Before we actually start to cut and shape metal the team at Competition Fabrications thought it would be a good idea to re offer up the Rotax 912 to the airframe again.
This is now post the exhaust completion part 1 and oil matrix initial placement
With the Jabiru removed again we have a ‘relatively’ blank canvas !
The offering up of the 912 showed that the oil tank is going to be a tight fit , especially if we allow for a degree of gap at the top end where the firewall angles inwards. We removed the rear left exhaust stack to allow the oil tank to be inserted from below. Positioning the tank to allow clearance at top AND below (for water pump pipe to exit) we could define a slight re angling of the exhaust outlet to provide greater gapping.
Next we looked at the top cowl projected alignment, taking an extended line from the P2 screen, over the tank to the nose.
We agreed that the nose bowl could be rounded and shaped a little more to raise its highest point and allow a cleaner, straighter line for the overall nose shape. This means the new cowl could largely match the old lines.
Although the old cowl has no way of fitting it provided a useful ‘line of sight’ and potential cheek shape that we could replicate in the new cowl.
What todays exercise showed was that I need to plan to relocate some firewall parts i
- Regulator
- Fuel pump
- Andair fuel filter
- Throttle feed line.
- Choke feed line
The Regulator is an easy move and can probaly just drill one more hole and shift the whole thing left and bung the old hole up.
Stepping back and looking at the Pump and filter positioning it was a bit naff !
I didnt have a fuel pump until only a couple of years ago ..and fitted in what looked like a useful gap on the firewall
Moving both upwards .. (they are both mounted at the bottom of the firewall) means i gain the space back at the lower panel.. ie right where the exhibit body is going to sit.
Moving pump and filter also allows for more direct routing of tubing and so cuts down about 10″ of tubing.
The other firewall items include an oil catcher bottle which could be replaced with the water overflow required by the Rotax.
Finally, the Smokin airplanes splitter for the dual smoke outlet needs to be replaced by a single output, so need to source that and remove one braided tube.
Jabiru back in only 48 hours later to allow continual flying through the coming months as cowling begins to take shape.
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