fuel pick ups

A forum in which to discuss topics specific to the assembly of the RV 7/7A.
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stevewiz
Class E
Posts: 63
Joined: Thu Sep 19, 2013 3:37 pm
Location: appleton,wisconsin

fuel pick ups

Post by stevewiz »

Quick question, We are building the fuel tanks and I am wondering if we need to build the “inverted fuel line pick up option” or just go with the standard vans fuel pick ups. Our goal is not long inverted flights but will do rolls or loops. Thanks
RV-7 N71SW reserved
Started on 10/8/2013
Working on Fuselage as of 5/10/15 95%done
started finish kit on 7/1/16
engine on order from Barett.Will be shown at their EAA booth and then delivered to us after show

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bullojm1
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Post by bullojm1 »

Steve,

On if you plan to do sustained inverted flight will you need the flop tubes. This means you will also need a fuel injected engine and also an inverted oil system. For positive G maneuvers (Loops, Aileron Rolls, Hammerheads, Barrel Rolls, etc..) the standard pickups are all you need. It's what I use. Furthermore, the inverted tubes stiffen over time and have to be replaced every few years. Another reason my vote is against them if not 100% needed.
Mike Bullock
http://www.rvplane.com
RV-7 | Superior IO-360 | Whirlwind 200RV
Garmin GTN650 | GRT Dual Sport SX EFIS
Status: FLYING!

stevewiz
Class E
Posts: 63
Joined: Thu Sep 19, 2013 3:37 pm
Location: appleton,wisconsin

Post by stevewiz »

Thanks Mike that's what we needed to hear. On a second note sorry we missed your plane at EAA. We searched on Friday early PM but could not locate you.
RV-7 N71SW reserved
Started on 10/8/2013
Working on Fuselage as of 5/10/15 95%done
started finish kit on 7/1/16
engine on order from Barett.Will be shown at their EAA booth and then delivered to us after show

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captain_john
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Joined: Sun Oct 31, 2004 9:17 am
Location: KPYM

Post by captain_john »

Steve, Mike is rather elusive. He mighr appear at the strangest places at the most unusual times. As far as your pick up tubes go, I installed one in my left tank only. My intention was to use this tank whenever I was horsing around. I do not have inverted oil, but My thought that I did not want to come unported at an inopportune time.

8) CJ
RV-7
Garmin G3X with VP-X & a TMX-IO-360 with G3i
It's all over but the flying! 800+ hours in only 3 years!

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painless
Class C
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Joined: Sun Mar 06, 2005 12:42 pm
Location: Peshtigo, Wisconsin

Post by painless »

Unported CJ? I thought you preferred India Pale Ale?? :mrgreen: :drink:
Jeff Orear
RV6A N782P
Hatz Classic, Welding fuselage
Hatz build log. https://eaabuilderslog.org/?blproject&p ... GNCwv&sid=
Peshtigo, WI

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bullojm1
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Post by bullojm1 »

stevewiz wrote:On a second note sorry we missed your plane at EAA. We searched on Friday early PM but could not locate you.
Steve,

We headed out Friday around 1pm to beat some of the weather that looked like it was headed towards Oshkosh.
captain_john wrote: My intention was to use this tank whenever I was horsing around.
I horse around plenty in my RV and have never had the engine sputter because of lack of fuel. Slight loss of oil pressure is another thing! The oil will depart from a location in the sump that the oil pump can pick it up well before the fuel in the lines will run out. Basic volume measurements - An estimated 10' of 3/8" OD Tubing (assume 1/4" interior diameter) will hold 0.105 gallons of fuel. Assuming your engine will be running at about 25 squared, consuming 12 GPH (or 0.2 gallons per minute). So you have 30 seconds of being in negative G's before the fuel runs out of the lines. And this is being conservative since the fuel filter typically holds a descent amount of fuel.
Mike Bullock
http://www.rvplane.com
RV-7 | Superior IO-360 | Whirlwind 200RV
Garmin GTN650 | GRT Dual Sport SX EFIS
Status: FLYING!

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