flyvulcan
Well-Known Member
Hi everyone,
The Lightning Bug kit that my Komet is based on has a fuel pickup point at a low point in the fuselage tank. The fuselage tank is integral to the main structural keel that runs down the centre of the lower fuselage half.
The fuel pickup point can be seen in the following photo. The brick is holding down the seat base for the front seat. The current fuel pickup point can be seen directly below the brick. The drain point is about 4" aft of the pickup point at the lowest point in the tank.
I do not believe that the current pickup point is suitable for my jet engine application. Jets rely on fuel to maintain the flame. If the fuel flow stops even for a short time, so does the flame. I feel that an aerobatic system would be prudent, so that any negative g imposed due to any cause will not cause engine failure.
So my challenge is to incorporate an aerobatic fuel pickup system to replace the existing system. This is where I need hints.
I shall explain the geometry of the fuel tank in order to make the setup as clear as possible to readers.
Around 5" forward of the current fuel pickup point is the foward face of the fuel tank. The nosewheel retracts such that it almost touches the forward face of this bulkhead, so it is not possible to mount a through bulkhead fitting for a flop tube to this bulkhead.
There is also a baffle to be installed around 8" aft of the current pickup point (sorry, no photo of this). This baffle has a flapper valve in its base to allow fuel to move forward to the pickup "collector box" and prevents fuel from flowing aft at nose-high attitudes and low fuel states. The baffle will also have a gap at the top.
So, what are my options for fuel pickup here? The fuel line from the tank will run aft, probably along the side of the structural keel (fuel tank) to the engines which are just aft of the back seat. What Aircraft Spruce (or other) components might be recommended?
Thanks,
Dave
The Lightning Bug kit that my Komet is based on has a fuel pickup point at a low point in the fuselage tank. The fuselage tank is integral to the main structural keel that runs down the centre of the lower fuselage half.
The fuel pickup point can be seen in the following photo. The brick is holding down the seat base for the front seat. The current fuel pickup point can be seen directly below the brick. The drain point is about 4" aft of the pickup point at the lowest point in the tank.
I do not believe that the current pickup point is suitable for my jet engine application. Jets rely on fuel to maintain the flame. If the fuel flow stops even for a short time, so does the flame. I feel that an aerobatic system would be prudent, so that any negative g imposed due to any cause will not cause engine failure.
So my challenge is to incorporate an aerobatic fuel pickup system to replace the existing system. This is where I need hints.
I shall explain the geometry of the fuel tank in order to make the setup as clear as possible to readers.
Around 5" forward of the current fuel pickup point is the foward face of the fuel tank. The nosewheel retracts such that it almost touches the forward face of this bulkhead, so it is not possible to mount a through bulkhead fitting for a flop tube to this bulkhead.
There is also a baffle to be installed around 8" aft of the current pickup point (sorry, no photo of this). This baffle has a flapper valve in its base to allow fuel to move forward to the pickup "collector box" and prevents fuel from flowing aft at nose-high attitudes and low fuel states. The baffle will also have a gap at the top.
So, what are my options for fuel pickup here? The fuel line from the tank will run aft, probably along the side of the structural keel (fuel tank) to the engines which are just aft of the back seat. What Aircraft Spruce (or other) components might be recommended?
Thanks,
Dave
