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Last Modified 31st October 2001
1st October Worked on the display processor that will be used to gather information from the AFA engine management system and drive the RMP and MAP gauges.
2nd - 4th October No building, working in Wellington
5th October No building, visitors for the evening
6th - 7th October
I did a trial fit of the instrument panel and, as a result of a couple of conflicts with cabling, I trimmed the panel back in a couple of locations. The back of the tunnel section shown on the left would normally need to stay except that I am covering the front of the tunnel with a sub panel and therefore the tunnel itself is superfluous. The top of the section that is remaining will house circuitry associated with the angle of attack indicator.
With the trimming done the panel fits very nicely. A check with a spirit level shows that the alignment of the panel is identical to the horizontal datum of the aircraft which means my turn and slip and artificial horizon will be correctly aligned for flight. You can see the new lower subpanel in these pictures with the green starter button and, just visible below, the choke.
Time
to dive into the back of the aircraft. First job was to make up a support plate
for the master contacter which I am locating behind the baggage bay bulkhead.
Positioning it on the bulkhead allows me to keep the wire from the battery to
the contacter under 9 inches.
I used a piece of glass clad plywood as a support. The ply was left over from earlier work and goes to show that aircraft builders should never throw anything away! This subpanel was then attached to the back of the bulkhead with a couple of 3/16" screws and rubber blocks to act as spacers and shock dampers.
With the contacter in place I was ready to terminate the main bus feed to the front of the aircraft. Terminating these large cables on the bench is one thing but terminating them in situ in the aircraft is another matter entirely... especially considering that I use a pencil blow torch to do the job!! I build myself a small safety surround out of aluminium insulator to project the body of the aircraft against heat and flame, thrust my head into the back of the aircraft, and lit up the blowtorch. Having successfully avoided setting fire to the aircraft and myself during the process I tested the connection then applied red heatshrink.
The
cable from the contacter to the battery is a lot easier to terminate as this can
be done outside of the aircraft. The next job was to get the LEM current sensor
onto the cable. After much sticking of tongue out of the side of mouth,
application of soapy water and just a bit of perspiration thrown in for good
measure I got the sensor onto the cable. Another couple of microns of sheathing
and it would have been a different matter.
8th October Wired up the current sensor to its loom.
9th October Dove back into the back of the aircraft and attached the main bus feed to the contactor.
10th - 11th October No building
12th October Took delivery of my Microair
T2000 transponder. I have seen some pretty impressive devices in my time and
this unit is seriously impressive! I worked on the covers for the two holes in
the baggage bay area and then spray painted these with speckle coat.
13th October I am remaking one of the smaller subpanels on the instrument panel to get around the conflict that I found between the ELT display and the AoA module. In place of the ELT display I am putting a digital 'hobbs' engine run meter which will be triggered by the RPM gauge when the engine goes over 3000rpm. Made up one end of the microencoder to transponder signal cable.
14th October No building, working in Rotorua.
15th - 16th October Wrote code for another onboard processor.
17th October - 18th October No building
19th October Europa issued a note in the latest factory newsletter expressing concern about aircraft that only had
a single gascolator filter to cover both tank outlets. They recently had a gascolator
filter partially block during flight and have recommended that dual filters be used on
all Europas. Less than a week later we had the primary filter clog up on ZK-UBD though the use
of the second tank outlet and its redundant filter turned this into a non event.
As a result I have decided to modify the fuel system on my aircraft.
I am retaining the gascolator at the lowest part of the fuel system and am adding the
original fuel filters in the tank outlet lines.
Removing the two original lines was a lot harder than putting the lines in to begin with.
When I put the lines in there wasn't a main wheel in the way! It would have helped to have another
two joints between wrist and elbow but I finally got them out without too many scratches.
The new filters sit in the inboard section of the seat pan so I drilled out two holes in each
section, one directly in front of the fuel tank outlet and the other about 5cm back from the
thigh support. I fitted plastic flanges on each hole and then laid in new hose leaving enough to
spare to allow the fitting of the filters. I gave my filters away to another builder some time
ago so I have had to order some more from Europa.
With the filters in the seat pan I couldn't use the original blue foam base so I made up a 1" wide
support flange and then glassed this over with some spare carbon fibre cloth. A piece of ply will
be fitted over the top later.
20th October When the glass had set I trimmed it back and then surrounded the pipe where it went through the glass with Tacky Tape, a black butyl self amalgamating space filler. I bought the Tacky Tape at Oshkosh and it is proving invaluable as a space filler and buffer for all sorts of things. I'd now add it to my indispensible list when building an aircraft. A hidden benefit of the change is that my fuel selector now has main pointing to the front of the aircraft, reserve to the side and off to the back which presents a more intuitive view to the pilot.
My next target over the weekend was to work on the messy bits that required crawling around the
baggage bay and the aft tunnel.
Terminating the wiring for the pumps and the master switch control was relatively easy
but was slow work due to the location of the wires. In between terminating wires I epoxied
around a dozen cable tie bases a various locations behind then bulkhead. Once the master breaker had
been wired up I checked the resistance between positive and negative lines with a multimeter to
ensure that there were no shorts and temporarily attached the main battery. Attaching the master
breaker control line to ground was met with a satisfying clunk from the main contacter and a less
satisfying 750mA drain on the ammeter. With a total current capacity of 20A, 750mA is quite a drain.
21st October Now that power is available to the front of the aircraft I can now begin the process of checking out each circuit in turn. The connection method is pretty basic but checks for shorts and bad wiring. All I am doing is having a fixed load (halogen lamp) as the test device. A fuse in line with this protects against short circuits. Each circuit is tested in turn with my Fluke ammeter and voltmeter in line and the current and voltage drop noted. The only exception to this is the fuel pumps which are already in place and now hum merrily when powered.
22nd October Mention the words Upper Pitch Stop to an experienced Europa builder and they'll either mutter something
about never going into confined spaces again or dive for the nearest bar to control the nervous twitch they
acquired. Tales abound of young children being shoved into the back of the aircraft, people getting cramp
while doing the job and having to being pulled out of the aircraft or, in one case, getting motion sick while doing the work. What task, you may ask, can have
such an effect... the seemingly simple task of attaching the pitch support bracket to the top of the aircraft
and adding the pitch stop bracket, that's what. The problem is that there is no way of doing this except by
crawling through the D shaped hole in the baggage bay bulkhead. Even the manual
refers to this as an "unpleasant task"
As it's important not to deform the pitch tube I went round the house gathering up pillows and piled them up
each side of the tube then, to provide a modicum of protection for my stomach, I laid a blanket over the lower lip of
the D. The bruises that appeared the next morning show that some more protection
at this location was required!
I crawled in through the hole and was able to get to a point where my lower abdomen was resting in the D and have
just enough room to work. I drilled the two holes in the first operation and then, in two seperate expeditions aft,
fitted nuts and bolts through the holes. The heat built up in the back of the aircraft very quickly and
there was quite a lot of perspiring associated with each bit of work.
I discovered the benefit of fitting turnbuckles in the pitch counterbalance support arm wires as the pitch arm was
striking the bolt head on the starboard side just before reaching its upper limit. I removed the lock pins from the
turnbuckles and adjusted the arm so that there was no interference. If I was making a Europa again I'd
ensure that the pin slots on the turnbuckles are uppermost in their normal position so that I didn't have to
ferret around underneath while reinserting the pins.
23rd - 25th October No building.
26th October I have been using a pair of dummy outriggers to keep my fuselage upright and, while they are adequate to the task currently, I am not prepared to mount the engine using the current supports. Luckily another builder has designed a very neat fuselage dolly which will suit my needs. First task for the day was to run around town sourcing the appropriate bits of aluminium. Once I'd found the bits I needed I spent the rest of the day with hacksaw and file shaping the pieces as required.
27th October Europa some time ago issued a mandatory modification to the trim tab pins which replaced the originals with thicker parts to prevent cracks during service. The replacement of the pins first required grinding off the glass supporting the pin plates then removing the plates before floxing the new plates into place.
28th October Rather than continue with laying the glass over the plates at this time I decided to check the operation of the tabs on the aircraft. My first discovery was that the nice clearance I had between the tabs and the stabilators before I filled and primed the surfaces had now disappeared. This leads to building rule #2998, always check clearances between surfaces before applying the final coat of paint. A few minutes with a permagrait spline soon established the clearances again. Second discovery was that the starboard trim tab was no longer in line with the port when the stabilators were level and in fact as sitting about 3mm high at the trailing edge. This meant that I needed to move the pin forward by
1.5mm. I ground off the flox ready for repositioning the pin but couldn't do any floxing as the rain meant that the humidity was over the 70% level.
29th October Floxed the tab into place.
30th October Checked the tab alignment again. Got it wrong... I should have moved the pin back by
1.5mm instead of moving it forward by 1.5mm. Ground off the flox again. Removed the pin plate again. Floxed the plate in place... again.
Received the Rotax 914 maintenance manual and engine monitoring software from Australia. This makes excellent reading. The monitoring software looks like it would be possible to capture the data in real time from the engine, process it to derive engine and power settings and then display these. Once I have the engine in place I'll test my theory and if the data isn't too difficult to decode then I'll use this data for my engine and power setting display. The advantage of using this data is that I can abandon manifld pressure as an indication of engine power and display engine power as a percentage just like turbine aircraft.
31st October No building
