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View Full Version : Anyone done their Level 2 cert with a 3" rocket?



RoyAtl
10th March 2009, 07:21 PM
I have a LOC Caliber-ISP that has never flown, and was thinking about maybe using it for my level 2 certification. Anyone used a 3" rocket for such? My only problem is that the field I normally fly at has lowered its allowable altitude to below the Caliber's potential apogee on a J350.

I have a bigger rocket, but I don't really want to use it for a J-powered flight.

FROB
10th March 2009, 07:34 PM
I have a LOC Caliber-ISP that has never flown, and was thinking about maybe using it for my level 2 certification. Anyone used a 3" rocket for such? My only problem is that the field I normally fly at has lowered its allowable altitude to below the Caliber's potential apogee on a J350.

I have a bigger rocket, but I don't really want to use it for a J-powered flight.

Does the motor have to be a J-350? I'd fly it on an H & I motor first, use the altimeter data to calibrate the sim's in rocksim, and run some sims with different J motors and find one that keeps you safely below the waiver. otherwise, add some ballast in there like a bottle of water, and sim it some more.

Rocketjunkie
10th March 2009, 07:36 PM
My only problem is that the field I normally fly at has lowered its allowable altitude to below the Caliber's potential apogee on a J350.

I have a bigger rocket, but I don't really want to use it for a J-powered flight.The Caliber won't come close to the waiver at Orangeburg. What's the waiver at Lilly? When I was there years ago, it was 10K.

m85476585
10th March 2009, 07:39 PM
I did my Level 2 on a 3" rocket. It weighed 6lbs, though, so it didn't go too high (maybe 3-4000 feet).

hognutz63
10th March 2009, 07:50 PM
Level 2 last fall
3" WildmanDD
9.5 lbs w/o motor
AT J570
3498'

Last weekend
Loki L1400
13,263'

stickershock23
10th March 2009, 11:43 PM
I have a 3" duel deploy that Weighs in at just under 10 lbs loaded, It consistently hits 4000 feet.

Actually I HAD a 3" rocket... now I have a fincan and motor mount... the rest is in the lakebed floor. way in LOL

ben_ullman
11th March 2009, 12:22 AM
My dad did his L2 on a 3" LOC Caliper. 3800' on a J365 skidmark

Ben

troj
11th March 2009, 12:55 AM
My Level 2 was on a 4" airframe, but I've seen (and signed off on) plenty of L2 certs on 3" rockets.

If you're concerned about altitude, consider adding some removable ballast, to help keep the altitude down. Just run sims to make sure you're not pushing it closer to optimal mass (doesn't sound like you are).

-Kevin

rwt
11th March 2009, 03:28 AM
I flew my level 2 with a stretched LOC Forte, and a J350. The MAWD reported 5243'. It was a fun flight to watch!

monkey_bolt
11th March 2009, 10:05 AM
Hi I passed my L2 using a LOC Caliber in Dec 08. I converted it to DD using a LOC E-bay and flew it on a CTI J285 classic. These motors are great, especially for a cert flight and only a 1% J. Simply unwrap screw into casing and launch. I left the motor ejection in as backup (just in case). Total lift off was just over 5 1/2 lbs and apogee was at 4092, sim was 4800 max so not bad.

I didn't bother fitting a drouge as this is a fairly light rocket, main deployed at 700' which was a little low and would probably set it to 1000ft next time. If you concentrate you can just about see the rocket at this altitue. If you want any pictures of my build just ask.

Go for it!!

Mike

JDcluster
11th March 2009, 11:03 AM
I flew my glassed Caliber ISP on a big I or small or J motor & got 4,300 ft
A Caliber ISP / Forte is basically the same rocket but with a different motor mounts. It weighs in around 6.2lbs fully loaded with motor.


Forgot to mention; I added a Aero-Pak tail cone/motor adapter ( it's removable ) for 38mm motors.


JD

Viperfixr
11th March 2009, 11:45 AM
See http://www.rocketryplanet.com/forums/showthread.php?t=3239

bobkrech
11th March 2009, 03:24 PM
I have a LOC Caliber-ISP that has never flown, and was thinking about maybe using it for my level 2 certification. Anyone used a 3" rocket for such? My only problem is that the field I normally fly at has lowered its allowable altitude to below the Caliber's potential apogee on a J350.

I have a bigger rocket, but I don't really want to use it for a J-powered flight.
It's your choice, however the LOC Caliber-ISP will exceed 4,000' on a J-350 so if your waiver is lower...

I personally think that the HyperLOC 300, which is a very similar rocket, is a better choice if you want a 3" rocket as it includes an electronics bay and drogue for a dual deployment to greatly reduce the recovery walk.

Bob

pyrovette20
12th March 2009, 02:10 PM
I have a bigger rocket, but I don't really want to use it for a J-powered flight.

How big is this rocket and why not fly it on a J motor if you are worried about altitude.

skip_dye
12th March 2009, 05:20 PM
I did mine with a 2.6 inch airframe. Flew it on a AT J420R to just shy of 4800 ft.

Alan

RoyAtl
12th March 2009, 07:04 PM
ok, all good suggestions.

Let me clarify my situation further.

I did my NAR cert in March 1991 (in fact I was the first HPR consumer certified by NAR), then got confirmed in Tripoli in June of that year. Bought a Magnum and a 54mm casing from Ron Schultz at Danville in 1991, but never used them and sold them in '97. Basically, I got HPR out of my system early.

I have three L2-capable HP rockets, all built in 1991. The Caliber (never flown), an EZI-65 (flown about 30 times), and the MegaAlpha (9 flights), which is essentially a stretched Minie-Magg. All were built before the advent of dual-deploy.

I want to do a cheap'n'dirty L2; motor deployment only. Since my hardware is 38mm, J350 seems like the safe choice (I'll have to beg a longer casing). Don't want to build a new rocket, don't want to convert any of the existing ones to dual-deploy. Lilly, GA is the field of preference, and Leonard has just lowered the max altitude there to 5000'.

I built the MegaAlpha to fly on up to K motors, but I've only flown it on I211, and see no reason to use anything else. Plus, it has sentimental value, and I've already almost lost it once on an I211, and reefing the chute is problematic because it already comes down pretty hard on a 50" chute and the hard pointy Alpha fins.

The EZI-65 should be ok; its payload compartment has been stretched, so ballast should be easy, but I wonder about the thin fins on a J350 boost (it *has* flown under H238 and I211)

So the Caliber is my current choice, I'll just have to use some ballast.

Ideally, I'd just fly the MegaAlpha, go to about 3000' and be done with it.
Maybe if the wind is right that's what I'll go with anyway.

pcotcher
12th March 2009, 08:39 PM
When did it get lowered? Here I was thinking that our home field was a 10K field. Guess we're going to have to get pushing on those other potential locations.

snaquin
13th March 2009, 01:13 AM
If the Caliber is your current choice I'd use it, but I don't think I'd add any ballast without checking it with a simulation program.

Depending on the amount of ballast you add it may put you closer to an optimum mass and actually obtain a greater altitude. It could increase your velocity at deployment so since you are using motor ejection you could risk a zipper on your L2 flight.

A quick run with a J350 using the Caliber ISP file posted on EMRR shows just above or just below the 5,000' waiver depending on using a ten or fourteen second delay but your actual altitude will probably be less than what RockSim estimates in the real world and of course the weight reflected in this file isn't your true Caliber's weight either.

Personally I'd fly it bone stock, if the club would allow it and back my request up with some data to show them it wouldn't break the waiver.

.

Obi-Wan
13th March 2009, 01:22 AM
Got 5250'. held together.

bobkrech
13th March 2009, 02:58 AM
An EZI-65 with a launch weight of 5.5 pounds with a J350-10 should stay below 3000' and under 500 mph and descend at ~16 fps with a 6' chute. The stock fins shouldn't be a problem at that velocity.

Bob

RoyAtl
13th March 2009, 04:43 AM
An I-ROC with a launch weight of 5.5 pounds with a J350-10 should stay below 3000' and under 500 mph and descend at ~16 fps with a 6' chute. The stock fins shouldn't be a problem at that velocity.

Bob

If I had an I-ROC, I'd be all set, and wouldn't have asked the question.

Instead, I have the MegaAlpha (roughly same size as I-ROC) and two smaller rockets.

http://www.roygreen.com/images/me_and_vern.jpg

So really, I just need to get over it and fly the MegaAlpha as my L2, and just pick my winds.

RoyAtl
13th March 2009, 05:24 AM
When did it get lowered? Here I was thinking that our home field was a 10K field. Guess we're going to have to get pushing on those other potential locations.

A month ago, due to insurance concerns. Even though there are fields surrounding the sod farm, and we recover from those fields, they are not part of the sod farm property, and therefore aren't covered by the insurance. Therefore, taking the minimum distances from field size, he came up with 5000' max.

Rocketjunkie
13th March 2009, 05:53 AM
The EZI-65 should be ok; its payload compartment has been stretched, so ballast should be easy, but I wonder about the thin fins on a J350 boost (it *has* flown under H238 and I211).An EZI is marginal. Unless the fins are perfectly symmetrical (airfoiling, rounding), they are likely to fail. An I211 always is ok, I284 usually, and a J350 about 1/2 the time (assuming no reinforcement, glassing or replacing thw fins with G10). I once built a rocket just like an EZI but with clipped delta fins the same span, chord, area, and material and it survived a J415 and K160.

Come to Orangeburg. It's not *that* much farther than Lilly.

bobkrech
13th March 2009, 01:39 PM
If I had an I-ROC, I'd be all set, and wouldn't have asked the question.

Instead, I have the MegaAlpha (roughly same size as I-ROC) and two smaller rockets.

http://www.roygreen.com/images/me_and_vern.jpg

So really, I just need to get over it and fly the MegaAlpha as my L2, and just pick my winds.
Roy

I checked out both and I posted the calculations for the EZI-65, not the I-ROC, but mislabeled it. A 5.5 pound EZI-65 or other 4" rocket with a J350-10 will hit 3000' and with an apogee deploy is too high at our field for an assured in-field recovery, so we actually recommend the I-ROC or any 5.5" to 7.5" kit for apogee deployment L2 attempts. A 5.5 pound I-ROC on a J350-7 will hit 2000'.

Bob