Who Used Chute Release for L1, L2, or L3?

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Vombatidae

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I didn't have my JLCR in time for my L1 cert, but I have flown in twice in my L1 cert rocket.

The first time, I was flying with no vent hole in the airframe (having read it's not required), set the JLCR for 500', and watched it release with no tangles... shortly after hitting the ground. Fortunately, there was no damage.

The second time, 45 minutes later, I drilled a 1/4" vent hole, and everything worked perfectly.

My theory is that with a relatively small airframe volume and a tight nose cone, the pressure spike caused by inserting the nose cone interfered with the barometric value used for ground level. I would welcome additional input.
 

billdz

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I didn't have my JLCR in time for my L1 cert, but I have flown in twice in my L1 cert rocket.

The first time, I was flying with no vent hole in the airframe (having read it's not required), set the JLCR for 500', and watched it release with no tangles... shortly after hitting the ground. Fortunately, there was no damage.

The second time, 45 minutes later, I drilled a 1/4" vent hole, and everything worked perfectly.

My theory is that with a relatively small airframe volume and a tight nose cone, the pressure spike caused by inserting the nose cone interfered with the barometric value used for ground level. I would welcome additional input.
Did your chute eject from the rocket? As the JLCR does not release the chute until after ejection, when it is in the open air, it's hard to see why a vent hole in the airframe would affect the JLCR's performance.

That being said, in my experience the JLCR has likewise failed to release the chute until impact on at least 2 occasions out of 20 or so, not sure why.
 

Vombatidae

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Did your chute eject from the rocket? As the JLCR does not release the chute until after ejection, when it is in the open air, it's hard to see why a vent hole in the airframe would affect the JLCR's performance.

That being said, in my experience the JLCR has likewise failed to release the chute until impact on at least 2 occasions out of 20 or so, not sure why.
Yes, the bundled chute was out at apogee - made a pretty effective drogue. :)

To elaborate on my theory, the pressure inside the airframe at the time of the first launch was probably significantly above the ambient ground level barometric pressure, and I'm speculating that could interfere with the 500' AGL detection.
 

Performance nut

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Here are some photos of the rocket I'm working on now. Its almost exactly the same design as the one from the video (I guess that ebay is at home after all). The runcam2 has worked out pretty good for me. No complaints. Let me know if you have any questions.

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Did you print your own sled? Pretty slick setup you got there. I have been thinking of something similar from the same company (different lens) and wondered how the lens holds up without a shroud.
 

BryRocket

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Yes, the bundled chute was out at apogee - made a pretty effective drogue. :)

To elaborate on my theory, the pressure inside the airframe at the time of the first launch was probably significantly above the ambient ground level barometric pressure, and I'm speculating that could interfere with the 500' AGL detection.
When did you turn on the JLCR and set the release elevation? That is when it would take the baseline reading I’d assume. I’m guessing you did that before stuffing it into the rocket right? Are you thinking that, after you set the JLCR, when you pushed the nosecone in the rocket it raised the pressure and messed with the reading?


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BryRocket

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Did you print your own sled? Pretty slick setup you got there. I have been thinking of something similar from the same company (different lens) and wondered how the lens holds up without a shroud.
The sled is from Andrew at Additive Aerospace. His stuff is awesome.

The lens is great without a shroud. I epoxy a piece of polycarbonate to the back of the lens so I can mount it a few different ways.


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Vombatidae

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When did you turn on the JLCR and set the release elevation? That is when it would take the baseline reading I’d assume. I’m guessing you did that before stuffing it into the rocket right? Are you thinking that, after you set the JLCR, when you pushed the nosecone in the rocket it raised the pressure and messed with the reading?


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Exactly. I powered it up, got a solid green led at 500', and popped it in. I was first up on that rack, so it flew only a couple of minutes after arming.
 

billdz

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Exactly. I powered it up, got a solid green led at 500', and popped it in. I was first up on that rack, so it flew only a couple of minutes after arming.
Interesting theory but I doubt that is the reason the JLCR failed to release, hopefully John Beans will comment. After my first fail with the JLCR, someone suggested the cause was the lack of a vent hole in the airframe, but John told me no vent hole was needed. See also: https://www.rocketryforum.com/showthread.php?134081-Jolly-Logic-Chute-release-Question (ejection charge pressure does not cause false reading).
 

o1d_dude

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After spending a month exposed to sunshine, wind, and rain on Snow Ranch, my lost/found Chute Release charged up and works perfectly. It was enclosed in a Dino Chutes JLCR sleeve that faded from bright red to a pale orange also.

Hats off to John Beans for crafting a very durable device.
 

snrkl

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When did you turn on the JLCR and set the release elevation? That is when it would take the baseline reading I’d assume. I’m guessing you did that before stuffing it into the rocket right? Are you thinking that, after you set the JLCR, when you pushed the nosecone in the rocket it raised the pressure and messed with the reading?


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I’ve heard this trigger the servo release in a JLCR when the nose cone went on - the other member couldn’t figure out why he kept hearing the JLCR open in the pad while prepping and asked us what we thought was happening.

Told him to vent the body and 30sec of cordless drill work later, JLCR worked flawlessly.
 

smugglervt

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Got my L2 last Sunday with a Wildman 4" Patriot with a CTI J280ss and JLCR set at 600'. Apogee at 2,750 and JLCR worked perfectly.
 

rocketman300

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I used my chute release in my Madcow patriot for my level 1 and I plan to use it for my level 2 as well.
 
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OverTheTop

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If you’re using motor deployment, put your motor in after putting on your nosecone so you don’t cause a pressure spike by inserting the nosecone.
Doesn't putting in the motor also cause an increase in pressure in the chute bay? I know it does in my rockets. It is a big long piston going up the kilt.
 

Steve Shannon

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Doesn't putting in the motor also cause an increase in pressure in the chute bay? I know it does in my rockets. It is a big long piston going up the kilt.
Yes, you’re absolutely right, especially if the motor fits tightly and you insert it quickly. Most motors don’t fit nearly as tightly as nosecone shoulders though, so a spike might be avoided by slowly inserting the motor.
 

Normzilla

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Hey JB, anything new?

Trackers, redesigns, need a Guinea pig?


Nathan
 

Homer_S

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Success!

Certified L1 today with Chute Release in an SA-14 Archer at Bong on an H115DM-8.

Altimeter 3 says... Altitude: 2110', Initial Descent: 34 fps and Landing: 15 fps.


Now with video!


Third Times The Charm!
Homer
 
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lowga

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Flew my L2 certification flight yesterday at Bama Blastoff in Aliceville, AL. A 54mm minimum diameter fiberglass rocket using a 38mm adapter. J357 Blue Streak motor. Recovery was a 14" drogue chute with a 40" main. Motor ejection. Chute release was set for 200' because I was overly concerned about losing the rocket.

Flew with both an Eggtimer GPS tracker, and a Marco Polo tracker on board. Flight was uneventful with apogee at 5,470 feet. Drogue deployed immediately, and the rocket came down well. Waiting for main chute deployment--which happened right on cue--but chute fully opened at about 125 feet. Should have set it for a higher altitude--maybe 300 feet.

Rocket came down about 100 feet from the RSO table. Literally on the flight line road, struck a glancing blow to one of our club member's Toyota SUV. (OUCH! SORRY ABOUT THAT!) Rocket suffered only scrapes to the paint.

JLCR performed wonderfully again! My only advice to those new to the product is:

1.) Always ground test.

2.) Always fully charge the product before headed out for a day of flying.

I also apply liberal doses of baby powder to the chute, but we've established I'm paranoid. Quite a sight to see a grown man carrying two trackers towards a rocket that landed in the middle of the light line! HA HA.

Thanks again John for a great product.
 

ThirstyBarbarian

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I used Chute Release for my L2. Honestly, I had planned not to, and I had wanted to keep the cert attempt as simple as possible. But It turned out to be a bit windy that day, I had a slightly oversized Chute to avoid any landing damage to the rocket, and people were losing rockets by drifting into a nearby field with tall crops. So I used the Chute Release to bring the rocket down nearby. Worked great!
 

Tyler P

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I'll definitely be using a chute release on my LOC IRIS when I attempt L1 and probably L2. And probably on an Estes Argent that I found in stock somewhere.

Looks like a necessity, in my opinion. Simplest way to dual deploy.
 

Homer_S

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Flew my L2 certification flight yesterday at Bama Blastoff in Aliceville, AL. A 54mm minimum diameter fiberglass rocket using a 38mm adapter. J357 Blue Streak motor. Recovery was a 14" drogue chute with a 40" main. Motor ejection. Chute release was set for 200' because I was overly concerned about losing the rocket.

Flew with both an Eggtimer GPS tracker, and a Marco Polo tracker on board. Flight was uneventful with apogee at 5,470 feet. Drogue deployed immediately, and the rocket came down well. Waiting for main chute deployment--which happened right on cue--but chute fully opened at about 125 feet. Should have set it for a higher altitude--maybe 300 feet.

Rocket came down about 100 feet from the RSO table. Literally on the flight line road, struck a glancing blow to one of our club member's Toyota SUV. (OUCH! SORRY ABOUT THAT!) Rocket suffered only scrapes to the paint.

JLCR performed wonderfully again! My only advice to those new to the product is:

1.) Always ground test.

2.) Always fully charge the product before headed out for a day of flying.

I also apply liberal doses of baby powder to the chute, but we've established I'm paranoid. Quite a sight to see a grown man carrying two trackers towards a rocket that landed in the middle of the light line! HA HA.

Thanks again John for a great product.
... and remember: Chute Release powers off after chute activation which includes a ground test!

Homer
 

Jozef

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Used the JLCR for my L1 in a Mega Der Red Max. I have had three. Lost one in a pad fire at URRF 5.... my bad. I never fly without one in mid and high power rockets that use motor ejection. I do have a couple of 38mm mid power rockets that are challenging me to get the chute release to fit with proper tension around the chute using the small band. I just need to take some time to practice at home to get the setup correct.
 

SecondRow

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L1 last November with a Chute Release in an Estes Mammoth (2.0" diameter) on an H135W-10. With the motor, the rocket weighed 629g. Apogee at 2782 ft. I deployed the release at 300 ft.
 
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