The Murphy Builders Site

Posted: **Sat Feb 18, 2012 8:52 am**

Hi Guys

We are at the point to get serious about installing the plumbing for the
pitot/static and I am trying to figure out what size (ID) of line to run to the
pitot and static ports. I have seen some references to 1/4" tubing but the
orifice of both the static fitting which attaches to the side of the fuselage and
the pitot are not large, perhaps .125 for the pitot, smaller for the static and I
don't expect there is much flow to speak of so is there any good reason for the
1/4" tubing?

I was thinking about more like 1/8" ID in a polyurethane which would be light,
small and with the PU, impervious to just about anything (including our present
cold snap....but thats' another story).

Any thoughts? Would the 1/8" be too small?

Thanks

Dave
elite583.cjb.net
--
David A. Ricker
Fall River, Nova Scotia
Canada

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
https://www.dcsol.com/public/code/html-subscribe.wcx
Archives located at https://rebel:builder@www.dcsol.com/default.htm
To contact the list admin, e-mail 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
-----------------------------------------------------------------

Posted: **Sat Feb 18, 2012 8:52 am**

Bigger is better here Dave for loss of pressure over distance of pipe.
Although there is no actual air flow it still seems to work better with a
larger line. Certified airplanes generally have 1/4" alum line run through
them with rubber joiners at detach points. I would be afraid that if you
just used 1/8" line you would be VERY susceptible to freezing in the line
from any minor amounts of moisture. I generally use the same 1/4" Parker
parflex tube that MAM supplies for the brake lines. Seems to do the trick.

Cheers,
Wayne

----- Original Message -----
From: "David Ricker" <ricker@inherentsys.ca>
To: <murphy-rebel@dcsol.com>
Sent: Saturday, January 10, 2004 4:27 PM
Subject: Pitot Line Size?

Hi Guys

We are at the point to get serious about installing the plumbing for the
pitot/static and I am trying to figure out what size (ID) of line to run

to the

pitot and static ports. I have seen some references to 1/4" tubing but

the

orifice of both the static fitting which attaches to the side of the

fuselage and

the pitot are not large, perhaps .125 for the pitot, smaller for the

static and I

don't expect there is much flow to speak of so is there any good reason

for the

1/4" tubing?

I was thinking about more like 1/8" ID in a polyurethane which would be

light,

small and with the PU, impervious to just about anything (including our

present

cold snap....but thats' another story).

Any thoughts? Would the 1/8" be too small?

Thanks

Dave
elite583.cjb.net
--
David A. Ricker
Fall River, Nova Scotia
Canada

*-------------------------------------------------------------------------*

To unsubscribe from this list go to:
https://www.dcsol.com/public/code/html-subscribe.wcx
Archives located at https://rebel:builder@www.dcsol.com/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com

*-------------------------------------------------------------------------*

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
https://www.dcsol.com/public/code/html-subscribe.wcx
Archives located at https://rebel:builder@www.dcsol.com/default.htm
To contact the list admin, e-mail 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
-----------------------------------------------------------------

Posted: **Sat Feb 18, 2012 8:52 am**

Hi Guys

The pressure loss thing was exactly what I was thinking about but I couldn't
see how there would be much flow. Having said that I now can think of another
good reason to go with a larger and aluminum line and that is to make sure any
moisture will run down hill (wing dihedral) and not collect in the inevitable
dips that would form in any flexible lines and this time of the year freeze.
Think I will have another look at where I can put some solid lines.

I'll keep Ralph's suggestion about traps in static port locations in mind also.

Thanks

Dave R

"Wayne G. O'Shea" wrote:

Bigger is better here Dave for loss of pressure over distance of pipe.
Although there is no actual air flow it still seems to work better with a
larger line. Certified airplanes generally have 1/4" alum line run through
them with rubber joiners at detach points. I would be afraid that if you
just used 1/8" line you would be VERY susceptible to freezing in the line
from any minor amounts of moisture. I generally use the same 1/4" Parker
parflex tube that MAM supplies for the brake lines. Seems to do the trick.

Cheers,
Wayne

----- Original Message -----
From: "David Ricker" <ricker@inherentsys.ca>
To: <murphy-rebel@dcsol.com>
Sent: Saturday, January 10, 2004 4:27 PM
Subject: Pitot Line Size?

Hi Guys

We are at the point to get serious about installing the plumbing for the
pitot/static and I am trying to figure out what size (ID) of line to run
to the
pitot and static ports. I have seen some references to 1/4" tubing but
the
orifice of both the static fitting which attaches to the side of the
fuselage and
the pitot are not large, perhaps .125 for the pitot, smaller for the
static and I
don't expect there is much flow to speak of so is there any good reason
for the
1/4" tubing?

I was thinking about more like 1/8" ID in a polyurethane which would be
light,
small and with the PU, impervious to just about anything (including our
present
cold snap....but thats' another story).

Any thoughts? Would the 1/8" be too small?

Thanks

Dave
elite583.cjb.net
--
David A. Ricker
Fall River, Nova Scotia
Canada

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
https://www.dcsol.com/public/code/html-subscribe.wcx
Archives located at https://rebel:builder@www.dcsol.com/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com

*-------------------------------------------------------------------------*

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
https://www.dcsol.com/public/code/html-subscribe.wcx
Archives located at https://rebel:builder@www.dcsol.com/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*

--
David A. Ricker
Fall River, Nova Scotia
Canada

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
https://www.dcsol.com/public/code/html-subscribe.wcx
Archives located at https://rebel:builder@www.dcsol.com/default.htm
To contact the list admin, e-mail 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
-----------------------------------------------------------------