Accidentally Blurring the MPR/HPR Line

[smstachwick]

Certification has three steps:
L1 - just another rocket.
L2 - an easy quiz followed by just another rocket.
L3 - A take home essay test and just another rocket.

I like this.

Unfortunately my Just Another Rocket has been delayed by my annoying perfectionism and ruthless self-criticism. Time to Just Do It (TM)

 

[jqavins]

Certification has three steps:
L1 - Just another rocket that costs a little more.
L2 - A little test and an expensive rocket.
L3 - A lot of documentation and, what the hell, I can put off retirement for another year.

 

[thecapotc]

Ha-hah, hooked another one! [EVIL_GRIN]


THE CAPtain Of The [fire] Company?

Nope just a Lt. but I am a 4th generation volunteer fire fighter. It’s actually from my high school programming class username. THEcapot(osto)c(hristian)

Fun times programming in Turbo PASCAL on one of those first candy iMacs running a windows emulator to run the DOS program to use the text book last printed a decade before I was born.

 

[bad_idea]

In my opinion, it is because our community has historically been much more deliberate about self-regulating that we didn't get caught up in the drones-for-christmas overreaction.

There is something to be said for the discretion and self-regulation inherent in a hobby that we all know could easily scare normal people to death. (What about the airliners?, etc.)

 

[Neutronium95]

I wouldn’t worry about it too much. There’s nobody hidden behind bushes waiting to bust you for 1505 grams. Thank you for caring and doing the right thing!

When I was a kid I built a rocket that flew on 4 E9 motors. I flew it at a bunch of launches, some HPR, some not, before I got my Jr. L1. Only after a few years did I realize that I'd been exceeding the propellant mass limit for Class 1 rockets the entire time.

 

[rcktnut]

When I was a kid I built a rocket that flew on 4 E9 motors. I flew it at a bunch of launches, some HPR, some not, before I got my Jr. L1. Only after a few years did I realize that I'd been exceeding the propellant mass limit for Class 1 rockets the entire time.

DON'T FEEL TO BAD ABOUT IT!!
After expressing my dissent in this thread about the current classification of what is HPR and MPR, I've been doing some research on when and why weight was involved in determining what is a MPR and HPR flight. Looks like weight was always involved. So with the new classifications we gained 1 thing, MPR flights and a few HPR flights no longer need to notify ATC, which for MPR nobody most likely never did anyway. I never knew there was a 16oz. limit at one time requiring ATC notification if over.
When I became a BAR (41 years old) 27 years ago as well as some of my friends we were stuck in MPR for years due to ATF regulations and if asked if we did what is outlined in red below we would have to take the 5th. I'd like to know who really did that!



1 'Large Model Rockets' is a term used in the FAA FAR 101 regulations. It
refers to NAR/NFPA model rockets that are between 454 and 1500 grams
(1 to 3.3 pounds) total liftoff weight or contains more than 113 grams
but less than 125 grams of total fuel.

A. FAA Regulations:
* Rockets containing less than 113 grams of total fuel and weigh
less and one (1) pound do not require any type of FAA notification
and are not restricted by the FAA except where they pose a threat
to aircraft.
* FAA "large model rockets" (see the definition in #1, above)
require that the nearest Air Traffic Control center (ATC) be
notified of the launch between 24 and 48 hours prior to the
launch. This is notification and not permission. In the U.S., try
calling 1-800-WX-BRIEF to get the number of the ATC center nearest
you.
* FAA High power rockets (weighing more than 3.3 pounds, containing
HPR motors, or containing a total of more than 125 grams of
fuel) require a formal waiver be approved by the FAA and activated
prior to the launch. Refer to the full r.m.r FAQ (dated 1 Oct 94
or later) for more complete details.
* NOTE THAT THE FAA DOES NOT PLACE ANY RESTRICTIONS ON FUEL-PER-
MOTOR OTHER THAN THE TOTAL LIMIT OF FUEL. HOWEVER, MOTORS WITH
MORE THAN 62.5 GRAMS OF FUEL ARE HIGH POWER ROCKET MOTORS AND
REQUIRE HIGH POWER CERTIFICATION TO FLY. This does allow HPR
certified flyers to conduct low-end HPR launches (with up to about
240NS composite motors) without having to obtain a waiver.
* Remember that HPR waivers, ATC notification and high power
certification are all separate issues and must all be properly
followed.

Safety code in 1997 Estes catalog note #4 Then RH bottom of page. Wonder why that was side lined/ not included with #4. I never seen it.

 

[Raythain]

The lack of bushes at our launch site is a plus since the only thing for the rocket police to hide behind are some grass clippings in case we pick up a couple extra grams along the way.

I’ve usually found that the rocket police sit a table and have a badge that reads RSO. At least rather than arresting you they just make you take the walk of shame back to your range box.

 

[cbrarick]

i'm not for intentionally breaking the rules, however, that said I have to wonder

"What percentage of the people who have freaked out over this have NEVER exceeded the speed limit, not even 1 mph"

at worse this was a teachable moment.

 

[OzHybrid]

The rules you have to comply with are from multiple sources. Tripoli and NAR do a good job of distiling them into a coherent set of easy to use guideliines. However there may also be local rules from the landowner or others. This is where the local club comes in to make those rules make sense with the others.

 

[cbrarick]

The OP is a 4h person flying in a 4h group and not in a formal club. please don't forget this.

There's zero proof that he stepped over the line, just his concern he may have. adding the weight of the motor to the rocket weight ready to fly without it showed he was not over the limit. People just went off the deep end because he wasn't exactly certain.

it's all good, no one got hurt, no property was damaged, the best proof is that he was still in mid power weight. everyone chill.

i wish i could close the thread to keep people from spinning out.

 

[OzHybrid]

The OP is a 4h person flying in a 4h group and not in a formal club. please don't forget this.

There's zero proof that he stepped over the line, just his concern he may have. adding the weight of the motor to the rocket weight ready to fly without it showed he was not over the limit. People just went off the deep end because he wasn't exactly certain.

it's all good, no one got hurt, no property was damaged, the best proof is that he was still in mid power weight. everyone chill.

i wish i could close the thread to keep people from spinning out.

I thought everyone was chill. We all took a lot of time and patience to explain the rules, where they come from, how they changed historically.

The OP was a bit upset having discovered there were multiple sets of rules that had to all be read together. Thats why it's invaluable to join a club.
So whats a 4h? And why would NFPA1122/1127 not apply?

 

[OverTheTop]

https://en.wikipedia.org/wiki/4-H
A bit like Young Farmers is here on Oz. I was a member back in '83-'89.

 

[Titan II]

So whats a 4h?

Ever hear of Google?

 

[OzHybrid]

Ever hear of Google?

Sure but you forgot to quote the 2nd part and my objective was to clarify understanding in this thread. Rather than say google the relevant standards and figure out how they all fit together I explained them to assist with understanding how they work together. Just sayin....

 

[thecapotc]

Nothing seemed out of control to me.

I still think there might be some room for increased awareness for the community of the lines but then again if you follow the more normal progression from Estes kits to small LOC/Madcow/etc and then big kits maybe it’s clearer. Or if you don’t lone wolf it in the middle of nowhere.

I took a step I normally would not have to raise money so the club could provide everything for the members. It’s now a tradition we will carry on, albeit with rockets and motors clear below L1.

Al least until I listen to the voices telling me to make that 4” Optima / Phoenix and get my L1. When those voices win I’ll make sure to stop in and see the rocket poli… RSO on a launch day before the big launch and then 4H in the middle of nowhere will never be the same

 

[OzHybrid]

Nothing seemed out of control to me.

I still think there might be some room for increased awareness for the community of the lines but then again if you follow the more normal progression from Estes kits to small LOC/Madcow/etc and then big kits maybe it’s clearer. Or if you don’t lone wolf it in the middle of nowhere.

I took a step I normally would not have to raise money so the club could provide everything for the members. It’s now a tradition we will carry on, albeit with rockets and motors clear below L1.

Al least until I listen to the voices telling me to make that 4” Optima / Phoenix and get my L1. When those voices win I’ll make sure to stop in and see the rocket poli… RSO on a launch day before the big launch and then 4H in the middle of nowhere will never be the same

If you have access to a site in the middle of nowhere, I'm sure you'd find plenty of folks on this site who would be prepared to assist you submitting a high altitude waiver..... . You'll make new friends.

 

[86mustang408w]

This is a good point, but your safe. I do weigh all of mine, but recently went to a launch and I'm sure some orhers had some that were right on that line. I'm going for my Level One Certification soon, have you thought about that?

 

[86mustang408w]

Nothing seemed out of control to me.

I still think there might be some room for increased awareness for the community of the lines but then again if you follow the more normal progression from Estes kits to small LOC/Madcow/etc and then big kits maybe it’s clearer. Or if you don’t lone wolf it in the middle of nowhere.

I took a step I normally would not have to raise money so the club could provide everything for the members. It’s now a tradition we will carry on, albeit with rockets and motors clear below L1.

Al least until I listen to the voices telling me to make that 4” Optima / Phoenix and get my L1. When those voices win I’ll make sure to stop in and see the rocket poli… RSO on a launch day before the big launch and then 4H in the middle of nowhere will never be the same

I've been aware of the rules but haven't come close yet to breaking them but this was a good point to bring up. I'm right on that line now to high power. Going for my L1 soon, so that will be a worry of the past but I will definitely keep this in mind.

 

[OzHybrid]

Based on the discussion over here ( https://www.rocketryforum.com/threads/do-you-consider-mpr-a-pre-requisite-for-hpr.160426/ ) I went back and did some checking on just how close did my 4H club come to the HPR line and did I accidentally lead them over it.

The club members didn't do any building without supervision, and all rockets were assembled with either JB weld or BSI 15 minute epoxy. I wasn't an experienced HPR builder, but I am a Mech. Engineer who's worked in manufacturing on equipment for 20 years, what I would consider handy (grew up in the country fixing all sorts of things, working on cars, etc.) and have used epoxy for all sorts of things.

Our goal was low and slow display launches with one launch per model (a 4H sponsor received the rocket for permanent display after the flights).

My question, and where I may have led the group into HPR accidentally, is on NAR Level 1 and the requirement for rocket weight.
Per NAR's website a Level 1 certification is required if a person wants to "3. Launch rockets that weight more than 53 ounces".
Does this mean empty or loaded for flight?

What was built and launched:

LOC IV on a G74
Based on what I can find online this would have weighed 35.1 oz plus paint and dog barf. I don't think we hit 53 oz.

LOC T-LOC 4" on a F26
Based on what I can find online this would have weighed 39.6 oz plus paint and dog barf. I don't think we hit 53 oz.

Apogee Zephyr on a G78
Based on what I can find online this would have weighed 48.4 oz plus paint and dog barf. I think we probably hit 53 oz with this one.

We were launching away from the spectators on a closed site, but I think we may have pushed through the rules a little if the weight limit is based on a fully flight ready rocket.

Either way if the club continues this fundraiser I'll be keeping a closer eye on the weight requirement moving forward.

So you've had a chance to go through the replies. From them and your experience of running a group, what do you feel could have assisted you to have the information that was missing? How could another group do things better?

 

[thecapotc]

So you've had a chance to go through the replies. From them and your experience of running a group, what do you feel could have assisted you to have the information that was missing? How could another group do things better?

I've been turning this over in my head and honestly, I can't think of a way to reach somebody who follows the path I did or a similar path where you just wander into it. Even in my path one small change to any of the steps could have led to a different outcome (find best rocket blog on the net -> get back into rocketry -> start a 4H club -> eschew traditional meat stick/candy bar fundraisers for something way cooler -> best rocket blog stops -> wander into TRF -> wander into MPR -> wander into the LPR to MPR to HPR thread).

The participation trophy millennial in me wants this to be somebody else's problem ... but the rest of me that grew up hating participation trophies says suck it up and do it right.

It would be easy to say "Hey Mr. Kit manufacturer, if that kit is over XXXX grams un-assembled you have to put a warning on it" but that's just another hurdle for a manufacturer, and unless it's a note in the build instructions that note is going to be tossed in the trash once the kit gets opened.

The other option would be to require an L1 certification to order kits and motors that *could* get you there, but that's just another hurdle for retailers with unintended consequences (I could see a world with this requirement where MPR basically ceases to exist and everything is either a model rocket by a large margin or a high powered rocket you need an L1 for).

The only thing I can think is that maybe a slicked-up marketing version of the chart from Post #14 could be displayed on websites for rocketry vendors but then again how many people get to erockets or apogee and order a 4" kit randomly?

 

[smstachwick]

I've been turning this over in my head and honestly, I can't think of a way to reach somebody who follows the path I did or a similar path where you just wander into it. Even in my path one small change to any of the steps could have led to a different outcome (find best rocket blog on the net -> get back into rocketry -> start a 4H club -> eschew traditional meat stick/candy bar fundraisers for something way cooler -> best rocket blog stops -> wander into TRF -> wander into MPR -> wander into the LPR to MPR to HPR thread).

The participation trophy millennial in me wants this to be somebody else's problem ... but the rest of me that grew up hating participation trophies says suck it up and do it right.

It would be easy to say "Hey Mr. Kit manufacturer, if that kit is over XXXX grams un-assembled you have to put a warning on it" but that's just another hurdle for a manufacturer, and unless it's a note in the build instructions that note is going to be tossed in the trash once the kit gets opened.

The other option would be to require an L1 certification to order kits and motors that *could* get you there, but that's just another hurdle for retailers with unintended consequences (I could see a world with this requirement where MPR basically ceases to exist and everything is either a model rocket by a large margin or a high powered rocket you need an L1 for).

The only thing I can think is that maybe a slicked-up marketing version of the chart from Post #14 could be displayed on websites for rocketry vendors but then again how many people get to erockets or apogee and order a 4" kit randomly?

Many manufacturers enclose the NAR Safety Code in their products, which specifically lists the liftoff mass limitation. NAR members are bound by it (for insurance and membership purposes at least) and RSOs should be enforcing it at club launches.

I believe my Astrobee D kit included it but I’ll have to check.

I think the assumption is that anybody flying with experience from Estes-type stuff will already know it by the time they buy the kit and anybody buying the kit as their first will be depending on the instructions for successful flight. These assumptions are correct often enough that violations aren’t super common and the Consumer Product Safety Commission has felt no need to act further than requiring G motor buyers be 18.

 

[thecapotc]

Many manufacturers enclose the NAR Safety Code in their products, which specifically lists the liftoff mass limitation. NAR members are bound by it (for insurance and membership purposes at least) and RSOs should be enforcing it at club launches.

I believe my Astrobee D kit included it but I’ll have to check.

I think the assumption is that anybody flying with experience from Estes-type stuff will already know it by the time they buy the kit and anybody buying the kit as their first will be depending on the instructions for successful flight. These assumptions are correct often enough that violations aren’t super common and the Consumer Product Safety Commission has felt no need to act further than requiring G motor buyers be 18.

Yep overlooking that little flyer was one of the steps to get here. My brain has been set to using inches and pounds as minimum measurements for the last decade of work so I read 1500 grams and went 'Oh that's a lot, I'm not going to make a rocket that big' and promptly forgot that its not even 3.5 lbs.

 

[smstachwick]

Yep overlooking that little flyer was one of the steps to get here. My brain has been set to using inches and pounds as minimum measurements for the last decade of work so I read 1500 grams and went 'Oh that's a lot, I'm not going to make a rocket that big' and promptly forgot that its not even 3.5 lbs.

In the printing of the Safety Code that I familiarized myself with in Stine’s Handbook of Model Rocketry, the Imperial units came first and metric were in parentheses. Did yours do something like this or was it purely metric?

Also: (thread)
Americans will use anything but the metric system

 

[thecapotc]

In the printing of the Safety Code that I familiarized myself with in Stine’s Handbook of Model Rocketry, the Imperial units came first and metric were in parentheses. Did yours do something like this or was it purely metric?

Also: (thread)
Americans will use anything but the metric system

I'd have to go check but I'm pretty sure it's just metric on the one I took a look at.

 

[rcktnut]

Many manufacturers enclose the NAR Safety Code in their products, which specifically lists the liftoff mass limitation. NAR members are bound by it (for insurance and membership purposes at least) and RSOs should be enforcing it at club launches.

I believe my Astrobee D kit included it but I’ll have to check.

I think the assumption is that anybody flying with experience from Estes-type stuff will already know it by the time they buy the kit and anybody buying the kit as their first will be depending on the instructions for successful flight. These assumptions are correct often enough that violations aren’t super common and the Consumer Product Safety Commission has felt no need to act further than requiring G motor buyers be 18.

I don't know about the safety codes but these came with these 2 kits below.: I may have read them maybe not. When I went with my 2 sons and bought my Aerotech Initiator starter set in 1997 and got permission to use a 40 acre and 60 acre field to fly in I was in violation of the safety codes from day one as far as weight goes. I wasn't a member of the NAR yet. Anything at that time over 16oz. had to be reported. Eventually a few friends and I flew there until 2009 and then we immediately got into HPR and had a waiver there.
Here is what I found out as far as weight restriction goes through out the years:

1963-1987: 16oz. limit
1987-1994: 53 oz. limit -Rockets getting bigger heavier!!! Tripoli is here now too
1994-2009: 16- 53 oz. limit but anything over 16 oz. needed to notify ATC. 16-53oz. rockets determined by FAA to be large model rockets.
2009- present: 53 oz. limit- FAA finally figures out that no planes have been hit in this time period,(1994-2009) and nobody has been contacting ATC anyway.

 

[rcktnut]

With the proposals to change the classifications in 2007 one would think that the weight restriction could have been dropped in favor of classifying the rockets by LPR, MPR as class1 and HPR as class 2. These proposals were being discussed while APCP was still considered an explosive and not knowing the outcome of the lawsuit. Things would have been much clearer by eliminating the few HPR(H) motors allowed to fly under the current class 1 without a waiver. Flying the few HPR motors allowed was the only gain. Still need to fly under HPR codes. Flying a MPR motor in any weight rocket that can be done safely should not need a 50% bigger field to fly in, L1 certification or an FAA waiver.
Anyone in the know please comment!!

From the FAA website:

Amateur Rocket Definitions

We proposed two new classes of amateur rockets. We defined Class 1 as an amateur rocket using less than 125 grams (4.4 ounces) of slow-burning propellant and weighing no more than 454 grams (16 ounces) including the propellant. We defined Class 2 as an amateur rocket using less than 125 grams (4.4 ounces) of slow-burning propellant and weighing no more than 1,500 grams (53 ounces) including propellant.



The NAR, ROC, and 13 individual commenters noted that the only difference between Class 1 and Class 2 is weight. The NAR conducted computer flight simulations of these two classes of amateur rockets to demonstrate the “heavier models have far less velocity and altitude potential.” The NAR's flight experience with rockets meeting the specifications of both classes indicates that both types can be flown using the operating limitations proposed for Class 1. The NAR, as well as the other commenters on this section, recommended combining Class 1 and Class 2 into a single classification—Class 1. The other classes would be renumbered. Therefore, requirements specified in the NPRM for Class 3 and Class 4 now apply to Class 2.


The FAA created the two classes, model rocket and large model rocket, in 1994. Since that time amateur rocket hobbyists have established a history of safe operation for large model rockets. We have analyzed the performance of proposed large model rockets, in light of NAR's suggestion, and found they can cause more significant damage to persons or property than model rockets. However, neither model rockets nor large model rockets can affect air traffic if operated in accordance with this regulation. Since local ordinances cover hazards due to the reckless use of model and large model rockets on ground-based property and persons, the FAA agrees that combining these two classes is appropriate. Therefore, the FAA combines the proposed Class 1—Model Rocket and Class 2—Large Model Rocket into a single Class 1—Model Rocket. We have decided the operating limitations contained in § 101.24 of the NPRM are not necessary for the combined Class 1 Model Rockets, and, therefore, proposed § 101.24 is removed.

 

[SolarYellow]

Full document in PDF here:
https://www.govinfo.gov/content/pkg/FR-2008-12-04/pdf/E8-28703.pdf

 

[Tractionengines]

Why are we posting SO MUCH about what WERE the rules? All these history dissertations, scanned flyers, PDF files, descriptions, etc. etc. etc. are just going to muddy the water even more for someone CURRENTLY getting into (or back into) the hobby.

If any of the above get referenced out of the context if this history lesson, they are NOT CURRENT, or VALID, REFERENCES. But that caveat can easily be lost.

It would be great if we could just leave it at a summary of what the CURRENT limits ARE, and leave it at that. This way someone who is getting ready to fly a rocket NOW, would have a clear YES/NO to work from. [ They don't need to know that 15 years ago the rules were different.] The color coded table (that shows up in all these types of threads), is a great reference.

 

[Titan II]

This is the kind of absolute foolishness that makes many go Lone Wolf.

 

[smstachwick]

I don’t see much value in adjusting the current rule set for edge cases. Know the Code and your units, and if you’re unsure, weigh your model and check the specs of the motor(s) you plan to use.

As stated before, you’ll occasionally see people toe over the line unknowingly but the limits are low enough that it takes special effort for, say, a rocket running a 2x G80T cluster configuration and busting the weight limit to pose significantly more hazard to aircraft than a similar design that is barely within limits. Other safety rules and cross checks, if properly followed with due diligence, can hopefully prevent a serious accident long enough for the error to be caught or for the flights on that particular rocket to stop for some other reason (recovery damage, loss of rocket, exiting hobby, etc.).

Still, these rules are there for safety. Not for ignoring, not for the opposite extreme of kicking people off the range over inadvertent infractions, but for safety. Know your rocket and if you make a mistake, just fix it or get certified (or both) before further flight. No need for a lot of hoopla.