TRA Level 3 Cert Question

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MurphysLaw42

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Hey all,

First off, I've lurked awhile around here and I have to say y'all have been lifesavers on my previous builds, so thanks to the community at large.

Second is my question:
I want to go for my L3, but a question on the paperwork process has me halted. For the preflight stuff, I know you have to document your build and show that it's going to hold up. I'm going to be doing a kit simply because I don't have the space or tools to scratch build one at the moment. Design reports are pretty much my college career in a nutshell, so I feel good there. My question is: Could I build it with the intention of flying large L2 motors and then, if I feel confident about the build, submit my documentation to the requisite reviewers from the Technical Board? Or do I have to build it with the intent of starting at my level 3 and not fly it at all before getting the design approved? I've done some digging but haven't found anything that really answers that question.

Any help at all would be appreciated.
 
A shake down flight IMO is the responsible route if possible. Can't see anyone getting upset with you there. I would do the paperwork and mention that part of the process will be a test flight first. Get all your approvals first. If you do have an issue with the flight then fix it, make a note of the issue and what you did to correct it in your paperwork. It's all part of the design process and it shows you are aware that issues can crop up and can deal with them. All of which shows that you earned that certification in the end.
 
Hey all,

First off, I've lurked awhile around here and I have to say y'all have been lifesavers on my previous builds, so thanks to the community at large.

Second is my question:
I want to go for my L3, but a question on the paperwork process has me halted. For the preflight stuff, I know you have to document your build and show that it's going to hold up. I'm going to be doing a kit simply because I don't have the space or tools to scratch build one at the moment. Design reports are pretty much my college career in a nutshell, so I feel good there. My question is: Could I build it with the intention of flying large L2 motors and then, if I feel confident about the build, submit my documentation to the requisite reviewers from the Technical Board? Or do I have to build it with the intent of starting at my level 3 and not fly it at all before getting the design approved? I've done some digging but haven't found anything that really answers that question.

Any help at all would be appreciated.

Submit a build idea to your tap for review is the proper route.
 
I have not yet taken this step but I believe they are supposed to be able to review during the build process.

That does not mean you cannot use it for L2 beforehand, of course. It simply means you should do the paperwork and review during the build of the rocket that eventually goes for L3.
 
Submit proposal to TAPS. Get their approval before construction.

Construct and document. There are numerous past L3 cert documents on the web you can use as examples.

Get TAPS approvals before flight.

Fly cert. I do not believe in a test flight with an L. At this level you fly the cert with the expectation that it will succeed.
 
I am a TAP. I flew a large 7.5" rocket for years on clusters before I decided to do my L3. Both of my TAPS inspected rocket prior to flight. As a TAP, I would have no problem inspecting an already built rocket for certification.
 
Thanks guys, good stuff to think about. I think for now I'm going to be happy with my L2, still lots of fun to be had there. Once I get the hang of the bigger builds I think I'll try my hand at certifying. I'll still document the whole process just in case I change my mind and the TAPs don't have any objections, but I'm going to take it slow and not make any mistakes because I jumped in before seeing how deep the pool is.
 
Fly cert. I do not believe in a test flight with an L. At this level you fly the cert with the expectation that it will succeed.

Funny you say that because even Martin Marietta did test flights. Just a little joke based on your forum name. I think it's fine either way, shakedown flight or not. But just because someone flies an L before there L3 Cert doesn't mean they don't expect there flight to be successful.
 
Thanks guys, good stuff to think about. I think for now I'm going to be happy with my L2, still lots of fun to be had there. Once I get the hang of the bigger builds I think I'll try my hand at certifying. I'll still document the whole process just in case I change my mind and the TAPs don't have any objections, but I'm going to take it slow and not make any mistakes because I jumped in before seeing how deep the pool is.

Why not find 2 taps and propose a build for a future project? Use the system. Allow us to review your panned build and make suggestions to help you be successful. I had a Cert attempt this last weekend that was already built. He failed due-to fin flutter. Had he contacted one of us before he built the rocket, we could have told him that 1/8" G10 was to thin for the rocket. FYI: from the tripoli site-At least one pre-flight TAP member must physically inspect the project in a nearly complete state before being approved for flight. You can't do that on a built rocket.
 
I had a Cert attempt this last weekend that was already built. He failed due-to fin flutter. Had he contacted one of us before he built the rocket, we could have told him that 1/8" G10 was to thin for the rocket.

You still could have told him before the flight that the fins were too thin.
 
I was there for that, actually. What's the best way to go about selecting and contacting TAPs with a proposal? And what needs to go into said proposal?
 
FYI: from the tripoli site-At least one pre-flight TAP member must physically inspect the project in a nearly complete state before being approved for flight. You can't do that on a built rocket.

Could one of the TAPs in the thread please clarify what is intended by inspecting the project in a nearly complete state? I took that to mean "built, but not prepped" - i.e., be prepared to disassemble the av-bay, show separation points, etc. I ask because I'm at least a couple of hundred miles from my nearest TAP and pictured this inspection happening at a launch.
 
I want to be able to look at everything. See how it all fits together, see inside the e-bay and how it's set up, wiring, check the fit of the nosecone and airframe separation points, etc. I do not need to see the interior fin fillets (although photos are nice) but if I ask a question on how you did them you need to know the answer. To me that's nearly completed.


I have seen more than one L3 project approved by two TAP members and then flown on the same day at LDRS. It seems to me that more flight failures happen this way than when a TAP member is involved from the beginning. That's not empirical evidence just personal observation.
 
Cool, that's how I was expecting it to work. Thanks for the info!
 
Good plan. I'm designing my L3 (NAR) rocket explicitly to fly on certain 75mm L and M motors. L then M is the route I plan to go - did the same for my L2, flew the same configuration on I motors and then flew on a J for the L2.
 
I want to be able to look at everything. See how it all fits together, see inside the e-bay and how it's set up, wiring, check the fit of the nosecone and airframe separation points, etc. I do not need to see the interior fin fillets (although photos are nice) but if I ask a question on how you did them you need to know the answer. To me that's nearly completed.


I have seen more than one L3 project approved by two TAP members and then flown on the same day at LDRS. It seems to me that more flight failures happen this way than when a TAP member is involved from the beginning. That's not empirical evidence just personal observation.

I agree. I accept photos of internal fillets. If you are doing a L3, let us help you be successful. Ask us about the planned build. I think I have a 100% success on this method, and I bet it is about 70% in the prebuilt method.
 
Regarding pre-cert test flights on smaller motors, what do you guys see as the benefit? To me it seems like the most likely points of failure - deployment failure, electronics snafu, CATO, tangled chutes - are not at all motor size dependent. Pretty much the only failure modes a test flight would catch are a) a structural problem that is obvious but not fatal on the small motor but fatal on the larger b) a badly modeled rocket that is marginally stable on the smaller motor. Both of those seem pretty rare, especially if you're experienced enough to be attempting an L3. And if you're not confident in your set-up process you can (and should) always dry-run until you are. Putting a live motor in for your "rehearsal" just makes any mistakes costly. I guess maybe it gives you a trial run without the stress of a cert flight, but then again having extra eyes on you for a complex rocket's first flight might save you from a big mistake.

So it seems like flying a pre-cert flight is almost doubling your risk - isn't L flight + M flight riskier than M flight alone? Lots of extra risk and cost for minimal benefit, especially since there's no real penalty for failing your cert flight. It would really stink to lose your cert bird on a "test" flight.

And yet "do a test flight" seems like common advice / "common sense" - what am I missing?

I may be speaking from a place of sadness since I recently lost my MDRM on a "test" flight for an L1 cert. Next one's getting fed a DMS H for its maiden voyage :)
 
I see what you're saying, and you're correct that flying the rocket on an L before flying the cert attempt on an M creates the possibility that the rocket will be lost before the cert attempt is even made. In my case, I want to approach the certification process as a learning process, not just to maximize my odds of succeeding on the first try. An L flight will give me flight data that shows me how well the finished rocket matches my simulations, beyond whether it works or not.

Edit: I'll add that in my specific case, I don't have a TAP available in my local club, so my certification flight will be at an out-of-town event like AirFest or Midwest Power. So I may likely have an opportunity for a "trial" flight with my local club before my certification opportunity. That's weighing into my plan as well.
 
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I elected for a 'trial run' flight before my first L3 attempt and flew my Wildman Darkstar Extreme on an L for its first flight, with TAP concurrence. I learned a lot from that flight and changed the shear pin configuration as my main came out at apogee despite the 2-56 nylon shear pins used. The 4-40 nylon ones did the trick (and more 4f for insurance), as well as larger airframe vent holes. I'd rather make mistakes with a $143 motor than a $200 one.

Then again, you cannot insure yourself from every bad possible outcome with a pre-L3 flight. For my first L3 attempt (M1297W), I left the main chute disconnected from the recovery harness. Got lucky, no damage, but also no cert. However, got it right the second time!
 
...a TAP member to look at it during construction? Really? So that guy out in the boonies can't become 3rd level because the nearest TAP member is 500 miles away? Horsehockey, think I'll be skipping going to 3rd level this time around. My two TAPS first time around was Jim Cornwell and our own MClark. I am in Idaho, they are in Arizona, the 3rd line was signed by Karl Baumann. 500 pound thrust Kosdon M2240 that I bought from Frank Kosdon and guess what? It all hung together just fine without a "mentor". I know that there are TAP guys up here but I don't feel like having some guy with a ten thousand number looking over my build critiquing my rocket....
 
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Thanks for the replies, though I'm not totally sold...

An L flight will give me flight data that shows me how well the finished rocket matches my simulations, beyond whether it works or not.

But an M flight lets you do the same, no? No one says you're not allowed to learn from your cert flight :). But you're right, the point of launching rockets is, well, to launch rockets, and if learning more from more launches is your goal, then absolutely. I'd just be paranoid about a purpose built for certification rocket being used on a flight that won't certify it. I guess that only really applies to L3 though, since all the pre-build documentation sounds like a lot of work to redo if you crack up before you certify.

I elected for a 'trial run' flight before my first L3 attempt and flew my Wildman Darkstar Extreme on an L for its first flight, with TAP concurrence. I learned a lot from that flight and changed the shear pin configuration as my main came out at apogee despite the 2-56 nylon shear pins used. The 4-40 nylon ones did the trick (and more 4f for insurance), as well as larger airframe vent holes. I'd rather make mistakes with a $143 motor than a $200 one.

Does an apogee deployment automatically generally disqualify a cert flight, assuming the chute fully deploys and it still comes down safely? It's not on the list of automatics disqualifications on Tripoli, unless it drifts too far - is that something most TAP members would call a disqualification? This is an honest question - I'm a long way from doing L3 but I'd like to do L2 not too long from now, and it might inform my rocket choice.

Motor Cato
Excessive Damage
No recovery system deployment or tangled recovery system deployment
Rocket drifting outside the specified launch range
Components coming down not attached to the recovery system.
Any other violation of TRA safety code associated with this particular flight.
Any other legitimate reason the TAP member deems merits non-certification.

That might be a good thing to think about, I guess, if you're not 100% on your charge/shear pin configuration it might be dicey going higher and risking more drift. Of course, too much shear pin and your rocket's just as dead, whether you launched it on an L or M (or an H). As for the $143 v. $200 motor - eh, I figure theres a lot of expensive stuff in there other than just the motor, and as long as it goes up, you've gotten all your value out of the load anyway, right? It did its burny-smoky job, coming down is on you :wink:
 
...a TAP member to look at it during construction? Really? So that guy out in the boonies can't become 3rd level because the nearest TAP member is 500 miles away? Horsehockey, think I'll be skipping going to 3rd level this time around. My two TAPS first time around was Jim Cornwell and our own MClark. I am in Idaho, they are in Arizona, the 3rd line was signed by Karl Baumann. 500 pound thrust Kosdon M2240 that I bought from Frank Kosdon and guess what? It all hung together just fine without a "mentor". I know that there are TAP guys up here but I don't feel like having some guy with a ten thousand number looking over my build critiquing my rocket....

What does the ten thousand number have to do with anything? Do you think that makes them less worthy than a guy with a lower number?
 
...a TAP member to look at it during construction? Really? So that guy out in the boonies can't become 3rd level because the nearest TAP member is 500 miles away? Horsehockey, think I'll be skipping going to 3rd level this time around. My two TAPS first time around was Jim Cornwell and our own MClark. I am in Idaho, they are in Arizona, the 3rd line was signed by Karl Baumann. 500 pound thrust Kosdon M2240 that I bought from Frank Kosdon and guess what? It all hung together just fine without a "mentor". I know that there are TAP guys up here but I don't feel like having some guy with a ten thousand number looking over my build critiquing my rocket....

I'm with you on that Dave. Some of us live far away from TAPs and carting a rocket back and forth for "inspection" is ludicrous. I will say in that regard, copious photos and I even did videos of some of the construction tasks go a long ways. I have two rockets that are L3 capable and ruminating over which one to use.

Photos of internal fillets? For gosh sakes Chris how can you get a decent shot of an internal fillet on a 4 inch glass rocket with a 76mm motor mount? It's not
doable unless one has a fiberoptic ureteroscope they can use before they put the aft centering ring on.

I inject my fillets from the bottom with rubber tubing and a syringe using liberal amounts of epoxy. Both of my L3 capable rockets used Duralco 4525B and 4525IP
epoxy which is as about as bullet proof as one can get.

As I ruminate, I'm considering doing a L flight if I can get some 76mm hardware to do it. Document/video the flight and have that for ammunition in the document
pack.

Actually, as far as having the candidate break down the rocket and explain everything from nosecone tip to tail is perfectly valid. I believe the flier should be able to explain everything including the wiring of the ebay and all of the construction features contemporaneously. Put it all back together and go fly. If a person can explain everything to the reviewing TAP, it's a heck of a lot better than a bunch of gobbledygoop in a paperwork pack. I'm not slamming the requirements in the cert paperwork. That isn't that difficult to pull off. I know one candidate that had to bring his rocket to he TAP 6 times for "inspections" before he'd sign off on it. Granted that was in the dark ages 7 years ago but totally uncalled for then and uncalled for now. Kurt
 
I'm with you on that Dave. Some of us live far away from TAPs and carting a rocket back and forth for "inspection" is ludicrous. I will say in that regard, copious photos and I even did videos of some of the construction tasks go a long ways. I have two rockets that are L3 capable and ruminating over which one to use.

Photos of internal fillets? For gosh sakes Chris how can you get a decent shot of an internal fillet on a 4 inch glass rocket with a 76mm motor mount? It's not
doable unless one has a fiberoptic ureteroscope they can use before they put the aft centering ring on.

I inject my fillets from the bottom with rubber tubing and a syringe using liberal amounts of epoxy. Both of my L3 capable rockets used Duralco 4525B and 4525IP
epoxy which is as about as bullet proof as one can get.

As I ruminate, I'm considering doing a L flight if I can get some 76mm hardware to do it. Document/video the flight and have that for ammunition in the document
pack.

Actually, as far as having the candidate break down the rocket and explain everything from nosecone tip to tail is perfectly valid. I believe the flier should be able to explain everything including the wiring of the ebay and all of the construction features contemporaneously. Put it all back together and go fly. If a person can explain everything to the reviewing TAP, it's a heck of a lot better than a bunch of gobbledygoop in a paperwork pack. I'm not slamming the requirements in the cert paperwork. That isn't that difficult to pull off. I know one candidate that had to bring his rocket to he TAP 6 times for "inspections" before he'd sign off on it. Granted that was in the dark ages 7 years ago but totally uncalled for then and uncalled for now. Kurt

When I did my L3, I hauled a built booster 5 hrs for inspection. As for the photos on a 4" rocket, that's easy.....I live on the east coast and those size rockets cannot be used for L3 flights at most fields.
 
When I did my L3, I hauled a built booster 5 hrs for inspection. As for the photos on a 4" rocket, that's easy.....I live on the east coast and those size rockets cannot be used for L3 flights at most fields.

A 4" rocket is going north above 10k' so an appropriate venue would be needed. Plus it behooves the flier to have a bulletproof tracking remedy. Some can't store large projects so small diameter might be the only practical option. I concede if the rocket is large diameter, it would be easy to document the internal fillets photographically.

Five hour drive for an inspection? I would say that's impractical unless it was inspected and then flown. I would think getting the documentation to both TAPS in advance and make plenty of phone calls for clarification would suffice. If both TAPS were available for
preflight inspection at the launchsite they could go over everything there as they should have adequate prior knowledge from the previously submitted papwerwork. If one TAP feels the paperwork and details were adequate and he/she can't "witness" they
could confer with the "witnessing" TAP and proceed accordingly. If the one TAP is uncomfortable with that arrangement, the candidate would simply have to go to a launch where two TAP's are available for final inspection. Of course prior arrangements would need to be made so
the TAPs could get the documentation well before hand for review. As always, if the TAP doesn't feel the rocket is safe for flight, that's the law. It don't fly. Kurt
 
I think that anytime a person can test with a good size L motor in a rocket before taking the step to install an M and, Cert. is a great idea. As a matter of fact i've recommended it for many years...

A person should have a good confidence in their electronics, charge sizing (including ground testing) recovery system and, overall assembly of their rocket before the big day. Not just on that day.

When stepping up to L3 you find (and, not always) that some people are not used to the bigger airframes and, weights that they encounter when doing this...You have to have confidence, because in the end it IS up to the flyer to make sure that Safety and, Security of ALL components are spot on whether flying an Estes motor or a full on M and, above.

We all know that anything can happen, we expect that but, when you feel that you can do this it really boosts the whole process along much more smoothly. Plus, i know alot of people like to get it out of the way then put on the killer paint/graphics...for the one that counts.

When choosing a TAP(s). Remember you can choose anyone but, when you do keep in consideration their location and, the fact that if they can inspect your project...a potential issue or issues can most likely be averted long before you show up at the field.

In the end you have to please your TAP's, both of your TAP's. We all know the rules and, sometimes that leads to different interpretations...but, you have to get it right with who you choose.

A little known fact- You can fire me....I can fire you...If i think your a Safety hazard...Were going to talk...We need to fix this issue/problem. If you don't want to listen or you know everything (trust me I don't....) Then i got to move on but, remember that a can of worms opened up by having a TAP refuse to help you may be worse with the next chosen one.
Trust me, i'm actually pretty easy to get along with. I do know some TAP's that are as coarse as 40 Grit sandpaper and, will really ride you.

In the end you need to feel that you have learned something in the whole deal....Feed off your TAP's, ask questions...more questions....search for the answers, find the answers....keep looking....keep learning.

Never stop learning. Keep striving to answer all the questions that may pop up. Use your mind and, your HANDS to construct safe, reliable rockets.

It is very humbling to be in this position...requested by some of my peers but, whats more humbling is to know that some people i know would make the greatest TAPS if only they had the attitude, time and, projected the effort.

I STILL turn to fellow friends on occasion for advice....Trust me, it's a learning curve with a few sharp turns along the way.

Good Luck on your L3! ;)
 
What does the ten thousand number have to do with anything? Do you think that makes them less worthy than a guy with a lower number?

It means I want nobody looking over my shoulder at all and these days the preponderance of the active club IS above 10,000. I'm saying I got nothing to learn from them...well, maybe a little...but I will consult those with nice, low numbers like my own or lower...not people that learned from them.... Like Isaac Newton said, to paraphrase, "They stand on the shoulders of giants..."

It's like...do you know exactly who it was that first used shear pins? Lance Griffin and Ron Urinsco. The rocket was deliberately made very heavy to simulate a "real" rocket to test a 60 foot rail launcher. They wanted the weighted nosecone to stay on so they used styrene rod, poked through holes they drilled right before launch. The flight was successful :)
 
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