Jolly Logic’s Chute Release and HPR

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jahall4

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Now that Jolly Logic’s Chute Release has been out for a while how many of you have used it on HPR (at least L1 single event flights) ?
 
I have, for several L1 type flights. This includes rockets that are between 2.6 and 4" diameter and up to 45" chutes. Others have used with much larger ones though.
 
Separate of certs, I've done several flights with a 12" drogue, and 50" and 48" main chutes in a 40 oz 4" rocket on H motors, as well as a 3" fiberglass rocket to 3900' with an 18" drogue and 50" main. Chute Release worked great on all flights!
 
I use it on my MDRM every flight, regardless of MPR or HPR motor. Biggest thing I've put in it is an I204.
 
Biggest thing I've put in it is an I204.

This is good stuff to hear. Prior to starting this thread I really had no doubt it would work fine for us on this project https://www.facebook.com/TheMarvinWrightRocket/# (I motor, 60” inch chute), but then I stumbled into this on Apogee’s web site:

… we do not recommend flying it on high power rockets … The NAR's position is to err on the side of safety (we at Apogee Components agreee completely).

Which sort of infers NAR does not advise using them for HPR and goes on to suggest that only dual deploy is acceptable for HPR. The irony here is that there appears to be no reason why a JL CR can’t be used to dual deploy a main on the same harness as
the drogue making DD easy on a rocket with single event recovery.
 
The only reason is that people are overly cautious, though the conspiracy theorist might argue that some folks might want to protect the business of selling expensive DD altimeters, sleds, black power, charge wells, etc. Probably hogwash. But still, as far as I'm concerned - and likely a lot of people that are happy with this product, there is nothing really to limit the use of the product withing practical limits. IMHO, this makes "old fashioned" DD obsolete in the mid-sized L1-L2 rocket category, and makes all sorts of existing rockets effectively DD capable that never could've been before. I just bought a MAC Performance Scorpion, and specifically stuck with the less-expensive single-deploy version because there's no compelling reason to buy the DD version...
 
The only reason is that people are overly cautious, though the conspiracy theorist might argue that some folks might want to protect the business of selling expensive DD altimeters, sleds, black power, charge wells, etc. Probably hogwash. But still, as far as I'm concerned - and likely a lot of people that are happy with this product, there is nothing really to limit the use of the product withing practical limits. IMHO, this makes "old fashioned" DD obsolete in the mid-sized L1-L2 rocket category, and makes all sorts of existing rockets effectively DD capable that never could've been before. I just bought a MAC Performance Scorpion, and specifically stuck with the less-expensive single-deploy version because there's no compelling reason to buy the DD version...

No, it doesn't make DD obsolete in L1/L2 sized rockets. That size is very cost effective for one to learn the techniques of DD before moving one to larger projects. I do agree the CR does open up using different (ie. shorter) rockets for a staged deployment. Keep in mind one will be limited as to the length of delay that is available and the size of the parachute. Really large chutes might not be amenable to the CR.
Also, punching up a small rocket without a tracker is risky as it can be lost with a sight unseen flight.

"… we do not recommend flying it on high power rockets … The NAR's position is to err on the side of safety (we at Apogee Components agree completely"

I agree the statement above is complete balderdash and stupid. Kurt
 
I do agree the CR does open up using different (ie. shorter) rockets for a staged deployment.

And that's exactly why we need it for our project.

I'd argue anything that makes it easier to launch larger and higher quicker is good for the hobby as it becomes more accessible to more rocketeers.
 
The problem is not the chute release, it is how people use it.
They use it together with motor ejection and think they have now the safety of normal DD, which they do not have because they have no backup for the drouge event.

If you use a backup electronic and two chute releases for redundancy you are fine.
 
The problem is not the chute release, it is how people use it.
They use it together with motor ejection and think they have now the safety of normal DD, which they do not have because they have no backup for the drouge event.

If you use a backup electronic and two chute releases for redundancy you are fine.

Backup to the apogee/drogue charge is helpful. I use a lot of nosecone sleds (Attebery makes some really nice ones)
 
The problem is not the chute release, it is how people use it.
They use it together with motor ejection and think they have now the safety of normal DD, which they do not have because they have no backup for the drouge event.

If you use a backup electronic and two chute releases for redundancy you are fine.

Two chute releases? How do you figure this would work? If one doesn't release, the chute will still be wrapped in a rubber band.
 
On my of my flights this year for what ever reason motor ejection was very late. I think the chute release opened inside the rocket. When ejection did happen chute opened right away saving the rocket. I do not think chute was shook loose from hard ejection. It looked like chute opened right out of the tube. I would think this could have happened.
 
Two chute releases? How do you figure this would work? If one doesn't release, the chute will still be wrapped in a rubber band.

Use two Chute Releases and two short rubber bands to make one loop around the parachute. First CR attached to first rubber band attached to second CR attached to second rubber band attached to first CR.

I would be interested to know what John Beans thinks about this configuration. I'm thinking about doing this for the upscale Onyx that I'm building which will fly on 54mm L2 motors. It will have redundancy for the apogee deployment (both nosecone altimeter and motor ejection) but I would also like to have redundancy for the chute release.
 
John has recommended that as a method for redundancy. If one CR fails, the chute will still get released.
 
Use two Chute Releases and two short rubber bands to make one loop around the parachute. First CR attached to first rubber band attached to second CR attached to second rubber band attached to first CR.

I would be interested to know what John Beans thinks about this configuration. I'm thinking about doing this for the upscale Onyx that I'm building which will fly on 54mm L2 motors. It will have redundancy for the apogee deployment (both nosecone altimeter and motor ejection) but I would also like to have redundancy for the chute release.

In the other thread there was at least one person who certified L3 with the dual chute release configured like that. It should work just fine. My only concern is an 8'+ parachute is starting to get a little large for a single band wrap.
 
And that's exactly why we need it for our project.

I'd argue anything that makes it easier to launch larger and higher quicker is good for the hobby as it becomes more accessible to more rocketeers.

Yeah, but they'll ultimately lose them without a tracker. Plus if a long enough motor delay isn't available, it would negate the ability to use that motor. I have a rocket with a nosecone GPS tracker that fits an I motor with ease but
the simulations show that even the longest delay available is too short. That said, plenty of H motors available that are usable and I agree the CR opens up a lot more doors. Saying it shouldn't be used in HPR is just some lawyerly
covering of one's derriere. Kurt
 
Ahhhhh, That's a pretty big chunk of change there for redundancy. For redundancy they would be connected in a serial fashion to each other. It's akin to using two explosive cutters connected to the same ziptie holding the chute folded.
Only one has to successfully cut the tie for the chute to be released. To do that with a CR one would have to have enough room to stuff it all in. Kurt
 
I just received my first CR yesterday, very nice packaging and quality of finish; that is where my review and opinion stops unfortunately.

I can tell you where I see using it based on my fleet. I have some MPR that have the potential to fly much higher, but I try to keep them under 1500AGL due to recovery limitations. I am hoping the CR will allow my to dip into my motor inventory and fly some of the motors that will put these rockets up to the 2500AGL range and still allow for a reasonable recovery.

Beyond the MPR stuff I do have some HPR rockets that I retrofitted for DD, all using a nosecone AV bay and primarily cable cutters, although I also experimented with C02 and an ARRD. I never felt comfortable enough or that the solutions were practical for these rockets, but I see the CR being the perfect solution. In all of these cases I will still use electronic altimeter based apogee, as I still see it as the best option for that particular event, although the thought of never having to deal with BP again is a nice thought.

I am pretty sure that as I gain some experience and read about everyone else's experience, that I will expand my usage of the technology as will the hobby in general. It will be interesting to see CRv2, which I am sure John already has a list of things to change/add...hopefully including making it more narrow even if it is longer.

I read about someone wanting to use it for their L1, L2 and L3.
 
I would like to see the JLCR with at least the function of the ALT1

The picture John posted previously as a teaser for the AltimeterFour looked so small that I suspect it could be integrated into something like the CR. That would be nice.
 
If by "integrated with" you mean "epoxied to" then I think we already have a rough outline of how to accomplish that :p
 
Adding recording functionality to Chute Release seems feasible.

Fantastic... I've been using my JLCR on almost every flight, and relying on a nosecone sled with altimeter for recording... Would be great to have both in one unit.
 
Adding recording functionality to Chute Release seems feasible.

Do you see any possibility of making the package smaller, even if you have to lengthen the package in favour of losing a few mm of width? I see this as an excellent option for a 38mm MD but I think you will have to be creative in packing the chute, which any width reduction would help or at least be a bit more forgiving.
 
The smaller next generation Chute Release mechanism is like designing a watch mechanism. Requires a ground-up servo design. Fun!
 
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Yeah, but they'll ultimately lose them without a tracker. Plus if a long enough motor delay isn't available, it would negate the ability to use that motor. I have a rocket with a nosecone GPS tracker that fits an I motor with ease but
the simulations show that even the longest delay available is too short. That said, plenty of H motors available that are usable and I agree the CR opens up a lot more doors. Saying it shouldn't be used in HPR is just some lawyerly
covering of one's derriere. Kurt

No device or technology will ever replace adequate preparation or overcome ignorance (hey that's a pretty good quote!), but this device will reduced the number of rockets lost. And as we discovered yesterday has benefits beyond just keeping your walk short that I have never seen articulated.
 

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