After some final work on the holes, the cowl bottom frame panel is finally finished, ready for priming, with (left to right) a row of nine drain holes, the 1-1/2" round gascolator fuel drain access hole, and two eliptical exhaust pipe holes. The drain holes are important because like any throttle body carb, the AeroCarb can drip fuel if the fuel valve is left ON after shutdown. At some point, I may add some small fiberglass fairings on the bottom for the exhaust pipes... just like a Mooney.

The Jabiru 2" prop flange extension has been reinstalled per JSB022-1, which requires precise methods of removing, cleaning and reinstalling the flange bolts with Loctite 7471 primer and Loctite 620 thread lock, carefully torqued to 30 ft./lbs. The Loctite 620 is rated for high temperature, as well as being very high strength. Another pre-start item can be checked off, and entered in the engine log.

The latest tasks spreadsheet is up. Alhough some testing/debugging remains, the highlight is completion of building the panel. After moving a couple of non-essential tasks to later sections, there are now just seven (7) build/install items left to complete before first engine start. Of those seven items, three (3) are more than 50% done already. Progress happens!

Positioning the oil dipstick door and spring loaded hinge on the right side of the cowl nose bowl is a little tricky. The objectives are a) maximize the opening, and b) achieve a flush surface. Adding to the challenge, the surface of the nose bowl here is not flat. The forward left corner of the door (bottom center in the photo below) slopes up a smidge as it heads toward the nose bowl's "bubble". The left/right position of the hinge affects both the opening size and the surface flush alignment, as does the thickness of the hinge attachment backing plate underneath.

Best wishes for a very Happy New Year to all those who have helped with this project, to the many visitors to this web site and the slightly more reality-based hangar, and to all those who share our passion for committing aviation.

Preliminary power up tests on the center panel have gone OK, so I've updated the headline photo with a "live" one showing screens lit up and some lights illuminated. Because several coax cables and wires are still hanging out in the wings and fuselage unconnected, I'm taking it slow and won't leave fuses inline for long on those circuits that may still be "exposed."

The oil dipstick door in the cowl is coming along. The spring loaded hinge from Non Stop Aviation will run fore and aft, on airplane right (left in this photo) and it will be fastened down with two Camlocs in the corner holes. While it's not ideal to have the hinge on the side from which the door will be accessed, due to the layout of things and the nose bowl's center top bubble form it was the best option. It actually won't be that big a deal to get at the dipstick. The two Camlocs were chosen for simplicity and security. Not quite as convenient as a pushbutton but not hard for any diligeint inspection.

A closeup of the supporting flange, made of .032, with the Camloc receptacle holes in the corners.

Another landmark day. For the first time, the whole panel is in place with all the avionics! Still lots of testing to do on the center section gear, and no doubt some debugging, but it's a great day night in MOFN.

Working on the static plumbing today. The static air pressure system is just a controlled pathway to the outside ambient air pressure, which is read by the altimeter (ALT) and the vertical speed indicator (VSI). For example, as outside air pressure drops, the altimeter goes up and, depending on the rate, the VSI may register some rate of altitude change, whether rising or falling.

After quite a bit of work, the status now is that with suction developed by "milking" the surgical tubing to an indicated altitude of ~ 2500 MSL, the descent rate shown (which theoretically is attributed to air leaking into the static plumbing) is not even measurable by the VSI, which has a resolution of +/-50 FPM. In other words, the leak rate (if that's indeed what it is) is 1% or less per minute. I may just call that good enough. In fact, the rate of change is so small, I'm tempted to attribute it to some other common and inconsequntial instrument error of some kind -- if only I knew what it was. But I won't.

The static system is less critical than the pitot system. In a non-pressurized airplane, it's really just designed to eliminate the effects of brief pressure differentials occurring in the cockpit from ventilation systems and the like -- otherwise the altimeter and VSI would work just fine using cockpit air pressure directly. Indeed, lots of planes don't even bother with an independent static air system. The ALT and VSI just react to air pressure changes in the cockpit. Even certificated aircraft certified for IFR flight must only demonstrate a static system with loss of <100 ft./min., starting from a mere 1000 ft. differential [FAR 23.1325] and this system exhibits less than 1/4 of that loss, starting from a much higher pressure differential. In short, this is truly one of those rare instances in which the system, although not "perfect" is well beyond "good enough."

Wahoo! I finally found and plugged the last teeny leak in the pitot system. (The pitot tube transmits air pressure created by the forward movement of the plane to the airspeed indicator, which converts the rising and falling air pressure to airspeed.) It took three steps to conquer. First, redoing all the 1/8" pipe thread connections to the instruments to make sure they were properly sealed brought quite an improvement. Second, I read a post from Wayne O'Shea on the Rebel Builders List archives from a couple years back, where he recommended warming up Parflex-type tubing used for hydraulic brake lines before connecting them. The Nylo-Seal tubing I'm using for the pitot system is equivalent, and warming and redoing those helped.

Still, no matter what I did, it seemed that the leak rate stayed very slow, but constant, so I decided there must be one leak remaining at one of the joints I hadn't checked lately. Sure enough, one of the nuts on an elbow down low where the tubing leaves the cockpitd toward the lower strut was the culprit. After warming and snugging it up real tight -- the whole system is tight. Real tight. When pressurized by a rolled up piece of surgical tubing, it's been holding a rock steady 92 knots of indicated airspeed (KIAS) for over half an hour! Actually, as the EFIS's warm up the area behind the panel, helped along by a work light on the floor below, the indicated airspeed has actually gone up. Say Halelujah! It's on to the static air plumbing now.