It was time for the annual. Again. During the 13 months since the last inspection, Id flown my 1968 Bonanza V35A fewer than 35 hours and although little had broken in that time, I wanted to keep my costs down without compromising safety.
Clearly, that would mean an owner-assisted annual, which I had done when I bought the airplane three years before. That annual was part of the pre-purchase inspection and it was thorough and meticulous.
Being a hands-on guy-one of my hobbies is restoring antique cars-Ive always done all of the maintenance allowed under FAR Part 43.3 right out on the ramp, weather permitting. But could an annual be done on the ramp, too? I had my doubts. But then I noticed that a Beech Travel Air a few spots down from my own began losing parts of itself. I knew the owner from previous conversations on the ramp and found him working on his airplane the next Saturday morning. The Travel Air owner was working with Tim Dowd, a meticulous I/A who came with good references. All this sounded good, but I still wasnt comfortable with the idea of working out in the breeze.
Was it really practical? Dowd assured me that it was, as long as my completion schedule was flexible. We agreed that under his supervision, I could do all of the work I was comfortable with and that any work outside of FAR 43 preventative maintenance would be done under his direct supervision.
There would be a flat fee for the inspection, which he would do, and an hourly rate for any repairs or other work required. For an extra $40, Dowd agreed to treat the airplane with ACF-50 anti-corrosion treatment.
Because of mutual time constraints, the majority of the work would get done on weekends. Its possible that a perfect Bonanza could go through an annual in one hectic weekend but thats just not realistic. Knowing that the airplane would be down for a couple of weeks, we decided to stretch the sign-off to the beginning of the following month, thus removing any pressure to rush.
We agreed on a Saturday, two weeks ahead, to do the bulk of the work, with continuation on Sunday. In the meantime, I was to remove the interior and lubricate the airplane according to the instructions in the POH. Having Dowd working just a few airplanes down the ramp was reassuring in case I hit snags.
Early on Saturday morning, armed with all the tools I thought I would need, including a portable electric screwdriver, I began to remove the interior. I brought along quite a few small jars and cans for hardware and used them all.
There were only two questions for Dowd: Do the floorboards ahead of the rudder pedals really need to come out? Yes. And how about the pulley access panels? Not all, but enough to check the area where the step mounts for corrosion and cracks. Total time to remove the interior, not including the side panels, was about five hours and all the stuff fit into my car for temporary storage in my garage.
Drive Here, Drive There
I soon ran into one of the limitations of a ramp annual. A fitting on the nosegear wouldnt take grease and when I removed the nozzle, the fitting came off with it. The joint was disassembled and the caked grease and dirt were cleaned out.
I drove home to my workshop, carefully drilled out the remains of the grease fitting, which appeared to be brazed or pressed into a bolt, then tapped threads into it for a standard grease fitting.
Nice work, Dowd said. But Id created scrap metal. The fitting would have to be replaced with a new or serviceable part. No shortcuts. When I called Beechcraft…err Raytheon… to order the fitting, I was shocked to learn that even with a 15 percent discount, it would be $69.06, plus freight. During this same call, I learned that only the fitting was available. If I hadnt ruined the bolt by tapping it, I could have pressed a new fitting into it. Moral: Consult the I/A before venturing off on a fix-it mission. The lubrication continued through mid-morning on Sunday. The work was tedious, but all went well except for three more grease fittings on the left main gear that wouldnt take grease. These were screw-in fittings; removing and probing cleared the blockage and clean grease was flushed through. Lubrication all through the airplane, including control linkage behind the instrument panel took the rest of the day.
Changing the oil, oil filter, engine air filter and removing the fuel selector strainer, all FAR 43 preventative maintenance, finished the day off. The work ended on a sour note. The fuel strainer had a hole worn in it and it was partially corroded.
The strainer is the subject of a recent mandatory service bulletin requiring new parts. Despite an earlier MSB that puts a large red sticker right in front of the unit showing how to correctly install it, some moron apparently installed mine upside down.
When I called Raytheon, I asked about the price of the new parts versus the old. The original strainer has a list price of $137 and the new part lists for $171. I choked and ordered the new part, along with a new gasket ($8.70) and a gasket for the fuel injector inlet screen on the engine (60 cents).
When the parts arrived, it was obvious that I should have checked the MSB instead of relying on the person on the phone to send me the right part. The new part was a one-piece plate and spring assembly, replacing the original two-piece unit. I still needed the strainer.
To add insult to injury, there was no discount; they had charged list price. Another phone call arranged a return authorization and credit for the new part and an order for the strainer, $116.45 including a 15 percent discount. I kept the gaskets.
Later that week, while the interior was stored in my garage, I spent a couple of hours one evening using Pliobond to fix loose ends of seat coverings and trim panels. I re-glued the original insulation and sound deadening material that was separating from panels and floors.
Inspection day. One of the hazards of working on the ramp is questionable weather. The mostly sunny and dry forecast had changed overnight to overcast with scattered showers. I went to the airport early and removed all of the inspection plates and the prop spinner. When Dowd arrived, the airplane was ready.
He had good news on the AD search. The airplane required only a repetitive inspection/lubrication of the main landing gear uplock roller bearings, a visual repetitive inspection for cracks, a check of the ignition switch operation and the logging of an already-complied-with AD on painting the handles red and placarding the emergency window exits.
The basic airframe inspection went well; no faults were found. The ELT battery expiration date was the previous month. A test showed the ELT to be dead. A check of the battery, with a voltmeter, showed it to be dead, too. A new ELT battery ($41) proved the ELT was healthy.
Along with the new battery were instructions for it to reach its two-year service life. It seems the ELT battery will last two years if you store it in a temperature-controlled room, take it with you to the airport in an insulated box, then install it only after the airplane has reached a comfortable room temperature.
Be sure to remove it before the temperature changes on landing. In short, if you leave the ELT battery in the airplane, it probably wont last two years. The fuel filler cap o-rings were starting to crack and needed to be replaced. The packing o-ring in the cap should also be replaced at the same time (two each at $10.37 and 38 cents).
Next came the engine. While I ran the engine, Dowd produced a portable generator and air compressor. I removed the upper set of plugs, racked them and set them aside. The compression checks were excellent.
While I removed the rest of the spark plugs, Dowd began cleaning, inspecting and re-gapping them. The plug positions were rotated according to the engine manual instructions and reinstalled. Mag timing was checked and found to be within spec.
Dowd wanted to check the health of the hydraulic valve tappets, something I dont believe was done on the two previous annuals. We ran the engine again and with the engine still warm, I removed the rocker arm covers and each cylinder was checked, on its compression stroke, for rocker arm valve lash clearance.
The hydraulic tappets should retain their oil and there should be little or no clearance. Number 1 intake valve had significant play, which could be caused by a bad tappet or a worn cam. We wouldnt know for sure until the tappet was removed.
Since we didnt have a bench tappet testing set-up, it seemed more practical to just order a new one, also from Beech (somehow I just cant seem to say Raytheon) along with the required push rod tube packings needed for reassembly.
The tappet was $45.80 and the packings (2) were 52 cents each; not bad. Three silicone-rubber rocker cover gaskets, to replace those that didnt survive, were ordered from another source, at $6.00 each. Further engine inspection indicated that one of the rubber engine induction tubes was soft and showed signs of deterioration, probably from engine oil that can seep through the intake valve guides at low idle speeds. Most of the others showed signs of dry-rot.
This wasnt surprising. Although the factory reman engine has less than 1100 hours, it was installed in the airplane in 1977. I ordered six new tubes, which are now a silicone rubber material at $14.24 each. I later learned that the engine has eight tubes and the two best original tubes, still in serviceable condition, were left in place.
Shortly after we jacked up the airplane to cycle the gear, the first rain shower started. We needed a half-hour break any how. When we got back to work, we found that bushings in the nosegear showed some wear but werent yet bad enough to require replacement, a job that requires removal of the nosegear strut assembly and sending it off to a shop with special equipment. However, that job will need to be done soon. A small adjustment of the nose gear doors was made for a better fit. By late afternoon, the rain began in earnest so we called it a day.
Mid-morning on Sunday we started again. This was going to be a short day because of late afternoon commitments for both of us. The rest of the gear inspection, including retractions with the main gear doors disconnected, went well, with just a requirement for new springs on the uplock cables.
These little springs were replaced just three years ago and had already corroded to the breaking point. Also, one of the uplock cable length adjustment turnbuckles was not safety wired, which was easily remedied.
The doors were reconnected and the airplane left up on jacks for me to clean and repack the wheel bearings, while Dowd went off to test fly the Travel Air. By the time he got back, we disassembled the left gear knee joint. It gave up its secrets and was now clean, fully functional and accepting grease. The other joint problem was in the gear downlock brace. It would have to be disassembled with the gear in a partially retracted position. That and the last bearing repack would have to wait until next Saturday, by which time the engine parts and other miscellaneous parts would be in, allowing us to finish up.
I had spent about 14 hours of my time that weekend on the annual. Counting two hours spent working on the interior parts, my total time on the job was now about 32 hours.
The next Saturday was a weather washout. Dowd wasnt available Sunday. With my airplane down now for a month, and the four-day (for most of us) July 4th weekend beginning on Thursday, I was getting itchy to fly. Also, Dowd had other jobs and wanted to finish mine.
We agreed that there was no reason that I couldnt go ahead and re-install the interior and the prop spinner on Sunday. He would be able to finish the engine work on Monday, while I was out of town on business. We would meet again mid-morning on Wednesday to clean up details.
With no time pressure, I took my time to remove and recrimp loose nut plates and replaced a few that were missing when I took the floorboards out. A couple of loose corners and misaligned parts of the side panels were also fixed.
With a little re-gluing of the arm rest covers and replacing of some pulled carpet snaps, the interior looked better than before it was removed. Another hour to install the prop spinner and remove the wing tips so Dowd could inspect, and finish the treatment with ACF-50 made for a seven-hour day.
On Monday and Tuesday, Dowd changed the tappet and the inlet tubes and finished the ACF-50 treatment. On Wednesday, we jacked up the airplane, partially retracted the gear and tended to the gear downlock brace and bushing assembly. We reinstalled the downlock brace, and recycled the gear.
Everything checked out. Before the airplane came off the jacks, the left wheel bearings were cleaned and repacked. The engine was run and idle adjustment was made. The wingtips were reinstalled; we were done.
My time for the annual came to 44 hours. In addition to the inspection time, Dowd put in 11.5 hours over several days. The costs came in as follows: Inspection: $250; additional mechanics time: $230; ACF-50 treatment: $40; parts and supplies: $530.66. Bottom line: $1050.46
Given the time and money involved, is an owner-assisted annual, on the ramp, worth doing? You bet. Not only for the savings, which are significant, but youll learn a great deal about your airplane regardless of where the annual is done.
The practice is apparently more common than I had suspected. While I was working on my airplane, the owner of a Cherokee began taking his airplane apart with another IA/ supervising.
Words of caution: If you go the owner-assisted route, on the ramp or in a hangar, make some discrete inquiries about the airport policy. Some allow ramp maintenance, some dont. Find out before you strip the airplane. Further, if you live in Minnesota or some other cold clime and your annual is due in January, working on the ramp is out. Spring, summer and fall only, in most areas.
Make sure youre working with a dependable IA with references from someone you trust. I was lucky to find an I/A who was not only good but reasonably priced. When theres less cost pressure, theres less tendency to cut corners or defer items that should be fixed. Dont settle for a Santa Claus I/A wholl sign off anything. In the long run, thats more expensive and potentially unsafe.
If youre good with your hands, have the time and the tools, and arent afraid of work, you can save a bundle. Even if youre dangerous with a screwdriver, you can still learn a lot by just sitting and watching.
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-by Vince Pavone
Vince Pavone is a manufacturing manager. He lives in Southbury, Connecticut.