1/2A SPORT / SPEED PROP JET
 

Hi all, here is an example of why my .40 speed model has been neglected, I can't keep away from 1/2A projects. I used the upper half outline of a F-16 to help come up with the "jet look". The entire fuselage is just a bunch of 1/8 light balsa panels and formers. The wing is solid 1/4" sheet balsa as well. The stabilators ride on a carbon tube axle and the servos for both ailerons and stabilators will be HS 55s. I have 150 and 300 mah batteries that fit, as well as some park flyer RXs. I'm working on getting an electron RX to cram in there, it gives much better range. The engine is the FORA .049, it puts out 32,000 rpm on 15% fuel and runs an APC 4.2x4 prop. I run it off of a pressure bladder, better fuel feed and lighter to set up than a suction tank. The projected RTF weight is 14 ozs or less. It has 150 sq inch of wing area.

RE: 1/2A SPORT / SPEED PROP JET
 

Combatpigg:

Very sweet looking aircraft!!!!! These little guys are great fun and a lot of bang for the buck. Love the little 1/2-A engines, they turn great rpm and power for their relitive size. Thats one of the reasions I get P.O.-d when I look for a reasonable cost 60 that will scoot. Am told A 20K 60 cant be made to turn 20K without the rear valve and exhaust etc. Then I am out helping the kid (40) with his go-cart, a 2 cycle side exhaust engine much like ours and the thing is turning over 16,800 down the streight. I suspect around 17K and 100 mph+ before l have to hit the brakes in general panic. Its a 125 motocycle engilne! Sorry for the ranting, senior moment. You have outstanding design ability, and must have great eyes to fly these thing. I for one would love to see and hear more about this little scooter! ENJOY

RE: 1/2A SPORT / SPEED PROP JET
 

RMENKE, thanks for the kind words! Those go carts are amazing, aren't they? As low to the ground as they are, 100 mph must feel like 200!

You would be amazed at what you are capable of seeing/flying if the conditions are right. If your eyes are good enough to pass the drivers' license exam, they are good enough to fly high speed 1/2A. Fly a predictable route [no hot doggin'], have a high contrast color sceme [red with white stripes on top works for me] and pick a bright day. Once you feel comfortable, then let the hot dogging commence ;). If you pile one of these up, they are many times more repairable [than a .60 sized plane] and stuff like engine damage is far less likely. If you get either a CYCLON or FORA engine, they just run and run for years. The catch is they need to be run on bladder, but once you get geared up for that, it's routine stuff. For the ultimate in 1/2A power, but also the ultimate in 1/2A frustration [sometimes], the G&Z .061 [full piped version] will get your APC 4.2x4 going at 700 cycles per second [42,000 rpm [X(]] on a good day, but the cost is high in broken parts and spent time to get this level of performance.

RE: 1/2A SPORT / SPEED PROP JET
 

Been busy doing final details...made a spinner, which took more time than I want to talk about........and of course ironing on the monokote. There isn't much left except nit picky little stuff like decals, trim and the tail nozzles. A guy in the 1/2A forum suggested coffee creamer containers, like you see at 7-11 for the tail pipes, sounds good to me!

RE: 1/2A SPORT / SPEED PROP JET
 

Looks very cool CP[sm=thumbup.gif]

Glad to see your wife shaved her wrist.:)

RE: 1/2A SPORT / SPEED PROP JET
 

A question that concerns me CP - you are planning to use a park flyer Rx. Some of the antenna will be internal, and you have silver covering on it which is typically achieved with aluminum flake - i.e. you have a Faraday cage for a fuselage. I can't help being highly concerned for the Rx range. I's heard talk before about them metallic coverings attenuating the signal. I think with normal dual conversion gear the range is so high in the air that any small loss in signal strength typically goes unnoticed.

Any of you RF electronics folks have thoughts on this?

MJD

RE: 1/2A SPORT / SPEED PROP JET
 

You don't know CP too well[8D]

RE: 1/2A SPORT / SPEED PROP JET
 

Nope, I don't. Maybe he's got it all under control. Just concerned is all, it's a fine looking airplane.

RE: 1/2A SPORT / SPEED PROP JET
 

You make an interesting point, MJD. I have no clue if it could be a problem, I know that taping the antenna down with duct tape is a no-no, it caused a complete shutdown on the work bench one time. What I should do is try this RX out with a silver covered plane that I built a couple of years ago. I just flew my .15 powered DIAMOND DUST JR. with the FEATHER RX and all was well at 80 mph, but that plane is done in black covering. With the FEATHER RX, I let just about the whole antenna hang out. I had this antenna routed in the wing [like a big loop] of the 7 ounce 1/2A delta and the range was limited to about 200-300 feet, which is about a third of the advertised distance.

VICMAN, if / when this one goes in, we're gonna have gopher stew!

RE: 1/2A SPORT / SPEED PROP JET
 

Yeah, may be the same deal with duct tape. Although, depending on conditions, it can also generate and hold a fair amount of static electricity as you peel it off the roll, maybe that's playing a role in the shutdown you noted. However, if it is the silver kind it might be getting that color from some % of flake metal, so could be the same issue as for the covering. Not sure.

Personally - I would worry about this a bit. I use FMA M5 Rx's for most of my small stuff as they are dual-conversion and seem to do the job quite well. I know some have lodged grumbles about them but mine work fine. I don't trust parkie Rx's except on my [go figure] close range flying electric parkies.

Whatever happens - good luck!

MJD

RE: 1/2A SPORT / SPEED PROP JET
 

More "work" done. Got a clerk down at STAPLES to spend quite a bit of time to get the lettering patterns made, the bill came to 26 cents [8D]! Then the pattern was glue sticked over monokote and Xacto'd out. Now it is time to paint the cowl and tail pipes.

RE: 1/2A SPORT / SPEED PROP JET
 

Hey CP that is lookin really sharp and FAAASSST

RE: 1/2A SPORT / SPEED PROP JET
 

HI HB!
Hopefully it won't be all show and no go.........I'll be happy if it flies well enough to come home in one piece instead of in a trash can liner. ;) If this one goes in....we're gonna have some gopher stew!

RE: 1/2A SPORT / SPEED PROP JET
 

though I'm no expert , there is nothing to suggest that it wont fly well, looks like it could be a handful though[X(]

RE: 1/2A SPORT / SPEED PROP JET
 

It's kind of uncharted territory for me, I've never built a plane with so much area ahead of the CG. Hopefully there is enough junk in the trunk to keep it on the straight and narrow? The other issue is the stabilators. Are they big enough, too much travel, not enough, etc.?

RE: 1/2A SPORT / SPEED PROP JET
 

I thought the same thing when I started the F20, if yor CoG is ok then it shouldn't suffer from sharp pitching movement

RE: 1/2A SPORT / SPEED PROP JET
 

No Stew for You!:D