FAA A&P Oral and Practical Test — The DME Exam

After passing all three FAA knowledge tests, the final step before receiving your A&P certificate is the oral and practical (O&P) examination administered by a Designated Mechanic Examiner (DME). Unlike a computer-based test, the O&P is a face-to-face evaluation that can last an entire day or longer. The DME assesses not just whether you know the answers, but whether you can safely apply your knowledge to real aircraft maintenance tasks. Preparation and confidence on this day are earned through study and practice — not luck.

Written by the AMTprep editorial team · Published · Last reviewed

Written against the FAA primary sources cited at the foot of this page.

What Is a Designated Mechanic Examiner (DME)?

A Designated Mechanic Examiner is a private individual authorized by the FAA to conduct A&P oral and practical examinations on behalf of the Administrator. DMEs must hold an FAA A&P certificate with an Inspection Authorization (IA) and at least 3 years of experience exercising their IA privileges. They are found through the FAA's Designee Management System or by contacting your local FSDO. DMEs typically charge an exam fee ($300–$600+ depending on location and whether you are seeking one or both ratings), which is separate from any FSDO fees. You may choose any DME in any location — you are not restricted to your home FSDO area.

The Oral Examination: What the DME Will Ask

The oral portion of the O&P covers FAA regulations, maintenance theory, aircraft systems, and the use of technical publications. The DME draws oral questions from the ACS knowledge areas and skill elements for your rating(s). Expect questions on 14 CFR Part 43 (maintenance standards and return-to-service requirements), Part 65 (mechanic privileges and limitations), airworthiness directives, how to use a manufacturer's maintenance manual, and the theory behind systems you claim experience with. Answers must be precise — 'I would look it up' is sometimes acceptable if you explain exactly where you would look, but a vague answer on a safety-critical item will raise concern. Bring your AMT handbooks for reference if the DME permits it.

The Practical Skills Tasks: What You Will Do

The practical portion requires you to perform or demonstrate maintenance tasks selected by the DME from the ACS skill elements. These tasks vary by examiner and available equipment but commonly include: performing an inspection using an approved inspection document, measuring and recording airframe or engine dimensions, identifying and classifying a defect, using NDT (nondestructive testing) equipment, fabricating a fluid line or cable, conducting an engine run-up, and reading and interpreting technical data. You must demonstrate safe work habits — proper PPE, tool control, Foreign Object Debris (FOD) awareness, and correct documentation. A single unsafe act may result in a stop-and-discontinuance.

What to Bring to the O&P

Arrive at your O&P with: (1) all three passing AKTRs (Airman Knowledge Test Reports); (2) your completed and signed FAA Form 8610-2; (3) government-issued photo ID; (4) your logbook or experience record documenting the required 18 or 30 months; (5) your personal tools if the DME requests them. Some DMEs require specific tools or personal equipment; ask in advance. Dress professionally and arrive early — first impressions matter and a rushed start is a poor first signal to the examiner.

Common Reasons for Discontinuance or Failure

The most common reasons candidates do not pass the O&P include: insufficient knowledge of 14 CFR Part 43 and Part 65 requirements, inability to locate information in technical publications (maintenance manuals, IPC, service bulletins), unsafe practices during practical tasks (dropped tools, improper safety wire, missing hardware), weak knowledge of airworthiness directives and how they apply, and inability to explain the theory behind a system they claim hands-on experience with. Reviewing the ACS skill elements for every area you list on your experience record — not just the areas you are most comfortable with — is essential.

After a Discontinuance: Retesting

If the DME discontinues your exam because you are not meeting the ACS standards, you will receive a Notice of Disapproval or a Discontinuance. You do not have to retake the oral and practical from the beginning — the DME issues a Letter of Discontinuance listing which ACS areas were satisfactory and which were not. You may return to complete only the unsatisfactory areas, with the same or a different DME. Your written-test AKTRs remain valid until their 24-month expiration dates. Use the specific ACS codes from your discontinuance to focus your remediation before retesting.

How the Examiner Chooses What to Ask

The oral is not a free-form conversation, and understanding where the questions come from removes most of the fear.

The examiner works from the Mechanic ACS. For each rating you are seeking, they select subject areas and, within them, knowledge and risk-management elements, and they must cover a defined spread rather than dwelling on a favourite topic. This is why two candidates with the same examiner get different questions and why neither can be prepared for by memorising someone else's exam.

The second input is your Airman Knowledge Test Report. Every ACS code printed on it names a subject area the examiner is directed to revisit, because the written test has already established that you did not know it. This is the single most predictable part of the whole exam, and it is routinely the least prepared for. A candidate who passed the Airframe test at 72 percent walks in with 28 missed questions worth of codes attached to their name.

The third input is you. Examiners follow answers. A confident, correct, complete answer moves the exam on; a vague one invites a follow-up, and a follow-up to that. This is not a trap — it is how an examiner establishes whether an answer reflects understanding or recall — but it does mean that the shortest oral belongs to the candidate who answers cleanly the first time.

How to Answer an Oral Question

There is a structure that works, and it is worth rehearsing out loud before the day, because recognising a correct answer among three printed options is a different skill from producing one unprompted.

Answer the question that was asked, first, in one sentence. If the examiner asks what a fusible plug does, the first thing out of your mouth is what it does. Candidates who begin with context and arrive at the answer thirty seconds later sound unsure even when they are not.

Then add the why or the consequence, briefly. What the component protects against, what happens if it fails, what you would inspect. That is where risk-management elements live and where an examiner decides whether to probe further.

Then stop. Volunteering adjacent material invites questions on it, and a candidate who talks for two minutes will eventually say something they cannot defend.

Two more rules. If you do not know, say so plainly, and say where you would look it up — the ability to find the answer in approved data is itself an examinable skill and is worth far more than a guess. And if the answer is in a publication, reaching for the publication is usually the right move rather than a confession of weakness: a mechanic who works from the manual is demonstrating exactly the behaviour the exam is looking for.

Cost, Scheduling, and Finding a DME

Designated Mechanic Examiners are private individuals authorised by the FAA, not FAA employees. They set their own fees and manage their own calendars, which has practical consequences.

Availability varies enormously by region. In some areas you can be seen within a fortnight; in others the nearest examiner is hours away and books out weeks in advance. Start looking as soon as your written passes are in hand, not when you feel ready — the ready date and the available date are independent, and the 24-month expiry on your written tests is running the whole time.

Ask three things when you first make contact. What the fee is for the ratings you are seeking, and what it covers. What happens financially if the exam is discontinued partway. And what they expect you to bring — examiners differ on tooling, and some will want to know which aircraft or components will be available at the test location.

Your local FSDO can point you toward examiners in the area, and Part-147 schools generally maintain working relationships with several. Ask other candidates too. Examiners have reputations, and while every one of them is applying the same standard, the experience of sitting the exam is not identical across all of them.

Frequently asked questions

How long does the oral and practical exam take?
A full A&P O&P exam (both Airframe and Powerplant ratings) typically takes 6–10 hours spread over one or two days, depending on the DME, available equipment, and how efficiently the exam progresses. A single-rating exam is shorter but still commonly runs 3–5 hours. Plan to spend the full day.
Can I use reference materials during the oral portion?
This is at the DME's discretion. Most DMEs allow you to reference AMT handbooks and technical publications for practical tasks — that is realistic, since real mechanics always work from the manual. For regulatory questions, you may reference 14 CFR. The DME will note whether you needed to look something up versus whether you knew it, so solid foundational knowledge still matters.
How do I find a DME?
Contact your local FSDO or use the FAA's online Designee Search tool to find DMEs in your area. You can also ask your AMTS school, supervisor, or local aviation community for referrals. Some DMEs specialize in certain aircraft types or have well-equipped shops for practical tasks — it is worth asking about their setup before booking.
What if I fail one portion but pass another?
If the DME discontinues the exam, they issue a Letter of Discontinuance specifying which ACS areas were satisfactory. You retake only the unsatisfactory areas. The 24-month AKTR validity window still applies — complete the O&P before any AKTR expires.
How long does the oral and practical take?
For both ratings, plan on a full day, and be prepared for two. The exact length depends on the number of ratings sought, how many ACS codes your written test reports carry, and how cleanly you answer — an examiner who has to probe every answer is running a longer exam than one who does not. Ask your examiner what they schedule; most will tell you plainly.
Can I fail just one rating and keep the other?
The ratings are examined and issued separately, so it is possible to be successful on one and not the other. What normally happens when a candidate is not meeting the standard is a discontinuance rather than a bare failure: the examiner stops, issues a notice recording what was completed satisfactorily and what was not, and you return to be examined on the remainder rather than repeating the whole exam.
What should I do the day before?
Not cram. Review your ACS codes one last time, confirm the location, time and what you are bringing, get your documents into one folder, and sleep. The oral and practical tests judgement and communication as much as recall, and both degrade faster with fatigue than knowledge does. Candidates who stay up rereading a handbook the night before consistently do worse than candidates who go to bed.

ACS subject areas covered here

These are the FAA Mechanic ACS areas this guide maps to. Each page breaks the area down and carries free practice questions with worked rationales.

Primary sources

Related guides

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