Hey Wendell,
now up front my customary warning:
All I post is copied/theory/"what I would do"/no personal experience - worth what you paid for!
b) Okay, it's the little brother (or actually daddy?), but the systems should be similar?
c) With reference to the article above, I would make a 5--8 gallon alu or plastic tank, somewhere below the wing level - under the rear seats as Bill's system or if you don't like the idea, at the lowest part behind the firewall, but somewhere where the mains can drain into easily, 1/2" lines.
I always promote "heavy" fuel lines, never less than 1/2", helps a lot to prevent vaporlock, air bubble lock - after running the tanks dry. An air bubble will have a hard time to block a 1/2" line...
I'd prefer alu for the tank, as it is easier to do fuel plumbing, like in-tank fuel pumps.
Obviously the Cozy (or most Canards) are not real low wing aircraft, but rather midwings, so creating a system that can drain into one common sump should be possible.
Make the tank round or V-shaped at the bottom and you should be able to run it nearly dry (less then 1 gal unusable...).
d) If you copy Bill's system you only need 2 shut-offs, that stay open except for maintenance purpose and 1 single shut-off at the firewall.
e) Return to the 5-8 gal header/sump should keep the temps in control or if you prefer to anyone of the wingtanks, as they are normally open and connected it will balance fine until very low - then watch the ball! FLy a little left/right to empty the wingtanks and land on the 5-8 in the sump! :)
f) One difference I would make is to lead ALL ventlines into one common manifold at the highest point possible (behind the rear seat headrests or just behind there on the firewall) and vent this manifold to some static area (mainwheel fairing?). Just make sure your filler caps are airtight.
g) This way you only need 2 fuel pumps in parallel - you are truly redundant, no fussing around with fuel-selectors (except for after shutdown, if you care for - as your engine is at or above the general fuel level, there should be no real reason to shut off fuel every time....)
Best Regards,
TJ
On 8/30/07, Wendell Voto <jwvoto@itlnet.net> wrote:
Subject: [FlyRotary] Re: need help
TJ,
Sorry about the delay in responding, have been away doing my contract work (still a necessity). I am building a Cozy. Bought a project that I thought was a Cozy MKIV but was one of the very first, other than Nats, 4 place Cozys. It is narrower in the front by about 3 inches (original Cozy 3 dimensions) but is about the same in other repects except the firewall is about 2 inches closer to the landing gear bulkhead than the new plans versions. Don't know how that will effect cg.
Have been thinking more about the fuel system and want the finalize it soon. I put in returns in both tanks and feel I will go ahead and use them and build the header tank slightly smaller than the 15 inches mentioned earlier. Will use 2 outside the tank pumps so no switching will be needed.
Wendell
Wendell,
would you please remind me what airplane you are building?
TJ
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