My First Flight In Pete’s RV-9A

The lull in activity at DOG Aviation has been due to visiting San Diego to attend the wedding for a son of a long time friend.  While in California, just had to visit Pete and see his now one year old RV-9A. After a late afternoon arrival at Pete’s house we endured late Friday afternoon rush hour traffic and made the trek to Chino airport.

Unfortunately, I moved away from California just shy of the final completion of the RV-9A … so after spending years helping Pete pound rivets and assembling components, it was wonderful to finally have an opportunity to go flying in our handiwork.  Pete was just in the process of finishing up his annual inspection on the RV-9A and all that was left to do was perform an engine compression check and put the cowlings back on the airplane and go flying.

Pete’s freshly vinyl covered RV-9A with the cowlings off waiting for the engine compression check.

It was quite a shock to see Pete’s plane painted yellow with white wings …. No not painted, it is vinyl wrapped!!!  While Pete had the airplane out of service for the annual inspection, Pete had the RV-9A wrapped in vinyl as opposed to having the airplane painted. Pete had been keeping this under wraps, so to speak, until after the annual was completed so he could fly the RV-9A up to Big Bear to take official completion photos for his Blog using  the mountains as a scenic backdrop.

Pete and his marvelous RV-9A.

After the compression check was completed, we buttoned up the cowlings and while the sun was still high enough over the horizon to be legal we took the RV-9A up for a few laps around the airport.

Pete towing the RV-9A out of the hangar for our sunset flight around the airport.

The RV-9A ready for our short flight of making a few laps around Chino’s traffic pattern.

In the pattern at Chino turning down wind.

The RV-9’s instrument panel in flight.

Pete’s “RV grin”.

Turning for a short final on Chino’s 26L runway.

After flying the RV-9A, Pete (and I) had an even bigger “RV grin”.

WOW!!! Pete’s RV-9A truly flies great!!! It is so smooth, it is just amazing. Just an awesome flying airplane!!! 

Sometimes You Get What You Pay For

The wiring of the RV-12’s fuselage is almost completed except for a couple of items that are pending such as the wiring for the control stick which is on hold until Oshkosh and of course there is the nav/strobe and landing light wiring to finish up.  Frequent visitors may have noted quite a few days ago some of the lighting wires were pulled out of the connector to be replaced with shielded cable.

When pealing back the insulation on the shielded cable purchased for the modification, it was instantly evident the wire purchased was very old because both the shield and inner wires were very oxidized. Partially to blame is the DOG Aviation procurement department which exercised due diligence in obtaining the best price possible for the mil-spec Tefzel two conductor 18 gauge shielded wire. This was one of those cases where you get what you pay for. Anyway, I couldn’t bring myself to install old wire so ordered new wire which just came in.

Today the headset and mic jacks for the pilot were installed along with labeling the associated audio wiring. The same procedure was used to install the headset jacks as used on the co-pilot side … the insulating shoulder washers required being sanded down a little so the shoulders do not sit higher than the thickness of the seat pans. After tightening the mounting nut on the jack assembly, if the jacks can be twisted by hand from the underside of the floor pan with moderate pressure, the shoulder on the washer is still a little too high and requires a tad more sanding.

Placing the insulating shoulder washesr on the threaded shafts of the headset jacks prior to installing the jacks up through the holes in the floor pans on the pilot side of the fuselage.

Close up of the insulating shoulder washers (black) just under the floor pan.

After installing the headset jacks it is a good idea to use a test meter to verify that the jacks are NOT shorted to the airframe and also not shorted to each other.

Using the ohm meter to verify both the pilot side headset and mic jacks are not shorted to the airframe. The open circuit as indicated on the meter was measured between the jacks and the airframe … all is good.

The next task which should have taken 10 minutes took more like an hour. The two wires for the cockpit light needed to be fished into the roll bar assembly and brought through a tiny wire grommet just big enough for the two wires. But first a 30 inch piece of 1/4" vinyl tubing is used as a wire run conduit to protect the wires once inside the roll bar. It seemed as though it would be easy to just push the wires through the 30 inch piece but here to tell you, due to my stubbornness, it turned into a time sucking abyss. What could be so hard right? Well the plastic insulation on the wire drags on the vinyl making the first foot fairly easy but after that it became a total struggle. After investing at least 15 minutes, I was not about to pull the wires out and use a small pull string or heavy thread as should have been done from the get go. It took a long time, but the wires were finally worked through the tubing.

Slowly working the two cockpit lighting wires through the 1/4" piece of vinyl tubing. Unlike me, be smart and start off by using a pull string.

A piece of solid wire was fished through the small wire grommet in the roll bar and run down the inside of the roll bar to the right side of the fuselage. A very thin piece of waxed cord was then pulled back through the wire grommet and the waxed cord was then used to pull the two wires and vinyl tubing up through the roll bar.

The two cockpit light wires were pulled through the wire grommet in the roll bar using a thin waxed cord.

Co-Pilot Headset Audio Jacks Installed

Wiring the RV-12 continues … have been chipping away at making labels and inserting wires in connectors. Although some time was taken away from production for the first lawn mowing of the year (a sure sign of warmer weather) and to work out a few issues with running the shielded cable for the strobes and wiring in an  additional switch for the left landing light. More on that topic when I get it finalized.

The next step in the wiring section would have the builder install the push to talk button wiring in the control sticks and mount the control sticks so the push to talk wires can be dressed properly. Decided to take a pass on dong this now because I’m leaning towards installing a stick with additional switches for auto pilot, trim, etc. so want to hold off making a final decision on stick grips until after making comparisons at Oshkosh.

Next page - the fuel pump wiring received a little attention … the fuel pump power lead from the instrument panel and the red wire from the pump receive spade connectors which will attach onto a large capacitor seen in the photo below. (Which I’m assuming is used as an electrical noise filter). The fuel pump mounting bolt closest to the wire run receives an Adel clamp which is used to suspend the wires running down the center tunnel and is also the grounding point for the fuel pump’s ground wire. The Adel clamp needs to be drilled out to 1/4" to allow the fuel pump’s mounting bolt to pass through it.

Crimping a spade connector on the fuel pump’s power wire.

The co-pilot headset and mike jacks were installed next. One thing that is important to remember is audio jacks typically need to “float” and do not get grounded to the airframe. I have read more than one complaint about noise in the audio which ultimately ended up being caused by the headset jacks being installed incorrectly.

Looking closely one can see the shoulder on the black insulating washer in my fingers … this goes inside the mounting hole preventing the threaded mounting shaft on the jack from becoming grounded on the inside edge of the mounting hole. The other nonmetallic washers will insulate the mounting nuts from the floor pan.

The headset & mic jacks are installed using the above plastic shoulder washer, however the shoulder needs to be sanded or filed down a bit because the shoulder is slightly taller than the thickness of floor pan. After the jacks are slid up through the mounting holes the flat insulating washers are used to insulate the metal shaft of the jack from the aluminum floor pan.

Return from the future: There is an error in the prints regarding the wiring of the ES-00043 headset module connectors. Figure 2 shows the wiring for the connector from the wire insertion side … caution the connector’s pin numbers as shown in the plans are wrong. An update to the plans is coming from Van’s. I did not notice or fall into this trap because I was referring to the big wiring diagram and reading the pin numbers directly off the connector itself. Below is the bad and correct wiring for the ES- 00043 headset module connector as viewed from the wire insertion side of the connector with the locking tab on the bottom of the connector as shown in the drawing.

 

Bad as shown       6 5 4 3 2 1
in the drawing     12 11 10 9 8 7

Correct pin           1 2 3 4 5 6

locations              7 8 9 10 11 12

Before sliding the wires into the Molex micro connectors printed heat shrink labels were made to identify the wires.

Installing the co-pilot headset and mic wires into a Molex micro connector.

Co-pilot Mic and headset jacks installed onto the floor pan.

Spar Pin Safety Reed Switches Adjusted

After letting the epoxy used to enclose the magnets in the F-1217C spar pin stoppers cure overnight the first item in the agenda was to make the necessary adjustments to allow the reed switches to close from the magnetic field present when the fuselage spar pin is in the proper position.

This process requires a little trial and error along with patience. Initially when the right fuselage spar pin was in place and the F-1217C spar pin stoppers were properly seated in the locking hole on the arm rest, the reed switch did not energize. Van’s instructions say to trim away 1/32" from the spar pin’s tube handle that the F-1217C pin stoppers are inserted into. This requires removing the screw, pin stopper and spring from the assembly, grinding down the tube, deburring and reassembling the parts to try again. The instructions say to keep doing this but do not remove more than 1/8”. The reed switch for the right fuselage pin began working after the fourth cut so just a little shy of 1/8" of material was removed in total.

Checking the reed switch circuit with the right spar pin locked in place to see if the reed switch contacts closed from the magnetic field around the spar pin stopper. After the fourth trim all was well.

One may ask why trimming the steel tubing the spar pin stoppers slide into has any effect on the reed switches. Frankly, I could think of at least two better ways of doing this but in a nut shell the steel tubing acts as a shield because the magnetic lines of force will pass through the steel tube easily so they remain concentrated within the steel and don’t spread out with enough concentration to energize the reed switches. Trimming the tubing shorter at or below the level of the reed switch increases the amount of magnetic field that will be present in the vicinity of the reed switches.

The spar pin assembly on the left of the photo is the right spar pin after final trimming. Note the length of the tubing the spar pin stopper slides into is almost 1/8" shorter than the yet to be trimmed spar pin on the right.

The builder is striving for a fine balance here…. the reed switches should ONLY energize when the spar pin stopper is locked in place. You don’t want the reed switch to become energized anytime the spar pin stopper is in the vicinity of the reed switch, only when the magnet in the pin stopper is fully up and inside the locking hole on the arm rest. If the builder gets too aggressive with trimming the tubing, which could easily happen if the tubing is not trimmed in small increments, it will create a much larger magnetic field around the spar pin than desirable. This will likely allow the reed switch to become prematurely energized just by having the spar pin in the general vicinity of the reed switch … not good because we only want the reed switch to energize when the spar pin stopper is locked in the hole on the arm rest and at no other time.

The same process was utilized on the fuselage spar pin assembly for the left side. Overall it required less trimming and the reed switch was working great with just a little shy of 1/16" trimmed off the tubing. Once both reed switches were working flawlessly, the rest of the wiring was completed. Both the reed switches were wired in series and connected to a wire in the WD-00046 wiring harness that according to the drawing went to pin 5 of the connector at the instrument panel. An ohm meter was used to take a reading between ground and pin 5 of the connector and there was continuity. Removing a spar pin broke the continuity. Time to move on.

With both fuselage spar pins in place and locked in position, both reed switches were energized and there was continuity to pin 5 of the WH-00046 connector at the instrument panel … a good thing!

Work continued doing the mundane things such as making wiring labels and crimping connectors where necessary. All and all, good results for the day.

Reed Switch Roadblock – Detour

If this was The Amazing Race, based on the extra time spent dimpling, priming and making modifications DOG Aviation would be last at the checkpoint … but that’s OK, it is the journey that counts. And just as with The Amazing Race, occasionally there are roadblocks that become detours. Today was just such a day. The morning began by making up assorted heat shrink labels and connecting various wires to connectors.

Wiring up the Molex connector for the autopilot roll servo.

Next on the agenda was the assembly and wiring of the reed switches that are utilized as an interlock for the starter. The theory of operation is when the spar pins are locked in place, a magnet in the pin stopper inserted in the F-1217 fuselage pins pulls the reed switch’s contacts together and the RV-12’s engine can be started. If the spar pin is missing or not locked in place, the reed switch will remain open and not allow the engine to be started.  Sounds simple enough. There are two reed switches, one for the left fuselage spar pin and one for the right fuselage spar pin. The two switches are wired in series with one leg of the right reed switch tied to ground … so if both spar pins are in place, both reed switches will be closed allowing a ground to be sent to the instrument panel.

Installed reed switch assembly secured by an Adel clamp on the right side of the fuselage … note the reed switch circuit is tied to ground here.

The reed switches are installed in a cushion clamp and attached to the bottom of the F-1248 armrests. Some builders have had issues with the cushion clamps and the adjustment of the reed switches so they have made mounting brackets. It appears as though the alignment is good but if there is much difficulty adjusting the switches so they work, I won’t hesitate to make brackets.

Tightening the left side reed switch’s mounting hardware.

Have to say my hat goes off to builders who have installed these switches after the side skins are on. My side skins are still off and I could see and get to everything easily however, getting the screws and nuts on while compressing the cushion clamp was still a bit of a challenge.

Oh, the roadblock that became a detour … in order to properly test and adjust the reed switch instillation, the spar pins require having the magnets installed, which requires some assembly. Had the side skins already been on the fuselage, the wings would have already been fitted to the fuselage by now. Part of that fitting process consists of assembling the fuselage spar pins and their spring loaded pin stoppers which contain the aforementioned magnets inside. Because of not building in order and thinking I could first prime and paint the handles of the spar pins a bright red before they would be needed, the parts were not assembled.  Scratch that idea … so work was suspended on the reed switches and the focus was placed on the fuselage spar pins.

The two F-1217 fuselage spar pins and assorted parts that need to be assembled.

The two F-1217C fuselage pin stoppers require having a hole in them tapped for 10-32 threads. The stoppers were clamped into a V block and the tap was carefully run into the hole.

Tapping the hole in the F-1217C fuselage pin stoppers for 10-32 threads.

After tapping the holes in both F-1217C pin stoppers, they were temporally assembled (will still want to disassemble the parts for painting later so the screws were not set with Loctite per the plans) and the magnets were inserted into the hole in the center of each F-1217C pin stopper.

The F-1217C pin stoppers assembled and inserted into the F-1217 fuselage pins. Note the tops of the magnets can be seen in the hole in the pin stoppers.

Blue masking tape was placed around the edge of the hole in the F-1217C pin stoppers to make cleanup easier and a batch of JB Weld (what I had on hand) was mixed up and slathered into the hole thus hermetically sealing the magnets in the F-1217C pin stoppers for all eternity.

Magnets sealed into the F-1217C pin stoppers with JB Weld epoxy.