News:


  • February 27, 2021, 11:15:47 AM

Login with username, password and session length

Author Topic: My First Try at a 1/2 A Stunt/Sport Plane  (Read 1215 times)

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
My First Try at a 1/2 A Stunt/Sport Plane
« on: April 26, 2020, 05:22:36 PM »
Here are some details.

Original In-Line design.
Power: OS .060.
Weight: 7 3/4 ounces.
Wingspan: 29 1/2 inches.
Overall length: 17 3/4 inches.
Chord: 6 inches (constant)
Trike gear because small planes like to flip over in grass!
Prop: TBD.

Hopefully I'll fly it in a day or two.

Bob Z.


Advertise Here

Online Motorman

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 6175
  • Millville NJ PDQ Flying Clown Country
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #1 on: April 26, 2020, 05:27:11 PM »
Unique and wonderful.
Remove victim to fresh air

Offline Clint Taylor

  • 2018 Supporter
  • Trade Count: (0)
  • New Pilot
  • *
  • Posts: 10
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #2 on: April 26, 2020, 07:46:11 PM »
That's a very neat design!

Online ray copeland

  • 21 supporter
  • Trade Count: (0)
  • Captain
  • *
  • Posts: 846
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #3 on: April 26, 2020, 09:29:33 PM »
Awesome Bob! Nice weight for 1/2a. What tank you gonna try? The little apc props work well, may need to make a bushing and sometimes the cox 5x3 rubber ducky will give good results.
Ray from Greensboro, North Carolina , six laps inverted so far with my hand held vertically!!! (forgot to mention, none level!) AMA# 902150

Offline Larry Renger

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3830
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #4 on: April 26, 2020, 09:43:17 PM »
With the short tail length and small tail feathers, start with pretty narrow line spacing at the handle and work your way out. Otherwise it is a beauty! Keep us posted on how it flies.

I have no experience or information with that engine, so am very interested in what performance you get.
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

DesignMan
 BTW, Dracula Sucks!  A closed mouth gathers no feet!

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #5 on: April 27, 2020, 07:59:32 AM »
Thanks to all for the compliments and good advice.  #^  #^
Ray: At this point, I have a Top-Flite 7-6 wood prop, which I will cut down to 6 1/2.
It's a bit nose heavy so I'll stick with wood for now.
I did fabricate a bushing from 1/2 inch hex-stock aluminum since the shaft thread (8-32) is a bit short.
Larry: I have set up the controls to be quite slow but I will take your advice and keep the handle spacing narrow.

Bob Z.

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #6 on: April 27, 2020, 09:40:52 AM »
This is how I mount all my engines now.
Shown is the OS Max 061 and I'm also doing an LA 46.
Simple, light and reliable.

Bob Z.

Offline Mark wood

  • Trade Count: (0)
  • Lieutenant
  • ***
  • Posts: 108
  • I'm here purely for the fun of it.
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #7 on: April 27, 2020, 11:07:04 AM »
Way cool. What did you finish it with?
Life is good
AMA 1488

Offline Larry Renger

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3830
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #8 on: April 27, 2020, 05:16:15 PM »
Wow, a 7-6? I suspect a 6-4 would be more like it. The AP Wasp,and Norvel use much smaller props even than that. 5.5-2.5 and 6-2 or 5.7-3
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

DesignMan
 BTW, Dracula Sucks!  A closed mouth gathers no feet!

Offline pmackenzie

  • Pat MacKenzie
  • 21 supporter
  • Trade Count: (0)
  • Captain
  • *
  • Posts: 569
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #9 on: April 27, 2020, 06:09:34 PM »
This is how I mount all my engines now.
Shown is the OS Max 061 and I'm also doing an LA 46.
Simple, light and reliable.

Bob Z.

How do you get to the nut (in the model) to tighten it up?
MAAC 8177

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #10 on: April 27, 2020, 09:10:53 PM »
Quite simple - see the photo.

Offline Larry Renger

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3830
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #11 on: April 28, 2020, 04:54:51 AM »
Wow, that is a really small tank. How much run time do you get?
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

DesignMan
 BTW, Dracula Sucks!  A closed mouth gathers no feet!

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #12 on: April 28, 2020, 07:50:31 AM »
Hi, Larry.
The look is deceiving.
The tank actually extends around a half inch further back than is seen in the photo.
You see, the lead edge does not protrude into the fuselage.
As far as run time, I have only run the engine on the bench at this point.
If the present tank is insufficient, I can fabricate and fit a larger one.

Bob Z.

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #13 on: May 18, 2020, 08:27:31 AM »
Well, I finally got to fly it and I am really pleased.   #^   #^
First flight was a bit rich so I just let it run out.
Second flight PERFECT!   y1
It turns extremely tight with no noticeable loss in speed.
I was able to do most of the pattern but ran out of fuel before I could finish.
40 ft lines are too short. I will make up a set of 45 foot lines using 15 Lb spider wire instead of .008 cables.
6-4 Top-Flite wood prop, 25% nitro.

Another report to follow.

Bob Z.

Offline john e. holliday

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 21476
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #14 on: May 18, 2020, 09:33:58 AM »
Looks like a winner. H^^
John E. "DOC" Holliday
10421 West 56th Terrace
Shawnee, KANSAS  66203
AMA 23530  Have fun as I have and I am still breaking a record.

Offline Larry Renger

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3830
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #15 on: June 05, 2020, 09:42:38 PM »
Try lower nitro to get longer flight time and somewhat saner lap time, unless line tension is an issue. Keep us posted on how it is going!  H^^
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

DesignMan
 BTW, Dracula Sucks!  A closed mouth gathers no feet!

Offline Larry Renger

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 3830
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #16 on: June 19, 2020, 07:18:49 PM »
Any news on later flights?  H^^
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

DesignMan
 BTW, Dracula Sucks!  A closed mouth gathers no feet!

Online FLOYD CARTER

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4195
    • owner
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #17 on: June 20, 2020, 06:06:40 PM »
Conventional gear 1/2A models do flip over on grass.  So what?  They don't get hurt.
"Growing old is easy.
 Staying old is hard"
AMA #796  SAM #188  LSF #020

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #18 on: June 21, 2020, 10:49:06 AM »
Conventional gear 1/2A models do flip over on grass.  So what?  They don't get hurt.

Yeah, but the landings look a hell of a lot better!
Anyhow, I flew the plane on the 46 foot lines I mentioned earlier.
It really flies well but is still too sensitive - the reason I suspect, is a bit tail heavy and the controls a bit to sensitive.
I put a Master Airscrew prop on it and a longer elevator horn.
The weather in SC has been terrible - lots of wind throughout  the day.
I'm in Florida now but I'll be back home soon and will try out the mods as soon as possible.
« Last Edit: June 25, 2020, 06:36:58 AM by Robert Zambelli »

Online goozgog

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 490
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #19 on: June 23, 2020, 02:14:15 PM »
Hey Bob,

That is a little gem of a stunter!

   My Focke-Wulf is very sensitive
even with a handle spacing of
2.25 inches.
  Your plane is even lighter than mine.

 
Joe Eiben, the electric scale flyer who usually has
a table at Brodak's, pointed out that the
drag of the L/G will affect the maneuverability
of a very light plane.

  The 9.0 oz Focke-Wulf turns VERY tight
outside corners that are hard to dampen.
I'm deluding myself that
"All little planes are twitchy!"  <=

Keith Morgan

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #20 on: June 25, 2020, 02:44:04 PM »
Way cool. What did you finish it with?

Hi, Mark - sorry for the late reply.
I guess I just overlooked it.
Anyhow, to answer your question.
The finish is quite simple - just light silkspan and Brodak dope.
I added some .5 ounce fiberglass reinforcement to the nose section.
Bob Z.

Offline L0U CRANE

  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1019
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #21 on: July 09, 2020, 02:00:39 PM »
IMHO, the reason so many "little" ukies feel twitchy and over-sensitive is that they too often have "1/2A" size bellcranks and horns.  I don't really understand why the "1/2A" stuff was done, except to "look like" it was more suitable for a smaller model.

For originals - of course - you can design-in space for "large ukie" (say 3") bellcranks, and use matching horn sizes. Those are the proportions, movements and feel we learned with our usual first successful model.

For external controls, like many profile and sheet wing 1/2As, you are free to relocate the bellcrank  a bit further from the fuse to prevent hitting it at full throw, or aft a bit if you don't like to see a bellcrank arm from above the model

Cramping the lines close together at the handle can do the same thing, but starts with a very narrow range of adjustability. Say the model flies with a noticeable non-level attitude, for example. Close spaced lines at the handle might not allow you to change wrist/finger grip or angle far enough to get it to fly level.

Sure, "full-size" hardware weighs more, but just how much more? Compare the added fraction of an ounce with repairing  or trashing a model for being too twitchy.

Try it, you might like it...
\BEST\LOU

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #22 on: July 10, 2020, 02:51:59 PM »
Thanks for all the good advice, Guys.
The plane is well dialed in now.
I lengthened the elevator horn, lengthened the lines, put in some engine offset, removed some tip weight and added a bit of nose weight - an APC 6-4 prop.

It really flys well now and I think I can go a bit longer on the lines - they're 46 feet now.

Bob Z.

Offline Dane Martin

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2827
  • heli pilot BHOR
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #23 on: July 10, 2020, 03:15:49 PM »
Outstanding work, as usual.

Al F. posted a reply on the line length post. Similarly equipped plane on 48' lines.  So I would guess you'd be good to go longer

Offline Robert Zambelli

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2296
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #24 on: January 21, 2021, 02:22:12 PM »
Hi, All.

Since I've been away from planes for a while, I hadn't done much with the little stunter.
It flew well with the OS .061 but someone gave me a Norvel .061 so I'll try that.

IF, we ever get some decent weather!

Bob Z.

Offline GallopingGhostler

  • 21 supporter
  • Trade Count: (0)
  • Commander
  • *
  • Posts: 226
Re: My First Try at a 1/2 A Stunt/Sport Plane
« Reply #25 on: January 22, 2021, 12:42:29 PM »
Concur with comments, that is a really sharp looking half-A stunter you have there, Robert, and with the rarer OS (Pet?) .061 nonetheless.

(OT) I purchased an OS Pet .06 from the now defunct Hobby Shack, Fountain Valley, CA in 1973. It was for my 36" GB Jr. Falcon R/C. To my surprise, they substituted without cost an OS Max .10R/C (1965 version) with butterfly valve exhaust restrictor coupled to the R/C carb. I powered the Falcon with a Cox .049 Golden Bee instead, but put the Max .10R/C in a 39" Top Flite Schoolmaster all sheet. Flew it on Ace R/C Pulse Commander rudder only with KRD sequential quick blip throttle servo. Wow, what an engine, full throttle it climbed out at 45 degree angle, half throttle like a .049, and whisper quiet at idle for low passes. Yet, at full throttle, its noise was only that of an unmuffled Cox reed valve .049. It is such a great engine that I have 3 of them.

Sorry for departing off topic. I imagine that OS would also make a decent C/L engine as well, being as strong of a cross scavenged engine as it was. Need to get off my duff, but got an original 36" Sterling Profile P-38 and 2 Enya .09-III with venturi intakes reserved, and get it built.


Advertise Here
Tags: