Leadouts' Are they necessary?

[frank mccune]

     Hello All:

     In the past, tradition dictated that planes have leadouts installed on the bellcranks.  I have noticed a trend to omit leadouts and just connect the flying lines directly to the bellcrank. Is there anything wrong with doing this?

                                                                                                                                    Tia,

                                                                                                                                    Frank

[Motorman]

Yes there is. The thin flying wires will deteriorate quickly where they go through the lead out guide. They can also deteriorate the lead out guide much quicker in certain cases. I wanted to develop lead outs that have the connector mostly inside the tip where you have to give it full control to connect the lines but, this is for racing, for stunt why would you?

MM 

[bill bischoff]

I have not experienced any of the aforementioned problems, and will continue to connect lines directly to the bellcrank on racing and carrier airplanes.

[BillLee]

Yes, Bill, and we've been doing it for at least 50 years. So it must OBVIOUSLY be dangerous! 

(Where is the "Oh, good grief!" icon?)

[frank mccune]

    Hi B&B and MM:

    I have been seeing planes W/O lead outs for many years and always thought that it was a good idea. KISS

    I recently picked up a Twister that has .015" control lines for lead outs.  I thought that I would run it past you guys for your opinions.  As long as it passes the pull test, it must be good.

                                                                                                       Stay well my friends,

                                                                                                       Frank

[bill bischoff]

This is a different situation. The leadouts are not able to be inspected for wear. I would be most concerned about how they attach to the bellcrank. I would consider .015 wire simply looped through the bellcrank to be inadequate.

[Tim Wescott]

As long as it passes the pull test, it must be good.

At the Spring Tune Up in Portland a couple of weeks ago Mike Hazel had both lines come apart at the handle, shortly after passing a pull test.

You can have severely damaged strands that are almost ready to let go that'll still pass the pull test.  Then if they experience a sharp tug (which is what happened to Mike) they can let go.

So you really should do a pull test and an inspection both.

[Motorman]

Yes, Bill, and we've been doing it for at least 50 years. So it must OBVIOUSLY be dangerous! 

(Where is the "Oh, good grief!" icon?)

I'm talking about fast planes not planes from Texas.


MM

[johnt4051]

For the past few years, at least in my region (Pacific Northwest), most combat planes use button bellcranks (the H&R bellcrank/shutoff mechanism). So most planes used in fast, .15 Fast and 80mph combat in this region, at least, do not use leadouts. Come to think of it, most of our 1/2-A combat planes don't either.  Most everyone uses a double loop at the bellcrank, so the ends are pretty much bulletproof.  But in this application, of course, the bellcranks are external and the terminations are easily inspected -- and lines tend to have a short lifespan for other reasons.  To my knowledge, I have not seen a failure at the button.  fwiw.  

[john e. holliday]

Big difference in button bell cranks and what I consider normal bell crank hook up.  As stated, on the button cranks there is usually a double loop of line.   In racing we are no moving the bell crank like you would in stunt.   The way john describes their use in their combat sounds reasonable as the lines can be inspected.  Yes he may have had a set separate during a hard snap of the lines at the handle.  No regular pull test is going to find that.  I personally had a 1/2A stunt plane break both .012 cable lines when the plane hit the end of the lines.   Must have been a weak spot in the cables as they broke away from the wraps.   If you don't want your lead outs to show for appearance judging, just tuck them in side the slot where the adjustment is.   I stuff mine into the slot while I'm finishing a plane.   

[Steve Helmick]

At the Spring Tune Up in Portland a couple of weeks ago Mike Hazel had both lines come apart at the handle, shortly after passing a pull test.

You can have severely damaged strands that are almost ready to let go that'll still pass the pull test.  Then if they experience a sharp tug (which is what happened to Mike) they can let go.

So you really should do a pull test and an inspection both.

I'd be curious to know if Mike's lines were crimped on wrapped, if anybody knows. I haven't seen many line failures at stunt contests.  Steve