Re: A Braced EZB Challenge: Fun, Glory, and $$

From: Yuan Kang Lee <ykleetx_at_gmail.com>
Date: Sun, 09 Sep 2012 22:33:21 -0000

--- In Indoor_Construction_at_yahoogroups.com, "Mark F1diddler" <f1diddler@...> wrote:
>
> Kang, Your incentive program sure is attractive! I hope your
> challenge reinvigorates ezb. I'll probably give it a try after
> I overhaul my F1d fleet.

Thanks, Mark. The challenge ends September, 2013, so there is time after Team Selection to take it. I hope you take a trip to Lakehurst to get that 30-minute flight. Of course, you could also do it at Kibbie or Johnson City.

> I'm wondering how much motorstick mass an external wood brace could > replace? Probably not a massive amount due to opposite stab twist,
> which is partly why rolled tubes (torsion resistance) go along so
> nicely with external (wire) bracing. But maybe there will be
> suitable work-arounds for opposite stab tilt.

The intent is to use a "normal" motorstick that is strengthened by wood bracing. I'm going after simplicity. The idea is so that fliers can put their minds on the *other* things that are required to fly an EZB well. I will be more specific in the wording of the bracing requirement.

Here's the rundown on torsional stiffness. If you use a prop does not flare and can produce a lot of thrust under high torque, the EZB will climb very steeply if the motor stick is not bowed. Will opposite stab prevent the model from turning and cause it to stall/crab? it will depend on the overall trim of your model -- amount of nose-up trim and amount of left thrust used. You guys will have to find out.


If you use a flaring prop, the prop may be stalled at launch and will not produce enough thrust for a steep climb. A flaring prop and a bowed motor stick is a bad combination. On my light models, this means racing around in a flat circle with an imminent dive to the ground. My guess is that a braced motor stick will prevent the model from diving to the ground. But I'm not sure what the model will do when it has excessive inboard wash-in, excessive opposite stab tilt, and a flaring prop.
Received on Sun Sep 09 2012 - 15:33:22 CEST