Long-Range Fuel Tanks

 

Date:   May 2004 - September 2004

Supplement

Section:    Long Range Fuel Tanks

 

Long-Range Fuel Tanks

Since we got a slightly smaller total fuel capacity than we expected in the strakes, we've elected to prepare supplemental fuel tanks.  The strakes built with a baggage area are advertised as holding 35 gallons a side.  However, we have found that ours hold just over 30.  This could be due to slight differences in bulkhead placement (although we've checked that fairly carefully), or because we used quite a bit of Jeffco to assure that our tanks didn't leak.  Net, this makes Houston (one of our primary destinations) a bit a stretch for a non-stop IFR flight (with the longer 45 minute fuel reserve requirement).  To deal with this, we intend to build two removable storage tanks of 10-15 gallons a side.  This will allow us to cover the window in the strake and pop in the reserve fuel tank.  These tanks will be made with quick disconnect at the very top and bottom edge of the rear of the tank, which will allow them to fill and vent just as if they were built integral to the tank from the start with minimal leakage when connecting or disconnecting.  This will be especially nice since we can choose to use one side for fuel and one for baggage, or whatever combination suits the flight best.

The strake cutout was covered with plastic, and then closed up with a piece of cardboard so that the expanding foam would take the strake shape.  This plug will then be covered with a release agent (duct tape) and then covered with BID to create the tank.

Filling the Strake Void

Finished Plug Pilot-Side

Strake Plug Formed, Co-Pilot Side

Aftermath of Creating Foam Plugs

 

~  End of Chapter ~ End of Section   ~

04/04/2010    Here I've run new hoses to the shut-off valves, and from the new long-range T connectors to the quick-disconnect fittings (dripless).  I'm really happy with how this turned out, and it should give us total flexibility on baggage versus fuel capacity, and when the long range tanks are in, they should fill and drain just like they were built with the strakes.  We'll leak test all of this later this week, and strain the fuel system off contaminates.

New hoses to sump and QD connections

04/03/2010    Here I've run new tubing at the same elevation as the existing strake vents and drains (top and bottom of the center spar) for the new connections to the long-range quick disconnect fittings.  Because of this, the long range tanks should fill and drain just like they were buildt as an integral part of the strake.  We come down from the existing cross to a T for the vents, which are braced with angle aluminum structuraled to the spar, with an adel clamp to secure it to each.  For the drains, I changed the system to put a T in front of my maintainence shut off valves so the long range tanks can be shut off as well, and then we'll run new hose to the sump.  The quick disconnects are dripless from Jegs

New vent cross down to new T

Vent quick disconnect (dripless)

New drain T and relocated shut off