stunthanger.com

General control line discussion => Open Forum => Topic started by: Dennis Leonhardi on April 14, 2014, 10:07:04 AM

Title: Lines
Post by: Dennis Leonhardi on April 14, 2014, 10:07:04 AM
The topic has probably been discussed many times here, but humor an old man ...  what do you use for flying lines?

1) Engine displacement
2) Weight of model
3) Lines - diameter and length (handle to centerline of aircraft)
4) Sport flying or competition?

TIA!

Dennis
Title: Re: Lines
Post by: Tim Wescott on April 14, 2014, 10:22:47 AM
Your list seems to be a mix of asking what to base the decision on, what one actually uses, and what we're flying.

I use line diameter per the AMA rule book, CL stunt section, EXCEPT that on '20' sized airplanes I use 015 lines rather than 012, per comments by Dan Rutherford about 012 lines being "too springy".

If you don't read the rules, that's weight-based.  There's a handy chart, and the rule book is a free download, so you have no excuses not to get it and use it.

I use length to suit my own preference and airplane performance -- every engine and plane combination has a line length that works well, if you read enough posts here you'll see that the recommendation is to try different lengths.  As a starting point, I've had good success on Skyrays, Flight Streaks and Ringmasters on 60 foot lines when running an OS FP20, but that line length is absurdly long for the same Ringmaster with an OS 25S (the old baffle-port engine).

I'm pretty competition-centric these days -- my "sport flying" pretty much consists of dusting off my #2 or #3 plane and flying the pattern with it.

For all-around sport flying you could do a lot worse than just starting with the recommendations from the stunt rule book.
Title: Re: Lines
Post by: john e. holliday on April 14, 2014, 11:48:53 AM
Do as Tim says and get the rule book down loaded and read.   After reading it the first time go through it again and see what you missed.   I quit using .012 on anything bigger than a .25 size engine.   Seems I have better control with heavier/thicker lines.   Yes, I tried the .012 lines and use them on the .15 size planes.
Title: Re: Lines
Post by: Brett Buck on April 14, 2014, 01:52:36 PM
The topic has probably been discussed many times here, but humor an old man ...  what do you use for flying lines?

1) Engine displacement
2) Weight of model
3) Lines - diameter and length (handle to centerline of aircraft)
4) Sport flying or competition?

TIA!

Dennis


   I am not entirely sure what the question is, but most people are running stranded lines on "full tilt" stunt planes, usually 0.018 7-strand. There are a few that still use solids (.014 SS). This includes people that could hypothetically use .015 stranded (below the 64 oz breakpoint).

   Mostly, these airplanes run on shorter than max length lines. Most people measure the lines from eyelet to eyelet, and many are in the 63-64' range. 67' 6' is about the max, measured this way.

    Of course you can find people with varying opinions, these are just generalities.

   Brett

   
Title: Re: Lines
Post by: Bill Little on April 14, 2014, 02:01:20 PM
Hi Dennis,

A while back the AMA regulations changed the requirements to be based on the model's weight, NOT engine displacement.

The old manner is still pretty close if you cannot weigh the model, except when the model is excessively heavy.  If in doubt, go to the larger lines.

BIG Bear
RNMM/AMM
Title: Re: Lines
Post by: Dennis Leonhardi on April 14, 2014, 03:55:17 PM
Thanks for the input guys.  I'm well aware of the rule book and weigh all of my airplanes to an extreme, but - maybe being an old combat flyer - have tended to use heavier lines than required.

Tim's remarks are really what I'm looking for - been tempted to fly some of my lighter airplanes on .012 lines, will look for the "springy" issue.

Also coming to the conclusion that line length is more sensitive than I would have expected.

Dennis
Title: Re: Lines
Post by: Bill Little on April 14, 2014, 04:18:54 PM
Dennis,

I can actually tell a difference between .015 and .018 on a large stunter.  It is legal to use .015, but the .018 feel "better".

BIG Bear
RNMM/AMM
Title: Re: Lines
Post by: Jim Thomerson on April 14, 2014, 07:42:00 PM
With stunt line lengths in the 60 ft area, the approximation that a one foot change in line length makes a 0.1 sec change in lap time is fairly close.