stunthanger.com
Building Tips and technical articles. => 1/2 A building. => Topic started by: Bill Little on August 10, 2010, 03:19:07 AM
-
Yep, it's me again! n~ LL~ LL~
Help me out, please. I need a ball park figure on the fuel needed (type and brand of fuel will be nice, also) to fly the full AMA pattern (about 5 minutes with the 1/2A-1cc ships???) using a:
Norvel .061
Norvel .061
Cox Medallion .049
Thanks!
Big Bear
-
Cox Medallion .049
I seem to recall it took around 1.75-2 oz of Cox Racing Fuel.
Brett
-
As has been stated many times before. It depends on the plane, prop and area. I have a plane with 1.5 ounce tank with a Medallion .049 with Tee Dee p/c that runs for at least 8 minutes in the air. Have a Baby Flite Streak with Brodak .049 with 1 ounce tank that flies for almost 10 minutes. Breaking in a new Mk II Brodak .049 that is running for almost 3 minutes on 1/2 ounce of fuel on the ground. H^^
-
Hi Bill,
I have a 2 oz cylindrical Sullivan on the Norvel .061 Pathfinder and RM207.
It provides "excess volume" and can be short tanked to the time you want.
A 1 oz will not provide enough time if you run them at 23500rpm on the ground, 25000 in the air.
But then, knowing you, you could fab one to the size you need, approx 1 1/2 oz.
e-mail me if you want to discuss further.
Roger V.
-
The Norvel and Wasp engines are pretty efficient. I run 10% Nitro in the Wasp, and can do the pattern on 3/4 ounce of fuel on 45 foot lines. If you up the nitro and line length, of course your results WILL vary.
The Medallion .049 with TD top end actually takes more fuel than the Wasp, partly because it likes Nitro. The Wasp is my engine of choice.
-
First let me say I don't fly "The pattern". That being said, I have used a Sullivan 2 oz "bottle" tank for years with an AP Wasp 061 and it will run a lot longer than I want it to when it is full (8-10 minutes), propping with a Master Airscrew 6x3.5, running on Powermaster 20/20. Usually by the end, I'm doing back to back to back fig 8's to cure teh dizziness. Said tank is shown below.
(http://i52.photobucket.com/albums/g3/Adduckted/planes/pics009.jpg)
-
Dunno how you guys get such mileage out of your Norvels. My .061s use close to 2 oz. to stay in the air long enough for a pattern. Course I like to run mine a little slow (6x2 prop, 48' lines) and a little rich, like to hear the occasional momentary break into a 4, it reassures me I'm not cooking an engine.
-
I'm with Ray on this one, i use a Hayes 2 oz. clunk when i want to make sure i can go the pattern with my norvel's and wasp's. Using a balloon that is called a 9 ounce, (that may refer to air volume) i can get about an ounce and a half of fuel in it without it having any pressure and that would probably get close but i have not tried the full pattern with that set-up, that will be next on my 1/2a to do list! I also run a medallion .049 mounted with a norvel tank (a little more than a half ounce)on a baby flite streak, seems to me that only runs about 2 1/2 minutes. Oh yeah, i also run 25 to 35 percent nitro in my little ones and also run them a little rich, so your milage may vary alot!! That being said, i don't mind flyin' close to 8 minutes #^
-
I think you will find that is a 9 INCH balloon, not 9 OUNCE. It refers to the inflated diameter at maximum. BTW, I blow up my balloons, tie them off and leave them for a couple of days before using them as a tank. Several plusses. First, you find out if you have a leaky balloon. Second, it stretches the material so the volume is larger. And finally, the walls become thinner and more flexible, resulting in a better run as the tank nears empty.
-
Thanks Larry! You are correct! H^^
-
Thanks for the heads up Larry. I just made my first balloon tank this week to start break in of Brodak .049 that is going to power the Snapper 1/2A. You guys have to see the kit as it is incredible. Light wood and some construction already done. Back to balloon tank. I hook up my syringe and suck out the air. Tip the syringe up to get fuel so it can be put in the balloon. Sitting there watching that little Brodak run and the balloon collasping is something. Hope I can get it to work in the plane as well as it does on the bench. H^^
-
I used a balloon in my last Snapper and it worked out just fine. I also have the Minnesotamodeler Snapper kit, and it is, indeed fantastic.
-
Here's where I am on mine. Wings covered in SLC, ready to start doping. Should have had it done before now. How did we get the planes built so fast before the CA's and 5 minute epoxy? H^^
-
Good lookin job, John. Looking forward to a flight report!