Piper Flyer Association - Technical Know-how, Serious Fun read more

Maintenance & Technical (165)

Questions and Answers – Anthology

July 2012

This month, we’ve compiled some of the most useful tips from Q&As published in Piper Flyer over the last year. The questions and answers you’ll see here are abridged; refer to the original publication for complete information, including photos, drawings and company resources. —Eds.

SEPTEMBER 2011
Q: Dear Steve,

I just replaced the starter on my PA-28… again! The starter teeth didn’t disengage from the ring gear after the engine started. What’s the solution?

—Tired of Buying Starters


A: Dear Tired,

If all you burned up was the starter, you dodged a bullet. Bendix-type starters stick on Lycoming engines. There’s two reasons.

The first is lack of proper lubrication of the screw-shaft the Bendix assembly rotates on. Either your technician didn’t put a shot of silicone spray on the shaft at the last annual, or rain, dirt and airborne schmutz contaminated the front end of the shaft at the front bushing.

Read more...

Adventures with Bill – Care and Feeding of your Gyros

July 2012

Returning to Waltanna (SN65) after a long trip, I noticed that my airplane, Bill, didn’t seem to be his normal bubbly self. I asked him why he was so quiet, and he said, “Well, I seem to be having some trouble with some of my gyros. Did you notice how fast the heading indicator precessed? Then on our last takeoff, the heading just danced around over a 90-degree arc.”

I said, “Bill, you know your gyros have been in the panel for 10 years. How about removing your gyros and taking them to the gyro doctor for a checkup?”


GYRO REPAIR FACILITY

Wichita has numerous specialty shops to repair almost every aircraft component. Terry Alderdice at Pressure Technologies suggested that I take my gyros to Nu-Tek Aircraft Instruments, Inc. in Augusta, Kan.

I called and talked to Steve Cannaby, owner and president, about my aircraft’s gyro symptoms. Cannaby said that with 10 years and 1,400 hours of operation, it probably was time to overhaul the heading indicator. That was all I needed to confirm that the gyros were coming out of the panel; then it was just a matter of taking Bill’s heading indicator and turn coordinator for the drive across town to Nu-Tek.

Gyro instrument repairs and overhauls are Cannaby’s specialties. He founded Nu-Tek Aircraft Instruments 25 years ago after almost a decade of experience in other Wichita-area instrument repair facilities. Today, Nu-Tek’s reputation brings repair and overhaul business from all over the world, including U.S. government locations.

Read more...

Questions and Answers – Vacuum System Troubleshooting

June 2012

Q: Dear Steve,

I own a Piper PA-28-181 and I have a vacuum system problem. From what I understand, the vacuum system in my Cherokee is similar to a lot of other single engine Pipers, so this is likely a system problem rather than a Cherokee problem, but here goes.

As I climb, the vacuum pressure drops off. On the ground it’s right in the middle of the green but the needle slowly moves toward the left side of the gauge as I climb. Above 7,000 feet the pressure indicates below the green arc.

During my private pilot school I was taught that it’s important to keep the needle in the green but I’ve kept a close eye on both the DG and artificial horizon instruments when the vacuum level drops and they both seem to indicate correctly.

Can you tell me what’s going on? What do I need to do to fix it?

—Sagging Vacuum

Read more...

Threaded Fasteners: More than Appearances

May 2012

 

Fasteners keep our machines together. They’re simple, strong—and often neglected, overlooked and misunderstood. They’re also critical to our machines’ condition, and ultimately to our own longevity. It’s worth looking at them and knowing what we’re looking at.

Bolts hold things together, or keep things from shifting. Tension pulls on the bolt; shear forces try to bend it or cut it off. (The best example of a fastener designed for use in shear is a pin.)

A bolt is usually stronger in shear than in tension (and it is stronger yet in “double-shear,” where it is supported in two places, with a center load), but it is in shear that we see most failures—precisely because engineers know how to load bolts optimally, and engineers try to put fasteners into shear rather than tension, when there is a choice.

A bolt in a tension application will sometimes have a reduced-diameter shank to prevent other things from rubbing against it; a bolt in shear is usually snug around its circumference.

Read more...

Side Window Salvation

 

May 2012

Are the side windows of your Piper airplane getting hard to see through?

Have you polished and rubbed with this and that cleaner to little or no avail?

If you’ve been blessed with a little common sense, have developed a semi-organized mind and can follow some step-by-step instructions, you’re a prime candidate to install a whole new set of side windows. It will take less than a day.

Changing pre-made side windows is one task that owners are free to do—and sign off, without supervision by a certificated airplane mechanic—under the preventive maintenance provision listed in Appendix A of FAR Part 43.

Read more...

Questions and Answers – Pitot and Static Checks

May 2012

 

Q: Hi Steve,

I am pretty new to airplane ownership and I have a question about a test my mechanic told me my airplane needed. He said that the pitot static system needed to be checked. He also told me that I would have to fly 35 miles away to the only avionics shop around here to get the check.

I know that the pitot tube is connected to the airspeed gauge and the static system is connected to the vertical speed indicator, the airspeed gauge and the altimeter.

No one has touched those instruments since last annual, so why do I need to pay $250 for this test?

—Testy

Read more...

Questions and Answers – Replating a Spinner, Tire Woes and Auto Gas

April 2012

 

Q: Dear Steve,

I have a tire problem. Actually, it’s more of a pilot error problem. I am the proud and happy owner of an Archer III. This is a good airplane for me because it’s simple, it performs well enough for what I want, and doesn’t cost a whole lot to maintain.

I almost always fly by myself. Not always; I enjoy flying Young Eagles flights, and am planning to sign up to do Angel Flights as soon as my new business gets going.

However, I’m going through tires like Starbucks goes through a Seattleite. I just can’t seem to keep my feet under control while landing in crosswinds, and the airport I fly to most often always has a crosswind. I get worried and nervous because I have locked up the left brake—and scraped off hundreds of dollars’ worth of tire rubber—three times now.

Do you have any suggestions?

—Gotta ‘nother flat one

Read more...

The High Cost of Cheap Maintenance

April 2012

Getting what you pay for isn’t always a good bargain 

 

You can find it at almost every General Aviation airport. A little sign on the bulletin board, or a business card taped to the self-serve gas pump, advertising annual inspections for some ridiculous price like $200.

We all know that it is not possible to perform an annual inspection on even the simplest of General Aviation aircraft for the sum of $200, yet there it is, in black and white. What’s disturbing is the fact that these guys stay in business, which would indicate someone is utilizing those services.

Owning an aircraft can mean unanticipated expenses, and you don’t want to spend more on maintenance than you absolutely have to, but at some point you have to ask yourself, “Can I afford cheap maintenance?”

What I mean by this goes well beyond the obvious. I’m sure it is perfectly plain to you as aircraft owners that if there were an incident or accident which involved the federal agencies or the insurance companies, that you—not the mechanic—would be held responsible if it were found that inadequate maintenance was the root cause of the problem. FAR 91.403 spells this out.

Read more...

Questions and Answers – Comanche Fuel Tank Bladder R&R

March 2012

 Q: Hi Steve,

My 1960 Piper Comanche 250 has safely and comfortably carried my wife, my daughter and me to some of our most memorable adventures for the past 20 years. We have also been able to attend to my wife’s mother much better because our Comanche reduced the required travel time.

After all this, I arrived at my hangar last Thursday to find a strong smell of gasoline and soon discovered a steady drip of Avgas from the inboard section of the right wing.

Why do I have a leak? I’ve never had one before.

—Gassy Man

Read more...

Aircraft Maintenance Records

March 2012

 Aircraft maintenance records can be a source of confusion for many aircraft owners and pilots. What information is necessary, what inspections are required, and determining whether an aircraft is in fact airworthy according to the maintenance records is important.

Unfortunately, airworthiness is not limited to the physical condition of the aircraft but in fact is a catchall term that can be used to describe the physical condition of the aircraft as well as the records and whether they indicate an inspection is overdue.

Most all aircraft in the General Aviation fleet are issued a Standard Airworthiness Certificate. This certificate remains valid as long as the aircraft meets its approved type design, is in a condition for safe operation and maintenance, preventive maintenance, and all alterations are performed in accordance with 14 CFR parts 21, 43, and 91.

Read more...

Questions and Answers – Acrylic Windshield Repairs, a Leaky Compass

February 2012

 Q: Hi Steve,

I haven’t been flying my Piper Pacer very much lately. Money is tight, and Avgas is expensive right now. I do tie my Pacer down outside.

I was out there with my broom brushing the snow off of the wings, tail and fuselage when I accidently whacked the windshield with the broom handle. I hit it right next to the snap vent. (The snap vent is in a two-inch hole in the lower left corner of the window. —Ed.)

Now I have a big crack radiating out from that hole. It’s about four inches long.

I called one of the local A&Ps for some advice. I flip-flop between this guy (who is competent at inspecting the must-do items, and does a good job of assessing the general health of the airplane) and getting aircraft repairs and advice from a more established and better equipped shop located 50 miles away.

Anyway, my tailgate guy—I’ll call him Larry—told me that it’s okay to sew up the crack with safety wire. Is he kidding? I’ll replace the acrylic windshield eventually, but right now, sewing it up would be much more affordable. Can I legally sew it up?

—Cracked

 

A: Dear Cracked,

Larry is correct. In Section 4, “Windshields, Enclosures and Windows” of Advisory Circular (AC) 43.13-1B, repairs are described. This AC says that when acrylic windshields or side windows are damaged, they are usually replaced “unless the damage is minor and a repair would not be in the field of vision.”

Under “Minor repairs” it says that if safety is not impaired, the crack may be repaired by drilling a hole at the end of the crack with a 1/8 inch (or #30) drill. Next, drill a series of holes with a #40 drill. The recommendation for these holes is that they be spaced ½ inch from the edges of the crack, and also spaced ½ inch apart for the length of the crack. Then a length of brass safety wire is threaded through the holes to “sew” the crack together. Cover the repair with clear silicone sealant.

AC 43.13-1B, which is titled “Aircraft Inspection Repair and Alterations; Acceptable methods, techniques and practices,” not only outlines the safety wiring sewing minor repair (which is very noticeable and may cause nervous passengers to express concern about the airworthiness of your Pacer), it also outlines a simple permanent repair.

The simple permanent repair goes like this: Stop drill the end of the crack with the 1/8 inch or #30 drill. Then use a hypodermic syringe and needle to fill the crack with a polymerizable two-part cement such as PS-30 or Weld-On 40. (Weld-On 3 is one-part cement, will also work fine for this repair, and is considerably less expensive than the two-part cements.) The hole is plugged by soaking the end of a 1/8-inch acrylic rod in the cement and then inserting it into the hole. Let the repair dry for about 30 minutes and then trim off the end of the rod.

After the repair is dry, the clarity can be restored by polishing. The polishing process consists of sanding the surface with finer and finer grits of sandpaper. Start with 320 or 400 grit sandpaper wrapped around a rubber or felt pad. Use light pressure and circular motions.

Rinse the sandpaper often in a bucket that contains fresh water and a mild liquid soap as a lubricant. Flush the newly sanded acrylic with running water, then move to 500 grit paper and repeat. Keep moving to higher grit paper until all the sanding and repair marks have been removed. Finish using fine rubbing compound and a circular motion.

Even for those of you who don’t have a window crack to fix, your aircraft might be ready for some TLC, too. There are also a number of kits that supply all the materials needed to polish out scratches and restore clarity to acrylic windows and windshields. A few names include Micromesh, Micro-Surface, Scratch Off, and Polysand. These are available at most aircraft supply houses.

Happy flying.

 

 

Q: Dear Steve,

My compass is leaking. I can smell it, and can see the fluid level halfway down the window. Is this easy to fix, or do I need to bite the bullet and buy a new fancy compass? I really like the looks of the SIRS compasses but wonder whether buying a new compass is money well spent since I always fly with both a panel mount and handheld GPS navigators.

—Catching a Buzz

 

A: Dear Buzz,

Your primary compass is probably an Airpath, which has been the standard in almost all production airplanes for decades. Variations in the fluid level due to changes in air temperature and atmospheric pressure are accommodated by a flexible diaphragm. Leaks are almost always caused by deterioration of the diaphragm or the front face glass gasket.

Repair kits, which include a new diaphragm, a new face glass gasket and a half-pint of compass fluid are very reasonably priced (less than $20) and readily available from almost all aviation supply houses.

Unfortunately, the only approved repair scheme requires that the compass be sent to an approved repair station, or back to Airpath Instrument Co. The Airpath repair manual is quite specific about the procedure. I checked the prices at Century Instruments in Wichita and they want $110 plus parts to overhaul and certify a customer’s Airpath compass; $178 outright and $155 exchange.

Since the price for a SIRS Navigator NV2-2400 compass is approximately $255 plus $30 to $40 for the mounting bracket, your decision will boil down to overhauling your Airpath, or upgrading to the SIRS.

I have a SIRS in my Comanche and I really like it. It’s got big numbers, the numbers are a highly visible day-glo green, and I believe it’s a little higher tech than the Airpath. Since you are well equipped with the navigation equipment you said you carry on every flight, it boils down to where you want to spend your money.

Happy flying.

 

Steve Ells has been an A&P/IA for 38 years and is a commercial pilot with Instrument and Multi-Engine ratings. Ells also loves utility and bush-style airplanes and operations. He’s a former tech rep and editor for Cessna Pilots Association and served as Associate Editor for AOPA Pilot until 2008. Ells is the owner of Ells Aviation (www.EllsAviation.com) and the proud owner of a 1960 Piper Comanche. He lives in Paso Robles, Calif. with his wife Audrey. Send questions and comments to .

 

 

Resources

 

Advisory Circular 43.13-1B

www.faa.gov, then type “AC 43.13-1B” in the Search window

Airpath Instrument Co.

www.airpathcompass.com

 

Century Instrument Co.

www.centuryinst.com

 

 

Read more...

Seat Belt Retractor Saga

January 2012

 

As we were flying along one day, my wife, who was PIC that day, said, “We need to do something with this shoulder harness. It’s ugly and crunchy.”

Well, our airport was to be closed for two-and-a-half weeks to resurface the runway. What better time to actually get the retractors rewebbed? Should be simple, we thought, as there are several aftermarket companies that will do it and return the units in seven days.

So, my wife Pam and I loaded up some tools and headed for the airport. The decorative cover over the retractor came off easily with only three screws to remove (and avoid dropping). There was only one nut to remove to free the retractor. Easy—not. No matter what we tried, the nut and bolt turned together.

Maybe you have to take the mounting bracket off the aircraft bulkhead? So we tried to loosen those three screws; no joy there, either.

Read more...

Questions and Answers – Cherokee Six Fuel Selector Leaks, Cold Weather Oil Cooler Controversy

January 2012

 

Q: Steve,

I have an early model 1973 Cherokee Six 260. The fuel tank selector valve is located under the rear seat. I noticed that I was using more fuel than I expected the last two times I’ve filled my Six’s tanks. I’ve heard that if the selector leaks internally, I’ll lose fuel. How does this happen? Can it be caused by a loose fitting or connection?

Thanks,

—Gas Be Gone

Read more...

Questions and Answers: Technical Publications, Progressive Inspections and an Inop EGT

01-13

Q: Dear Steve,

I received an email today and I am suspicious about opening it. The subject matter refers to the airplane I own, but this does not look like the Service Bulletins I am used to seeing.

Below is the link I have been directed to and it concerns a required inspection of the aft wing attachment fitting for my PA-32-300: https://system.netsuite.com/core/media/media.nl?id=15732&c=649290&h=e46decc92ad77fd4190d&_xt=.pdf

I would appreciate hearing from you
if you know anything about this, and if this link is genuine.

Thank you very much.

—What is This?

Read more...

Spark Plug Servicing and Replacement

December 2012

 Spark plug replacement and cleaning is a task that aircraft owners and pilots can easily do to maintain engine efficiency. I encourage aircraft owners to get involved in the maintenance of their aircraft, as a pilot aware of the mechanics of his or her aircraft is a safer pilot.

A component of maintaining an aircraft engine in good condition includes the regular removal, cleaning/inspection or replacement of the spark plugs as allowed by FAR 43 Appendix A (“Major Alterations, Major Repairs and Preventive Maintenance”).

Spark plugs wear out but can also just become dirty with use; they can become lead-fouled as well. Cylinder and engine problems can be identified by just looking at the tip of the spark plug.

Spark plugs, to be maintained in the optimum condition, need to be cleaned and re-gapped at no more than 100 hours (or as needed), tested and replaced when necessary. Some aircraft engines prone to lead fouling may require more frequent service to remove lead deposits.

Read more...

Questions and Answers: Mountain Flying Tips for a Cherokee Pilot

December 2012 - 

Remember that an aircraft wing always stalls at one angle of attack, but can stall at any airspeed.

Q: Dear Steve,

I’m in the fourth quarter of the game, age-wise, and have decided that it’s now or never! I’m planning a once-in-a-lifetime flying trip around the western United States and up into Canada next year. All of my flying—I have logged 880 hours over the last eight years—has been east of the Rockies. I’ve never flown in mountainous terrain.

My airplane is a Cherokee 180D and I’m going to pack it with a tent, sleeping bag and some emergency gear. I’m an experienced camper. I’ve been dreaming about this trip; I’m looking forward to seeing the sun’s rays crawl down across the western mountains.

What I am unsure of is this: Does my Cherokee perform well enough to safely fly in the western mountains, and does it have enough performance to get in and out of mountain strips?

A pretty experienced pilot here says I should install an angle of attack gauge before I go. He says it’s the best instrument I can have for mountain flying. What do you think?

And can you give me some advice on things to do before I go that will help me fly safely?

—Big Tripper

Read more...

Jump Start Your Plane – Should You?

 

NO, you should NEVER jump start an airplane that was certified with a battery as original equipment, unless that aircraft was certified with a dead battery and I’m not aware of any that have been.

Batteries are your power supply if and when you experience a failure with the electrical generating system.

FAR 23.1353(h) requires a battery backup for 30 minutes, but that regulation didn’t come out until 1987 and doesn’t apply to aircraft that were certified earlier. 

The CAA and JAA require 60 minutes’ backup power, and rumor has it that the FAA will follow.

With the introduction of electronic instrumentation, ignition and FADEC the requirement for dual generating and airworthy battery systems on single-engine airplanes is becoming standard.

Read more...

How To Survive an STC

January 2005

 

This portion of the article about the application process for Supplemental Type Certificates was generated by listening to aircraft owners, A&Ps and A&P/IAs across the United States complaining about Flight Standards District Offices (FSDO) no longer approving Field Approvals Form 337 for aircraft.

I don’t know what brought about the modification to FAA Order 8300.10, Volume 2, Chapter 1, Change 15, which listed unacceptable alterations, but after hearing complaints, the FAA was prompted to create Change 16 stating what can be altered under FAA given guidelines.

Form 337 serves two main purposes. One provides aircraft owner(s) and operator(s) with a record of major repairs or alterations made to only one aircraft, an airframe, powerplant, propeller, appliance, or spare parts (indicating the details and approvals). The other provides the FAA with a copy of the form for inclusion in the aircraft records at the FAA Aircraft Registration Branch in Oklahoma City. Form 337 is, basically, a history of the aircraft.

Read more...

Time Life Items

September 2004 -

Only big airplanes with jet engines have to worry about replacing things on a calendar or time in service basis. None of that applies to my airplane, or does it?

We all know that transport airplanes have to change landing gear, and starters, and engine components and many other components on a time table that is based on time the component has been in service, not the condition of the component.

The selection of what is on these time life lists is made during the certification of the aircraft, and sometimes items are added from service history of the aircraft. The time specified can be changed either up or down using the service history and some operators have different service times because of their specific maintenance history... The intention of imposing time life limits on some components is to improve reliability and safety of the aircraft by changing/overhauling components before they fail and cause a potential problem.

Read more...
Prepare for Next Year’s Inspection Now.

Prepare for Next Year’s Inspection Now.

The object of an annual inspection is to determine that the aircraft is in condition for safe operation and complies with the type certificate. Here are some practical suggestions from an A&P/IA.
I am often asked by aircraft owners, “What can I do to reduce the cost of an annual inspection?” and I will offer some suggestions and observations in this article. The key lies in preparation for the annual.

Owner Maintenance
Owners performing maintenance should coordinate their efforts with their mechanic/inspector. Check with your inspector prior to changing the engine oil and filter, as it is likely that the oil filter will be cut open and inspected for metal contamination during the inspection process—even if you just changed the filter five hours ago.

It has been my experience (and in my discussions with other inspectors, we all generally agree) that owner-assisted annuals may not really offer much reduction in cost, but are more like a training event for the owner. Owners shouldn’t be discouraged by this. Their participation in the annual inspection along with year-round preventive maintenance will pay off in the long run.

Unless the aircraft owner is experienced with the particular aircraft and has enough tools to do the work (removing inspection panels and seats, for example) without direct supervision of the inspector, there will be no real savings.

Regardless of whether the owner assists or not, it is important to understand that only the inspector is allowed to actually perform the annual inspection and may not delegate this to anyone. What this means is that an aircraft owner or mechanic can prepare the aircraft for annual and perform maintenance functions such as cleaning and greasing wheel bearings, but may not actually perform any inspection function.

Many times I have worked with owners and had them remove seats, clean the aircraft, remove inspection panels, even drain the oil and cut open the filter. Sometimes these operations went smoothly, and other times they did not. I have had owners actually damage their aircraft while attempting to remove seats or even when attempting to replace a navigation lightbulb.

Airplanes are delicate pieces of equipment and care is always necessary, so spend a moment or two contemplating just what you are trying to do. Consider the possible problems you may get into, and come up with a plan of action.
Rusted screws are a problem that can be dealt with in several different ways but one of them is not to use an impact driver on an aircraft screw that secures an inspection panel. Many times the removal technique depends on what the screw is attached to and of what type of material the screw is made.

Even more important than removing a screw is how to prevent a rusted screw from being difficult to remove in the first place. Cleaning your aircraft and keeping it clean can make the screw removal process much easier. Anyone can twist a screwdriver or pull the trigger of a screw gun; it takes a little knowledge and experience to prevent the screw from stripping in the first place.

If the screw slots are filled with paint, dirt or debris of any kind, it is likely that the slots will strip because the screwdriver bit cannot fully engage the screw while it is being turned out. Keep the slots in the screw head cleaned out and use a quality screwdriver in good condition, and it is likely most all the screws will come out without a problem.

Maintenance Records
Inspectors performing an annual inspection must have access to all of the aircraft, engine and propeller records. AD note compliance information is often recorded in the logs; major repairs as well as modifications to the aircraft may also be recorded in the logbooks.

In addition to an inspector’s access to the logs, the information should be easy to read and properly identified. This can make an annual inspection go smoothly without additional cost of trying to determine if an AD note has been accomplished, or when the next inspection is due.

Not only are clean logbooks necessary for maintenance, they also help with the resale of an aircraft. I have had the opportunity to speak with several used aircraft dealers and always the subject of maintenance records comes up. If you want to get top dollar for your aircraft, have clean maintenance records. Not only is it a plus not to have damage or accident history, but detailed records are also necessary: when the last annual was done, what was done, and by whom; when the engine was last overhauled, by whom, and what was done.

How about all the AD notes? Are they all accounted for? Are there any due? Are there repetitive inspections required, or is there an action that will terminate any further inspections?

What about the transponder and altimeter checks? When were these done last, and by whom?

Propeller records can also be important. As strange as it may seem, some propellers installed on classic aircraft are as valuable as the entire aircraft. Without records of AD notes and compliance data on the propeller, an aircraft could be nearly valueless.
As an aircraft owner, you are responsible for maintaining your aircraft’s records and this would include: 1) AD note listings for airframe, engine, propeller, and accessories such as radios, magnetos, and wheels; 2) Current weight and balance data; 3) Equipment listing that reflects all the installed equipment on your aircraft and any modifications or removal of equipment; 4) Flight manuals, modification records (such as 337 forms), instructions for continued airworthiness, flight manual supplements, placards, and markings on your aircraft.

As aircraft age, many of these paperwork items may be inadvertently destroyed, no longer legible, or missing. An inspector engaged in an annual inspection may not allow your aircraft to pass if this documentation is not available.
Get all of this information consolidated and in a format that is easy to access. Thanks to the Internet, free info is available from the FAA web site regarding AD notes, and a listing for your specific aircraft can be viewed as well as any ADs for the engine, propeller and accessories.

While you may not be able to sign off AD notes, an aircraft owner can make a complete listing of these and identify where in the logbook there is evidence that each one has been complied with or does not apply. Even if the AD does not apply, it is necessary that someone with the proper authority make a statement that it doesn’t apply—don’t just leave the corrective action information blank.
Does your aircraft require a flight manual? Do you have this manual on board your aircraft, and is it the correct one for your aircraft by serial number? This may be the one place that all the correct limitations are described and required placards are identified.  

jpg-Next-Years-Inspection-Pip-12-2010-2

Preventive Maintenance
Many aircraft are in dire need of preventive maintenance, yet few owners take the time to learn about what needs to be done, how to do it, and when to do it. Some of the things that are allowed to be done by owners to save money on an annual inspection are replacement or repairs of items such as seatbelts and shoulder harnesses.

Seatbelts must be kept in good condition without tears, cuts, or frayed material, and buckles must not be worn, cracked, or have elongated holes. Each and every belt or harness must be identified with a Technical Standard Order (TSO) tag. A TSO is a minimum performance standard for specified materials, parts, and appliances used on civil aircraft,” according to the FAA web site. —Ed.) It is possible to send seatbelts out to a company that specializes in repairs and often belts can be re-webbed. (Keep in mind that it may be cheaper to purchase a new seatbelt if the buckle or attaching components require replacement.)

Another task that will assist the inspector is for an owner to make certain that all required placards and markings (including the compass correction card) are installed, are legible, and are correct. Required placards are listed in the Type Certificate Data Sheet and additional information may be associated with AD notes and aircraft flight manuals.

Every fuel filler area must identify the type of fuel required and the quantity. Check your flight manual and type certificate data sheet (available on the faa.gov web site) for this information and make certain that the data is in fact correct for the serial number of your aircraft. A few numbers can make a difference.

Keeping your aircraft clean is probably the single most important action that an owner can do. It not only makes the airplane last longer, but also eases maintenance and can even prevent costly maintenance in the future. Clean up spills on the carpet, dry out the upholstery, and if your plane has water leaks, replace rubber door/window seals as necessary. Wipe off and rinse with fresh water any bug remains on your aircraft to include propeller, airframe, and engine as the residue can be corrosive.
Keep the seatbelts clean (use only gentle soaps or detergents) and wipe the oil off the belly on a regular basis. Oil, exhaust, dirt, and water mix to make an ugly mess on the belly of your aircraft and corrosion will take over if left there for extended periods.

Operational Considerations
The cost of an annual can vary greatly and so much depends on what happened during the previous 12 months. How you operate the aircraft, where it is parked or hangared, where you fly, how much you fly, who flies the aircraft and for what purpose all impact the cost of an annual inspection and associated maintenance and repairs.

The pilot’s habits—both good and bad—can be apparent during the annual inspection. I visited a repair shop recently and was discussing stabilizer repairs that were being made to a Piper Arrow. In this case, the pilot/owner had disposed of a soda bottle out the window and dented the leading edge of the horizontal stabilizer.

Another maintenance item that involves operation of the aircraft is abuse of the aircraft by extending flaps (or landing gear) at higher than allowed speeds. Even if you are extending flaps at the maximum allowable speed, this does impact the longevity of the flap tracks, the aft portion of the wing, and the flaps themselves. Take it easy, use good judgment and as pilot in command, make the decision that is correct for the situation. Go around, extend the landing pattern, and/or let ATC know you need more time or space if necessary.

Landing gear maintenance is another issue that is very important to consider. When was the last time you performed a full servicing of the nose landing gear? It is commonplace to add nitrogen in the strut to bring it up to the proper extension, however, the amount of hydraulic fluid in the strut is also very important.

Air/oil struts must have the proper amount of fluid in them to dissipate shock loads to the airframe and these units should be serviced using nitrogen, not air. Moisture in compressed air can corrode internal parts requiring expensive maintenance and can interfere with the operation of the strut, especially in cold temperatures. If the strut is leaking fluid or air, have it repaired quickly, as replacing a few seals is much cheaper than repairing a damaged firewall. Retractable gear aircraft have the additional demands of grease at the proper intervals. Grease that gets mixed with moisture and dirt/dust is especially hard on moving parts and typically contamination occurs while the aircraft is parked for extended periods. Not only is wear increased with dirty grease, there is a good possibility that contaminated grease, cold temperatures and a weak electrical system can combine to spell problems in the form of a gear-up landing.

Aircraft that are rarely operated can have additional maintenance requirements, particularly if they have retractable landing gear. Waiting for annual servicing of the landing gear may not be the most economical plan. I have in past articles written about preventing damage to an aircraft while it’s parked or during ground operations. If your aircraft is tied down outside, are the flight controls protected from banging against the stops during high winds? Are you parked near a runup area so that your aircraft is blasted with prop wash, dirt or stones?

Are you careful about where you do your run-ups and how your aircraft is positioned? The nosewheel should be straight, not turned, during a runup. The surface where you do your runup should be free from stones and gravel that may damage the propeller, and the nose strut should be properly serviced.

Do you take care in towing your aircraft, and are you always vigilant in not exceeding the towing limits on the nose landing gear? Not being careful during all operations can be very costly at annual time. Enjoy your flying, but be very mindful of what you are doing. Is your technique a recommended practice, or are you just doing your own thing?

Final Thoughts
Keeping the cost of an annual under control depends a lot on what you as an aircraft owner do during the months before the annual. Operate your aircraft occasionally or preserve it if you aren’t going to fly for a while. Keep your aircraft clean, and properly secure and protect your aircraft to prevent weather damage.

Keep the paperwork in a safe place. That will help in preserving the important records.

Finally, repair defects right away rather than waiting until the annual to correct something that is malfunctioning. If your airplane has even a hint of an exhaust leak, get it repaired immediately, as waiting could get expensive—or worse, cause carbon monoxide to circulate, poisoning you and your passengers during flight.

All of these things I have written about are easy to correct during the course of a year. Waiting until the last minute to prepare for the annual can get ugly and expensive. Do your homework, develop a plan of action, and communicate with your maintenance inspector as to what is needed. Most of all, enjoy your flying.
 
Michael Berry – ATP multi – 757/727 – commercial single land and sea – 15,000-plus pilot hours – Turbo Jet Flight Engineer, A&P/IA mechanic – former aircraft repair shop owner, airplane owner, 121 Air Carrier Captain. Send questions or comments to .

Read more...
Subscribe to this RSS feed

Cookies