ALL,
Continuing from last night. First, did not mean to confuse anyone about airplane weight, the 24 Oz was a maximum model weight ala AMA calculations, as noted in the last sentence.
As for stranded lines, unless the latest AMA rules have changed it, the only racing event allowing multi strand lines is 1/2A mouse racing. I see Combat uses stranded 0.015 so they are available. The real safety issue is, as Bill Hughes says, not how the bellcrank is attached, but insuring that the airplane, lines and handle pass a reasonable pull test prior to flight. I don't have any breaking strength information on stranded wire but note that AMA calls for a standard 25 pound pull test on 0.015 multi-strand in .15 Combat (This may have changed in latest rules), based on 60 foot lines and a four pound maximum aiplane weight. (For the numbers to work in this class, a four pound airplane would only be pulled 6.25G, which is scary) If AMA considers 0.015 multi-strand only good up to 25 pounds pull test and max Perky weight is 24 oz, this works out to only 16.7G (20G for a 20 oz airplane), way under AMA calculations.
Next step is for the advocates of multi-strand to provide breaking strength data similar to what is available from AMA for solid ASTM wires.
Will Stewart