The Murphy Builders Site

The pitot is a closed system. There isn't any airflow through it.

----- Original Message -----
From: "Jay Yau" <jayyau28@hotmail.com>
To: <rebel-builders@dcsol.com>
Sent: Monday, April 12, 2010 8:10 AM
Subject: [rebel-builders] pitot tube drain

Any one has Airspeed indicator fail when flying in wet country? like to
get a advise for a pitot tube water drain?



Jay


_________________________________________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with
Hotmail.
http://www.windowslive.com/campaign/the ... P:042010_4



-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

Normally when installing a pitot line, one installs a T
in the line with a plug in the downward plugged end of
the T so that water will collect there
before draining to the instruments. The plug has to have a
good seal as the pitot system is a closed system. However, if
water gets into the pitot system you want to catch it in the T
before it eventually drains to the instrument (if your pitot is
mounted higher than the instrument). Removing the drain plug
allows you to drain any collected water.

-----Original Message-----
From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf Of Bob
Palmer
Sent: Monday, April 12, 2010 12:20 PM
To: rebel-builders@dcsol.com
Subject: Re: [rebel-builders] pitot tube drain

The pitot is a closed system. There isn't any airflow through it.

----- Original Message -----
From: "Jay Yau" <jayyau28@hotmail.com>
To: <rebel-builders@dcsol.com>
Sent: Monday, April 12, 2010 8:10 AM
Subject: [rebel-builders] pitot tube drain

Any one has Airspeed indicator fail when flying in wet country? like to
get a advise for a pitot tube water drain?



Jay


_________________________________________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with
Hotmail.

http://www.windowslive.com/campaign/the ... cid=PID283
26::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4

-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------






-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

What Bob said! In flight there isn't any air flow into the tube.. just
variable air pressure.

Depending on where you put the pitot though... when the aircraft is sitting
on the field, in the rain (and condensation), water does find it's way in on
some systems. For that reason I generally put a tee and drop tube with a
plug in it, in the low spot of the pitot line. This lets any moisture
collect where it is easily drained IF necessary and won't effect the A/S
function.

I found this out the hard way.... while at Osh '95 with my Rebel, my A/S had
water in it and I left and flew home without one.

Wayne

----- Original Message -----
From: "Bob Palmer" <rtpalmer@shaw.ca>
To: <rebel-builders@dcsol.com>
Sent: Monday, April 12, 2010 12:20 PM
Subject: Re: [rebel-builders] pitot tube drain

The pitot is a closed system. There isn't any airflow through it.

----- Original Message -----
From: "Jay Yau" <jayyau28@hotmail.com>
To: <rebel-builders@dcsol.com>
Sent: Monday, April 12, 2010 8:10 AM
Subject: [rebel-builders] pitot tube drain

Any one has Airspeed indicator fail when flying in wet country? like to
get a advise for a pitot tube water drain?



Jay


_________________________________________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with
Hotmail.
http://www.windowslive.com/campaign/the ... P:042010_4



-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

My "L" shaped pitot tube under the wing has a 1.5-2 deg negative slope,
along with a rather nigh vertical section running up into the wing, so even
rain water blowing while on the ground will drain in flight attitude.
Condensation is still a potential source of moisture.

I have a "T" in the pitot line at the bottom of the strut, before entering
the cockpit. One 90 deg. side of the "T" makes the necessary turn up to the
cockpit, and the other is capped as a collector/drain. See photo at
http://n254mr.com/node/557

Ron
254R




-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

Ron,



Your picture tells everything, thanks!



Jay

From: rshannon@cruzcom.com
Date: Mon, 12 Apr 2010 09:56:25 -0700
Subject: Re: [rebel-builders] pitot tube drain
To: rebel-builders@dcsol.com

My "L" shaped pitot tube under the wing has a 1.5-2 deg negative slope,
along with a rather nigh vertical section running up into the wing, so even
rain water blowing while on the ground will drain in flight attitude.
Condensation is still a potential source of moisture.

I have a "T" in the pitot line at the bottom of the strut, before entering
the cockpit. One 90 deg. side of the "T" makes the necessary turn up to the
cockpit, and the other is capped as a collector/drain. See photo at
http://n254mr.com/node/557

Ron
254R




-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

_________________________________________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with Hotmail.
http://www.windowslive.com/campaign/the ... P:042010_4



-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------