Do you consider MPR a pre-requisite for HPR?

[Art Upton]

Nothing says level certificate flights have to be "low and slow"; in fact that may actually be just as much of an issue as never finding the rocket again. Seen enough underpowered "large" rockets on mid-power motors crash and burn, or alternatively "large" midpower that are overpowered with large Gs and have their fins ripped off.

But certainly having experience at MPR, especially with the different techniques in MPR and HPR vs LPR, can't not hurt. I would recommend it to anyone. But its not required by NAR or Tripoli.

I'm wondering if either NAR or Tripoli publish a report on number of attempts vs ratio of success/failure.

How do you rip the fins off a MPR rocket with a MAX allowed G80? Also for the other poster, most folks are not certifying on a 38mm Full H either.

Now a G125 [which is an HPR motor] will rip plastic fins off a BT56 sized rocket like the discontinued Eliminator.

I've flown 29mm H motors in the Estes Asender rocket and have the video and altimeter readings on it with plastic fins glued properly with CA glue; meaning no gaps in the fin halves for air to get into. No epoxy or other heavy weight glue at the bottom end of the rocket where it does not belong.

 

[Art Upton]

I would be keeping in mind the relatively low bar to entry into HPR. Fly and successfully recover a H or I motor powered rocket. Looking at it there is very little difference from MPR to something that is H capable. If they flyer has their recovery sorted out then there is probably little to be gained by more MPR flying before going to L1. I mention recovery in particular as it is where a lot of people have trouble, especially with parachute packing for correct deployment. That is where I had troubles, and once I sorted that out L1 was a VERY easy step. L2 and L3 have progressively higher standards of flying and knowledge and skill required.

When I "HPR confirmed" in 1989, I flew an H70 29mm single use motor in a Big Brute. I could then buy a J or K motor or bigger. [But I didn't buy anything over a full H after my flight]

Then they got smart and made testing and cert levels a few years later.

Was TRA 492

 

[techrat]

Well at the METRA launch today we had someone going for his L2 cert. Nice looking Gold and Red rocket that looked like it was 2 stage, but was currently single stage. Anyhow, point is; while I'm sure the young man involved had all the electronics sorted out, that wasn't where the failure occurred. Not long after the launch we see fins fluttering down. The rocket still flew straight, chutes delpoyed properly and frankly, it would have been a success except that his rocket shredded off pieces on the way up. So, the important thing here is to test test test. Never assume that everything is going to as planned.

 

[thzero]

How do you rip the fins off a MPR rocket with a MAX allowed G80?

Balsa fins? Big fins? Poor construction?

 

[Art Upton]

Balsa fins? Big fins? Poor construction?

No, most MPR will use bass or plywood. I have flown a Estes 2.5" rocket on an I205 with only Gorilla Glue to the fin can and only slight yellow glue to the body tube to seal the slots from air getting into them.

After flying it on Fryday at Octoberfest at Jean Dry lake; I had to fly it again on Saturday to prove it flew ok. The body tubes where not glued together as I had to ship it in a box to Fex Ex Los Vegas for hold and pick up.

Simple masking tape held it together.

Too many people try to make small rockets weight too much ....

 

[Art Upton]

Balsa fins? Big fins? Poor construction?

Nope , not "Much" in the under G category at all, all all the weight you want to your rocket at the wrong end of it....

 

[waltr]

Since this is an "opinion" thread, mine is:

Not a requirement to have MPR or even LPR before HPR Cert but to does really help.

Learning is enhanced with a few failures and these are best done with smaller, lighter, cheaper rockets.
Of all the L1, L2 Cert flights I have witnessed, Most failures were with people that had near zero LPR/MPR experience.

The ones that learned their way up to HPR mostly had successful Cert flights.

As to fins shedding, I have seen this happen with an Estes 18mm BP B motor. Also have seem lots of other structual failures on BP A thru E motors. These are most kids building and flying at our local club.
Yes, we examine their rockets and call a 'heads up' flight explaining the rocket may not hold together. Now these kids are learning and their next rocket is better. When they are ready for HPR cert I'll bet they pass first try.

 

[smstachwick]

There is NO studying REQUIRED for the higher qualification of L1 certification.

I used “studying” loosely. Perusing online forums, reading technical documentation, fooling around a bit in OR, even just reading the instructions closely in a kit build.

Strictly speaking, time on the LPR/MPR range would also qualify.

None of these have to be hard or time-intensive.

You seem to be REQUIRING that in your version of your examination of the candidate.

Not at all.

If I knew the candidate well and knew they had the knowledge to fly safely, it’d be a no-brainer to witness. But if I didn’t, my natural interest in other people’s rockets would inevitably lead to a conversation with the candidate about their certification planning process. If the candidate could not walk me through it, that would be a problem.

At a minimum, a candidate should be able to show, demonstrate, or discuss their rocket’s motor retention, stability, initial guidance, anticipated recovery characteristics, and motor selection knowledgeably.

Anyone who has spent any amount of time at a low-power range, or has pursued independent study, or who is working with a competent, qualified mentor, or who read the instructions on the product they’re using, would be able to do this.

The conversation might look and sound something like this:

“May I take a look at your rocket?”

“Sure!”

*verifies motor retention visually

*verifies presence of appropriately-sized launch lugs, rail hardware, or visual evidence the candidate has brought some other system like a tower

“How high do you think it will go?”

“I’m aiming for 1700 ft. That’s roughly what the sims spit out and it tracks with the test flight I did with a G80.”

…and so on. Softballs. Casual range talk between a guy showing off his rocket to an impressed (or concerned) onlooker.

The goal would not be to administer the L2 test, the goal would be to determine the candidate’s preparedness for exploring the ins and outs of L1.

However, if the candidate were to reply with something way off-base like “No clue. We’ll find out, won’t we?”, that would be cause for concern. I would ask that candidate to explore a bit with whatever tools they have at their disposal to figure out the solutions to essential range safety considerations, and if I found it prudent I may even offer a nudge in the right direction. The candidate could either accept that and have me on their team, or certify with somebody else.

If gaining the requisite knowledge means they would have to go through the launch event without certifying…tough luck. They can learn from it and plan better.

The way I see it, a certification witness in this situation can either weed out or foster. High-power launches are fun and I have no intention of pulling up the ladder behind me once I’m there. But when the cards are down and my name is on the paperwork, I want no part in the causality chain of a disastrous flight that should not have been made. Big rockets can bite.

But don't do it and then say your rocket is the wrong colour.

Your imagined scenarios are nothing of the sort I have any intention of being part of. They are entirely hypothetical and academic, fully invented by you, and not grounded in any sort of reality I have ever witnessed on the range.

As a side-note: paint scheme would be a valid topic of conversation. Accurate military camouflage or nature patterns can make a rocket hard to see. Asking a candidate who has painted a rocket this way if they have thought of and planned for that is valid. I don’t think I would refuse witnessing on that but the candidate may decide some further work is in order.

The RSO and the LCO, examine the rocket and make the decision whether to launch or not. Not the witness.

It is the witness’s decision whether to be part of a certification team. You are confusing my hypothetical willingness to deny witnessing with my willingness to interfere with range personnel. Review my position again, I never made any such implication. That’s not how certification works.

Perhaps have a chat with your local LCO or RSO regarding variable examination standards at your next launch.

No.

Safety distances and procedures, RSO and LCO keep things safe.

Range safety is a universal responsibility. I have shouted “wait!” during final countdown on one occasion: the matter was cleared up in about 5 seconds and the rocket went off without a hitch.

I’ve also put people in the know regarding site-specific safety rules. Always gently of course, I just work under the assumption they missed the safety meeting.

And for any certification flight I've ever witnessed, HEADS UP would be announced.

ROC (my de facto primary HPR club) has flight cards for certification flights printed on red paper. They don’t make a lot of hoopla about it, they just ask why the card is red (to make sure it’s not for some other reason) and certification witnesses are called up over the PA.

my 50c worth.
I'm done on this subject now. Hooray.
Ends.

Me too. Please don’t bring this drivel here again, I’m so tired.

 

[OzHybrid]

But not too tired to post a line-by-line breakdown where you contradict yourself again.

 

[Hobie1dog]

OP, do you have your answer?

 

[mtnmanak]

A somewhat tangent answer/discussion from the original question is not so much the rules, but the inconsistency in which they are applied. I have watched TAPs absolutely grill a Level 1 candidate and refuse to cert them if they have not flown any MPR rockets. I have also been at launches where there were Level 1 cert flights that were virtually unobserved and still certified (this happens more with NAR Level 1 certs since pretty much anyone with a NAR cert can sign off on those flights). Most cert flights probably fall comfortably in the middle ground, but there are extremes.

I don't think this would be too hard to fix. Why not require the TAP Pre-Flight Data Capture form for every Cert flight, not just L3 flights? The form is very minimal. All it really asks of the flier is to show their work and understanding of basic rocket stats like dimensions, weight, T:W, CP, CG, expected velocity, and altitude. These questions are basic for every cert flight, not just L3. If a flier can fill out that form, I would think the comfort zone of letting them fly their cert rocket goes up considerably.

 

[anbhtblr]

Well at the METRA launch today we had someone going for his L2 cert. Nice looking Gold and Red rocket that looked like it was 2 stage, but was currently single stage. Anyhow, point is; while I'm sure the young man involved had all the electronics sorted out, that wasn't where the failure occurred. Not long after the launch we see fins fluttering down. The rocket still flew straight, chutes delpoyed properly and frankly, it would have been a success except that his rocket shredded off pieces on the way up. So, the important thing here is to test test test. Never assume that everything is going to as planned.

Where was the RSO, or was the construction questioned but the launch allowed. I've had RSOs stop me from launching construction (mechanical, not adhevise, material joining) that later proved MORE than andequate. IMO RSOs should question doubtful or unusual contrustion, but NOT ALWAYS stop the launch. Construction technique doesn't get proven by sitting on a bench.

 

[rcktnut]

Just say'in for us guys becoming BARs before the favorable ruling on APCP I'm sure most of us did have experience with MPR before getting into HPR. I certainly did for years before deciding to jump through all the hoops to get a LEUP. MPR was a fun step up from LPR.
Deciding what to do now is much easier.

 

[smstachwick]

But not too tired to post a line-by-line breakdown where you contradict yourself again.

Where?

 

[greylond]

My lpr/mpr experience was not sufficient alone for hpr. I don't think more experience would have really helped, because I was selecting motors and delays off of the kit package without any real understanding of how the figures are arrived at. I never ran a simulation. I didn’t need to understand stability to fly a kit, the guy who designed it already did all the work. My club has this rather difficult list of lvl. 1 certification requirements above and beyond selecting a motor off the package. In hindsight, I learned more checking these boxes than I had in all my kit building and flights. If I wasn't motivated enough to learn, then maybe the hobby would be safer without me flying hpr. Now I can scratch build and recover hpr with confidence and safety. I would highly recommend these requirements just because they made the hobby much more enjoyable. Yes, experience is valuable, but not essential. In my case, it was only the same uneducated repetition. So not that valuable at all.

 

[OzHybrid]

My lpr/mpr experience was not sufficient alone for hpr. I don't think more experience would have really helped, because I was selecting motors and delays off of the kit package without any real understanding of how the figures are arrived at. I never ran a simulation. I didn’t need to understand stability to fly a kit, the guy who designed it already did all the work. My club has this rather difficult list of lvl. 1 certification requirements above and beyond selecting a motor off the package. In hindsight, I learned more checking these boxes than I had in all my kit building and flights. If I wasn't motivated enough to learn, then maybe the hobby would be safer without me flying hpr. Now I can scratch build and recover hpr with confidence and safety. I would highly recommend these requirements just because they made the hobby much more enjoyable. Yes, experience is valuable, but not essential. In my case, it was only the same uneducated repetition. So not that valuable at all.

These are High Power Certification rules. As they are club DOCUMENTED rules, I've got no issue with them. What I do have an issue with is undocumented rules being imposed by others. If the rules are documented, you know what they are. In this case, a lower standard requirement being exceeded by an individual imposing their own set of standards.
Of course, as has been pointed out, that individual would not be required to witness your flight. Probably best to avoid an individual who would not agree to witness a flight that complied with the rules.

 

[OzHybrid]

Where?

Everywhere.

 

[greylond]

Absolutely. It would be frustrating to the extreme if someone moves the goalposts arbitrarily!

 

[anbhtblr]

Please elaborate on "self reloading hybrid". I understand the words, but the meaning of the phrase is foggy.

 

[thzero]

Nope , not "Much" in the under G category at all, all all the weight you want to your rocket at the wrong end of it....

Ok dude

 

[novahobbies]

Not really necessary, but it IS a fun middle-road option. For me, since I don't really have the space for HPR, MPR is a fun alternative. Plus I can fly a MPR 2 or 3 times for the same price as a single HPR launch. And I can use more advanced building techniques with MPR that aren't really needed (or even useful!) In LPR situations. So no, it's not really a pre-requisite. But it IS a fun stepping stone.

 

[Art Upton]

I built a Low Power Semroc Parts based down size model of the Loc Bruiser in their close to bt60 size tube.

I built the fin can and motor mount and painted the fins on the mount. I then painted the body tube and slotted it to fit over the fin can and seal it up.

HPR/MPR techniques I did on the Low power rocket. It was fun.

 

[Ez2cDave]

I consider it a nice addition to experience, but not requisite.

Really ?

A first-time rocketeer shows up on the field. and flies a Micro-Maxx ( his first rocket ever ) . . . Strolls over to an on-field vendor and buys a 3" diameter LOC kit, some 5-minute epoxy, and "slaps it together" in about 30 minutes . . . Then, he goes to the Motor Vendor, buys an "H" motor and wants to Cert Level 1, with plans to take the test immediately after the Level 1 Cert and to go for Level 2, both on motor ejection ( 1 Micro-Maxx to an "H" to a "J" motor, all in about an hour ) . . . Would you be willing to allow that ?

One has to crawl before they learn to stand . . . They have to stand before they learn to walk . . . They learn to walk before they learn to run . . . A basic "progression", same for Rocketry.

 

[OverTheTop]

Really ?

A first-time rocketeer shows up on the field. and flies a Micro-Maxx ( his first rocket ever ) . . . Strolls over to an on-field vendor and buys a 3" diameter LOC kit, some 5-minute epoxy, and "slaps it together" in about 30 minutes . . . Then, he goes to the Motor Vendor, buys an "H" motor and wants to Cert Level 1, with plans to take the test immediately after the Level 1 Cert and to go for Level 2, both on motor ejection ( 1 Micro-Maxx to an "H" to a "J" motor, all in about an hour ) . . . Would you be willing to allow that ?

The rules do in fact allow that. Might he be successful with the cert attempt? Maybe. It isn't how I did it, but it is the rules. Remember we have the safety code to keep distance between us and his rocket. The RSO will check it to make sure it is reasonably safe to fly.

As I mentioned upthread, the bar to entry in HPR is really quite low.

 

[OzHybrid]

Really ?

A first-time rocketeer shows up on the field. and flies a Micro-Maxx ( his first rocket ever ) . . . Strolls over to an on-field vendor and buys a 3" diameter LOC kit, some 5-minute epoxy, and "slaps it together" in about 30 minutes . . . Then, he goes to the Motor Vendor, buys an "H" motor and wants to Cert Level 1, with plans to take the test immediately after the Level 1 Cert and to go for Level 2, both on motor ejection ( 1 Micro-Maxx to an "H" to a "J" motor, all in about an hour ) . . . Would you be willing to allow that ?

One has to crawl before they learn to stand . . . They have to stand before they learn to walk . . . They learn to walk before they learn to run . . . A basic "progression", same for Rocketry.

Yes. If they are compliant with the rules. And under Tripoli, those are the rules.
If the rules need changing, change them! Do not apply your own made up rules.

If the rocket supplied to the RSO passes examination and the flyer does not break any rules, then, if it is a safe rocket, allow it to launch. All cert flights should be announced as a heads up launch.
As stated previously, clubs can impose club rules to a higher standard. But they should be in writing so the examinee has a fair chance of knowing what they are. NOT someone making them up on the day. However well-intentioned an individual may think they are being, consistency of rules application provides a level playing field for all.

 

[nict]

Yes. If they are compliant with the rules. And under Tripoli, those are the rules.
If the rules need changing, change them! Do not apply your own made up rules.

If the rocket supplied to the RSO passes examination and the flyer does not break any rules, then, if it is a safe rocket, allow it to launch. All cert flights should be announced as a heads up launch.
As stated previously, clubs can impose club rules to a higher standard. But they should be in writing so the examinee has a fair chance of knowing what they are. NOT someone making them up on the day. However well-intentioned an individual may think they are being, consistency of rules application provides a level playing field for all.

Can we have this thread locked? @RocketScientistAustralia explained it perfectly. The troll needs to get a time out.

 

[smstachwick]

Can we have this thread locked? @RocketScientistAustralia explained it perfectly. The troll needs to get a time out.

I have never once been accused of trolling for voicing purely rocketry-related opinions. It simply doesn’t match with community standards on the site.

I will repeat: NO Tripoli or NAR member is obligated to serve as a certification witness under any circumstance, and can refuse for any or no reason. We are also under no obligation to be consistent on these decisions or in our reasoning

If you can find NAR rules to the contrary, I’ll gladly eat my words, but requesting mod action simply because you think I’m wrong is low. If you’re truly confident I’m breaking the forum rules, smash Report.

It’s lower still with me being not (yet) certified. Haven’t the two of you wasted enough effort on this question?

 

[OverTheTop]

If people want to hold themselves to a higher standard then that is fine. They should not impose their requirements over and above the actual requirements unless there is a very good reason. Remember that the HPR rules have been debated in far higher echelons of rocketry than a thread on a forum, and by flyers with far more experience than most here.

Imposing another layer of rules or conditions is just being peremptory.

 

[smstachwick]

If people want to hold themselves to a higher standard then that is fine. They should not impose their requirements over and above the actual requirements unless there is a very good reason.

This entire discussion seems to have arisen out of a confusion between “should” and “can”, “dangerous” and “inconvenient”. My case is that I that I could and would impose a higher standard if I were witnessing (which I’m not), but I would only do this with what I consider good reason and not arbitrarily. If my good reason is safety or liability-related, then I should.

That stance has always been fully consistent and has not changed.

If the others can’t or won’t accept this, or disagree with me on what would constitute a very good reason…tough. Same with a flyer; lots of others would be willing to help. I’m under no obligation to come to an agreement.

I do object to being accused of breaking forum rules though. My words have been sharp but not vicious, nor is my objective to stir up trouble. It’s always been to improve understanding, both my own and others, which is why as involved myself in this tangent for so long. So far understanding seems elusive though, which is frustrating.

 

[OverTheTop]

If my good reason is safety or liability-related, then I should.

Is your reasoning better than the RSO or LCO, or all the rules previously debated and defined? What can you show to prove your moral high-ground is the correct stance? Statistics? Something else? I am curious to know.