How do I know which ADs apply to my aircraft?
Updated · Wingman AeroCare, KFNL
Short answer: You find applicable ADs by searching the FAA's Dynamic Regulatory System (DRS) for your airframe, engine, and propeller models, plus every installed appliance such as magnetos, vacuum pumps, ELTs, and avionics. Then you check each AD's applicability section against your exact serial numbers and part numbers. The result is your AD status list, which 14 CFR 91.417(a)(2)(v) requires you to keep.
Why is this harder than it sounds?
An "aircraft" for AD purposes is really four layers of products, and each layer has its own ADs:
| Layer | Examples |
|---|---|
| Airframe | Cessna 182P, Cirrus SR22, Beechcraft A36 |
| Engine | Lycoming IO-540, Continental IO-550 |
| Propeller | Hartzell, McCauley, and others, by hub and blade model |
| Appliances | Magnetos, vacuum pumps, fuel pumps, ELTs, alternators, autopilots, hoses, and many others |
Appliance ADs are the most commonly missed, because they are not tied to the aircraft model at all. An AD on a particular magneto applies to any aircraft with that magneto installed.
Step by step: building an AD list
- Gather your data plates. Record model and serial number for the airframe, engine, and propeller, and part and serial numbers for major appliances. Logbooks and the equipment list help, but the parts actually installed are what count.
- Search the FAA's Dynamic Regulatory System. DRS (which replaced the older Regulatory and Guidance Library) lets you search ADs by product make and model. Run separate searches for each layer.
- Read each AD's applicability paragraph. Many ADs apply only to certain serial number ranges, part numbers, or configurations. "My model is listed" is not the same as "this AD applies to me."
- Check for superseded ADs. A newer AD may replace an older one. Your list should show the current AD and note what it superseded.
- Record the method of compliance. For each applicable AD, note how and when it was complied with, and for recurring ADs, when the next action is due (14 CFR 91.417(a)(2)(v)).
- Mark the ones that do not apply. Good practice is to list ADs that were reviewed and found not applicable, with the reason (for example, "serial number outside range"). This saves the next inspector from repeating the research.
What about alterations and STCs?
If your aircraft has a supplemental type certificate (STC) installation, such as a new engine, propeller, or avionics package, the products installed under that STC carry their own ADs. Under 14 CFR 39.15, an AD still applies even if the product has been altered, and under 14 CFR 39.17, if the alteration affects your ability to do what the AD requires, you must get FAA approval of an alternative method of compliance. An altered airplane is never exempt by default.
How often should the list be updated?
New ADs are issued regularly, so an AD list is only accurate as of the date it was researched. At minimum, it should be refreshed at every annual inspection, and recurring ADs need tracking by both hours and calendar date between annuals. Emergency ADs are sent directly to registered owners, which is one more reason to keep your FAA registration address current.
Can I rely on the previous owner's list?
Use it as a starting point, not a final answer. Lists can be out of date, miss appliances, or record compliance without enough detail to verify it. When buying an aircraft, an independent AD review is one of the most valuable parts of a pre-purchase inspection.
How Wingman handles it
Wingman AeroCare researches and performs AD and service bulletin compliance in-house for piston aircraft at Northern Colorado Regional Airport (KFNL). During an annual, any AD found due appears on your online estimate as an Airworthy item, with photos and an explanation. Owners in our Managed Maintenance Program get AD and SB tracking to the tail number, so recurring ADs are flagged before they come due rather than at the next annual. Learn more about AD compliance or call (970) 292-0719.