Hi Gilles,
>> Do you really advise here to get rid of a safety feature?
> Not all aircraft rely on spring tension to open the throttle against the
> friction in the outer case. Some have a push-pull cable and the throttle
> valve will stay where it is, should the control fail.
We are talking about the Rotax engine, and the Europa. In the Rotax
documentation it is quite clear, why the spring is there and that the
spring should be able to pull the cable. Rotax even offers two methods for
improvent if the supplied spring is not strong enough. Removing the spring
is not one of them. If the valve remains shut on final, when you would
like to compensate for a stronger then estimated head wind you will
discover the reason.
> Hundreds of MCRs have been flying for years with a piano wire to replace
> the stranded cable and spring, without any problem whatsoever. The
> linkage is far far safer with a push-pull control than with a flimsy
> stranded cable and puny spring. You can even keep the spring for your
> peace of mind !
A solid wire is per definition more prone to breaking. In a Europa, that
wire has to go around corners, it can not be straight. Therefore, in a
Europa, where this list/forum is about, it will break sooner then a
stranded cable, especially if routed wrong in the first place. If you
think the factory supplied throttle cable is flimsy, i suggest to try to
break it. By hand. I guess you need about 600 kg of pulling force. I
can't take remarks like that very serious. Advising to remove safety
components on the other hand is very serious business.
> natural sweeps instead of turns. The usual place for breaking a cable is
> at a wrongly rigged portion between throttle lever and cable case. So a
> careful design of this portion, and some provision for pivoting is key.
Again, it's all in the manual, this case the Europa Builders Manual. Have
you ever looked at it?
Regards,
Jos Okhuijsen
--
workshopcam http://www.okhuijsen.org/plane
http://www.europaowners.org/kit600
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