] Marv, Verrrrry interrrrresting. Not. You calculated the 1/4" tubing speed at .95 Kts (1.1 mph or 2938 furlongs/fortnight). I don't see water flowing against gravity with that little of a push. I am sure some engineer can calculate those forces. What, me worry? I only pump 5 gallons per hour out of each wing. But then, it is at a faster rate for a shorter duration (about 1 gal/minute) so the water has time to drip back down in between pump usage. I have never detected water in the fuel - even after several hours in "light" rain at 170 KIAS. I have a mini NACA vent in the belly for the header, that is drawing 10 gallons per hour (water must be lifted 2 feet), and I use 1/4" tubing with bevel cut vents for the wings (vertical run is about 5 inches). Scott Krueger AKA Grayhawk Lancair N92EX IO320 SB 89/96 Aurora, IL (KARR) Darwinian culling phrase: Watch This! ************************************** See what's free at http://www.aol.com. -------------------------------1178745962 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

In a message dated 5/9/2007 3:59:54 P.M. Central Daylight Time,=20 marv@lancair.net writes:

<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>[The=20 area of a 1/4" id tube is about 0.05in^2, so it would take 1155 inches of=20 tubing to hold 57.75cf, which equates to about 96 feet/minute to move that= =20 much volume. Increasing the ID of the vent tube to 3/8" would=20 reduce that velocity by more than 1/2 (its x-sectional area is about=20 0.11in^2. <Marv> ]

Marv,

Verrrrry interrrrresting. Not.

You calculated the 1/4" tubing speed at .95 Kts (1.1 mph or 2938=20 furlongs/fortnight). I don't see water flowing against gravity with th= at=20 little of a push. I am sure some engineer can calculate those forces.=20

What, me worry?

I only pump 5 gallons per hour out of each wing. But then, i= t is=20 at a faster rate for a shorter duration (about 1 gal/minute) so the wat= er=20 has time to drip back down in between pump usage. I have never=20 detected water in the fuel - even after several hours in "light" rain at 170= =20 KIAS. I have a mini NACA vent in the belly for the header, t= hat=20 is drawing 10 gallons per hour (water must be lifted 2 feet), and=20 I use 1/4" tubing with bevel cut vents for the wings (vertical=20 run is about 5 inches).

Scott Krueger=20 AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL=20 (KARR)

Darwinian culling phrase: Watch=20 This!

See what's fr= ee at AOL.com.=

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