fuel vent location flying 6

[jim]

Hi,

I am preparing to change out the old aluminum gear leg fairings and intersection fairings with new fiberglass on the 6. I have the upper intersection fairings from fairings etc. The upper intersection fairings want to set right over the fuel tank vents as they are currently installed.

Does anyone have any good reasons not to move this vent on the belly? I did a search and there was a thread where the rocket guys were venting from the bottom of the inboard tank ribs which looked interesting, but even was thinking to move the hole more towards the middle and possibly back a little to clear the intersection fairing. Any comments or concerns?

Thanks in advance,

[pierre smith]

Hi Jim,
No reason not to move them. Just be sure they don't get too far inboard to where your feet or heels can kick the lines. Just keep them near the firewall.

Regards,

[Mel]

I went to the "Rocket" fairings on my -6 when I changed to the "Dolly Parton" wheel pants. I just moved the vents about an inch inboard from where they were.

[Kyle Boatright]

I cut holes in my upper fairings for the vents (which are located in the standard position). I didn't want to cut any unnecessary holes in my airplane.

[jim]

Pierre, Mel, and Kyle,

Thanks for the reassurance. I think I'll move them inboard and back a little and then plug the holes. There should be plenty of room to clear the rudder pedals. Seems logical to me.

I have considered doing what the rocket guys do with putting the vent on the bottom of the tank skin inboard and using 2 or 3 coils of tubing, but am concerned about the "possible" siphon phenomenon as mentioned in the thread I read. However, then I would have 4 holes to plug. I didn't see where anyone actually had a problem with siphoning happening, but I only want to do this once and not have to move it again or plug more holes!

Kyle, I thought about doing that but the vent is so far to the edge that I would really have to remove a lot of the fairing to clear the vent. Then I started to worry about possibly altering pressures in the vent. Also, when fuel does vent it could end up going down the inside of the fairing unless I take out a large amount of the fairing to clear the entire thing. Seems in this particular installation to not really be the way I want to go. I think it will make more sense just to move the vent.

Thanks again,

[N24YW]

You will be doing a lot of glassing to make the fit of the upper fairings. I went ahead and just put a bump in the fairing and then drilled a hole in it. I believe it makes the plane at least .001 knots fast not haveing the vent hanging out.

Jim Knight Burlington Iowa

[jim]

Jim,

I hadn't really thought about that 0.001 kt improvement in speed by fairing the vent. Now I gotta rethink the whole thing again! :

Thanks,