Airplane owners know the dread — that Number 10 envelope in the mail from the Federal Aviation Administration. Using your airplane registration information (you did update the FAA last time you moved, didn’t you?) they’ve hunted you down to tell you … it’s time to spend more money on your airplane.
Airworthiness Directives, or ADs, are formal notices from the Government that a problem has been found with your airplane, its engine, a component or modification the Feds knows is or commonly is installed in your airplane model. An AD will mandate certain actions on the part of the airplane owner, within a specified time frame.
Examples: ADs range from minor items to very serious items. Sometimes they are almost laughable in their scope — for instance, installation of a placard to remind the pilot that running out of fuel may cause injury or death. Most ADs are more practical and necessary, like the Cessna seat rail ADs that mandate inspection and replacement (if necessary) of seat adjustment latches that have been known to slip. On takeoff failure of the latch has sent the seat sliding back, leaving the pilot out of reach of the panel, but usually pulling the yoke all the way back in the process. Other, more dire ADs address critical issues of airworthiness. The Beech T-34 Mentor wing spar ADs come to mind, borne out now in two in-flight wing separations involving these ex-military trainers used in simulated-air-combat-for-hire.
The Trend: Most discussions and descriptions of ADs eventually involve the word “death.” In almost all cases ADs come down from the FAA as the result of the recommendations of the National Transportation Safety Board (NTSB) following a fatal accident, or when mechanics in the field file Service Difficulty Reports (SDRs) that add up to a negative trend in aircraft airworthiness.
THE LETTER — WHAT YOU GET
The AD announcement received by the registered owner contains a brief description of the reason for the directive — whatever glitch that’s been found to provoke the FAA to require an inspection or a change in order to maintain airworthiness. The letter provides detailed technical guidance on the process of inspecting, placarding and/or repairing defects. It also stipulates the length of time the airplane is allowed to fly before compliance is required. Often the work needs to be done within the next 100 flying hours or at annual inspection, whichever comes first. More urgent items may require compliance before the next 25 flying hours are logged, or even fewer.
Emergency Grounding Order: In extreme cases an AD will require compliance “before further flight” — meaning you have to park the airplane where it is until your mechanic signs the airplane off as having met the requirements of the Airworthiness Directive. By regulation, such an airplane could not even be granted a “ferry permit” to legally fly to a better manned location where the AD compliance could occur. (Although I’ve heard of cases where FAA offices issued permits anyway, and local mechanics signed the airplane off as “airworthy” under special provisions for the ferry flight.)
WHAT TO DO
When you get an AD letter (and if you are an airplane owner, you probably eventually will), read it over, then talk to your mechanic. Confirm that it applies to your airplane and schedule the work if needed. If it doesn’t apply to your airplane for some reason, it’s a good idea to have your mechanic enter a statement to that effect in your log’s AD list.
Some owners and aircraft owners’ organizations take the view that ADs are often promulgated by aircraft or equipment manufacturers’ legal departments to cover their ass…ets, so to speak. While manufacturer’s Service Bulletins and so-called Mandatory Service Bulletins (“mandatory” for aircraft warranty work and often a real good idea for continued airworthiness) often come through the mail from the aircraft factories, they are not Federally imposed, nor do they have to be accomplished for Part 91 (personal) airplanes.
…IN THE REAL WORLD
The reality is that no manufacturing process is perfect, and “recalls” sometimes happen. In aviation, the difference is that it’s usually the airplane owner, not the manufacturer, that pays for the inspection or repairs (there have been notable exceptions, such as Teledyne Continental Motors’ engine crankshaft ADs in the late 1990s…. and Lycoming’s engine crankshaft Service Bulletins in the early 2000s, where most of the costs of owner compliance the factory paid for). As the general aviation fleet continues to age (see Aging Aircraft Part 1 and Part 2) expect more ADs to be the norm — such airplanes have been in service far longer than their designers envisioned they’d ever last, and the highest-time airplanes of each make and model are in reality performing age-related flight test for the remainder of the fleet.
EVALUATING YOUR OPTIONS
Often, industry and owner’s groups look at the problem that prompted the Airworthiness Directive and design a less intrusive, less expensive means of meeting the same level of safety. Once the proper professional engineering work has been approved by the FAA, the result becomes an Alternate Means of Compliance (AMOC). Vendors or other groups can often get an AMOC approved and in that case, the Feds will issue an amendment to the original AD … and owners will get a revised letter in the mail.
TAKING A STAND
As one chat room participant recently wrote on this issue, if your reason for opposing an AD stems from objective science showing the problem is nonexistent or extremely unlikely, then it’s time to join the opposition. If you oppose an AD solely on the costs of compliance, it’s time to either comply with the AD or buy an airplane that’s less expensive to maintain. Most Airworthiness Directives are the alternative to permanently grounding entire fleets of airplanes as they age or defects are found.
BOTTOM LINE: Flying is not cheap, but there are ways to reduce the cost of flying. Noncompliance with Airworthiness Directives is not one of those ways.