Brakes Broken In

Another day of prep work at the hangar. This time, I wanted to break in the brakes with some high speed taxi tests (and the subsequent hard braking). Reliably at 35 knots the nose would come up and I had to focus to not have an accidental First Flight as she really wants to fly now.

I chose a rather cloudy and later pretty breezy day for this activity but at least I learned how to keep her on the taxi way when there are significant cross winds.
Before the wind picked up I was able to complete a WOT static RPM test. As I had pitched the prop to maximum I was expecting to be a bit low on RPMs, it turned out to be stable at 4650. 4800-4900 would be better but this will just affect the maximum speed and I am not concerned about this yet.

Finally I also completed the transponder check at the local FBO and I re-checked the ELT. Everything is a go for a First Flight.

Now lets hope the winds do die down as forecast...

Carbs Balanced

Over the last days I was working on closing up the access covers and reattaching the cowl. It is simply amazing how much time goes just into putting all those screws back in.

I also built a fuel nozzle adapter for the big Mr. Funnel fuel filter.

That way the Mr. Funnel can safely sit on top and hold the fuel while it is filtering through it. This should make fueling a bit easier.

I put the seat backs and the cushions in, for the first time both sets.

All the bottom covers went on and the avionics bay was closed up too.

And the triangle cover for the front of the vertical stabilizer also got attached.

And then today, the carbs were synchronized and the idle adjusted (in reverse order) down to 1400 rpm.

Everything is ticked off the list, except for some high speed taxiing and glazing the brakes and getting my transponder check done. I think I will do this on Wednesday with the First Flight on the following day.

Static System Tested

The most important thing I had to do today was to complete the static hook-ups on the steam gauges and to test the static system. Having a low leak rate on the static system was the requirement to be able to close up the tail cone and to close up the tunnel.

The sealant on my suction cup system had cured over night and so I was ready to go and connect it.

With the help of a HF vacuum pump (which didn't work well for filling the brake system, because you need a push approach rather than a pull (vacuum) approach), the setup was pretty simple.

The pump itself loses the vacuum fairly quickly which is the reason for putting the shutoff valve in line. The first tests showed a very large leak and the suction cup would not stay on by itself. A bit of blue tape fixed that problem.

The leak was on the back of the altimeter. I had mistaken the nylon plug as a hook-up point for the static line when indeed it was covering a 1/8" NPT threaded hole. I had the right plug to put in and attach the line securely which fixed the leak problem perfectly. Unfortunately, I destroyed my fine German ASI from Winter in the process by forgetting to disconnect the static line from the ASI. Running the altitude up to 8000 ft also increases the airspeed to an astronomical value and the inner mechanics took a permanent hit. I will have to send it in for repair.

The static system had a leak rate of 2:37 minutes to get from 1000 feet AGL to 900. Overall it took 11:22 minutes to get down to 600 feet. The cheap Chinese altimeter has a quite significant leak rate all by itself (tried it by putting the vacuum on the altimeter alone) and it hardly changed when adding the rest of the system so I suppose a pure Dynon system should do much better than this but it is still 2.5 times better than required for the PAP.

While the vacuum tests were running I took care of finalizing the pitot protector.

And fixing some loose cable ties that we found during inspection.

Then I went for the Grande Finale and started the covering of the tunnel by putting the aft bulkhead in.

Isn't it looking nice! The floor panels followed.

At some point I felt like the number of screws was about to match the number of rivets I had put into the plane. But that was nothing compared to the realization that you actually have to pull at least the left wing to get the panel for the flap handle on!
I could not believe it but there was just no way to get the aft part of the cover over the flap handle and under the wing spars otherwise. I actually ended up pulling both wings as one screw did not want to start in the nutplate and I needed a clear view to figure out why.

Eventually I prevailed and the whole assembly came nicely together. However, thinking about taking all this out again in just a year is driving me somewhat insane right now, so I choose not to contemplate this further.
The rest was simple - just a lot of screws still.

I also had my POH reprinted in the latest revision and on card stock to make it a bit sturdier and longer lasting. Considering my luck I'd assume that Van's is going to come out with a new revision by the end of the month.

And concluded a very long work day in the hangar. I am making very good progress though and the next things are:
       - installing the big cover in the seat pan
       - installing the seat backs and cushions
       - installing the lower cowl
       - balancing the carbs
       - installing the top cowl
       - some more taxi tests and engine run up to maximum power

==> First Flight

How would that be for a Thanksgiving?

Steam Gauges Installed

The first work day after the certification. It felt great! Now I am working for myself and not for the certification and no more ELSA restrictions.
So, I decided to install the steam gauges at this point as I'd like to have a backup for my Dynon system.

They fit nicely. Only the altimeter needed a bit of the paint removed from the edge of the cutouts.

Then I worked on setting up the pitot pressure test. I used a PVC hose attached to the pitot tube and long enough to be able to blow into it while watching the ASI.

I used a piece of 5/16" tubing as a sleeve to connect the pitot hose to the ASI.

Although the pitot tube is not secured inside the PVC tube, this setup gave me great leak test results. From 120kts down to 110 in 4 minutes and 17 seconds, the whole test took 24 minutes (down to 80 kts). I ran the Dynon in parallel once I had established the pressure and the gauge is within a few knots of the Dynon.
I might add two cable ties on the pitot tube side tomorrow just for good measure and longevity.

Unfortunately, I had forgotten to bring a few pieces of PE tubing to hook up the static ports of the ASI and the altimeter to the static Y-connector.
So I decided to attach the tail fairing instead. I reinspected the area closely before closing it up - for the first time.

The fit is tight and we will see if I get some chafing in flight. The thing that surprised me is that the trim assembly is not well centered within the fairing.

It really is the assembly as the rudder measurements in the PAP use the trim assembly as a reference point and my numbers show the offset is clearly to the right of the centerline of the aircraft. However, there is no bending or friction or anything, so I leave it as is for now.

I left airport after this task and brought some homework with me.

This suction cup is from a removable hanger and fits over the static port and stays clear of surrounding rivets. I drilled an undersize hole in the base and inserted a 1/4" PVC tube and sealed it in with the Dynaflex silicone. Once cured the silicone will be clear and it should seal well enough for a low vacuum test.
I plan on putting this over one static port rivet and once I put a vacuum on the system it should stay on by itself.
We'll see if it works...