Jolly Logic Chute Release

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I've attempted to use mine twice so far and despite doing a ground test and then folding the parachute back up the same way, on both attempts the chute release released the pin, but the band stuck to the parachute and didn't allow it to open. I have a feeling it has to do with the parachute sitting there wrapped waiting for launch for longer than it waits to get the ground test done. I may have to try this hair ties idea.
 
I've attempted to use mine twice so far and despite doing a ground test and then folding the parachute back up the same way, on both attempts the chute release released the pin, but the band stuck to the parachute and didn't allow it to open. I have a feeling it has to do with the parachute sitting there wrapped waiting for launch for longer than it waits to get the ground test done. I may have to try this hair ties idea.
That problem goes away. Also, sometimes it's hard to tell when that rubber band is going to break - and it usually decides to break when the deployment charge goes off at apogee. I have not had a hair band break. And you can easily tell when it's starting too lose its tension - so change it out.
 
Depending on how the JLCR is attached it is possible that at ejection there will be enough tension on the tether for it to break. You need to be careful to attach it in a way that the JLCR tether does not receive tension before the harness at ejection. This can happen if the tether is connected to the nosecone eyebolt but the chute is connected several inches up the harness.
 
Depending on how the JLCR is attached it is possible that at ejection there will be enough tension on the tether for it to break. You need to be careful to attach it in a way that the JLCR tether does not receive tension before the harness at ejection. This can happen if the tether is connected to the nosecone eyebolt but the chute is connected several inches up the harness.
Best to not tether the JLCR to the nose cone eyebolt. Have seen a few incidences of the JLCR's having their case busted open - and we "surmised" that the chute release had a hard impact against the bolt, bulkhead or shoulder. I had that happen the one time I tethered my Altimeter 2 to the eyebolt. John replaced the case, got it functional - and didn't charge me anything for the work. Great customer service!
 
Best to not tether the JLCR to the nose cone eyebolt. Have seen a few incidences of the JLCR's having their case busted open - and we "surmised" that the chute release had a hard impact against the bolt, bulkhead or shoulder.
I just do a little "loop knot" on my shock cord a few inches below the nc attachment .. hope you know what I mean. Hook it on the loop and its all good.
 
This is how I setup my Chute Release on my Phoenix. The nose weight brings the rocket down nose cone first - and darn fast too. 25 ft. harness and 50" chute. After watching a few tense recoveries I found this arrangement works perfect every time with the Chute Release.


IMG_2662.JPGIMG_2664.JPGIMG_2667.JPGIMG_2669.JPG
 
We have discussed the Power Off issue here before. The worry is someone leaving it on and ending up with a dead battery on flight day.

If we did implement Stay On After Test, we’d also need to implement a Time Out Power Down as well, perhaps after a certain number of hours. That’s not too bad of a trade-off for rocket flyers, given the long battery life, but it would affect long high altitude balloon flights (fairly small group), and other misc uses that might want to exceed that timeout period and would require a timeout extension at altitude.

Any other thoughts are welcome.
 
We have discussed the Power Off issue here before. The worry is someone leaving it on and ending up with a dead battery on flight day.

If we did implement Stay On After Test, we’d also need to implement a Time Out Power Down as well, perhaps after a certain number of hours. That’s not too bad of a trade-off for rocket flyers, given the long battery life, but it would affect long high altitude balloon flights (fairly small group), and other misc uses that might want to exceed that timeout period and would require a timeout extension at altitude.

Any other thoughts are welcome.
Honestly, the way it is now is fine. I bought my unit just a few months after you released it. I have no complaints. I would rather you add more heads-up info in the manual - and make it obvious. Take all these tips, many of which are regularly repeated, and condense the good ones into a cheat sheet for the new person. The Chute Release is simple - simple is good. Do people read manuals? I think most rocketry people do.

You can't prevent 100% failure of a product when humans are involved.
 
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Let me start by saying - I'm not the safety police -or- the Soup Nazi. But I am disappointed. 😞😞😞

My concern is you just admitted to spending an entire day purposefully and knowingly violating the safety code and you seem proud or obliviously or both.

If your jolly rancher (yes I said jolly rancher, I'm just a silly school girl) opens at apogee -:eek::eek::eek: and the rocket drifts into some dry flammable brush 1000 feet from the launch pad.

Here is what could happen:
Big wildfire, lots of acers destroyed, everyone pissed at your irresponsible judgement. (think about the current situation on the west coast)
No soup for you - and no insurance too. Violation of the safety code = claim denied.

Tisk, Tisk, Tisk - You are setting a bad example for all the other kids.

G motor is 1000 feet minimum on the shortest side of the launch site.
More than just a suggestion, these safety codes are STATE LAW in most (not all) of the USA. - Pretty sure PA is included.


View attachment 432361

The site dimensions by impulse category strikes me as a little daft. My 4" Goblin on a G-motor will hit about 600 ft if the winds are zero. A minimum-diameter rocket with low drag can hit 4000 feet on a G-motor. And those are both supposed to have the same field size? That's kind of nutty.
 
The site dimensions by impulse category strikes me as a little daft. My 4" Goblin on a G-motor will hit about 600 ft if the winds are zero. A minimum-diameter rocket with low drag can hit 4000 feet on a G-motor. And those are both supposed to have the same field size? That's kind of nutty.

Yep, NAR and Tripoli are a nutty bunch. The minimum launch site dimensions are there in the safety code and NFPA 1122 and NFPA 1127. Feel free to add as many feet as necessary to safely recover your particular flight and be especially cognizant of potential negative impacts of landing outside of your range.

The safety code:

brad.jpg



[edit] p.s. Big ups for the Chute Release. Makes a long walk shorter.
 
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We have discussed the Power Off issue here before. The worry is someone leaving it on and ending up with a dead battery on flight day.

If we did implement Stay On After Test, we’d also need to implement a Time Out Power Down as well, perhaps after a certain number of hours. That’s not too bad of a trade-off for rocket flyers, given the long battery life, but it would affect long high altitude balloon flights (fairly small group), and other misc uses that might want to exceed that timeout period and would require a timeout extension at altitude.

Any other thoughts are welcome.

I used my Release for the first time 2 weeks ago.
Flawless flight.
Thank you.
 
We have discussed the Power Off issue here before. The worry is someone leaving it on and ending up with a dead battery on flight day.

If we did implement Stay On After Test, we’d also need to implement a Time Out Power Down as well, perhaps after a certain number of hours. That’s not too bad of a trade-off for rocket flyers, given the long battery life, but it would affect long high altitude balloon flights (fairly small group), and other misc uses that might want to exceed that timeout period and would require a timeout extension at altitude.

Any other thoughts are welcome.
Between the two choices:
  • dead battery because I forgot to turn it off after a test
or
  • an unsafe recovery and/or a damaged rocket because I forgot to turn it back on after a test
I think the obvious choice is the first one. If I get to the field and my battery is dead because I forgot to turn it off after a test, that doesn't necessarily prevent me from flying. I can choose a different chute or motor, or simply wait for it to charge, or borrow one from another flyer. But if I suffer a recovery failure because I forgot to turn it on after testing it before flight, the results are far worse. Especially after all the fuss with the magnetic and wifi switches, I would think TRA would look at the JLCR and come to the same conclusion - the fail mode should be safe for the flyer and spectators.

For balloonists or others, it seems a version with the current firmware would have the same problems - forgetting to turn it on after testing it. The auto off could be cancelled if the device detects a significant change in altitude indicating it is in use. Or you could offer two versions.

I think the JLCR is a great product and have used it without failure. But I feel it could be even better if one of the major failure modes could be avoided. Of course no product can be made foolproof, but if the failure mode results in increase safety and fewer recovery failures, that seems to be a decent trade-off. Obviously just my thoughts on it, but based on many observed flights out in the field.


Tony
 
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We have discussed the Power Off issue here before. The worry is someone leaving it on and ending up with a dead battery on flight day.

If we did implement Stay On After Test, we’d also need to implement a Time Out Power Down as well, perhaps after a certain number of hours. That’s not too bad of a trade-off for rocket flyers, given the long battery life, but it would affect long high altitude balloon flights (fairly small group), and other misc uses that might want to exceed that timeout period and would require a timeout extension at altitude.

Any other thoughts are welcome.
How about a small beeper?

Additional cost yes, but no doubt that the Chute Release is ON and armed for launch.
 
I haven’t used it, but based on the modes of operation described, I would also preferred to have it stay on after testing vs. shut off. I generally prefer devices that stay on unless I manually turn them off; the exception is power down after extended periods of idle time.
 
Yep, NAR and Tripoli are a nutty bunch. The minimum launch site dimensions are there in the safety code and NFPA 1122 and NFPA 1127. Feel free to add as many feet as necessary to safely recover your particular flight and be especially cognizant of potential negative impacts of landing outside of your range.

The safety code:

View attachment 432450



[edit] p.s. Big ups for the Chute Release. Makes a long walk shorter.

FWIW, I note that the OP didn't say (and hasn't said yet) that the dimensions were smaller than the safety code - just smaller than he felt they should be. Per JFT's thought - If I were heading to 4000', I would feel quite uncomfortable with a 1000' field, certainly with deployment at apogee (but I'm a very inexperienced noob!). Still, I thank Sabrina, JFT and samb for bringing all these aspects out. I've learned something more about this sport! I will add, safety is PARAMOUNT.
 
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Per JFT's thought - If I were heading to 4000', I would feel quiet uncomfortable with a 1000' field (but I'm a very inexperienced noob!).

Yeah, that's exactly my point, The flat "you need this much space for this engine size" doesn't make a lot of sense when your max altitude can vary so much.
 
Personally, for a good safety margin, I would want a field 1.5x times your max altitude (assuming single deploy).
 
Yeah, that's exactly my point, The flat "you need this much space for this engine size" doesn't make a lot of sense when your max altitude can vary so much.
I wonder if it's based on power available for an explosion? Insurers often think of things from different angles than we do, such as what are all the failure modes.
 
...
Still, I thank Sabrina, JFT and samb for bringing all these aspects out. ...

Don't thank me for hijacking a JLCR thread ! 🙃 Use as directed and enjoy shorter recovery walks. Anyway the minimums are the minimum; lots of reasons why you'd want a bigger area. Percent of max expected altitude is in the high power code and no reason you couldn't apply it across the board.
 
Food for thought: Assume a 20 ft/s descent rate. At 1000 ft, this is 50 seconds of descent. With a constant 10mph wind (=~ 15 ft/s), the total drift away from point of launch is 750 ft.

Almost every rocket I've launched does not go perfectly vertical. Here are the lateral distances for a 1000 ft apogee at various angles:
1 deg = 17 ft
5 deg = 87 ft
10 deg = 176 ft
20 deg = 363 ft

If your rocket takes a 20 deg turn and you have a 10 mph wind in the same direction, it's going to land about 1000 ft away. Launch angle and wind are huge for your recovery zone determination. This is one reason I have yet to launch my 3-stage Microsonde III. The last stage has a slow descent, and it's highly likely to make a trajectory change due to wind or inter-stage forces. Only gonna launch that in a big field on a day with no wind.
 
Our stuff doesn't explode. Setback distances are for overpressure, field size is for recovery area.
Oh yeah, I understand that. But an insurer or the fire protection folks are likely to say, "it's not supposed to explode, but if it does..." The fact that these limits are in the NFPA rules made me think that perhaps they were concerned about flaming debris from a burst engine casing or something. I was surprised, on my first BAR launch a few weeks ago, my first launch ("Biride" on an A10-03T) blew the nozzle out of the casing and bounced it across the field; it was like a firecracker!
 
I would rather you add more heads-up info in the manual - and make it obvious. Take all these tips, many of which are regularly repeated, and condense the good ones into a cheat sheet for the new person. The Chute Release is simple - simple is good. Do people read manuals? I think most rocketry people do.

You can't prevent 100% failure of a product when humans are involved.

You mean like the User Guide? ;)

guide.jpg
 
You mean like the User Guide? ;)

View attachment 432559
Yup. Just need to expand on it. I know you have FAQs on the altimeters, but I don't know about the chute release.

I regularly hear how people do a test - and then forget to turn the Chute Release back on. I don't think you point that out in the manual. It's just these little things that lead to a recovery failure.
 
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Yeah, that's exactly my point, The flat "you need this much space for this engine size" doesn't make a lot of sense when your max altitude can vary so much.
It is more to do with safety relating to the amount of energy contained in the motor, and being protected from a takeoff event (cato, land shark, etc). It is a minimum distance and a responisble flyer will have sufficient space for their flight, be it low or high altitude.
 
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