stunthanger.com
Speed,Combat,Scale,Racing => Carrier => Topic started by: Pat Johnston on April 07, 2011, 12:40:23 PM
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I just modified my plans for the S-2 Sterling Mustang specifically for Carrier. I am showing details as I would set this one up for carrier use. I felt the S-2 Mustang was potentially one of the best carrier subjects available in the "good old days" of carrier in the late 60's and early 70's. I am attaching a PDF set of plans for those wanting to see this one. Copies of the plans are quite available.
Pat Johnston
Branching Out
Skunk Works
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Nice job Pat. I modified a Sterling Mustang back in the early 70's and flew it in carrier. Not a world beater but nice flying plane. I would think it would be a good candidate for Nostalgia Carrier. 8)
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I too have liked the Sterling Mustang for Profile Carrier. I morphed one and wrote about it in one of the first isses of CLW. Dave Miller flew it well at a contest in Portland 2 years ago and I will be taking it to Portland next week. I found the LA .25 an excellent engin e for novice usage. Thinking ahead a bit I may make a run of them for next season. this years efforts were for a run of Wildcats that have received sme very nice feed back. Foam wing of course.
Joe
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Very nice drawing Pat! However there are a few problems that need to be taken care of. First it needs to be noted that there needs to be three W-7 wing ribs made. One for the right wing and two for the left. The line guide is supposed to slide into this space between the W-7 ribs on the left wing. Also no pattern is given for the line guide. I personally don't like plywood control horns but that is "stock" Sterling. I won't use them because I have seen many break.. I also think the landing gear would not hold up for carrier operations and would use the design like the Brodak Grumman Guardian uses.The idea of having the flaps coupled with the elevator like a stunt ship works very well, I don't know why it isn't used more. Thanks for the drawing, I hope to see some built and flying. Mike
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Mike,
you will, Pat and I have been scheming,, muah ha ha,,* sinister laugh*
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Maybe one with a OS40fp mounted in the nose?
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Mike,
Here are the final drawings for the Mustang. I made up the leadout guide, put a carb on the FP40, hooked up the carb linkage. That should get it along pretty well. I would install plywood tabs to bolt the leadout guide plate to so it can be altered. Instead, I am showing a fixed plate which will suffice nicely overall. I may do some little alterations to the plans, but they are 99% done.
One question... The old J-Roberts system called for 2 1/8" longer throttle line. The new Brodak unit calls for a 1 27/32" longer line. I have a Brodak bellcrank and a J-Roberts handle. What does this mean? Of course, I can always use longer or shorter line clips to fine tune the whole system. Figured you should know...
Pat
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Hi Pat, nice.....
Something you might think about is making the tip weight box larger. I put a standard square stunt ship box like you show on the plans in the big FJ-4. While at Brodaks last year discovered I couldn't cram enough led in it for a carrier airplane. I have now buried a 1 1/2 oz chunk of lead in the outboard tip and hoping it along with what I can get in the box will be enough.
I'm a new kid on the block but my understanding is you can get away using a Brodak Bellcrank with a J-Roberts handle. The throw on the belcrank will be more than the handle so you just use what throw you have available at the handle when setting up the throttle linkage.
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The leadout length specifications really confuse the issue. You can make the leadouts any length you want. Here'e what's important: Lay your handle on the workbench, and pull the trigger all the way back. Measure the difference in the lengths of the up and down cables compared to the throttle cable. Now push the trigger all the way forward and measure again. Note that when you push the trigger forward, the throttle cable retracts into the handle and the up/down lines extend out. The movement of the throttle cable relative to the up/down cables is what you want to measure. Now, do the same thing with the bellcrank. If the measurements match, you're all set.
The old, original J-Roberts handles and bellcranks have less movement than the G&S/ L&R/ Brodak handles and bellcranks. (Unfortunately, Brodak clouds the issue by labeling their handles "Brodak-J-Roberts".) If you use and "old" handle with a "new" bellcrank, you won't get full throttle travel coming from the bellcrank. This can still be made to work, as long as you get full travel at the carburetor. However, if you use a "new" handle with an "old" bellcrank, the bellcrank will "bottom out" at one or both ends of the throttle travel. This will cause line(s) to go slack, which is a bad thing. If the pilot is aware of the possibility, he can work around it.
All that being said, it is best to use stuff that matches. It's tricky enough to make it all work anyway, so why make it harder?
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Or, as many have done in the past, and many of the plane plans available use the system, you can use the home made variety of 3-line bellcranks as shown in the attachment. These work with any handle you have or may build yourself. While I highly reccomend the Brodak system of BC's and Handle the home made variety is just fine for either .15 or .36 size profiles. Cant say that anyone has ever reccomended these for Class 1 or 2! In a CD I have many of the older profile ships use the pictured system. I use them myself, making them from both Penolic board and by using two Perfect or Fox bellcranks. Be assured, there is no nbeed for any spring loading, and the two bellcrank arms move forward and backward as you apply in put from the handle. Are these the best thing since sliced bread? NO, but they are a lot of fun to make, use, and in a novices hands, quite a bit cheaper!
Joe Just
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Pat, the method Bill outlined works fine. I use the Brodak handle and bellcrank on everything and a 2 1/8 measurement with the up down lines pulled tite.If you can make line clips that is the way to go for adjustment. Also be aware that all Brodak handles are not created equal. If you try to use another handle things may not work correctly.On my latest airplanes I run the lines directly to the bellcrank,no leadouts. To do this you need to unroll the lines to 60 feet and match cut and crimp them to the handle.
See you in Portland Sunday!
Mike