Anything related to the construction of our RV-7 airplane
Sent a photo of N50KB in response to a query on Vans Airforce forum. Doug Reeves passed it on to Vans Aircraft where Rick Hayes passed it on to Lycoming. I received a call that Lycoming would like to have the aircraft on display at their Airventure booth in Oshkosh.
The paint job was finished on May 17. Dolly and I closed up the house and departed for Michigan on the 21st; she in her car and I in the Dreamweaver.
It took me 6 hours 38 minutes flying from Florida to Michigan, plus one fuel stop. Dolly required three and a half days. She plans on leaving her 2006 HHR in Michigan next winter and flying back with me.
The prime mission for N50KB during the ’18/19 winter has been to be painted. During most of the build I have had a design in mind, inspired by some of the spectacular paint jobs seen at EAA Airventure Oshkosh.
In November I started hunting for a professional paint shop as soon as we arrived in Florida. During a visit to their shops, each of three bidders was shown a black and white sketch depicting the design. We had a good discussion of what I wanted and they gave me an approximate cost.
It is amazing the range of prices I encountered. The highest price was 240% of the lowest. I chose Fosters Aircraft Restoration located on the Lakeland, Florida airport (KLAL), the home of Sun-N-Fun. Although the high bidder has an excellent shop, the price was beyond my budget. The owner of the lowest bid price shop was moving to a new location and could talk better than listen.
I found John Foster easy to work with. His shop is huge. On my first 12/13/2018 visit there were seven aircraft in the preparation area. These included two helicopters, a Citation jet, and other cabin class twins. His reputation for quality work is outstanding. Attached to the preparation hangar are three large (50′ x 50′ ?) paint booths. I told John I wanted Fosters to do the job and accepted the three month wait till a March 11th start.
As I write this on May 14th, the painting is almost done.
As part of the deal, Dolly and I were to disassemble and reassemble N50KB.
For the first step in the process Fosters crew masked surfaces that were not to be painted, and ScotchBright scored the aluminum surface. Then an acid wash was applied to promote adhesion of the following coats. This was followed by an alodyne anti-corrosion coating. Next as shown below all metal surfaces were sprayed with a two part epoxy primer.
There was considerable body work to be done in front of the tip-up canopy where it meets the front fuselage skin. I was amazed how the crew was able to make a 1/8″ mismatch disappear. Further, they were dissatisfied with their first attempt, removed the faring, and did it over at their own initiative. That has been their approach to the whole process allowing no blemish to exist. However, each of these steps takes time and the original four to six weeks has inflated to nine.
Near the end of April the white paint had been sprayed. Dolly and I drove to Lakeland to install the cowl and tail feathers, enabling the layout of masking for color stripes.
I visited Fosters last Thursday and most of the color work is complete with just some small areas to be painted. It is coming along nicely.
Tomorrow Dolly and I travel to Lakeland to begin reassembly. Vinyl N number, wing walk material and other decals are yet to be applied.
The Vans RV7 design has about three inches of unused space between the side-by-side seats. So, I built an insert to provide storage for sunglasses, handheld radio, drinks, etc.
It is made of 1/4 inch popular from Home Depot that I ran through a planer taking it down to 1/8 inch thickness. The bottom and sides of the box were angled to match the cabin floor which is not flat between the seats. The cover shown above fits either of the longer compartments. The smalest compartment was sized to hold my Yaesu handheld. Overall it worked out well and is a snug fit between the seats.
Difficulties, self inflicted and otherwise have been described in an earlier post. The first and second flights were on June 5th, 2018.
A video of the second takeoff.
And the second landing.
The initial flight testing is known as Phase I and covers the first forty hours of operation where no passengers may be carried. Other requirements such as a limited operating range are included in the FAA issued Operating Limitations. The purpose of Phase I is to verify safe operation and establish the aircraft’s performance characteristics which may then be placed in a Pilot’s Operating Handbook.
Due to the problems described in the previous post the summer had drawn to a close and we were wanting to return home to Florida. I was fortunate the FAA issued a Ferry Permit allowing N50KB to complete the last of Phase I on the repositioning trip to KBKV, Brooksville Regional Airport. I arrived home on November 16th. Dolly had her first ride two days later.
The engine was returned from Lycoming in February and sat until we returned to Michigan in April. Reinstalling the engine and getting ready for the FAA airworthiness inspector took from April 22nd to May 17th.
Those weeks were occupied by:
Ordering new gaskets, oil filters, cotter pins, etc
Remounting the engine and reinstalling starter, crankcase breather, fuel servo, throttle and mixture cables, fuel flow sensor, spark plugs, exhaust pipes and temperature sensors, fuel and oil pressure lines, manifold pressure line. cabin heater scat tubing, Pmags, alternators, oil cooler and oil lines, engine fuel pump overflow line, Earthx battery and engine grounding wires, baffling and plenum cover, flywheel, propeller, spinner and 19.5 lb squash plate.
Installing a quick drain oil plug on bottom front of oil sump.
Redoing the weight and balance.
Running a “sparking test” to verify correct wiring between Pmags and cylinders.
Rerunning a failed fuel “bottle test” and sending the fuel servo spyder back to AVStar for diagnosis and repair. There was a manufacturing burr in the #4 cylinder spyder outlet. Ran the test again and it checked out OK.
Checking out the tail wheel hoist built in Florida. Works Great!
Permanently installed faring at lower horizontal stabilizer to fuselage joints.
Fabricating a rudder control lock.
Designing, fabricating and installing a canopy lock sensor.
Installing HDPE canopy closing guides.
Test running the engine.
Richard Anderson of the East Michigan FSDO signed the builder’s log and issued the Operations Limitations document on May 25th 2018.
No airplane to fly. No airplane to work on. Waiting for the engine to be returned by Lycoming. Cold and snowy in Michigan. Waiting for spring at home in Florida. What? In Florida, and I’m complaining?
Hope recovered nicely when I read about a wooden tail lift in the VanAirForce forums. Having a way to raise the tail of the plane is a great help in draining all of the oil during engine oil changes. I used Sam Buchanan’s lift photo as a model and built my own as shown below.
The winch mechanism and the castors are from Harbor Freight. Dolly drove her HHR North in the spring with the lift stowed nicely in the back.
On Friday November 11th N50KB had its first engine run.
November 17, 2017
A visit was scheduled with a FAA FSDO inspector for the afternoon of Wednesday the 22nd. In the interim I completed wiring and testing the Pilot and PAX seat heaters; and sealed seven more firewall penetrations with red high temperature silicone caulk.
Wednesday morning I started the engine with the intention of taxiing to check the brakes. It ran rough and was shut down. The #4 cylinder was cold. Inspection showed valve movement was OK and another start was made. The engine again ran rough for less than a minute and was shut down. Instruments (Garmin G3X) showed the #4 CHT and EGT rose only to 150 and 205 degrees while the other cylinder temperatures appeared normal. An overly lean condition was suspected. The #4 fuel injection restrictor was inspected and blown clean with air.
The FSDO inspector arrived and was told of the day’s activity. I agreed to a suggestion we do an engine start. During the start sequence the #4 EGT was seen to rise rapidly and then decline. Other cylinder temperatures were normal. The airworthiness inspection was terminated. During post run discussion a fuel flow test and plug sparking test were suggested.
Fuel Flow Test
The fuel distribution test collected avgas from the four injector lines while the fuel boost pump was running. This photo shows the results.
From left to right the cups contain the fuel for cylinders 1,2,3 and 4. The overly lean condition of cylinder #4 is obvious. There was likely a problem in the AVstat fuel distributor on the top of the engine.
Plug Sparking Test
The plugs were removed and their cases connected to engine ground by safety wire. With the master and ignition switches on, the propeller was rotated by hand. Sparks were observed from the plugs connected to the left E-MAG. The plugs connected to the right E-MAG did not spark.
Brad at E-MAG Ignitions was contacted by phone. He led us through several levels of tests that at end indicated the right E-MAG was operating OK. He then asked me to remove the right E-MAG. I was to verify the magneto shaft is engaging the drive gear in the engine accessory case.
I removed the E-MAG. It’s shaft and gear look OK. I then reached into the accessory case to feel the drive gear. This is what my fingers found. A broken magneto drive gear in a factory new Lycoming YIO-360-M1B engine that ran a total of less than 1.1 hours, with over an hour of that time on the factory dynamometer.
The following Monday began a week of phone calls and emails with several levels of the Lycoming warranty organization. Dolly had returned to Florida and before driving south I proceeded to pickle the engine with fogging oil and desiccator plugs for the winter.
Eventually Lycoming agreed to send a packing crate and pay to airfreight the engine back to the factory. Dolly and I drove back to Michigan where I spent several days removing the engine from the plane and with help from friends preparing the shipment. I took many photos of the process. The engine arrived in Williamsport, PA on January 2nd.
Could not yet see the light at the end of the RV7 build, but knew it was getting closer. The list of accomplishments in the interim included:
Fastening the fuel tank “break away” tabs to the fuselage on each side.
Fabricating and installing the short fuel vent lines and connecting fuel supply lines between the wing and the fuselage
Making up brake lines with Berringer fittings to go from the firewall down to the wheel brakes.
Filling the brake calipers and lines up from the bleader valves to the reservoirs over the master cylinders
Final fastening the PAX baggage floor and PAX seat pan to underlying ribs with machine screws. This and other tasks may sound simple, however I found them to take significant time.
Finished wiring the flap motor and position sensor
Installing a quick drain valve on the left front oil sump drain.
Installing Clasic Aero aileron push-rod boots to seal out cold air.
Installing SCAT tubes from NACA air scoops to the instrument panel outlets
Timing of the PMags
Fitting the cylinder baffles and using the “Paper clip” method to trim the baffles 1/2″ from the cowl
Fitting the oil cooler to the right rear engine baffle; doing the install and connecting oil lines
Cuting and glassing the engine air intake snorkle between the air filter and the fuel servo
Installing the ignition wire protectors that I designed last winter
Closing up the six inspection ports in the wing bottom skins
Installing an alternate air door into the snorkle with control from the instrument panel
Installing all interior cover panels, baggage rear wall and pilot seat pan
Sealing the engine to baffle gaps with Blue RTV
Installing wing to fuselage faring strips
Installing seat belts
Whew, and that’s not all.
The Vans upper and lower cowl halves had to be trimmed to fit each other and the fuselage firewall. For October 30th we had a Halloween Lantern.
The cowl interiors were painted with three coats of white two-part epoxy.
I copied the practice of many Vans builders and cut an inspection port into the upper skin in front of the canopy. This provides access to the break fluid reservoirs, the voltage regulators and the forward sockets of the VPX power box.
Another deviation from the Vans standard is that I fabricated and installed a plenum cover over the top of the engine, rather than the usual flexible baffle strips that seal the baffles to the top cowl.
The potential advantages of a plenum in cooling efficiency and reduced wear on the cowl have been often debated on the Vans Airforce website forums. Casting of the plenum was discussed in an earlier post.
Clay risers were set on the plenum to verify 1/2″ clearance from the cowl.
Aluminum and fiberglass edges were set with platenuts for fastening to the engine baffles.
The Catto three blade wood/carbon fiberglass propeller was installed. Specifications:
Nickle leading edges
Design RPM 2750
Red Line RPM 3300
Prior to first engine start start the fuel tanks were calibrated and a weight and balance prepared. Both of these steps will be repeated as the W&B indicates a heavier spinner ‘crush plate’ will be needed to move the center of gravity further forward.
While we were in Oshkosh, WI for the annual EAA convention, Lycoming announced a manditory service bulletin for about 1300 engines that had been manufactured in 2016, plus all engines that had been overhauled with new piston rods around that time. Our engine serial number was one of those listed. The inspection involved purchasing and using a special tool to find those connecting rods that may have looser than specified bearings in their upper ends.
An FAA Airworthiness Inspector friend who once owned an aircraft engine overhaul shop helped me get the job done.
The photo shows the tool (a big coil spring attached to the #4 cylinder’s rod. If the bearing starts to slide out when the spring is compressed by six turns of its inner bolt, it fails. We were lucky all four rods passed. Note the red cylinder base o-rings that are used to keep the connecting rods from flopping around during the disassembly. The S/B was just a PITA that slowed progress by three days.