L1 chute release attachment

[Gary Liming]

I am rigging my L1 attempt using a JL Chute release. The nose cone is one of those with the plastic loop, which seems kind of weak to me, so I am hesitant to attach the shock cord, the parachute, and the JLCR to it. I am thinking of using a swivel on the chute and tie everything to that, using a kevlar leader of maybe 8 inches or so from the swivel to the nose cone. Will the nosecone-on-a-leader increase the chances for a tangle with the JLCR? What's the right way?

 

[crossfire]

If your not flying to high maybe dont use JLCR for your cert flight. Just keep it simple as you can.

 

[schneijt]

Many people drill two small holes into the nose cone base to run the shock cord through on a nose cone with a molded plastic loop like that. It’s much less likely to fail than using the thin plastic loop that’s already there.

I would recommend attaching the parachute approximately 2/3 of the way up the shock cord from the body tube, and I like to use the JLCR tethered to either a shroud line if it is a reinforced, heavy duty parachute, or to a loop in the shock cord. Having said all that, I agree that using the Chute Release may not be the best choice unless you’ve used it successfully several times already. They are incredible little devices, but they have a bit of a learning curve and you need to experiment with it for your own uses to have the best reliability with it. It is simply one more thing that could possibly go wrong on a L1 cert flight. If you do opt to use it, make sure you do several ground tests to ensure it will release properly and that you minimize any chances of anything tangling in your recovery setup

 

[dr wogz]

And many will tie a loop in the shock cord about a foot down from the NC.. That way, if the NC does separate, the chute & all is still attached to eh rocket (albeit an object is coming in hot!) it also allows more room to attach all this stuff..

Ditto on the JLCR learning curve. A few have lost one within their first few fights.. (forgetting to tether it being the #1 reason)

 

[teepot]

I would also suggest to keep your L1 attempt simple. I have 2 chute releases now and am going to do my L2 without one. One less thing to go wrong.

 

[crossfire]

No one has 100% success with any DD. So why not just eliminate a failure point for a cert flight

 

[Nytrunner]

I'm the usual opponent of the KISS cert flights.

A cert flight is a great opportunity to learn something since it's inspected more closely by an experienced rocketeer who can point things out and advise through the process.

If you do fail? Big whoop, you get to fly another rocket!

 

[gna]

I used a chute release on my L1. I flew my Estes Leviathan on Fs and Gs with the chute release before my cert flight so I knew what to expect.

I didn't want to attach everything to the nosecone loop, so I put about an 8" kevlar lead to the nosecone. I had a quick link at the end of the shock cord, so the chute release, parachute swivel, and nosecone lead all attached there. Seemed to work fine.

 

[David Schwantz]

I use a loop just long enough to get the JLCR back through. Shorter it is, the less to tangle. I attach it to the shock cord, not a shroud line, as what happens if the shroud line breaks? I also flew my L1 with no electronic stuff. KISS. If you do choose to use a JLCR, remember to turn it on Good luck with your flight.

 

[Gary Liming]

I have played with the JLCR quite a bit and am comfortable with its programming and operation. I also like check lists. I have "turn on the JLCR" on it, as well as "make sure JLCR is tethered" and I will pack it as shown on the JL video. Anything else I am missing?

 

[dr wogz]

have you had any launches with the JLCR?

(it's one thing to play with it, in your basement, in front of the 'tube, or wrapping it around your fingers & letting it snap off.. It's an entirely different thing when it's flapping about and it gets snagged on a partially opened chute..)

 

[Joshua F Thomas]

At our club (CATO), a member flew his L1 cert on the LOC 4" Goblin. The flight was beautiful and the chute deployed nicely, I'm guessing around 1000 ft. The rocket drifted..... right over the field and into a nearby swampy area.

The owner was never able to recover the rocket and that L1 flight was a failure, plus he lost the rocket.

I'm definitely planning on using a JLCR for my L1, after testing it on other non-certification flights to work out any bugs.

 

[Gary Liming]

It's an entirely different thing when it's flapping about and it gets snagged on a partially opened chute..)

I think I understand the advice of making a cert flight as risk averse as possible, but what the first post asked was if a JLCR is to be used, is there any experience out there that can tell me how to best rig it to decrease the chances of a failure?

OTOH, along the lines of Nytrunner, why should a cert flight be different than any other in terms of risk? I sure see other people using GPS, cameras, loggers, JLCRs, etc- even DD on Lvl1 cert flights. I don't want to lose my rocket on any flight, but eventually you want to do more than just a top and pop.
Given that eventually one does take more risks to expand the tech envelope, why does it matter if it happens on a cert flight or not? In principle, should we look down on a fellow rocketeer if it takes 2,3, or more tries for a cert? I don't think so - no matter the failure mode, as long as its a learning experience, it's all good.

 

[Saint_Tiki]

I'm the usual opponent of the KISS cert flights.
A cert flight is a great opportunity to learn something since it's inspected more closely by an experienced rocketeer who can point things out and advise through the process.
If you do fail? Big whoop, you get to fly another rocket!

I'm of this opinion as well. I'm a newb, don't have an L1 yet, so take that with a grain of whatever.

But what is the point of a certification process if you are gonna play this pretend game where you launch the lowest risk, highest chance of success combination to get your cert, to then immediately go on to flying what you're really planning to fly in the first place with no practice and less oversight. Do you want your airline pilot to be tested like that? Only do their checkride in perfectly calm winds on a sunny day with a perfect airplane?

I think you should cert like you plan to fly. If you fail, you weren't ready. Guess what, do it again in a month but better.

 

[Saint_Tiki]

I have played with the JLCR quite a bit and am comfortable with its programming and operation. I also like check lists. I have "turn on the JLCR" on it, as well as "make sure JLCR is tethered" and I will pack it as shown on the JL video. Anything else I am missing?

I'd go launch it a few times on something mid-power. That's what I'm doing. You'll find that tube diameter, packing technique, etc, all play a role in success rate. You'll be more confident if you launch like that several times as well before your heaviest and most expensive rocket is on the line.

I think best chance of having it work correctly is if has enough drag to be a quasi-drogue and be the highest thing in the shock cord chain. That way, there's nothing above it for the chute to crash into. I'd pack the chute as sort of a tube so it had a bit of surface area above it to make it more draggy than the NC or the fin can.

I would also recommend not leaving your chute packed in overnight. I had a failure the other day where the "memory" of the nylon prevented it from opening. Also had a failure where the setup was too tight in the tube and only partially ejected. This is all on mid-power in a relatively low diameter (1.75") rocket. I switched to a more compact chute that folds up tighter and comes out easier on ejection and that's been working well. Landed 6 feet from the pad 2 days ago after getting to 1000 feet.

 

[Joshua F Thomas]

But what is the point of a certification process

Many people have asked this. The certification process for L1 only requires you launch and successfully recover a rocket you have built yourself, on an H or I class motor. That's it. You might have a point about certification should test or mean more, but that rapidly becomes a can of worms about what should or should not be tested.

Also, it's hard to "cert like you plan to fly" if your models or plans change over time. Should a new rocket mean a new cert? D.D. mean a new cert? New electronics? The L1 authorizes you to buy H and I motors, that's it.

 

[Gary Liming]

Only do their checkride in perfectly calm winds on a sunny day with a perfect airplane?

I had to laugh at that one - I took my private checkride on a windy day that had some of the worst turbulence I ever experienced. It worked in my favor, though, as the examiner was pretty anxious to get it over with!

 

[Joshua F Thomas]

It's kind of weird to compare PPL certification - which requires ~40 hours of logged flight time and a written test - with a hobby rocket certification. They're not even in the same class of training or risk. It's like comparing an endorsement on your driver's license for motorcycles with getting a class A CDL with all the endorsements.

 

[jrap330]

I think I understand the advice of making a cert flight as risk averse as possible, but what the first post asked was if a JLCR is to be used, is there any experience out there that can tell me how to best rig it to decrease the chances of a failure?

OTOH, along the lines of Nytrunner, why should a cert flight be different than any other in terms of risk? I sure see other people using GPS, cameras, loggers, JLCRs, etc- even DD on Lvl1 cert flights. I don't want to lose my rocket on any flight, but eventually you want to do more than just a top and pop.
Given that eventually one does take more risks to expand the tech envelope, why does it matter if it happens on a cert flight or not? In principle, should we look down on a fellow rocketeer if it takes 2,3, or more tries for a cert? I don't think so - no matter the failure mode, as long as its a learning experience, it's all good.

I see what Josh posted ,but I would blame the Rocketeer for launching a rocket to 1000 feet. He should have used a motor that gave the lowest altitude while achieving a cert. You don't drive a Maserati for your road test, or a Big , Honking Chevy Suburban. You want to pass and experiment later on. But go ahead and tried it on some flights beforehand. Maybe some Mod Rockets.

 

[Saint_Tiki]

It's kind of weird to compare PPL certification - which requires ~40 hours of logged flight time and a written test - with a hobby rocket certification. They're not even in the same class of training or risk. It's like comparing an endorsement on your driver's license for motorcycles with getting a class A CDL with all the endorsements.

True, they are completely incomparable. One requires training time and one requires zero. And further, one allows flight over people, one allows flight in deserted field into waivered airspace.

The certification process seems significantly underdeveloped if safety and accountability are the actual goals. You can do a lot of damage with an L1 motor in a rocket that doesn't separate or where the fins fall off in flight, or where your stability calc was wrong. I guess that's what RSO's are for, a final sanity check to save everyone's bacon. Side note, I'd be curious how often rockets get rejected at the table?

Still, there is a very large space between the minimum requirements demonstrated to buy an L1 motor and the upper limit of what you can do on L1 with no training or certification along the way. That leaves people free to experiment and do cool things, which is awesome, but is directly in opposition to safety checks and balances which is the purpose of a certification program. While we are talking about aviation, PPL, single engine, multi engine, tail wheel, type ratings, commercial, instructor, ATP etc are all separate endorsements or ratings that require additional training and demonstrated proficiency. Should you have to prove you are DD capable with your rocket before allowing it unsupervised? I don't know. I think the dollar cost of failure might be enough incentive...

As a new guy to this hobby, I see the certification process mostly as something lobbyists to federal organizations can point to and say, "See, look at our processes, we are safe and accountable. We've got membership, rules, and different levels. Please don't restrict sales, transportation and shipping of our propellant and allow us to easily acquire airspace waivers."

And that's totally fine. Freedom is a great thing if handled responsibly. But I don't think people should be discouraged from going above the bare minimums on their L1 cert. That just makes the goal of L1 cert to "get in the door first" then experiment later when no one is watching. Seems counter to good safety culture.

 

[Saint_Tiki]

I had to laugh at that one - I took my private checkride on a windy day that had some of the worst turbulence I ever experienced. It worked in my favor, though, as the examiner was pretty anxious to get it over with!

Haha, awesome. I had the #1 engine catastrophically fail at FL390 on one of my checkrides... Passed though!

 

[dr wogz]

I think I understand the advice of making a cert flight as risk averse as possible, but what the first post asked was if a JLCR is to be used, is there any experience out there that can tell me how to best rig it to decrease the chances of a failure?

OTOH, along the lines of Nytrunner, why should a cert flight be different than any other in terms of risk? I sure see other people using GPS, cameras, loggers, JLCRs, etc- even DD on Lvl1 cert flights. I don't want to lose my rocket on any flight, but eventually you want to do more than just a top and pop.
Given that eventually one does take more risks to expand the tech envelope, why does it matter if it happens on a cert flight or not? In principle, should we look down on a fellow rocketeer if it takes 2,3, or more tries for a cert? I don't think so - no matter the failure mode, as long as its a learning experience, it's all good.

Perfectly well said. I do say to the few cert flights I've witnessed: "don't be nervous. it's a flight like any other. just with a bit more smoke, and a bit more power, and a lot of eyes on it! Every flight is a test."

We see quite a few who are nervous for their cert flight. Some make it a big deal. If you are confident in your abilities, you'll do fine. We also see people wanting to do a cert flight with a freshly built min diameter with DD & trackers, none of which have flown before, and the flyer has barely a year of rocketry under their belt.. It's a flight, one that you are being judged on by your peers. One that should be easy to pass. But we've seen failures, and some from just plain stupidity or it being rushed. Once you've got it [the certification], you are free to do what you like, within the safety margins of course! And, asnother thing I say: "It's not a race"

As for the JLCR, I feel it takes a bit of practice & and a bit of "is this right?" as you pack it up to get it right. Something that I feel is more learned and 'felt' rather than explained in a paragraph or two.. And something that is best done with an experienced person beside you who can watch & see what you do.. Heck, you might even teach them something!

As mentioned, we've seen people rush things, and get things expecting 100% success right out of the box, with little to no effort on their part to learn & understand... And they wonder why they fail..

 

[Joshua F Thomas]

I see what Josh posted ,but I would blame the Rocketeer for launching a rocket to 1000 feet. He should have used a motor that gave the lowest altitude while achieving a cert. You don't drive a Maserati for your road test, or a Big , Honking Chevy Suburban. You want to pass and experiment later on. But go ahead and tried it on some flights beforehand. Maybe some Mod Rockets.

You pretty much can’t get less than 1000 feet on any H motor on a 4” Goblin.

I over-engineered mine with more mass in the nose cone, so it will go a little lower, but I’m still thinking around 800 feet.

It really would be nice to have a bigger field, but I live in Connecticut. Trees, trees everywhere.

 

[Nytrunner]

Although i go against the KISS grain, thats a philosophical standpoint, and I'm not lobbying for increases stricture in the cert process.

I think the current levels system is a vast improvement over "Fly an H and now you're qualified to fly everything up to an O" system of the past. There's structure but also freedom allowing the KISS crowd and the learning project crowd to progress in their own chosen streams.

As far as losing a 1000ft flight, I think thats less a high power deal and more a "fly the field" skill. Amusingly enough, the day I got my L1, I also lost my Estes Magician on an E9 when it drifted into "the tick woods"

 

[Joshua F Thomas]

> As far as losing a 1000ft flight, I think thats less a high power deal and more a "fly the field" skill.

You mean by, say, using a device that would deploy the chute at a lower altitude and prevent excess drift?

 

[Nytrunner]

You mean by, say, using a device that would deploy the chute at a lower altitude and prevent excess drift?

That's one option, if you have one available and suitable for your rocket.

If not, the harder skill is being able to say "you know what, today is not the day to fly this configuration".

*or asking for rail angle and direction advice on the field to put the flight path in a better position for recovery

 

[pbahorich]

I think I understand the advice of making a cert flight as risk averse as possible, but what the first post asked was if a JLCR is to be used, is there any experience out there that can tell me how to best rig it to decrease the chances of a failure?

There was a discussion a while back about this and I summarized and wrote up the best of it (posts from Cameron Anderson) in the attachment. I had several failures prior, but since I have followed it have had a string of only successes.

 

[Gary Liming]

Thanks, pbahorich!

 

[teepot]

I've been rolling mine up. I'll have to try the accordion fold. Seems the chute would open faster that way.

 

[XrayLizard]

I posted, but then thought I should not lol. Edited!! Lol