Pinging Ron Wanttaja - "Unporting?"

Bob Chilcoat wrote:
Ron,

I posted this over on RAP but apparently managed to stump everyone. I
thought that perhaps some of your contacts at Boeing might know if this
word, "unporting" was misused by Gann, or is an old term that is no longer
used. It just doesn't sound right to me.

Before Ron provides you the right answer, let me offer what is probably
a wrong one. This is what the internet is all about...wild ass guessing
at it's finest.

"Unporting is the balance destruction of the elevators by aerodynamic
force. I won't confuse you with theory, but if enough separation between
the fixed and the balance portion of your elevators occurs, your airplane
will go into a vertical dive or even beyond the vertical, and no two men in
the world are strong enough to bring it out. This can be caused by a
missing hinge bolt."

I'm guessing that it has something to do with the flow of air between
the top (high pressure) side of the elevator and the bottom through the
gap between the fixed and movable pieces, which for certain geometries
and separation can enter an unstable mode (flutter).

How close am I?

On Mon, 22 Nov 2004 15:30:55 -0500, nafod40 wrote:

Bob Chilcoat wrote:
Ron,

I posted this over on RAP but apparently managed to stump everyone. I
thought that perhaps some of your contacts at Boeing might know if this
word, "unporting" was misused by Gann, or is an old term that is no longer
used. It just doesn't sound right to me.

Before Ron provides you the right answer, let me offer what is probably
a wrong one. This is what the internet is all about...wild ass guessing
at it's finest.

I'm guessing that it has something to do with the flow of air between
the top (high pressure) side of the elevator and the bottom through the
gap between the fixed and movable pieces, which for certain geometries
and separation can enter an unstable mode (flutter).

I'm afraid this one is well out of my area of expertise, but I think your
explanation is what was going on. Perhaps the slight geometric change due to
the missing bolt allowing air to leak from top to bottom and trigger flutter at
an unexpected aerodynamic condition.

But calling it "unporting"? I've always heard that term used to describe a
condition where fuel inlets get the gas sloshed away so they suck air.

My money's on Nauga to explain this one....

Ron Wanttaja

Ron Wanttaja wrote...

My money's on Nauga to explain this one....

Last time Bob asked this I think I wrote that he might have
meant "uncorking," which is sometimes used to refer to a
departure from controlled flight. Or maybe Gann just made
something up. Somebody dig him up and ask him.

Dave 'colloquial' Hyde