H9's Sundowner

[Leseirf]

I've been wondering about that myself. We have Eagletree data that shows 129mph at 9700rpm. That doesn't add up. Should be more like 110mph at that rpm. Yet the race time sheets I've seen show well into the 120's occasionally hitting 130.

Mike

[nesikachad]

Hi guys.

I'm new here and I'm hooked on this plane. I've already (I hate saying this) destroyed two of them. First was on a Saito 180 (totally my fault) and the second was on a Evo 35GT and I got "hit" hard by a militant signal.

Anyways. I've got my new one and when I get home this fall (in Iraq) I intend to set it up for racing.

Is the USRA still running the SD class? I can't seem to find much info on the website.

Appreciate any info and help.

Cheers,

Chad

[Leseirf]

Still racing Sundowners. There were 5 in Ashtabula a few weeks ago. Be nice to see more. Next race is on the El Mirage dry lake bed in CA Oct 30- Nov.2

Current rules are here.
http://www.usrainfo.org/sundowner.htm

It's been opened to any stock engine under 35cc so bring what you have and let's race!
Mike

[Captinjohn]

Here is a link to the last USRA pylon Race in Ohio http://www.rcignitions.com/forum/album_cat.php?cat_id=1 I hope it works Capt,n

[Captinjohn]

I am wondering about the URSA engine rules(35cc)
12a.3 ENGINES (internal Combustion) – Any commercially available 2 stroke or 4 stroke gasoline or glow engine up to 35cc or 2.1 cu in will be allowed. Engines must be unmodified. The original mfg’s recommended fuel type must be used for the engine being used; converting gasoline engines to glow will not be permitted.
12a.3.1 MUFFLERS – Only commercially available mufflers can be used. No tuned pipes or tuned mufflers are allowed. The aircraft must pass the AMA max noise limitation at full throttle. .....Question.... Can a 35cc gas engine of any type be used with a cd ignition installed by owner? Thanks Capt.n

[race101]

CJ
For this year all engines are to be stock. We are evaluating rules changes for next year after the Ca race in Oct.

[teuchter]

That’s my one finished now and fly’s real nice; no idea of the speed, though does cover a lot of ground quickly.
I fitted the tank butted against the wing tube and used a perry blue can to feed the Moki 210, static revs are 8500 rpm’s on an apc 17 x 13" and hogs nearly 3oz fuel a minute.. ..

[Sparky69]

3 OZ a Minute! No problem! I have a race plane that will down fuel faster than An Irishman at the free beer day! (about 2 Liters in 6 minutes) From my testing you are most likely doing around 125MPH or so in level flight. Enjoy your plane. What fuel do you use and what does it weigh?
Sparky

[teuchter]

Cooler over the pond here with temps seldom over 15c so straight 80/20 methanol/castor fuel is a no no!
Fuel is 5% Duraglo supplied from here ttp://www.modeltechnics.com/glowfuel/glowfuel.html which I added extra castor.

This engine is new and I doubled up on the standard head gasket/shim for now; no ping at these revs so far’ and will try again with the extra head shim removed and perhaps a little leaner to tease out some more rpms and will wok forward to adding as much extra % nitro that I can get away with.

I am using Towerpro MG995 budget digital servo’s all round which are plenty heavy and fitted the lighter hollow tail tube.
The tank is butted against the tail tube which messed the book cog and the battery is a heavy rearward mounted 4300 4.8v Sub C Nimh weighing some 244grms/8.6oz

I’ll get the rtf weights for next post.

[teuchter]

Had to huck a shotty of scales from work; this set is calibrated and spot on! .. Dry weight 6.132 kg’s / 216.3 oz / 13.52 lbs.

[Capt.GM]

I got my SD F1 fly with Moki 210 and pitt muffler with 16 x12 APC ..this plane fly's great I also got SD 50 both fly the same characteristics its amazing ..

[nesikachad]

How are landings with the Moki?

Mine had the Evo 35 and was a tank with wings.

[proptop]

Got a Moki 2.10 in mine, with an APC 16x14 and Bisson Pitts muffler. Running on Omega 5% w/ 4oz. extra Castor...O.S. type F plug.
Flys quite well w/ the CG @ 3.25" (empty) and landings are not as bad as I'd heard/anticipated, once it finally gets slowed down. The Moki takes a little while to come down in r.p.m. and with that prop there's not much braking. It will snap if I horse it around, but ya just gotta remember not to do that.
Mine weighs around 14 1/4 RTF.

[nesikachad]

Prop,

Thanks. As far as the snapping. I've read this is a demon that lives in this airframe. One "cure" that seems to work is moving the CG forward a bit.

When you say "RTF" does that include fuel too?

[Sparky69]

Yep the cg should be 3.25 with the tank empty. If you are running the Moki you should install the hollow tubes in the tail and put the battery pack as far aft as required to balance. On mine it was on the tail hatch but it saved a lot of weight for CG adjustment. USRA Spec prop is APC 17x12 and is the fastest prop I tested last winter with the Moki before I quit testing.
Sparky