>If keeping a few grams out from around the servo holes >improves yaw inertia by 5% then how can loading your >tube spar with ounces ballast be a real benefit?
First of all, the contribution of any added weight to the inertia depends on the square of the distance of the added weight from the CG. So adding mass at the tips is 4x worse than adding mass halfway out. Here's how much 10g of added mass (5g on each side) adds to the percentagewise inertia of a 60 oz Supra, versus spanwise position of the added mass: y=67": +4.0% at tip y=36": +1.1% at outer servo y=10": +0.1% at inner servo Second of all, what really matters for handling quality is not the inertia, but the inertia/mass ratio. This makes adding mass near the center even less consequential. Here are the effects of the 10g mass on the inertia/mass ratio: y=67": +3.4% at tip y=36": +0.6% at outer servo y=10": -0.5% at inner servo So adding mass near the tips is still quite bad. But adding mass near the center (inner servos, wing ballast, etc) actually makes things better, not worse. RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
