Aerotech G-Force experiences



You are wrong. if launches are being run that way where you are, be they NAR or TRA, they too are wrong.
--
Bob Kaplow NAR # 18L >>> To reply, there's no internet on Mars (yet)! <<<
Kaplow Klips & Baffle: http://nira-rocketry.org/Document/MayJun00.pdf
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Bob Kaplow wrote:

Bob, Are you telling me: "at your launches, someone wants to launch a a AT Baracuda ona AT G80-T, a rocket that weighs in at more than 1500g loaded, (at least mine soes), the individual can only launch if the individual is HPR cert level 1 or better"??? Say it isn't so Bob.....
Fred
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Reading the NAR Model rocketry safety codes: http://nar.org/NARmrsc.html
Size. My model rocket will not weigh more than 1,500 grams (53 ounces) at liftoff and will not contain more than 125 grams (4.4 ounces) of propellant or 320 N-sec (71.9 pound-seconds) of total impulse. If my model rocket weighs more than one pound (453 grams) at liftoff or has more than four ounces (113 grams) of propellant, I will check and comply with Federal Aviation Administration regulations before flying.
To me that reads that any rocket that weighs more than 1500g (53oz) does not fall under the model rocketry safety guidelines. The only other guideline for NAR is the HPR guidelines. Those guidelines are: http://nar.org/NARhpsc.html
# Weight and Power Limits. My rocket will weigh no more than the motor manufacturer's recommended maximum liftoff weight for the motors used, or I will use motors recommended by the manufacturer of the rocket kit. My high power rocket will be propelled by rocket motors that produce no more than 40,960 Newton-seconds (9,204 pound-seconds) of total impulse.
I don't see a minumum weight or a maximum. Just the maximum that the motor manufacterer recommends.
That covers NAR's guidelines. I can't speak for TRA nor for the FAA (or the BATFE, not that they should really care)
-Aaron
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http://home.flash.net/~samily/stuff/HPR_metric8.pdf
BOOKMARK
PRINT
READ
--
-Fred Shecter
remove zorch two places to reply
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And whom is the source of that PDF, web page please..
Fred Shecter wrote:

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One more thing; FAA has no authority and could care less about HPR certification as this pamphlet seems to imply, especially in the explanation of the fifth line. No mention of certification for rocketry launching is mentioned, anywhere in FAR 101.
Fred W
"W. E. Fred Wallace" wrote:

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Come on. Use your browser. You click on the link, then you delete the last few characters to get to the home page or root directory. http://home.flash.net/~samily/stuff/HPR_metric8.pdf http://home.flash.net/~samily/ takes you to:
http://home.flash.net/~samily/DougsRockets /
Which provides you with the info you seek.
He does not ever say the FAA uses the term "HPR".
He does clearly state the FAA limits for notification for "LMR" (which IS an FAA term) and anything beyond an LMR requires an FAA waiver.
if you think he is incorrect, e-mail him.
-Fred Shecter NAR 20117
--
"""Remove "zorch" from address (2 places) to reply.
http://www.sirius.com /
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Yes yes, I figured out all that browser stuff last night. One of the finest individual rocketry web sites I have ever visited..
I don't dispute the FAA notification and waver requirements, just the certification requirement to launch a G 80 powered 1500g + rocket. "Show me the money", directly and not implied rhetoric.
Fred W
Fred Shecter wrote:

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Aaron wrote:

Your right Aaron, my bad -- 1500 grams or greater is a high power rocket and must be launched as such. I wasn't thinking when I used the Barracuda loaded with a G80, as it only weighs in at slightly over 1lb -- I just checked it. However, no mater the total weight, less than 1500g or greater than, you don't need HPR certification to launch the darn thing on a G80T. Hell, before I was HPR certified, (several years ago), I launched my LOC Mini-Mag on AT G80-4T motors on several occasions; and yes it was at wavered launches, but no one was concerned about my lack of cert level, just a lot of, "listen to that thing roar". It only went about 500' + or -, but it got there with authority.
Fred
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Before my level 1 cert, I walked right up to 3.3lbs (1500g) line, but never crossed it. Now that I have my level 2 cert, I'm in the pre-build stages of a 40+ pound monster. (near 1/2 scale patriot, if anyone cares) that I'll send up on an A/T K1275
If you built a rocket that used 2 A/T G80T motors, you'd still be able to launch it without a cert assuming that the rocket was less than 3.3lbs (1500g) and you had the proper FAA notification. The Aerotech website says that a G80T has 120 N-sec of thrust. 2 of these would put a rocket at 240N-sec, well below the 320N-sec limit. ( http://www.aerotech-rocketry.com/customersite/resource_library/Certification_Documents/NAR/single-use/29mm_mr_su/g80t_nar_cert.pdf ) Sorry for the long link.
I don't see what the big problem is. The Aerotech website for the G-Force says the dry weight of the rocket is 32 oz. You can add 21 oz of motor and payload before you reach the magical 53 oz limit. It falls below the limits for cert. If it will be stable on that motor, launch and enjoy!
-Aaron
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On Wed, 1 Mar 2006, Aaron wrote:

Ours is weighing in at 36.5 ounces. Built with medium CA for most of the rocket, the lugs are expoyied on and not painted (yet anyway).
I really don't know how that extra 4.5 ounces came from.
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I have found that almost all kit makers underquote the dry weight of their rockets. I don't know why, but its almost always true. I think it's an "ideal" weight, but I have yet to build one that matched the specified weight.
36.5 oz = 1035g A/T G80T-4 = 105g Rocket + Motor = 1140g
allowable payload = 360g or 12.7 oz
You could send up a full can of coke if you wanted. (I know fl oz !oz....but it would be kinda cool to send up a can of coke anyway)
-Aaron
Helen Rapozo wrote:

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Correct. And they have to use an HPR pad and meet HPR safe distances and we need a waiver and not just notification. Ditto for a Mustang with a G33, or when they were available an F101 (except for the waiver parts on these light rockets).
--
Bob Kaplow NAR # 18L >>> To reply, there's no internet on Mars (yet)! <<<
Kaplow Klips & Baffle: http://nira-rocketry.org/Document/MayJun00.pdf
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I would question the Mustang with a G33. The Aerotech website lists the dry weight of a Mustang as 320g. glue/paint/sloppy build/etc make it 400g. A G33 is certified as 100N-sec of impluse with 72.2g of propellant and weighs 160g. A rocket weighing in at 560g, having a motor that is less than 160N-sec and less than 125g of propellant. No cert is required but a FAA notification would be (1.2lbs for this configuration) An HPR pad would not be required, neither would HPR safety distances. I could find the numbers for the F101, but as they are no longer certified, it doesn't really matter.
All limitations are moot if the RSO/LCO raises those limitations. An RSO can tell you to launch that Quark from a HPR pad if they want and you'll launch it from there or it wont launch at all.
-Aaron
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After re-reading this (type, read, THEN post, I know) the G33 exceeds the 62.5g limit for a single motor. My applogies.
-Aaron
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Aaron wrote:

Yea, but a G80T does not exceed 62.5g, so why the need for HPR certification to launch the motor in a 1500g + rocket? All I can find indicates launch it as a HPR; nothing about being certified to fly HPR. Maybe the understood intent is that you would use an H or above HPR motor to launch. This whole subject is starting to get anal. All I know for sure; I launched my Loc Mini-Mag on A/T G804T before I was HPR certified and no one had an issue with it. And by the way, it was at a NAR launch right in good old Middletowm MD..
Fred
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W. E. Fred Wallace wrote:

So, now we know...
"Who flew the G???" <G>
David Erbas-White
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Any rocket over 1500g is an HPR rocket. NFPA 1127 requires HPR certification to fly an HPR rocket.
--
Bob Kaplow NAR # 18L >>> To reply, there's no internet on Mars (yet)! <<<
Kaplow Klips & Baffle: http://nira-rocketry.org/Document/MayJun00.pdf
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Bob Kaplow wrote:

Well Bob, I guess I'll concede your literal interpretation you presented, regardless of what has been my experience and that of a few others.. (:-)
Found any new and interesting Fly-Cutters lately??
Fred, I not anal!!!
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Actually, this used to be a bigger issue. MR had its defined limits, and HPR had its defined start. All these wierd cases, like a 1501g rocket with a G80, a cluster of 6 D12s, or any rocket with an F101 or G33 were in a limbo zone that was neither MR nor HPR. One of the few times I managed to convince the NFPA folks that their regs were flawed was this case, and all the gray areas were defined as being HPR.
--
Bob Kaplow NAR # 18L >>> To reply, there's no internet on Mars (yet)! <<<
Kaplow Klips & Baffle: http://nira-rocketry.org/Document/MayJun00.pdf
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