ORIGINAL: buzzard bait
Looks like it would actually be ideal on somewhat larger models (for Aeronca types I guess about 30 to 35 inches, built light, right?).
Jim --
For a 24" model, the 10 gr. motor should work, providing it's light. For an Aeronca in the size range you mentioned, you might want to consider a little larger motor.
motor, $9.95:
http://www.hobbycity.com/hobbycity/s...idProduct=2069
battery, $8.99:
http://www.unitedhobbies.com/UNITEDH...idProduct=5477
servo, $3.65:
http://www.hobbycity.com/hobbycity/s...?idProduct=662
The motor weights 24g, servos are 9g (equivalent to the HS-55), and the battery is 51g (1000 mAh).
The 10A ESC will work with this motor. I've used this combination on a 36" flying wing and foam planes in the range of 19" to 33".
I've also used [link=http://stores.ebay.com/Heads-Up-RC]Heads Up RC[/link] with good service. If you will visit this site, choose a motor, then scroll to the bottom of the page, he has included a lot of information that may be quickly and easily read.
Hobby City/United Hobbies has good pricing, but ship times will run about 3 weeks and shipping can be expensive if much weight is involved. Do not order an item that is out of stock.
Unless the motor ships with it, you will need a mount, prop saver and bullet connectors. You may also need connectors for the ESC and a charger capable of handling Li-Po's.