Message-ID: <38401340.79A1DE3D@regandesigns.com>
Date: Sat, 27 Nov 1999 09:22:09 -0800
From: Brent Regan <brent@regandesigns.com>
To: Lancair List <lancair.list@olsusa.com>
Subject: Static Water
Mime-Version: 1.0

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The other day we had a patch of blue sky pass overhead (the first in two
weeks) and my thoughts turned to flying. My two sons wanted to go as well so
we preflighted the IV and piled in for a pleasure flight. Just before Vr I
noticed that the airspeed was about 5 Kts fast, the pleasures of winter's
density altitude I thought. On climb out my scan caught the altimeter, VSI
and airspeed needles all jump simultaneously. I leveled off at about 1500
AGL and brought the power back to 18 inches. Holding it level I was
indicating 220 Kts, then suddenly 180 Kts. Not good.

It was obvious from the symptoms. The patient had enough water in its static
system to occlude the line and the needles would jump whenever a bubble
would pass. All the static instruments were affected including VSI,
airspeed, altimeter, encoder, cabin altimeter, AOA and my RMI backup. I
couldn't trust any of them. Even the GPS altitude readout is affected by the
encoder. What was left isn't really needed on a VFR flight. I have two
static ports but no alternate static source (pressurized cabin and all).

OK, here is the plan: proceed to COE, get AWOS, use GPS plus wind component
to estimate airspeed, stay high and hot and follow the ILS to a happy
ending. Why not just land the damn thing? you ask. Well, I believe in using
all available information and I don't like taking any chances in the
pattern.

Only one problem with "The Plan", a message at the end of the AWOS states
that the runway with the ILS (5) is closed. My options are now to either
land on 1 (crosswind, 2000 feet shorter, no ILS) or land on 5 anyway. I
decide I need more information and make a low pass over 5. Everything seems
normal and sometimes the airport manager forgets to change the AWOS message
after they do maintainance, so runway 5 it is. Safety is greater than rules.

After an uneventful landing I taxi over to the fuel island and shut down. I
disconnect the static line under the instrument panel and then I get out and
proceed to suck the water out of the static system. This prompts my 6 year
old to query "Dad, how come you are kissing the airplane?"

After I stop choking I explain what I am doing. I suspect he is not
convinced.

So how did this happen to a pampered, always hangered airplane? Well, since
the last flight, I had the concrete floor in the hanger sealed so I had to
park the bird outside (gasp) overnight. That night was windy with a light
rain. As I mentioned I installed two static ports, one on each side, that
are "T"ed together. The wind must have created a pressure differential
between the ports that sucked in about 10cc of water. The same conditions
have existed at OSH but the colder temperatures here prevented the water
from evaporating.

Check those static lines!!

Compliments of the season.

Brent Regan


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