Jerry:

I would say go for it. The larger airplanes actually seem to fly better. You can trim the airplane to not pull very much. One of the best flying control line scale planes that I have had was a 13 pound Monocoupe with a 6 foot wing span and an O S 91 four stroke for power. Flew it at about 1/3 throttle. I think you have the right combination. Go for it, it can be a lot of fun. If you intend to compete with it, make sure you find your documentation for proof of scale.

Jim Fruit

I have experience with two large models:

the first spans 80" and came in at 12 lbs. It was not scale but it flew fantastic with a 90 four stroke. I flew it with a 60 glow and it was under powered. The key on the large models is not the line length, but the AMA wants you to have lines that are 65-70 feet long for competition. Generally I fly the large models with 60' lines with no problem. I have since converted this model to the E-Flite 60 electric motor with a 16" prop, 6S battery it flies at 1/2 power with no problems.

The second was the Sig 1/4 scale Morrisey Bravo, 87" span, 90 four stroke and it came in at 15-16 lbs, flew great also.

The main thing to remember is the adustable leadout guide wiill keep the line tension within reason. If the model flies really fast and weighs 14 lbs it will pull really hard, but larger models fly slower than smaller models. I start with an adjustable leadout guide and move the line guide forward until I have enough line tension to keep the model out there, but no so much that I have to use both hands.

I flew both models with one hand, while the other hand was on the electronic controls transmitter on my hip. If you have to use both hands to hang on then it's flying too fast or the line guide is not adjusted correctly.

If 87" is not large enough consider building the Sig 1/3 scale Spacewalker at 103", A friend built one for CL scale (and still flies it) and it comes in at 18 lbs and it is flown with one hand. again the line guide location is critical. Grant flies this model with the E-Flite E-160 electric motor, the motor is as large as a soup can.

....the 72" span is a great size and the 60 should pull it no problem, just try to keep the weight under 10 lbs.

Bigger flies better.

Fred Cronenwett

Fred, is this big Spacewalker legal under AMA competition rules? I'm wondering whether the weight or power would disqualify it from competition.

Dennis,

Instead of casting doubt on limits on the size of any CL scale airplane, why not check the rules for yourself?  The airplane that Fred described is perfectly legal under the AMA CL Scale rules.  This is how nasty rumors based on unsubstantiated statements get started.  It is all quite clear in the AMA rulebook.

By the way, the CL Scale rules do have a weight limit of 20 pounds.  Also, electric motors of any size can be used.

Keith

Kieth is correct the weight limit for AMA events in CL scale is 20 lbs and re-reading the rules there is no limit for electric power. Grant flies the Spacewalker with an E-Flite 160 brushless motor and a 10S battery if I remember correctly. Wing span almost means nothing, it the overall weight of the model and if flying with glow power you can't be larger than 1.25 cubic inches, if flying with a four stroke you can have up to a 2.5 cubic inch motor. I honestly wouldn't want to fly a model with a 1.25 two stroke for power.

Even if the rules allow these large motors and 20 lbs the 10-14 lb range is the largest I go these days. I retired a model that came in at 80" and slightly over 12 lbs and it was quite large. It flew with a OS 90FX two stroke and it had more than enough power.

I like the 60-70" span range for the larger scale models.

If you do build the Spacewalker you will have to do some swaping out of some of the wood, there is alot of plywood in the kit that is not required and will put the model over 20 lbs if built per plans. I believe Grant built a new wing with Balsa Ribs and other lighter structure in the fuselage.

Fred C.

Keith; It's good to know the Rumor Police are always on the lookout for possible infractions of forum protocol. 
          Hope you have a good sense of humor or I'll be toast again. Anyway, thanks for the rules information.
          I didn't  realize they were on the web. Now I know.

Fred; I'll send you an email regarding information about the big Spacewalker, and thanks for the information you have
         already freely provided. Sharing of information one of the great things about the Stunthanger.

Jerry; I sincerely apologize for the off-topic turn your thread has taken as a result of my first post. I certainly didn't intend
         for this to happen.

Jerry, go to page 8 on this site and you will see my Ryan 200 STA (Sig kit). It flies great with a Satio 91 four stroke. It is fun to fly. Any question, drop me a line.

Blessings
Allen