Green Jello's Level 1 Build - Wildman Jr. Kit - "Certify With Us" program

[Green Jello]

Thanks Wayco. Maybe you, Troj or FDog can help me out by looking things over with your expert eyes before I light this candle. I'd really appreciate it and it might reduce some of my pucker factor.

 

[Green Jello]

Does this look right? I've gone over all the weights and it's about as close as I can get it. Stability is 4.87 cal. Is that over stable?

 

[COrocket]

Does this look right? I've gone over all the weights and it's about as close as I can get it. Stability is 4.87 cal. Is that over stable?

Yes, that is fairly over stable. You may have some weathercocking if the winds are strong at launch. Most people look for 1-2 calibers. Is that your actual CG or computer generated? You could assemble the rocket and motor exactly the way it would launch to double check. Remember as the motor burns and you loose weight in the aft section, the rocket will become even more stable.

 

[Green Jello]

Crap. I suck at Open Rocket and I always get in trouble with overriding the CP/CG. If I find the CG by hand it's 35.5 inches down from the tip with no motors installed. One of the requirements for the L1 cert is marking the CP/CG on the rocket. How do you get the CP without software?

 

[Wayco]

Thanks Wayco. Maybe you, Troj or FDog can help me out by looking things over with your expert eyes before I light this candle. I'd really appreciate it and it might reduce some of my pucker factor.

Wish I could Dave, but I'm not gonna make it to LDRS. You have two others listed there that are much more experienced than me, they will steer you straight.
I will give you advise based on my DS Jr. though, first flight was to 1995 ft. and it drag deployed the main at apogee because I didn't put shear pins in the N/C. Winds were less than 5 mph and it was a long hike. Last flight at ROCstock with similar conditions but I forgot to turn on my altimeter, apogee came and went and the motor eject split the rocket so it came down drogueless to a relatively soft spot on Lucerne dry lake. Short walk to a perfectly sound rocket, not even a scratch on the paint. These Wildman FG rockets are hard to break. You might be a little big with that chute and even if the winds are calm on the ground, it's gonna take quite a while for that rocket to come down from 4700 ft. If you have even a light wind at altitude, you are in for a hike. My 36" TF standard chute packs up nice in the 54mm body tube, you could probably pack it in a 9" nomex pad, might be a better choice for your cert flight. Even smaller would work, but I figure that your pretty new paint job has you a little concerned..... Pretty sure my Jr. is heavier than your Wildman is, it weighs in at 4 lbs. 7.6 oz.

 

[Wayco]

Crap. I suck at Open Rocket and I always get in trouble with overriding the CP/CG. If I find the CG by hand it's 35.5 inches down from the tip with no motors installed. One of the requirements for the L1 cert is marking the CP/CG on the rocket. How do you get the CP without software?

Barrowman equations:
https://my.execpc.com/~culp/rockets/Barrowman.html

Good luck with that....

 

[COrocket]

Well the CP is fine at 46.8. Your computer generated CP is accurate as long as your exterior dimensions are accurate. That you don't have to override, and a printout should be fine to "prove" stability pre-flight. Or you can use the barrowman equations and do it by hand to double check. Take your assembled rocket and balance it on your finger/hand. That point is the CG. Since it is a pretty easy measurement there is no reason to calculate it. Then put the motor in and repeat. The 1-2 calibers is in the flight ready configuration.

 

[JRL303]

Light the candle! Can you over-think this thing anymore?!

 

[cbrarick]

From RockSim CP 46.7395 CG 32.1308 with no motors loaded. Margin 6.41.....
All of the Wildman kits (mini, Jr, standard, extreme, ultimate) are waaay overstable. I'd be shocked if anyone asked about the CP-CG on this unmodified kit (how many thousands have we seen fly?).

Good luck Mr. Jello!

 

[troj]

Thanks Wayco. Maybe you, Troj or FDog can help me out by looking things over with your expert eyes before I light this candle. I'd really appreciate it and it might reduce some of my pucker factor.

Be more than happy to. I can even go one step further, and sign the cert for you afterwards -- I'm a Prefect.

As far as the CG goes, as Rick suggested, assemble the rocket and balance it. You can do that at the field, if you want. This rocket is small enough that's not hard to do. It gets tougher when you start trying to do it on rockets that weight 40+ pounds...

-Kevin

 

[Green Jello]

From RockSim CP 46.7395 CG 32.1308 with no motors loaded. Margin 6.41.....
All of the Wildman kits (mini, Jr, standard, extreme, ultimate) are waaay overstable. I'd be shocked if anyone asked about the CP-CG on this unmodified kit (how many thousands have we seen fly?).

Good luck Mr. Jello!

That's what I was thinking. I built this thing the standard way and didn't modify the kit much at all. I was just surprised by what Open Rocket said.

 

[cbrarick]

No problems! Just thought the Rocksim would help.

Don't forget to bring LOTS of extra money, because once you fly it....you'll be hooked into a bunch of follow-up flights. I bet it will take you longer to get it back then to prep it out with a new CTI motor.

 

[jmight]

Don't forget to bring LOTS of extra money, because once you fly it....you'll be hooked into a bunch of follow-up flights. I bet it will take you longer to get it back then to prep it out with a new CTI motor.

Absolutely true. By the same token, don't bring too much money, because you will spend it all! When I certified, I took 20 minutes or so to recover it and get the paperwork signed, and within another 5 min, was loaded and pushing the launch button.

 

[Fdog]

Yo Dave!

We'll be home from Bonaire this morning - out to the playa tomorrow. We're planning on setting up camp on the east side, come by and see us!

At your sim altitude, let us know, Janet or I will take you out on the RZR to chase it down.


All the best, James

 

[Green Jello]

Yo Dave!

We'll be home from Bonaire this morning - out to the playa tomorrow. We're planning on setting up camp on the east side, come by and see us!

At your sim altitude, let us know, Janet or I will take you out on the RZR to chase it down.


All the best, James

w00t! Welcome home James. See you out there Friday morning.

 

[Green Jello]

No problems! Just thought the Rocksim would help.

Don't forget to bring LOTS of extra money, because once you fly it....you'll be hooked into a bunch of follow-up flights. I bet it will take you longer to get it back then to prep it out with a new CTI motor.

I plan to fly it a few times and also do my first dual deploy. I own 3 38mm HPR loads already:

I125
I175
H152

 

[Wayco]

Yo Dave!

We'll be home from Bonaire this morning - out to the playa tomorrow. We're planning on setting up camp on the east side, come by and see us!

At your sim altitude, let us know, Janet or I will take you out on the RZR to chase it down.


All the best, James

That should solve the long recovery from 4700 ft.
I sure wish I could be there for this flight, it will be awesome! No way will anyone be able to "reduce your pucker factor" for this, just enjoy it while you can. Did you ever do the "Wildman Oath"? The moon won't be full again until next Monday, July 22nd.

 

[ksm2001]

All the best on your certification.
Sending this message from 7600 ft on top of a mountain in Banff Alberta.

 

[Green Jello]

All the best on your certification.
Sending this message from 7600 ft on top of a mountain in Banff Alberta.

Coooooool! Thanks.

 

[Aksrockets]

Best of luck with the cert! I'll get the best video and pics that I can. Just make sure you talk to me a bit before the flight so I know when yours is flying. See you Friday!

Alex

 

[Spooks]

Good luck on the cert flight, know your gonna have a great time this weekend!!

We couldn't make this trip, but we are going to Airfest this year!!

 

[troj]

Best of luck with the cert! I'll get the best video and pics that I can. Just make sure you talk to me a bit before the flight so I know when yours is flying. See you Friday!

I'll have my camera with me, as well, so I can also get pictures. Just stills -- no video equipment that I'll be bringing.

-Kevin

 

[Green Jello]

In the interest of finding each other over the weekend....

My camp will consist of a little green 2001 Honda CRV under a tarp and PVC car port shelter, next to a large Everest fifth wheel trailer and a maroon Ford F-250 truck.

I am a fairly large fat dude (6' 5" 295 lbs.), 38 years old. I have a short buzz haircut and a rapidly graying goatee caused by these two retards who will be with me:

 

[troj]

I am a fairly large fat dude (6' 5" 295 lbs.), 38 years old. I have a short buzz haircut and a rapidly graying goatee caused by these two retards who will be with me:

View attachment 138185

Minions! You're bringing minions!

I'm easy to find -- find Tripoli HQ, and you'll find my wife. She'll either know where I am, or be annoyed with me.

I look vaguely like this (though the hat is the wrong color -- usually a tan Rockets hat, or a maroon Launch hat)



-Kevin

 

[Green Jello]

I found one in another thread here. It's the only one I have access to at work, but it will do I suppose.

 

[halcro1]

Light the candle! Can you over-think this thing anymore?!

RIGHT.

 

[Green Jello]

It's kinda hard when I'm not at the launch yet. I could light it in the dining room at home where it is if you like.

 

[halcro1]

I think the comment has to do with overthinking of this rather easy build.

 

[Green Jello]

Well sorry if I'm still over thinking this but what size drouge would you use when I go dual deploy on it? I was thinking 18"

 

[Wayco]

Well sorry if I'm still over thinking this but what size drouge would you use when I go dual deploy on it? I was thinking 18"

Drogue? We don't need no stinkin drogue..... You could use the 18" chute for your main though.....:rofl:

Go ahead and overthink this all you want, I don't have any launches until September and am living vicariously through your posts. It's gonna be a difficult time for me while you are out on the playa, I hope you can find some way of posting up your results while you are out there.