I received a gimme Flite Streak ARF a few years ago with an FP-25 on it.  The donor and a few other pilots had done "Flite Streak Only" combat matches using ARFs and FP-25s.  I first flew it about three years ago, but only put on one flight.  Last September, I decided to give it a go and fly it in my first attempt at Beginner Pattern on a lark.  It jumped off the ground and I could barely control it.  It was like it had an undersized bellcrank for the combat the previous owner used it for.  I'm a 1/2A flier for the most part, but I shouldn't have had that much of a problem, as I had a FS ARF a few years ago and had no problems with that one.  So after the disastrous effort, I put it in the corner.  A couple of weeks ago someone asked if I was going to try Beginner's again this year, so I pulled the plane out of the corner and took a good look at it.  The person who gave it to me had glued down the bellcrank inspection hatch instead of screwing it down so I couldn't look at the bellcrank, but the leadouts aren't like the ARF leadouts from the previous ARF I had, so they must have replaced the leadouts for the matches.

Then I took a good look at the control horn.  No wonder!!!  It has a 1/2 inch 1/2A control horn.  That's going!  So I pulled a 1 1/2" horn from the spares drawer to fix things.  But I can't find my old manual from the FS ARF, so I have no idea of how much throw the elevator should have.  What is the understood amount of throw I should shoot for on the elevator?

Mark

I had a lot of fun with Flite Streak combat back in the day.  It probably has a 2" ballcrank. You should be able to tell by the leadout movement.  The most a 2" will go is 1" per leadout.  You have the right answer - a new horn.  Set if so that you have 1/4" up/down at the TE and lots of holes to make it more if you want.  Another thing is the CG. Mine balanced about 1" behind the LE.  Start there and add clay to the tail as needed.

Ken

We are talking the 40" wingspan jobbie, right?

1 1/2" horn?  Whut?  You want about a 3" horn, line hole to line hole.  If you're measuring 1 1/2" from center hole to line -- it's a 3" bellcrank.

+/- 30 degrees should be fine.  I'd put a nylon horn on the back and adjust throw as necessary.

The ARF recommended a crazy-rearward center of gravity -- I was told very emphatically by Dirty Dan Rutherford that you want the CG 1 5/8" back from the leading edge at the wing root.  I followed instructions, and ended up with a nice flying airplane.

Quote from: Tim Wescott on June 03, 2026, 08:13:45 PMWe are talking the 40" wingspan jobbie, right?

1 1/2" horn?  Whut?  You want about a 3" horn, line hole to line hole.  If you're measuring 1 1/2" from center hole to line -- it's a 3" bellcrank.

+/- 30 degrees should be fine.  I'd put a nylon horn on the back and adjust throw as necessary.

The ARF recommended a crazy-rearward center of gravity -- I was told very emphatically by Dirty Dan Rutherford that you want the CG 1 5/8" back from the leading edge at the wing root.  I followed instructions, and ended up with a nice flying airplane.

   You mean bell crank, not control horn?? The ARF does come with a 3" bell crank, and the control horn is too small, and I replaced that, in addition to bushing the lead out holes in the bell crank. The CG in the instructions is way too far back and part of Mark's problem. The Streak is one that can handle a forward balance point well. I use two wheel landing gear also. Mine has a LA.25 on it and it's more tame than the FP.25. To tame down the FP, use a smallish venturi, and start out with a APC 9-4 prop and experiment from there. Stacking on some head shims might help also. Lines that are on the longish side will slow the airplane down also, 60 ft. eye to eye and 4" line spacing or less on the handle. A lot has been posted comparing the LA.25 to the FP-25 over the years, and I feel the FP-25 is the hotter engine, by a good margin.
  Type at you later,
   Dan McEntee

Quote from: Dan McEntee on June 03, 2026, 08:25:51 PMYou mean bell crank, not control horn?? The ARF does come with a 3" bell crank, and the control horn is too small, and I replaced that, in addition to bushing the lead out holes in the bell crank. The CG in the instructions is way too far back and part of Mark's problem. The Streak is one that can handle a forward balance point well. I use two wheel landing gear also. Mine has a LA.25 on it and it's more tame than the FP.25. To tame down the FP, use a smallish venturi, and start out with a APC 9-4 prop and experiment from there. Stacking on some head shims might help also. Lines that are on the longish side will slow the airplane down also, 60 ft. eye to eye and 4" line spacing or less on the handle. A lot has been posted comparing the LA.25 to the FP-25 over the years, and I feel the FP-25 is the hotter engine, by a good margin.
  Type at you later,
   Dan McEntee

Mark said bellcrank in his original post, and I did not think that maybe he meant the control horn. If he meant control horn then his post makes a lot more sense.

Your setup is about how I flew mine, and it worked quite well for me.

The plane may have been modified for combat and have a 2" bellcrank.  Best check.

Ken

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