"Jay Honeck" wrote in message
news:7kLKe.239817$x96.9166@attbi_s72...

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After a few more seconds of debate, I ended the discussion by pushing my
yoke firmly forward, inducing negative G and allowing us to pass
harmlessly beneath the traffic. We cleared the plane with room to spare.

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However, I did (and still) wonder about putting that much negative-G on
our 34 year old airframe. Without a G meter it's impossible to know how
much G was induced, but I'd say it was 50% more than I've ever done
before. (The only negative G maneuver I ever do is the push-over at the
top of a steep pull-up, known by my kids as an "Up-Down".) Was 50% more
too much?

We were climbing out, so our airspeed was relatively low -- probably
around 80 knots. The entire maneuver lasted less than 5 seconds, and
nothing floated in the cockpit -- but in an old airplane, how much is too
much?

As another reference point (and a crude way of measuring the negative Gs),
I routinely read about guys doing the "up-down" maneuver to the point
where their engine sputters due to fuel starvation. I've *never* done the
maneuver to that degree, even in this situation (although that may be due
to the short duration of the maneuver) -- so I'm assuming that I didn't
push the airframe beyond structural limits. Since that flight I've
carefully inspected the empennage, and there is obviously no visible
stress or strain, or I wouldn't be flying it -- but how can you really
know without extensive metallurgic testing?

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Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Is the engine on the pathfinder carburated? If so, the engine will stumble
anywhere near zero g. In addition, since you didn't see anything "flying"
inside the cockpit, my guess is that you merely approached zero g, which
isn't a problem at all.

KB