, it'll work. No need to reinvent the wheel so to speak.

ksaves2

I've seen and had tangled harnesses that fouled the deployment and sometimes I can't tell because I walk up to the rocket and the chute is lying packed on the ground with the open CR
beside it. Technique of course is not the devices fault. I deploy the chute release up high too so I can get a fix on the trackers. In that case, I like some hang time and am not doing low level deployments like I've seen too many folks do. If there is room to be had at the launch site, no reason to do low level deployments. I've seen many rockets hit the ground with the
JLCR because the fliers set them for 200 - 300 feet.

Another thing is not to pre-prep the chute and have it sitting in the rocket for long periods of time in a tightly packed state. I'm convinced the creases in the canopy can "set"
and delay the opening of it. Even if just sitting overnight. I have been guilty of this in the past and am going to pack a thoroughly talcum powdered chute from here on out
just before launching onsite.

Do not put a "leader line" on a chute protector. That is a piece of kevlar thread with a loop to hold the chute protector and a loop to slide on the harness on the other end. More often than not the kevlar line wraps around the harness and anything else that gets in the way. Thread the harness through the chute protector hole or secure it in one place with a loop in the harness itself (or duct tape). Make sure the chute pack with the JLCR gets clear of the chute protector. Once the charge has blown, no need for the protector to be anywhere near the JLCR chute pack
to interfere with the canopy filling once the CR opens the pack.

All this improves the chances of success. If one has flown a lot of rockets I bet they'll have one that "twists around" the harness on descent. Swivels can help but I've seen some mighty
twisted up harnesses even with swivels inline. I've seen descent videos of some of my rockets that are nauseating. Once the main is out and deployed, then the harness (without swivels) wants to "untwist" in the opposite direction. Kurt

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jd2cylman

Still not Carl... ;-)
TRF Supporter
The one failure I had was user error. I didn't use the shorter rubber band and the shroud lines pulled out of the canopy (still held by the CR) and essentially reefed the chute. As it fell, the shroud lines twisted until the CR let go. By then the lines were twisted enough, the canopy couldn't open.

crossfire

I put in a post in another section but will post it here to. Anyone else having problems with the bands breaking? A friend has had 2 flight with his JLCR and both times band has broke. Today on my flight I had the band break. mine was the 1st flight on the band. Temps were about 30 and my chute and JLCR were protected by nomex chute protector.

rstaff3

Oddroc-eteer
I have had no such issue, although I have only flown it above 50 degrees.

EXPjawa

Well-Known Member
I've had the bands on mine deteriorate after around a half-dozen uses. They developed little cuts and nicks on the edges and eventually failed. At this point, I've used up all of the small bands that were included with the CR and have to get replacements before flying season starts here.

crossfire

Like I said I have had very good luck with JLCR and really like it. For the flight today I installed device last night so all I had to do was turn it on. Maybe being stretched for to all of a time caused the failure. I will try it again in 2 weeks.

John Beans

Founder, Jolly Logic
TRF Supporter
You do NOT need vents.

Chute Release very reliably releases at the set altitude (relative to the ground level where you turned it on, so keep that in mind for hills and valleys).

Of course, if you walk up to it and it's NOT released, and you're SURE you turned it on, then something is up, and send it to me to be checked in our vacuum chamber. But we don't see this problem ever for a unit that's not crashed and broken.

There are a number of reasons your chute may not pop open the instant that Chute Release triggers:

1. Your chute bundle might be a little puffy rather than firm and smooth (the bands get caught in them instead of springing free)
2. Your shroud lines are wrapped around your parachute (put them inside)
3. You blanket stays wrapped around the bundle on the way down

Hope that helps?

HHaase

Siegecraft Electronics
+1 on not prepping the chute TOO far ahead. I've had a few that just seem to stick to themselves if I don't fluff them out if they've been packed for too long. Particularly Estes plastic chutes but seen it a few times with ripstop and other types of nylon. I'm considering maybe starting to give them a light dusting of talc or chalk to keep from sticking.

-Hans

Nathan

☢
TRF Supporter
My JLCR experience :
- Bought one. Didn't work. John Beans sent me a replacement for free.
- Lost it along with the rocket when it came down in a big pond.
- Bought another one.
- Lost it when I forgot to attach the tether.
- Bought another one.
- This one is still working fine. But now I have rockets that I only fly with JLCR, so just to be safe I . . .
- Bought another one.

Nathan,