TRIPLE DEPLOYMENT with Jolly Logic Chute Release

[Willy Witsel]

The Netherlands is to small for serious rocketry. That is why I use Triple Deployment with the Jolly Logic CR

With triple deployment I can safely lower my rocket at high speed without putting too much forces on the deployment of the main parachute.

Triple deployment uses two drogues. A very small one and a somewhat bigger one deployed by the CR. It is ideally suited for high flights with a limited landing area

My Drogue1@apogee is 1ft. It brings down my 4” rocket with a decsent speed of 28 m/s. My second drogue2@250 meter is 1,5ft and reduces the descent speed for a save deployment of the main@150 meter

Video

 

[Steve Shannon]

That’s clever. What about using just the larger drogue, but using the chute release to keep it reefed?

 

[Zeta]

That’s clever. What about using just the larger drogue, but using the chute release to keep it reefed?

When using a JLCR I make sure the rubber binder wraps the chute/drogue onto the shock cord. This prevents it from spinning and thus twisting the lines up and reefing the chute. My thought would be if a JLCR was used to reef a chute that it would spin and when the release opens the lines on the chute would be twisted and the chute would not fully open. Maybe there is a technique here I am not aware of. ?

 

[SolarYellow]

See comment below. I'm an idiot who doesn't take time to watch YT videos.

 

[Steve Shannon]

Cool idea. I remember lots of open fields, I guess the plots are small or the larger farmers aren't interested in helping? Even here in Texas, I have to drive an hour and a half to an HPR launch.

Just a note about English sequencing abbreviations. I hope to be helpful rather than a pedantic grammar Nazi.

My Drogue1@apogee is 1st. It brings down my 4” rocket with a descent speed of 28 m/s. My second drogue2@250 meter is 1,5st and reduces the descent speed for a save deployment of the main@150 meter.

To us non-metric-system-using American, as well as "bilingual" technical people, "ft" is an abbreviation for "foot" or "feet." It's the unit of distance that most of our brains work in, instead of meters. The common abbreviation for "first" using the numeral is "1st." Similarly,

1st
2nd
3rd
4th
5th
...nth...
20th
21st
22nd
23rd
and so on...repeating at each increment of ten.

I think he really did mean that the first drogue was one foot in diameter and the second was one and a half foot.

 

[thzero]

I like it!

 

[Willy Witsel]

That’s clever. What about using just the larger drogue, but using the chute release to keep it reefed?

I also considered reefing the drogue but then you run the risk that the patachute gets tangled

 

[Willy Witsel]

See comment below. I'm an idiot who doesn't take time to watch YT videos.

You did not miss much Solar

 

[Willy Witsel]

I think he really did mean that the first drogue was one foot in diameter and the second was one and a half foot.

Correct Steve

 

[Willy Witsel]

I like it!

Thanks If I have a video I will post it here

 

[Willy Witsel]

The Netherlands is a very small country. Just a dot on your map. Therefor we are only allowed to fly rockets up to 1800 meter.

I used a Madcow Super DX3 and changed that by making it stronger



But it also made the DX3 heavier. He now weighs 3,6 kg. And I need a 4,5ft main-chute@150m to land it safely.

If I want to reach an altitude of 1500 m, a 1 ft drogue@apogee takes me with a speed of 28 - 30 m/s to the 150 m where my main opens.

But the forces during main deployment are dangerously high. But with a bigger drogue I might land in Germany.

That's why I want to use Triple Deployment with two drogues, a small one and a slightly larger one. The small drogue@apogee with black powder deployment and the second larger drogue@240m with the JLCR.

The second drogue reduces the descent speed to approximately to 17 - 20 m/s. Safe enough for the deployment of the main@150m

PRO’S AND CON’S TRIPLE DEPLOYMENT

PRO: can be used in high flight and small landing area’s

CON: More complex than standard dual deployment. More could go wrong

 

[Neutronium95]

I feel like this is just adding complexity for no real benefit. I regularly use a drogue descent rate of 22-30 m/s on my rockets, and have never had an issue with excessive shock loads during main deployment.

The one thing to look out for is to make sure that the main is deployed at a high enough altitude that it will have time to fully open before landing.

 

[waltr]

Another thing to do is ensure the cord for the Main chute has a way to absorb energy as it extends.
Two common methods are:
Do a few taped bundles that pull apart.
Braid the cord.

I have had good success with both methods. Even had a very lond delay that allowed a 1.2 kg rock coming down from 600 ft (180m) ballast then deploy at 100 feet (30m) from ground. Braided 3/8in nylon absorb energy and NO damage to chute, cords or even no tube zipper.

 

[jahall4]

I've been using a JLCR since 2019 to deploy a 2nd (redundant) main.