Ask Dale Campbell from Huntersville, NC. (I think that is were he is from) about the building or the flying of the Sig Ryan. He gave me good information that I found to be true with this airplane. 7lbs, hum,? don't know about that. My Ryan has two batteries on board, one for the engine and one for the z-tronic controls, three servos. Wing tip weight, when you drag three lines, or coated two lines on a scale ship, you better have adequate weight in the outboard tip. And to help, set the ailerons (inboard slightly down and the outboard slightly up). Ask Steve Couch from Indianapolice, he lost a beautiful SE-5A at the Nats a couple of years ago due to this factor. Jack Sheeks told me many years ago start with more weight up front than you think you need then take out as you flight trim. One time up with a tail heavy airplane will make for more work than you want. In watching R/C scale and C/L scale at the FAI world championships in Muncie in 1994 (?) one common factor, under powered and tail heavy. Scale makes for a fun day of flying, IF the airplane is trimmed right. On the Ryan, make sure the wheel openings are large enough and the tires are strong enough, this airplane will want to tip over because of the wheels rubbing the pants, this happened to me two years in a row at the Nats. This airplane is one great looken bird in the air, I fell in love with the Ryan when Maxey Hester won first place at the worlds in the 1960's. Have fun, that's the main thing.
Blessings
Allen