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

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I had my L3 before I considered getting a JLCR. I've gotten two so far (first was lost when the motor eject fired at motor burnout). They work great!

The only problem with the JLCR is that they are very, very, very expensive! It's not the cost of the JLCR, it's the cost of the bigger motors you can now fly in conditions you wouldn't have done before!

With the JLCR, instead of a $14 G64W, I'm flying the $20 H128W or $24 H180W. This thing is going to make me go broke! :cool:
 
I know a guy who just certified NAR L1 using a JLCR. I'll see if I can get him to post here about it.
 
I did my TRA L2 cert today with a Jolly Logic Chute Release and an Altimeter Three along with my own DIY flight computer/telemetry/GPS tracker. I used my PML Quicksilver with an Aerotech J270W-14. The rocket weighs 43 oz without the motor and 65.5oz with it (4.1lbs). Over 7500 feet and about 0.97 Mach. It was a gorgeous flight!

Here's the info from the Altimeter Three:
Quicksilver (2.1" diameter)
Max altitude 7533 ft
Date 4/15/2017 9:57 AM
Mode Rocket
Duration 2 mins 26 secs
Notes J270W-14
Thrust time 2.05 secs
Max speed 742 mph
Peak accel 23.14 Gs
Avg accel 16.49 Gs
Ejection delay 14.35 secs
Coast-Apogee 16.25 secs
Apogee-Eject -1.90 secs
Ejection altitude 7446 ft
Initial descent 63 fps
Landing speed 29 fps

FlightGraph.png

I attached the data file. Here are a few photos of the launch:

IMG_8713-crop.jpg IMG_8715-crop-fix.jpg

Here's a video of the flight:
[video=youtube;3pLu6K_kUbA]https://www.youtube.com/watch?v=3pLu6K_kUbA[/video]
 

Attachments

  • FlightReport.xlsx
    316.6 KB · Views: 60
TRA L2 Cert 6/23/17
4" Diameter 50" length Binder Design Excel.
38 mm Aerotech J270 to just over 4600 ft. JL Chute release at 800ft.

Thanks John!
 
I did my Level 1 cert on an Estes Argent. Stock build with 5 minute epoxy. Successful flight with H115DM-12. ~2200ft and my Jolly Logic Chute Release opened perfectly at 300 feet. Thanks John for the tech support.

FB_IMG_1488732182971.jpg
 
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I did my Level 1 cert on an Estes Argent. Stock build with 5 minute epoxy. Successful flight with H115DM-12. ~2200ft and my Jolly Logic Chute Release opened perfectly at 300 feet. Thanks John for the tech support. That's the picture next to my name. still learning how to upload an image.

Nicely done. Congrats, Eric!
 
L1 built on the flight line at Airfest. mostly stock Mammoth, H97J-M(~10s), ~3k simmed alt, JLCR @300

49e0d68ce263d0730f176f00c7b1697b.jpg
 
Used one on a 44k N flight and will be using one next week at ARLISS on an O motor going to about the same altitude. Neat little pieces of hardware.
 
Used one on a 44k N flight and will be using one next week at ARLISS on an O motor going to about the same altitude. Neat little pieces of hardware.

Now that's inspirational! I'm hoping to use it for my 54 mm MD project, if I ever get around to building it.
 
I did my L2 last month using two Chute Releases. I linked them together to ensure redundancy. The battery on my Altimeter 3 died before the launch, so I don't have data, but it was a great flight to ~2500 ft. I set the Chute Releases to 300 ft. because I wanted to make sure it landed on the field, but in retrospect, I should have set it to 500 ft. I nearly had a heart attack before it opened.

ImageUploadedByRocketry Forum1503284676.617662.jpg
[YOUTUBE]vgXmhsdGRu8[/YOUTUBE]
 
I did my L2 last month using two Chute Releases. I linked them together to ensure redundancy. The battery on my Altimeter 3 died before the launch, so I don't have data, but it was a great flight to ~2500 ft. I set the Chute Releases to 300 ft. because I wanted to make sure it landed on the field, but in retrospect, I should have set it to 500 ft. I nearly had a heart attack before it opened.

View attachment 327416
[YOUTUBE]vgXmhsdGRu8[/YOUTUBE]

Next time split the difference and go for 400' and a mild heart murmur.
 
Ummmm, Folks are really taking a chance with these really low level deployments. I've seen a few smack the ground and I've had a stiff chute protector hang the chute deployment twice. Once with a cardboard rocket (destroyed) and once with a glass rocket that survived. I've since arranged the chute protectors on the harness so they get pulled free once the CR releases the band. I fly at a large venue and won't go lower than 700'. With a GPS tracker I'll release higher so
I can get a drift trend on a map. Like I said, I have a site with room to do that. There's no reason to do heart stopping low level releases at large launch sites if
one wants to walk away with a reusable rocket! You lucked out on that cert and lesson learned I 'spose. Kurt
 
Used on my L2 certification flight in July. Madcow Frenzy on an Aerotech DMS J270-10. Apogee at 3,012 ft, chute release at 400 ft. Perfect flight - just took a while to find in the corn.

Chris
 
Used on my L2 certification flight in July. Madcow Frenzy on an Aerotech DMS J270-10. Apogee at 3,012 ft, chute release at 400 ft. Perfect flight - just took a while to find in the corn.

Chris

Stick something like this on the harness if you got the room and I guarantee you'll hear the thing coming in! https://www.safetybasement.com/Personal-Attack-Alarm-with-Flashlight-140dB-p/sb-p140.htm
There's several 140dB ones out there and easy enough to arrange it on the harness so the pull-pin is yanked out at apogee. Kurt
 
Ummmm, Folks are really taking a chance with these really low level deployments. I've seen a few smack the ground and I've had a stiff chute protector hang the chute deployment twice. Once with a cardboard rocket (destroyed) and once with a glass rocket that survived. I've since arranged the chute protectors on the harness so they get pulled free once the CR releases the band. I fly at a large venue and won't go lower than 700'. With a GPS tracker I'll release higher so
I can get a drift trend on a map. Like I said, I have a site with room to do that. There's no reason to do heart stopping low level releases at large launch sites if
one wants to walk away with a reusable rocket! You lucked out on that cert and lesson learned I 'spose. Kurt
My rocket weighed a pound and change with over 400in^2 of surface area and I had sent it's twin brother up several times at 1-2k feet in a highly similar configuration. No nomex, only barf. That's not luck, it's practice :)

I agree you should rather think about how many -seconds- above ground you're popping the CR.
 
Recently got my Tripoli L2 using a chute release.

Flying a Wildman Punisher with an Aerotech J450DM. Flight simmed to 7,300' at approximately 750 MPH.

19059086_10155365906659687_2390009758594636547_n.jpg


[video=youtube;xdjnimCE0xw]https://www.youtube.com/watch?v=xdjnimCE0xw[/video]
 
If I go for L2 this year I will be using a Chute Release. The rocket I am currently building that can handle J motors, can't be set up for standard dual deploy without modifications, and I don't want to do that. Every L1 flight I have ever done has been dual deploy so I know how to do that. The question is do I want to shove a J motor in my newest rocket? Looking to join the mile high club... the rocket kind! Hmmm..........
 
Made a successful level 2 attempt on September 16, 2017 with an AMW Red FiberMAX using a CTI J335. The rocket weights every bit of five pounds dry. Recovery was with a 36-inch Sky-Angle and a 12-inch X-drogue (sorry I don’t remember who made it) with the JLCR set to 400-feet. Weather was partly cloudy, 10-15MPH winds out of the South and about 90-degrees F. This was my second attempt. Text book flight. The JLA2 reports 2979 feet altitude.

The first attempt was made last month with the same rocket and a CTI J185 with no drogue (the fatal error.) That long motor made the airframe stable and so it plummeted from apogee dragging the nose and recovery system behind it. Should have caught that when I getting it ready to launch; felt like a rooky. The release was set at 500-feet but by the time it cycled it had already taken a core sample. Damage to the rocket was light and limited to the coupler.

And John, the HP-41 on your web site home page warms an old man’s heart.
 
If I go for L2 this year I will be using a Chute Release. The rocket I am currently building that can handle J motors, can't be set up for standard dual deploy without modifications, and I don't want to do that. Every L1 flight I have ever done has been dual deploy so I know how to do that. The question is do I want to shove a J motor in my newest rocket? Looking to join the mile high club... the rocket kind! Hmmm..........

Might need a tracker or wait for zero wind. Kurt
 
I used a JL chute release on my PML Quicksilver with a J270 for my Level 2 cert. Went to 7100 ft, motor deploy at apogee, chute release at 600ft, and it landed about 200 yards from the pad. The harness got a little tangled on the way down but otherwise everything worked fine. I'm thinking I'll use a streamer or small drogue with the chute release from now on just to help keep the harness stretched out and avoid tangles.
 
Made a successful level 2 attempt on September 16, 2017 with an AMW Red FiberMAX using a CTI J335. The rocket weights every bit of five pounds dry. Recovery was with a 36-inch Sky-Angle and a 12-inch X-drogue (sorry I don’t remember who made it) with the JLCR set to 400-feet. Weather was partly cloudy, 10-15MPH winds out of the South and about 90-degrees F. This was my second attempt. Text book flight. The JLA2 reports 2979 feet altitude.

The first attempt was made last month with the same rocket and a CTI J185 with no drogue (the fatal error.) That long motor made the airframe stable and so it plummeted from apogee dragging the nose and recovery system behind it. Should have caught that when I getting it ready to launch; felt like a rooky. The release was set at 500-feet but by the time it cycled it had already taken a core sample. Damage to the rocket was light and limited to the coupler.

And John, the HP-41 on your web site home page warms an old man’s heart.

I've taken to adding a drogue chute on my larger rockets that use a chute release. A little added insurance to keep the nose at or above the booster section.
 
I've taken to adding a drogue chute on my larger rockets that use a chute release. A little added insurance to keep the nose at or above the booster section.

Yes, it's my opinion that I need at least a streamer for pretty much everything; a drogue is preferred, even if it's a small one.

I spent most of the last launch flying the same unglamorous rocket over and over on G impulse motors until I had a technique that would reliably open a chute quickly after the release. My success rate with the release went from less than 50% to better than 90% with a drogue. One of the advantages of using a drogue is that the main opens rapidly rather than the hang-fire-flapping we so often see with a simple tumble, this means you can set the thing to release lower on windy days and use a bigger chute than you might otherwise. The other thing that had a big affect was to sandwich the shock cord between the chute and the release. Don't know why but that seemed to make a big difference.
 
JL recommends folding shroud lines inside the chute, are people doing this? I have and have a 100% success rate.
 
JL recommends folding shroud lines inside the chute, are people doing this? I have and have a 100% success rate.

That's how I do it. My only "failures" with the JLCR are when the bundle gets stuck in the tube. As long as the chute gets out, I too have a 100% success rate.
 
If you used Chute Release in your cert flight, could you please holler out your details?
Rocket (with diameter and weight, if you know them)
Motor​
Altitude (if you know it)​
PML Bumble Bee (3.9" diameter, 1,555g without motor)
Flying on: AT H100W-10A 38mm DMS
Flew to: 1447' on a windy day (~10mph steady, gusts to ~15mph), CR released successfully at 300'...

L1

Gory details - chute got tangled up upon CR release, and never fully inflated.
Rocket came down on 48" chute acting as a streamer, landed ~20" feet from the launch pad. One slightly cracked fin fillet, otherwise, no damage, and good to fly again. Which counts as a successful L1 flight.

CR did release and chute did successfully inflate at 300' during a preceding test flight on a G-motor.
CR worked as advertised every time, flying this an other rockets. I chalk up L1 flight entanglement on chute packing user error.

a
 
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