Sneak Peak: Jolly Logic's Easy Dual Deployment

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After posting that question, I thought about it and realized that many high altitude motors would be plugged. I guess I have just been thinking about some of my lower test flights for the near term. But you are right, Tim, ultimately high altitude flights like Jim does will require an electronic ejection charge. But it looks like the CR is going to make everything after that charge a lot easier.

Planning to use my CR for the first time tomorrow.
 
Hi John
Just to let you know I used the JLCR to today. The chute was a 36" flat chute in a LOC Mini Magg. Motor a 38mm CTI H400 VMax. It worked perfect. Very easy to use. I had 5 flyers come up to me after the flight and asked about the release. Can't wait to use it again. Sure beats the long walks, and will be great for smaller launch sites.

Gary
TFRLLC
 
I made 5 flights today with Chute Release, all quite successful. I flew an additional 2 flights, but those were small mod rocs that the CR simply didn't fit into. But if John ever develops a more compact model that fits in, say, a 24mm tube, I'll be among the first in line...
 
crossfire said:
How big of a chute has anyone used so far?
Click to expand...

I have used it on 30" and 36" elliptical chutes so many times that I stopped counting since it hasn't failed me yet. Some apogee events as high as 3K feet.

Of note, I fold and roll my parachutes the same way no matter whether I'm doing a standard deploy or a CR deploy. I fold as per the Fruity Chutes method.
 
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Six more flights yesterday w/ Chute Release, all 100% successful. A number of other folks took notice too and were impressed with the little device.
 
I used CR on a ~50" Madcow chute in my 4" Nike Smoke on Friday (Madcow calls it a 50" chute but when I measured it I got 56"), ~6.5 lbs on the pad. First time flying the rocket and CR, everything worked perfectly. Had it set for 500' and both the A3 and TRS I flew showed the descent slowed by around 435'. I also used a 18" drogue attached to the NC and only flew to ~1250' for its first flight (I would say low and slow, but it was an H550ST so it was low & pretty fast). My usual chute bundle is to fold the chute then roll the lines around it, in this case I put the lines inside the chute half-way through folding it (once I had done all of the folds to reduce the diameter, but before I started folding it from center to opening to reduce the folded length). This was after successful "pull testing" using this folding method (and of course successful release testing as well). Used a single one of the larger bands provided with the CR, was a bit tight but no band damage afterwards. Only thing I think I'll do different next time is I had the CR's tether around one of the chute lines above where I knotted them together for the quick-link, next time I think I'll loop it below the knot, it did shift slightly up the line and wrap itself around a few of the lines, far from the chute so it didn't affect the chute opening but I'd rather ensure it can't slide up and make things worse in the future.

NikeSmokeCR.jpg
 
One thing I learned about the JLCR this weekend - it can handle a splashdown. My rocket landed about 5-6 feet on the wrong side of the shore of a pond at our launch site. I hustled over to it, and pulled it out as quickly as I could. As soon as I got back to my table, I opened the case, disconnected the battery, dried as much water as I could, and left it in the sun for the rest of the day. When I got home, I put it in a zip-loc ESD bag with a desiccant pack for a couple of days. I just tested it (both self test and in a vacuum jar), and it works as expected.

The unit was submerged for about 30 seconds, and I had it opened and dried within 5 minutes of splashdown. What likely saved it, is that the thing turns off once the chute is released.
 
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AlfaBrewer said:
One thing I learned about the JLCR this weekend - it can handle a splashdown. My rocket landed about 5-6 feet on the wrong side of the shore of a pond at our launch site. I hustled over to it, and pulled it out as quickly as I could. As soon as I got back to my table, I opened the case, disconnected the battery, dried as much water as I could, and left it in the sun for the rest of the day. When I got home, I put it in a zip-loc ESD bag with a desiccant pack. I just tested it (both self test and in a vacuum jar), and it works as expected.

The unit was submerged for about 30 seconds, and I had it opened and dried within 5 minutes of splashdown. What likely saved it, is that the thing turns off once the chute is released.
Click to expand...

Glad your CR pulled through.
 
John Beans said:
That is probably "best demonstrated practice." I doubt it can be done better. Everyone. This is how to do it.
Click to expand...

I've learned to handle wet electronics the hard way. One thing I would do differently, is to open the case immediately and disconnect the battery. The locking tabs you have on there are big enough to open with your fingers. I might have done this, but can't really remember, as I was kinda focused on saving the chute release and the rocket it was attached to.

Having opened mine up and taken a look at the internals, this is one elegantly designed piece of hardware. It is obvious you spent a lot of time on the mechanical side of things, not just the electronics. There's not any wasted space. It's also clear a lot of design for manufacturing/assembly effort went into this device. My hat is off to you.
 
I made 4 flights with CR yesterday, only 3 successfully deployed however. On the last flight (my last flight of the day due to weather), separation occurred at appogee like normal, and the rocket dropped. But when it got to 300', nothing changed. It fell horizontally and landed in the grass, so no damage occurred. When I found it, the CR was released, however, the parachute was still folded and the CR was on top of it. That kind of leads me to believe that it released on landing, rather than at the set altitude. Otherwise, how could the chute and CR be sitting on the ground in the same condition as they were when prepped?

Now, I know I made a point of actually turning it on, the battery was showing 4/5 charge, I performed the ground checks at set up, and everything was free to move in the body tube (it did separate afterall). However, there was an awful long delay between prepping and launching due to waiting in line for safety check, then waiting in line for a pad, then the LCO eventually getting to my pad.

So, my question is: does the device time out to save the battery after a period of inactivity, making it necessary to recheck that its on when placing on the pad? Also, is it possible for it to have released on impact as I surmised?

I will offer that every time the LCO announced that a flight had the Chute Release, and then it did its job, people were impressed. I heard a lot of buzz about maybe needing to pick one up. Fortunately, the flight where it didn't work, no announcement about it was made...
 
I've seen that happen before. Did you ground test? Was the band tight enough to leap off when released? Was the band stuck in folds?

Fully charged it will stay on for days.
 
Well, as I said, I did run the ground checks. I've gotten in the habit of 1) cycling it make sure the pin pops out, 2) swinging/shaking to mke sure the chute doesn't slip out, & 3) puffing the business end (which can taste bad) to make sure that the cone will slide when pressurized. Not sure about being stuck in the folds of the chute; nothing like that jumped out at me, but it didn't occur to me to check either.
 
I'd venture a guess that it was indeed stuck in a fold in the chute. I've done the suggested ground tests each flight and have had a 100 percent success rate.
 
Launched a couple Estes PS II rockets tonight. Used my Jolly Logic Chute Release on my Sahara. I positioned the camera above the transition so I could watch the CR in action. Two more fantastic flights because of Jolly Logic. https://youtu.be/NTH6pVTRw6M
 
noffie79 said:
Launched a couple Estes PS II rockets tonight. Used my Jolly Logic Chute Release on my Sahara. I positioned the camera above the transition so I could watch the CR in action. Two more fantastic flights because of Jolly Logic. https://youtu.be/NTH6pVTRw6M
Click to expand...
Wow, that is great video - it shows one of the biggest issues in recovery - the twisting of the recovery harness. Even though the swivels are clearly visible you can watch the recovery system twist itself up into a much shorter system. I don't know what the answer is but on dual deploy you can see how that can really cause an issue. And of course this is unrelated to the CR, it seems to happen routinely. I've tried many things to prevent it on my own systems without much luck.

Just an observation based on the really excellent video. Really cool to see the CR in action.


Tony
 
manixFan said:
Wow, that is great video - it shows one of the biggest issues in recovery - the twisting of the recovery harness. Even though the swivels are clearly visible you can watch the recovery system twist itself up into a much shorter system. I don't know what the answer is but on dual deploy you can see how that can really cause an issue. And of course this is unrelated to the CR, it seems to happen routinely. I've tried many things to prevent it on my own systems without much luck.

Just an observation based on the really excellent video. Really cool to see the CR in action.


Tony
Click to expand...

Thanks for the comments Tony. Yes, the shock cord twisting is an issue. Someone gave me the idea of placing a swivel inside the booster and then attaching the cord to that. I think that's a great idea and should alleviate the problem.
 
noffie79 said:
I'd venture a guess that it was indeed stuck in a fold in the chute. I've done the suggested ground tests each flight and have had a 100 percent success rate.
Click to expand...

I'm having a hard time imagining how the band would get stuck in a fold in such a way that 1) prevents the chute from mostly opening and 2) doesn't shake out in the fall. I had more or less the same thing happen on Monday with my Der V-3. In this case, the CR was not still bundled with the chute on the ground, and the chute was partly unfolded. See below:
27327693411_2ac53f4044_b.jpg


But even such, it never opened. I thought perhaps that I set it too low previously and the chute had simply not had time to inflate, so I raised the release altitude on this flight here. I have, as I said, also performed the suggested ground tests for each flight, but now am on my third flight (of 26) that did not open. So something is going on that I'm missing or doing incorrectly. Is it possible that the CR is somehow not always getting a good read on the altitude? Is there a sample port in the case that I might be inadvertently blocking? If the band is getting caught somehow, what can I do to prevent it? Right now, it seems like a real neat device that I can't yet fully trust. It has worked well close to 90% of the time. But that other 10% concerns me. John, I am absolutely not trying to bash your product. I just want to understand better what's going on so I can improve my results.
 
EXPjawa said:
I'm having a hard time imagining how the band would get stuck in a fold in such a way that 1) prevents the chute from mostly opening and 2) doesn't shake out in the fall. I had more or less the same thing happen on Monday with my Der V-3. In this case, the CR was not still bundled with the chute on the ground, and the chute was partly unfolded.

But even such, it never opened. I thought perhaps that I set it too low previously and the chute had simply not had time to inflate, so I raised the release altitude on this flight here. I have, as I said, also performed the suggested ground tests for each flight, but now am on my third flight (of 26) that did not open. So something is going on that I'm missing or doing incorrectly. Is it possible that the CR is somehow not always getting a good read on the altitude? Is there a sample port in the case that I might be inadvertently blocking? If the band is getting caught somehow, what can I do to prevent it? Right now, it seems like a real neat device that I can't yet fully trust. It has worked well close to 90% of the time. But that other 10% concerns me. John, I am absolutely not trying to bash your product. I just want to understand better what's going on so I can improve my results.
Click to expand...

Deployment has several steps that all need to happen to work well. You need proper ejection, then the release has to trigger, then the chute needs to unfold.

Sounds like you're not getting stuck in the tube (congrats, that's what usually gets me, by the way). And it sounds like Chute Release is opening. What's happening is that you're not getting inflation after release.

How do you fold your chutes? Have you tried other techniques, or do you usually fold the same way each time? I have found that folding the shrouds inside the chute works best for me, though I know others have developed techniques which differ, especially for smaller chutes. For instance, in the smallest 38mm rockets, you just wrap around the base of the chute (not a folded up chute). During tumble, the chute is stretched out upward with Chute Release just holding the base of the canopy together. The chute acts like a drogue.

I also have heard that there are cases where a fire blanket can get in the way a bit by preventing the slipstream from peeling the chute open.

When I was testing Chute Release, I would fly it with a recording altimeter so that I could improve my folding technique each time and get the quickest inflation possible. As the instructions note, you should plan for 50-150 feet of descent for the chute to inflate. With practice, you can get down to 50 feet (or less) pretty quickly. Experiment, and read about techniques others have developed for themselves. Some are worth trying yourself, even if they seem strange to you at first.

To me, the holy grail is to have very reliable, very low deployment with an oversized chute. In that way, you drop down out of the wind, open near the ground, and land very softly. To anyone who doesn't yet have experience with Chute Release, that can sound disturbing. But once you've gained confidence in your folding (and of course, in Chute Release), there's a certain joy in planning and executing and a more optimal landing than the old way--which either involved a "too small chute that won't drift so far" or a "soft-landing chute that I will have to chase for a mile."
 
John Beans said:
Deployment has several steps that all need to happen to work well. You need proper ejection, then the release has to trigger, then the chute needs to unfold.

Sounds like you're not getting stuck in the tube (congrats, that's what usually gets me, by the way). And it sounds like Chute Release is opening. What's happening is that you're not getting inflation after release.

How do you fold your chutes? Have you tried other techniques, or do you usually fold the same way each time? I have found that folding the shrouds inside the chute works best for me, though I know others have developed techniques which differ, especially for smaller chutes. For instance, in the smallest 38mm rockets, you just wrap around the base of the chute (not a folded up chute). During tumble, the chute is stretched out upward with Chute Release just holding the base of the canopy together. The chute acts like a drogue.

I also have heard that there are cases where a fire blanket can get in the way a bit by preventing the slipstream from peeling the chute open.

When I was testing Chute Release, I would fly it with a recording altimeter so that I could improve my folding technique each time and get the quickest inflation possible. As the instructions note, you should plan for 50-150 feet of descent for the chute to inflate. With practice, you can get down to 50 feet (or less) pretty quickly. Experiment, and read about techniques others have developed for themselves. Some are worth trying yourself, even if they seem strange to you at first.

To me, the holy grail is to have very reliable, very low deployment with an oversized chute. In that way, you drop down out of the wind, open near the ground, and land very softly. To anyone who doesn't yet have experience with Chute Release, that can sound disturbing. But once you've gained confidence in your folding (and of course, in Chute Release), there's a certain joy in planning and executing and a more optimal landing than the old way--which either involved a "too small chute that won't drift so far" or a "soft-landing chute that I will have to chase for a mile."
Click to expand...

John, I couldn't agree more with the last part of your statement. Once I had some practice with CR, I started gaining confidence in it. I decided I wanted to push things farther than I had before. I decided I would launch my L1 rocket, a LOC IV that weighs in at 48 oz on a 38mm motor to ~2300ft. Winds were between 10-15 mph. I used a 50" chute. Without the CR, a 48 oz rocket with a decent rate of 15.87 ft/sec in a 12 mph wind has an estimated drift distance of 2500 ft. But with the CR, I had to walk about 300 ft to retrieve my rocket. I couldn't be happier with this product. It has literally changed everything about the way I launch. I have a video of the launch I mentioned. I'll have to upload to YouTube and provide the link later.
 
I have had one flight where the chute got tangled. Luckily it extended fully and partially worked. I basically folded it per John's videos and then over one time sideways to thicken the bundle. I may have ended up with the band in the direction of the shroud lines instead of perpendicular to them. Hard to say but at least the rocket recovered with no damage.
 
I've pretty much folded the chute the same way with each flight that's used the CR. Basically, I fold the canopy into quarters, fold the shroud lines on top of it, then fold the point of the canopy over the lines. Then its basically burrito rolled up fairly tightly. I put the CR around it and cycle it to make sure the band will pop off smartly. There's been some variation depending on how small I had to get the bundle to fit in the tube; a lot of the rockets I've used it with have 1.6" tubes. Of the two where it came out but didn't open, one was in BT60, so it had to be pretty small, but the one pictured above is BT80 (2.6"), so I didn't have to be as fussy about getting it rolled tight. Also, this was a standard weight (1.7oz) nylon chute, though most of the others I use are the lighter thin-mil nylon. Could the variation come from where I've attached the CR to the rocket? I've put it on the shock cord, the swivel, on a shroud line, depending on the set of the rocket in question.

As a side note, I've gone through a number of the smaller bands. As noted previously, I'm still seeing them get nicked and cut (even though I wrapped the sharp ends of the split ring), so they eventually break when installing or switching sizes. Is the small size something that I can get replacements for readily?
 
EXPjawa said:
As a side note, I've gone through a number of the smaller bands. As noted previously, I'm still seeing them get nicked and cut (even though I wrapped the sharp ends of the split ring), so they eventually break when installing or switching sizes. Is the small size something that I can get replacements for readily?
Click to expand...

We'll offer replacement packs shortly, for both sizes of bands. And more recent bands have even higher latex content, so you may see some improvement there.

I think you maybe should start experimenting with more of a z-fold design on those chutes, or at least some folding technique which more heavily relies on the band to hold it together. For instance, when the band pops off on a table test, the chute should "fall open," rather than still just sit there rolled up tightly. Also, consider the "skirt luffing" technique as well for smaller rockets like you discuss here. See BECs post about big bertha-sized rockets, for instance.
 
Rick,

It looks like you're using flat chutes. Try Kevin's method here. I've never had a parachute fail to inflate using this folding method. You can deviate slightly to give a little more material to roll up, but the Z fold is the key. The chute is basically forced to pop open by the folds.
 

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