good dual deployment with gps

I'm looking to go to the entry all the way to level 3 and I'm looking at a lot of alts a lot with dual deployment some not but I'm hearing I need gps tracking in level 3 and I'm wondering is it better to get 2 of the same or 1 with gps or a side unit all together

Who said you need GPS tracking for L3?

GPS tracking is useful for high-flying rockets, but you don't need to fly high for L3, just an M motor. So, you can fly a heavy rocket on a baby M and keep it low. In fact, a lot of people recommend keeping the flight simple to get the cert out of the way.

For example, I used a full "M" (AT M1939), but otherwise flew a very conventional 3FNC for my cert. It went only 13,000' so was easily recovered without a GPS.

That said, the TeleMetrum is a very nice unit with dual deployment and GPS tracking. The nice thing about an integrated package is that the telemetry includes the flight computer state, not just the position.

There is no requirement for GPS. You need to use electronic deployment for L3 rockets. This is because L3 rockets do not have ejection charges.


NAR L3 Requirements: https://www.nar.org/wp-content/uploads/2014/08/L3certreq.pdf

TRA L3 Requirements: https://www.tripoli.org/Certificati...evel3CertificationInfo/tabid/244/Default.aspx

Bob

ok that's good to know ill more than likely go with the TeleMetrum just do to if I do a high flier later I can use it on that too

JohnCoker said:

GPS tracking is useful for high-flying rockets, but you don't need to fly high for L3, just an M motor. So, you can fly a heavy rocket on a baby M and keep it low. In fact, a lot of people recommend keeping the flight simple to get the cert out of the way.

For example, I used a full "M" (AT M1939), but otherwise flew a very conventional 3FNC for my cert. It went only 13,000' so was easily recovered without a GPS.

That said, the TeleMetrum is a very nice unit with dual deployment and GPS tracking. The nice thing about an integrated package is that the telemetry includes the flight computer state, not just the position.

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Ahhhhh, depends upon where one is. Out west in the wide open spaces I'm told folks find they can fly high and find 'em pretty easily. In the crowded midwest with the varied terrain, a tracker of some kind is helpful. You only fly at major launches and there is a chance if you can't find your rocket, someone else will turn it into the LCO table. Taking the time to learn how to RDF track is good insurance or take the lazy man's way out and use a GPS tracker. I've put small rockets 5 to 8k feet and would have lost them
every time without the GPS tracker. Both apogee and main events occurred but the main chute wasn't seen at .5 to 1.5 miles away. Yeah with a larger rocket that distance of being able to be seen goes up.

The other thing you will need to keep in mind is some TAPS will insist that they see the rocket decending under the main chute or they won't sign off on it. So that is food for thought if going for screaming altitude on an L3 certification. Might want to use a higher main deployment like 1000 or 1200 feet so the main is more likely to be seen at altitude. I've done it with small rockets with J's. Nothing seen but it's obvious from the descent data from the GPS and the altimeter that all the events occurred nominally. At least get that issue cleared with a potential witness. If you expect a possibility of a "sight unseen" cert attempt that
recovers out of sight but normally, will they accept a review of your data to support that the apogee and main events were nominal? That can be easily seen from an altimeter download. Ummmm, if you're going to cert in this manner, you'd best use at least one altimeter that records the altitude over time and not just use two Adept 22's!:wink: It would be a cry'in :cry: shame to have a successful flight labelled a DNF due to a "technicality". Kurt

Dual deployment and GPS tracking are two different things. Although it is possible to get both in the same piece of electronics, they are two completely different functions.

With an L3 cert, you will need redundant dual deployment electronics. Any type of tracking RDF or GPS is not required.

If you do decide to get a single altimeter with GPS, just remember, you need a second altimeter as either the primary or backup for the L3 cert attempt.

Slow down, get level 1 and 2, then plan your L3. The things you learn during that process will help you to plan the L3. That's why there's an L1 and L2. You will change your mind on every subject in rocketry at least ten times between now and then.

Enjoy the ride...

I do a lot of research before making 1 move do to this after all the info I don't change my mind much ive been laying out a plan for all levels in level 1 the rocket is done to get all the way to lvl 2 other than the motor and for the lvl 3 my 2nd alt a new canister system for the new size and the motor

I wasn't saying planning was bad. Just that experience will guide further planning, and that experience isn't totally able to just be researched.

It's possible to plan an L3 without any experience. But not the best path, and may lead to issues that could be avoided. Depending on what organization you're in you may not even be able to submit plans until you're L2. I'd get in contact with some TAPs if you're in TRA, and their equivalent if NAR. They'll have the best advice, as they'll be the ones signing off on the project.

hawlk2004 said:

I do a lot of research before making 1 move do to this after all the info I don't change my mind much ive been laying out a plan for all levels in level 1 the rocket is done to get all the way to lvl 2 other than the motor and for the lvl 3 my 2nd alt a new canister system for the new size and the motor

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Same here Hawk, I do my research first. Ideally you can build and fly the same rocket for L1 and L2, L3 though requires an approval and documentation and oversight process where its better (IMO) to build a rocket just for it. Go ahead and get a altimeter that works for dual deploy or even one with GPS/tracking, you can still use them in L1/L2 rockets even if they are just along for the ride and data collection (thats what I did in my L1 Crayon). My L2 flight will be DD but using a different rocket (the one that was originally intended for my L1 and L2 flights). I use a MissleWorks RRC3 and really like the altimeter, when I go for L3 I will probably pick up a Stratologger CF for my secondary/redundant (mainly because I want an even smaller altimeter for small minimum diameter projects) and its price. No tracking yet in either of these rockets, but it will eventually happen.

Depending on your experience with building and flying low power rockets, a kit is usually recommended for Certifications, that being said if you have built and flown an number of Low and Mid power rockets and scratch built a few of them then scratch building a Certification rocket is not out of reach.

My L1 was the Pink Crayon (it was supposed to be the Red one which got totaled on its maiden flight by too long a motor delay) which is a scratch build.


My L2 is a clone of the Madcow FrenzyXL 3" with the fincan modded to be zipperless. So basically its scratch built. Only this rocket actually saved me any money over a kit, and the only reason is that the real 3" Frenzy XL is all Fiberglass and mine is FG wrapped Loc tube airframe.

nice rockets but I had another thread on here for the alt cal was looking for my L1 was about 900 feet the rocket is a kit but it said to use a J to M using the 54mm adapter I put an I445 on it and then for L2 all I got to buy is the motor which will be a j 760 both will use the 54 mm 3 grain casing but on the L3 im going with M 2020 right now im looking with that I can get to a L3 under $2,000 or with a gps sepret looking at just over $2,000. the L1 like I said estimated at 900 feet the L2 the sim don't like the motor keeps saying the propellant is more than the motor but my L3 it said 10,000' but it dose not do the trans and super sonic will. but looking to do dual deployment all the way

Aerotech M1350. 250 bucks, no hardware. https://www.siriusrocketry.biz/isho...50w-p-75mm-dms-hazmat-special-order-1584.html

What kit did you pick up for L1 and L2?

https://www.dropbox.com/s/cjo7wzrxk5irqqr/rocket.ods?dl=0
this is my list its in open office 4.1.1 or better

ok just looked at the m 1350 nice might use that not sure yet but it would make it cheap for L3

Hello hawlk2004,

Welcome to the forum.

Maybe I'm reading your posts incorrectly... but it looks like you intend to use the same rocket to certify L1, L2, and L3.

I'm not sure that is a very good idea, and under the NAR rules, I'm not sure that's even allowed.

Before you go too far with this, you may wish to read over the NAR cert requirements, and have a talk with your NAR L3CC.

From reading the NAR L3 Certification process the L3 build cannot begin (paperwork cannot be started until the L2 is complete) specifically starting from Section 3.

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crap will that sucks I couldn't find that my set up was without that info ok no problem just got to redesign the plan to at least L2 and ill need to find out who in my club is a L3 to or if there is a L3cc in the club already but that's a lot of paper work will ill rework it then ill look into the L3 in 2 weeks be cause that's our next launch but that launch even if I was a L2 already I cant fly a L3 do to motor limit

hawlk2004 said:

crap will that sucks I couldn't find that my set up was without that info ok no problem just got to redesign the plan to at least L2 and ill need to find out who in my club is a L3 to or if there is a L3cc in the club already but that's a lot of paper work will ill rework it then ill look into the L3 in 2 weeks be cause that's our next launch but that launch even if I was a L2 already I cant fly a L3 do to motor limit

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Ummm, Do your L1. Plan and do your L2 and nothing wrong with thinking about an L3 project. You should take your time and not rush it. My originally planned L2 rocket is still in paint in the basement. Two altimeters DD, tip to tip lamination and I went with
a 3FNC and motor ejection to git 'er done 9 years ago. Did a lot of DD with H and I motors and tossed in a few J's every now and then. Not every flight has been perfect. The second you think you're a "hotshot expert" you will be bit.

The young people who zip through L1-L3 I've read were involved with rocketry since they were little tykes, very experienced and their sponsors (Taps, L3CC's) were very confident in their skills. There was a recounting of a very skilled young man who did
L1 to L3 in one day. Very extraordinary but he was very well-qualified and prepared. If not, I doubt there would have been a single TAP or L3CC who would have underwritten him.

What's the rush? Kurt

Time for some decaf . Relax and enjoy the ride.

regualer decaf don't make a dif for me but any ways redesigned and it will go easy form 0 to L2 for me just a motor swop and a recharge on the DD and ready to go again
but the L3 im going to start planning tomorrow so I can do research on material like the dif of fiber to carbon fiber

You may not want to hear this, but I would strongly suggest you build a 38mm MMT rocket for L1. Get the cert and fly that rocket a lot. Once you've figured out what you did wrong with that rocket, design and build a 54mm MMT L2 rocket and get that cert. After flying that for a while you'll know what you did wrong on that one and can design and build the L3 rocket.

Reading all the posts here and listening to the guys that have done it is great, but until you've done it all yourself, you just don't know. I equate it to teaching my son to drive. After all the hours in car, and all the explanations of winter driving, he still had no clue until he went sideways on a snow covered road for the first time.

Good Luck and I hope that snow doesn't put you in the ditch.