See page 318+ in "Helicopter Maintenance Manual"

See page 268+ in "The Sportplane Builder"

Don't bother to see chapter 14 in "Aircraft Inspection and Repair"

See Photo 142 etc. "UltraSport 254 Construction Manual"

Consider using tank design as noted on sketch paper, dated Oct 4, in folder. Put divider in lower portion of tank so that the engines will not stop at same time?

 Consider mounting fuel tank high on back of seat.

Advantages

Gravity feed

Visual fuel gauge at side of seat

Disadvantages

Sitting just about above the 'hot' engines.

Can fuel be separated from engines by firewall?

1 gallon = 231 cubic inches 1 gallon = .13368 cubic feet

5 gallons = 1155 cubic inches 5 gallons = .6684 cubic feet

The aluminum tank in Spruce catalog is made of 5052 aluminum with a thickness of .040". Spruce offer 5052H-32 aluminum sheet for fuel tanks.

 See p. 109 in "Fiberglass & Composite Materials"

 Consider fuel cell, for shock absorption on hard landing?

1 US gallon of fuel weights 6.011 pounds, there for the fuel in a 5 US gallon tank will weight 30 pounds.

Ref: 1 liter = 0.228 Imperial gallon

1 liter = 0.264 US gallon

1 pounds = 0.630 liters

1 liter = 1.587 pounds

Re: the weight of gasoline in relation to the weight of water. Gas floats on water so it is lighter; F&L Fuel has a density of .721 lb/gal. The important thing is to always use the same density fuel. Changing fuels can richen or lean an engine. Good race fuels never change their density. Fuel density is kind of like oil viscosity. Heavier weights flow less volume through a given opening. This is the same with gasoline; change the density and you can flow less or more through the same carburetor jet.

Make tank out of composite at top back of seat. The "box" will add strength to the composite frame.

A manual says that the fuel in a gravity feed system should be 1-1/2 to 2 psi (60 to 80") above the carburetor. The bottom of the fuel tank on the Bell 47 is only 21" above the carburetor.

'Two-Stroke Performance Tuning' P.115 says that the pressure of gravity feed should be less than 1 psi.

All carburetors should probably be at approximately the same elevation.

I think line(s) must be large enough to test drain tank in 30 minutes or less.

Consider setting and connecting removable auxiliary tank on to of standard tank.

If the 2 engines burn 1155 cubic inches in one hour then 5 minutes of flying on 1 engine will require (1155/(2 * (60/5))) = 50 cubic inches (1 quart)

The Robinson R-22 has both a fuel quantity sender & a gauge plus a low fuel switch and light.

Consider using the loss of pressure from the engine that runs the fuel pump to indicate that an engine has quite. The pressure from the running engine could tip the extra fuel into the fuel tank. IE as long as the pressure from both engines is balanced (a spring could help hold a netural position) the extra will not be pored in,

Locate in lowest point in system. To drain water.

Must be within reach of pilot.

Is required.

Is it possible to have both of the fuel pumps deliver fuel to both the engines? This way if one pump goes down the other will still feed both engines, if it has the capacity. Mikuni carburetor has its own built-in fuel pump.

Ton comply with full certification each engine must have a separate fuel system of pumps and lines.