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Well-Known Member
Nov 22, 2013
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Ok, I learned a hard lesson today on my first flight ever using a JLCR.

Beautiful flight on my Space X Falcon, nose cone ejects perfect, then wait for it, wait for it, wait for it, OH CRAP! She lawn darted. The chute was in tow but never deployed.

Ironically, the lawn dart looked like a perfect Space X Falcon landing and drew cheers from the crowd.

So what was the problem..................I FORGOT TO TURN IT ON.

The manual is very specific, REMEMBER TO TURN IT ON.

However in my case I believe there were two contributing factors.

No. 1, I forgot plain and simple, but here's why. I ran several test, but after every test you have to turn it back on.

No. 2, I believe this is the primary reason I forgot. I purchased a Dino JLCR protector. The protector is well made and does protect the CR. However it makes it a total pain in the butt to turn the CR on, or to verify the CR is turned on. The way the protector fits, you have to put it on the CR before you load the canopy. Then you have to try to pull it down enough to access the buttons, and then you still can't see the lights. So you pull the cover a little further down and it makes the rubber band move. Now you have messed up your pack job.

Subsequent flights, the JLCR worked as advertised. It was a windy day, so I was thankful to have it.

Bottom line, I really like my JLCR, but I would strongly recommend against the cover, at least until it is modified to allow access to the buttons and visibility of the lights. This could easily be accomplished with the addition of a small piece of the pliable clear plastic.


The JLCR open opens momentarily, this has the potential to create two issues:

No. 1 If you have wrapped the CR around your chute in such a manner as to put the "pin" in a slight bind at trigger, it won't release. If at trigger the pin release stayed open it would create an additional chance for the chute to open as it "shakes" around.

No. 2 If the release was not momentary, it would have to be turned on to use. This would eliminate the need to remember to turn it on. You would have to turn it on to use it.

And one more positive, very portable, I used it on 4 different rockets at the same launch. I used a larks head knot to attach it to the shock cord right below the parachute. Again great device but would be even better if you had to turn it on to use it. I know, I know, you can't make things idiot proof........but you can try.
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That sucks, but you've learned a lesson. I don't use the cover, but I have on more than one occasion forgotten that it does indeed revert to being off after a ground test. There have been a couple occasions where I've had to run back out to the pad to turn it back on again prior to launch...
I did the same thing two weeks ago. It worked great on the first flight, so I just attached the band again and stuffed it back in the rocket for a second flight. Now I have a broken fin to repair.

My cover is yellow, but you can't see the lights. In fact the black Velcro covers a portion if not most of the lights of the lights.

I wanted a brightly colored cover as I had several cases of the tether breaking and the bright cover made it easier to find.
The jlcr has pretty good battery life. I always turn mine on and set altitude before inserting in the protector. Then attach to chute. Never had a problem.
The jlcr has pretty good battery life. I always turn mine on and set altitude before inserting in the protector. Then attach to chute. Never had a problem.

I do the same thing. I've got about 40 flights on mine, not a single failure.
IDK. If the Chute Release is working as designed can you say it failed ?
Does it really need a protector? Mine seems unaffected by the hot gases.

I thought that too!
Protector can server 2 purposes:
1) protection from hot gases assuming you dont wrap chute & chute release in nomex
2) high velocity deployment - had an instance where rocket was coming in really fast (no drogue). When Chute Release triggered, the sudden reduction in velocity caused my Chute Release to come apart and the electronics fell out and were never to be seen again. All that was left was the plastic case. The protector will prevent that from happeneing.
Do not wrap the Chute Release around the protector. I've seen where the stiff chute protector remains curled around the chute and it fails to unfurl after release.
Put the chute protector further away from the chute attachment because after the package is blown out you don't need the chute protector.

With a fresh charge that thing can sit on the pad for ages. I had a rocket sit on a pad 45 minutes before it was launched and the JLCR did just fine. Just remember
to TURN THAT PUPPY ON!! Just like making sure that all the electronics are armed for a 2 stage flight.

It wouldn't be that hard to have it stay on after a ground test. (I could literally comment out one line of code that calls the shut down routine.)
BUT, that would require that you remember to turn it off if you weren't about to launch. And it would add a step in the factory (we ground test every unit at least once.)

Thank you for replying. Great device, I really like it. I fully admit it was my boneheaded error.

I really like your suggestion to modify the code so that the device remains on.

This would also make it similar to about every other altimeter out there that requires you to shut it down.

Keep up the good work. I support you goal of no BP. It always makes me nervous that some day an ATF agent having a bad decides to make it bad for a bunch of rocketeers.

One approach might be to make the firmware upgrade optional.

Option A. Shut down after test

Option B. Stay on after test.

Thanks again for responding.
Lowpuller, thank you for having purchased one of our products- we always appreciate it!

We designed the Chute Release Protector so that it can be adjusted while the Chute Release itself is already installed on your parachute. The Protector can easily slide up and down against the slick ripstop nylon fabric on your parachute without it affecting the postion of the rubber band. That gives you access to the control buttons on the Chute Release. Just be sure to put the Chute Release into the pouch before using it.

Here's a video showing how it's done [video][/video]

I've forgotten to arm the Chute Release too, but it's more due to my poor memory :)

We do have an "Arm Electronics" band that helps with remembering this.
I like turning on and arming at the pad as a general rule and practice! If anything goes bad, it is better out there with only a couple people than on spectator row with kids and lookyloos around.

Thanks for responding.

Your product is well made also, however, I am still in general disagreement with the packing method several folks are still using for their parachute.

I say the following based on my experience as a parachute rigger. The lines should never be placed inside of the parachute during packing for two reasons:

No.1, Line Burn, this has been misinterpreted when I have suggested it previously. What I am speaking of is damage caused to the canopy from friction of the lines rubbing against the parachute. Putting the lines on the outside of the canopy, wrapped around it, forces the the lines to come off the canopy before the canopy opens, hopefully eliminating line burn.

No. 2, MOST IMPORTANT, proper opening sequence. The lines should fully deploy and reach line stretch before the canopy inflates to reduce opening shock. Even extreme low altitude BASE jumpers who need super quick openings pack the canopy to open after line stretch.

Based on how I pack my canopy, moving the cover does cause the rubber band to move and does disturb my pack job. As I wrap the rubber band over top of my lines which have been wrapped around the canopy.

Sorry if I sound like a broken record from previous posts, deployment sequence, deployment sequence, de........

Thank you for the video, you did fix one issue for me. I was sliding the Velcro strap under the plastic "handle" on the CR. This added to the parachute disturbance and made in nearly impossible to reinstall the cover if removed when the CR was set, so thank you.

Please keep up the good work and consider some type of "window"