L1 cert recovery thoughts

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Old School Doug

Unwilling participant in the idiocracy.
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I'll be attempting my L1 with a Zephyr on a H100 DMS later in the spring and I've been giving some thought to how I want to handle recovery. I've seen enough HPR launches at Bong in SE Wisconsin over the years to know that apogee deploy of the chute can result in significant walks, not to mention a fair # of rocket eating trees and water hazards. That being said I'm strongly leaning towards deploying the 36" chute around 500' with a JLCR. But I am also noodling around with the idea of deploying a smaller 15" chute at apogee to slow decent rate down a little and hopefully keep shock cord tangle from becoming a problem. The 15" would attach at the nose cone and the main on a loop farther down the shock cord. Open to thoughts, ideas, and warnings.
 
300' should more than suffice. 15" seems a tad big, a 12" chute should work. Check the speeds in OpenRocket (or I guess Rocksim) for around 70fps on drogue descent. I did my L1 not using a 4" rocket, but only 2.6" fiberglass (and not at Bong) but did use JLCR at 300' with a drogue for successful recovery.

Just need to have launched and be comfortable with the JLCR enough that its a go-to part of your launch procedures, and not just something you do for the L1 flight.

Talk to the WOOSH folks too, they have Zoom meetings (er I guess I'm a WOOSH folk since I paid the dues) and can better advise about launching and recovery at Bong.
 
I definitely can understand your concern.
My only thought would be to try and make sure your not over complicating your flight with adding extra chutes and a JLCR. If your comfortable with the added ideas then sure by all means go for it. Some people benefit from keeping it simple. I did lol

I would keep a close eye on the weather that day if the winds are calm maybe you won’t have much to worry about .
When I launched my zephyr for my L1
I reefed my parachute lines essentially shrinking the chute size a bit to help bring the rocket down a bit faster. Assuming your terrain where its landing is not rock and it’s more grass/brush style that technique can help not let your rocket drift to far. It worked for me and I still Use that technique a lot.

Good luck
 
JLCR all the way and put a heavy duty swivel inline in the shock cord and skip the extra chute. I think I had my JLCR in my MDRM at 400' for my L1 and it was windy. Very short walk SE of the pads. My Nike-X spins like mad on the way down using the JLCR and no issues having that swivel just above the body.
 
My only thought would be to try and make sure your not over complicating your flight with adding extra chutes and a JLCR. If your comfortable with the added ideas then sure by all means go for it.

As I noted, do not do this for the cert flight. Only do it if you have mid-power flights under your belt and are comfortable with the process. Low & slow, keep it simple, use a JLCR, etc, etc. are not rules, they are suggestions but at the end of the day the flyer has to do what *they* are comfortable with.
 
As I noted, do not do this for the cert flight. Only do it if you have mid-power flights under your belt and are comfortable with the process. Low & slow, keep it simple, use a JLCR, etc, etc. are not rules, they are suggestions but at the end of the day the flyer has to do what *they* are comfortable with.
That’s 100% right and as I stated also
 
I think the JLCR is a good idea, as is a swivel near the fincan. I'm not sure about the extra chute. Several of my rockets come down with the chute/JLCR acting like a drogue. The fincan and nose cone stay below the chute/JLCR combo all the way down. When that happens, the chute always pops opens quickly. I have one L1 sized rocket that falls that way and I will use as low as 100 ft. for deployment altitude.
 
I used a streamer for my initial motor ejection charge recovery event then a JLCR for the main chute at 500’ for my L1 cert flight. This was the “standard” way I flew that rocket multiple times on G motors so take this as another endorsement of the ”don’t do anything different on race day” POV.

How do I get to Carnegie Hall? Practice man, practice, practice, practice…
 
Thanks for the input all. One of my other reasons for contemplating the smaller chute on the nosecone was to try keeping the rocket in more of a vertical orientation during descent. However, I failed to take into account the effect of drag on the fins and body. So I'm putting that idea in the "probably not" category. I have been using a JLCR for a couple years now in LPR and MPR rockets so I'm super comfortable with that configuration. Adding a swivel to the shock cord is going to be a definite though..... thanks DigBaddy and Handeman. Not planning on doing the cert till April or May so my son has a chance to tag along (new daddy duties has been keeping him busy) so plenty of time to ponder.
 
I used a streamer for my initial motor ejection charge recovery event then a JLCR for the main chute at 500’ for my L1 cert flight. This was the “standard” way I flew that rocket multiple times on G motors so take this as another endorsement of the ”don’t do anything different on race day” POV.

How do I get to Carnegie Hall? Practice man, practice, practice, practice…

I've used that configuration quite often on higher flying MPRs and like it quite a bit. A silver mylar streamer helped on visibility and tended to make spotting recovery in taller late summer brush easier as well.
 
Good advice in this thread and you can go whichever way you are comfortable, but a Zephyr doesn't go very high on a small H motor. My Zephyrs usually hit about 1000-1100 feet on an H100. Barely more than that on most of the other smaller H motors. Doesn't seem like it is worth the complexity of doing anything but a simple single deploy for cert flight at that altitude. The Zephyr is a tank, though. If it burns in due to the JLCR failing to release, it may not hurt the rocket at all. You could probably shove the chute back in, throw in another motor and try again!
 
My thoughts extend the shock cord on the zephyr to at least 20’ I have watched a lot of stock Zephyr’s fail level 1 because of zippers.
 
Spend the couple extra bucks an get the ball bearing swivel, they work much better than a regular swivels. Rocksim shows deployment at 14 mph with a H100W-8.
Seems a big advantage of the JLCR would be upgrading to a 48" chute for softer landings.
Makes me wonder what the speed would be after falling say 500 feet without a chute open ?
 
I L1ed with a Zephyr H 100 W. The manual states 1996' with a 8 second delay. Very close the the Est. altitude. You can use a 30" parachute if you built it as the video shows. Its a stout rocket.
 
I'm in a similar boat, wanting to do L1 in the spring.

Question re: a streamer or drogue when used with a JLCR on the main. Seems it could be possible that the drogue could get tangled with the main, no? Is there a good method to reduce the chance of this happening? I've thought about it, but am leery about trying it.

Hans.
 
I have launch my Zephyr 5 or 6 times on RMS H 250 29mm just over 1,000'. KISS The only damage i have had was a tangled parachute, flat spin. The paint on the nosecone cracked. Get your L1 then experiment.
 
I have launch my Zephyr 5 or 6 times on RMS H 250 29mm just over 1,000'. KISS The only damage i have had was a tangled parachute, flat spin. The paint on the nosecone cracked. Get your L1 then experiment.
Agree.... Except I'd like to experiment with a streamer or drogue before the L1. That's providing there is some sort of consensus if that is a good idea. If it's likely to tangle, then I won't bother.

Hans.
 
I'll be attempting my L1 with a Zephyr on a H100 DMS later in the spring and I've been giving some thought to how I want to handle recovery. I've seen enough HPR launches at Bong in SE Wisconsin over the years to know that apogee deploy of the chute can result in significant walks, not to mention a fair # of rocket eating trees and water hazards. That being said I'm strongly leaning towards deploying the 36" chute around 500' with a JLCR. But I am also noodling around with the idea of deploying a smaller 15" chute at apogee to slow decent rate down a little and hopefully keep shock cord tangle from becoming a problem. The 15" would attach at the nose cone and the main on a loop farther down the shock cord. Open to thoughts, ideas, and warnings.
have you finished your build on the zephyr ? if not dont glue the coupler in. buy the Apogee E bay and rivet it in place. after L1 you can load it with electronics. i had to cut my Zephyr at the coupler to modify it. its now 8" longer.
 
small rocket, no drogue needed.
your main seems big
if you don't do jlcr all the time, skip it.
 
I'm in a similar boat, wanting to do L1 in the spring.

Question re: a streamer or drogue when used with a JLCR on the main. Seems it could be possible that the drogue could get tangled with the main, no? Is there a good method to reduce the chance of this happening? I've thought about it, but am leery about trying it.

Hans.
You do need to run a longer shock chords. If you put the drogue near the or on the nose cone and the main between 1/2 and 1/3rd from nose cone should be fine.

There is nothing new here. There has been enough flights with JLCR.
 
You do need to run a longer shock chords. If you put the drogue near the or on the nose cone and the main between 1/2 and 1/3rd from nose cone should be fine.

There is nothing new here. There has been enough flights with JLCR.
Thanks, appreciated. This makes sense, string them out far enough, with the drogue way out in front. My L1 candidate rocket has only one flight under it's belt, I plan to do about a half dozen at least on F and G to get comfortable with it.

Hans.
 
for level 1, make sure you do not use a parachute with very thin shroud lines, get something that the shroud lines are pretty beefy. if something happens delay wise, and you build up some speed, and then the shoot opens up, it will rip those things into pieces and you will have a rocket falling down separate from the shoot
 
for level 1, make sure you do not use a parachute with very thin shroud lines, get something that the shroud lines are pretty beefy. if something happens delay wise, and you build up some speed, and then the shoot opens up, it will rip those things into pieces and you will have a rocket falling down separate from the shoot
Happened to me on my first visit to a HPR launch (although I was there to try my hand at MPR). Newly finished Estes Executioner. Windy day, rocket weathercocked severely. When the nose cone popped off, the cheap plastic Estes chute separated from all the shroud lines. Somehow the rocket came down with no damage.

Lesson learned. I've been using better chutes ever since.

Hans.
 
The Zephyr kit is complete minus the motor retainer. i have launched the Zephyr more than 10 times and used the same chute on my super big Bertha XXL 4" upscale 4 times. the shock cord is 15' 1/2" nylon. build it, put a motor in it, launch it, then pull out your credit card, welcome to hi power.
 
Happened to me on my first visit to a HPR launch (although I was there to try my hand at MPR). Newly finished Estes Executioner. Windy day, rocket weathercocked severely. When the nose cone popped off, the cheap plastic Estes chute separated from all the shroud lines. Somehow the rocket came down with no damage.

Lesson learned. I've been using better chutes ever since.

Hans.
Most of what I have done has been scratch built. Whenever I've traveled down the Estes road with a kit or 2, I've always taken the plastic chute that comes with them and put them on the range table with a card saying "Free for the taking". Everything with a chute gets a rip-stop nylon one.
 
Look at a shock cord protector, don’t worry about a streamer as it is more that can go wrong. I would use a bigger parachute with the chute release at 400’ ft. for a rocket 5lbs or less.
 
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