"Peter Duniho" wrote in message
...
"Dan Luke" wrote in message
...
Sorry, Pete; you fly a ...?

Lake Renegade (turbocharged model).

Did you happen to look at the tach or MAP during any of these events?

No. Of course, in hindsight that might have provided useful information.
But even when the takeoff is going smoothly, I'm a "eyes outside" kind of
person (once the proper reading of the gauges has been confirmed during
the
takeoff roll, of course).

In this particular situation, my mind was focused on where on the water
would be acceptable for a landing (though, frankly, the Tacoma Narrows are
not generally amenable to seaplane landings in any case, due to strong
currents through there), and on a possible landing back at TIW.

Maybe I could have had my front-seat passenger watch the gauges, to try to
correlate them with the noise. But I personally didn't have the attention
to spare. I would have either have had to keep my eyes on the engine
gauges
until the noise occurred, or I would have had to hope to be able to shift
my
attention quickly enough to evaluate the gauges in the short period during
which the sound occurred. Neither would have been practical to do, IMHO.

It's a pretty good argument for a data-recording engine monitor. I'll
have to think about getting one of those.

Pete

Any idea of what your passengers were doing at the time. In my airplane (an
RV-6) there is a noticable change in the tone and volume of cockpit noise
(and vibration) either the pilot or passenger shifts his/her feet on the
floor. I know when I move my feet, so it doesn't surprise me, but when I've
got a "shifty" passenger, s/he will put me on edge for a few seconds here
and there.

Getting back to your situation, is it possible that a passenger found a neat
way to rest a hand/arm/foot/etc. that created an unusual resonance? I
realize this wouldn't have caused a power loss.

One other thing to consider is a stuck valve. Your description sounds
similar to my understanding of the symptoms of a stuck valve.

KB