Originally Posted by JSF-TC

One key difference from a house/ car is that we can't pull over and stop to sort it out...........

We have so many single point failure cases in every one of our models we can't protect them from all scenarios.

We have dual batteries and dual Rx's that help, but in most cases we don't have dual independent servo's and linkages on every critical surface. If we do (giant scale 3D is probably the most prevalent use of multi-servo surfaces), they are rarely truly independent and are mainly for torque requirements and stability on long/ flexible surfaces, rather than for flight critical redundancy.

Setting up dual servos that don't fight each other is complicated and just having 2 servos on a surface with perfect servo matching doesn't protect from a jammed servo - see recent CARF Hawk thread for a way to decouple the servos to offer some protection.

Flying our models, especially unproven scratch-built projects is a balance of risk. Having been bitten I know how I'm revising my next build, and that is to avoid poly-fuses. Once the design is proven with actual current draw data across the full envelope I may change my mind.


Paul