Bob Harrison wrote:
>
> Hi! Fred.
> Just browsing through one or two saved messages arrived back with this one
> and it occurs to me that you are still working on 350# as per PRE the "
> increased bungee size mod. My mod instructions uplift the break weight to
> 400lbs to 500lbs with engine fitted. This means a lever applied to uplift
> the tail to effect the test down on the nose wheel. When I said I pulled
> down on the prop. it must have been when the break weight was 350 lbs.
> Sorry to "rabbit " on about this but prefer to know you are on the safe side
Do rabbit on, Bob, except saying that here that could alarm the
ladies!
I have don't have that mod. I was just about to post re how 1/2"
bungee, and hooks instead of knots, may solve your your crowding and
thus chafing problems. That'll take another loop, and I don't know
how neat it will be and still avoid overlaps. I may actually have
400#. It was stretched at 145%, and it didn't seem it should be
subjected to more (one catalog says 140%). I have her apart anyway to
take care of those pesky V's that pinch the cord, maybe flox something
in there to widen the V.
If you do corner Europa, let me us what you learn. I am more
confused. I don't see what's wrong with occasional bungee exercise in
abnormal landing/taxing situations, as long as it doesn't chafe. Some
are designed that way I thought. As it approaches the 2" to whack the
safety cable, it takes lots of force, seemed to me. 500# is a narrow
margin against Rob Houseman's computed 700# yield strength of the gear
leg, and the caster angle of the fork could narrow that, and bend the
leg down up front. Is that what happened to you? Maybe the leg could
indeed yield before the safety limit is reached, due to sharply
increasing bungee tension.
Lever on the tail? Does that mean measure the lever arm, weigh the
nose, do the math, and apply the difference? Is that accurate w/o a
gorilla sitting on top of the fuselage fulcrum point? Especially w/o
wings installed.
Regards,
Fred F., A063
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