Mini BBX on a G64?

[Zippy]

Has anyone flown a Mini BBX on a G64? I've just finished one and I'm not sure if a G64 has enough power for a straight up flight. I have a launch rod with 57" of usable length and RockSim says it leaves the rod at just over 25 mph. Thats a little slower than I like but I'm not sure it's really right so thats why I'm asking if anyone has actually done it.

I only want to use the G64 if the altimeter I ordered and some DaveyFire N28b's don't get here in time for when I plan it's maiden flight. Thats becouse I'll use a G75J with dual deploy then. It should go about 1600' on the G75J and thats just a little too high I think for a possible residential area (or swamp) recovery using motor based ejection only on the field I'll probably be launching from.

Anyone with G experience on the BBX please chime in! And if you can please tell me what length rod you used.

Oh yeah, just to keep the pic police happy here it is...

 

[Johnnie]

I have a photo somewhere of a mini BBX that a gentleman flew on a G64...Blistering flight to about 75 ft. when the rear closure failed, sending the BBX cartwheeling with the tail feathers in flames...

Not what you wanted to hear I guess, but unless you built the BBX really heavy, should do good...at least on a G64-4 What is the final weight of the BBX, and I'll try to sim the G64 for ya.

Love that "C"-slot motor

 

[Zippy]

I wish I could give you the real weighed in weight as it is. I can only tell you PML claims 39 ozs. I believe this is what they use in the RockSim file as well. I can't actually weigh anything heavier than my diet scale's 16 ozs. and the sustainer portion max's that out easy without the cargo section attached. I've also added kevlar 'chute pads and some quick links and some small nuts and bolts for the hardware that is the aviation bay. I'm only using the trial version of RockSim but nevertheless I'm a bit skeptical about rod speeds after launching slightly smaller rockets on G64's, they tended to hurl off the rod no problem. But the Mini BBX IS heavier so I prefer to be cautious.

 

[Stones]

Zippy...
I sim it out at 40oz. w/o motor and here's what it comes up with using a G64-7...

Launch guide data:
Launch guide length: 57.000 In.
Velocity at launch guide departure: 37.566 ft / s
The launch guide was cleared at : 0.339 Seconds
User specified minimum velocity for stable flight: 43.999 ft / s
Minimum velocity for stable flight reached at: 79.001 In.

The 43.999 ft/s is the default speed of RSim.

 

[Juerg]

Hi Zippy

No problem!
One of our club members, Tommy Biro, flies a MiniBBX <u>with</u> pencam on a G64!
https://www.argoshpr.ch/Images/ALRS3_20021027_Haux/PA260981.JPG
https://www.argoshpr.ch/Images/ALRS3_20021027_Haux/PA260982.JPG
and here the Pencam Movie (8MB!)
https://www.argoshpr.ch/images/ALRS3_20021027_Biro/MiniBBXALRS.avi

I wouldn't use this motor in windy conditions, but on a calm day it is nice.

Juerg

 

[Zippy]

Stones,

That looks good, or at least better than I got on the demo. Maybe the formula changed in different versions of RockSim. It seems to also want a higher minimum speed but I think It will probably be allright if as...

Juerg,
said and I only launch in low wind. In Florida it's like wait, wait ,wait then count real quick and press the button real fast before the breeze blows again. Thanks for that video tooo, I think I'm gonna save that.

 

[eugenefl]

Zippy,

If you're interested in flying it at the next local Tampa meet and want to use my rail, you are more than welcome to it. There's a good 5.5ft of usable rail there instead of a rod. If you need a set of buttons, drop me a line. I can toss a set in the mail. I have plenty. Besides, I want to see that rocket fly! Any thoughts on going with a G80?

 

[Zippy]

Eugene,

Yeah I do want to fly it then. I don't think I'll be able to get a G80 in time and I like using the reloadable hardware anyway. The rail buttons are a good idea, but then I'll want a rail too and I just don't need to spend more right now. Thanks for the offer though. I'm still holding out to be able to use dual deploy and the G75 hopefully as well

 

[eugenefl]

Originally posted by ZippyOgiveHead
Eugene,

Yeah I do want to fly it then. I don't think I'll be able to get a G80 in time and I like using the reloadable hardware anyway. The rail buttons are a good idea, but then I'll want a rail too and I just don't need to spend more right now. Thanks for the offer though. I'm still holding out to be able to use dual deploy and the G75 hopefully as well

I have a few G80s in my box both in -4 and -7 delays. My largest bird that takes them is currently out of commission due to a prang last meet. I'm sure we can work out some kind of trade. (That is if you're still interested in the G80 over the G75.) I'd prefer that you fly your rocket comfortably than risk damaging something that nice. I am in need of a G40-7 for my Bullpup. I'm not quite ready to put a G80 in it at the HWY56 field. Flies sweet on a G40 though!

Wait, I just did a quick search on the web for a G75 and realized it's a BlackJack motor! Cool! Ok, you're gonna have to twist my arm for the G80 now! LOL!

 

[Zippy]

I'm comfortable using a G75, should be more than enough power to get it off the rod in rapid fashion. The G64 did have me slightly concerned but I got my altimeter and DaveyFire's so now I'll use the G75 and not worry about getting to near 1600'. It's in the 29-180 casing that I haven't used yet so I got that "new toy" factor to satisfy as well. I don't have any G40's but I have G64-4's and F40-4's (29/40-120) that I could trade for something since the 4 second delays are a bit short for any rocket I currently own. I'll bring a couple along next week just in case, hopefully the weather will be better too!