Aircraft Maintenance Records Acronyms

As an aircraft mechanic, we all know that after completing a maintenance tasks we are required by the Code of Federal Regulations (CFRs) to make a record entry. As an former Aviation Safety Inspector (ASI) I often had to review aircraft records for compliance and as a mechanic we all know some aircraft records are written better than others.

The CFRs in Part 43.9 - Maintenance Record Entries
Except as provided in paragraphs (b) and (c) of this section, each person who maintains, performs preventive maintenance, rebuilds, or alters an aircraft, airframe, aircraft engine, propeller, appliance, or component part shall make an entry in the maintenance record of that equipment containing the following information:
(1) A description (or reference to data acceptable to the Administrator) of the work performed.
(2) The date of completion of the work performed.
(3) The name of the person performing the work if other than the person specified in paragraph (a)(4) of this section.
(4) If the work performed on the aircraft, airframe, aircraft engine, propeller, appliance, or component part has been performed satisfactorily, the signature, certificate number, and kind of certificate held by the person approving the work. The signature constitutes the approval for return to service only for the work performed.

Knowing we must write a description or reference the data is where this is a lot to be desired. Mechanics who do not reference the data, which is always the best course. However, sometimes a short description of the work performed is easier and this is where confusion comes in.

In many of the aircraft record’s you will see acronyms being used such as R&R, C/W, PCW, N/A or a statement “All ADs complied with”. In an aircraft records what do this acronym mean and should they be used?

Many times in aircraft record’s you will see this acronyms used with no further explanation this is wrong.

A description means - a statement that tells you how something or someone looks, sounds, etc. : words that describe something or someone. (reference Merriam-Webster)

A description should be sufficient in detail to permit a person unfamiliar with the work, to understand what was done, and the methods and procedures used. You don’t have to write a book.

I think an acronym means something a person may not mean the same to another person and this is where confusion comes in using them in aircraft maintenance record keeping. Mechanics should spell out “R&R” removed and replaced leaving no doubt the item by part number was removed and replaced. This is especially true when performing inspections “C/W” is NOT the correct terminology for documenting Airworthiness Directives (ADs) method of compliance. Stating complied with section bla bla, item number 1 as an example is the appropriate manner referencing the AD itself to show compliance and the method used.

Improper documentation of maintenance is too frequently cited in FAA enforcement actions. Part 43.9 and 43.11 are among the most common regulations cited. Maintenance records will either convict you or absolve you when the FAA and/or legal professionals come calling. Using acronyms has always been an issue trying to determine what the mechanic did or did not do.

Because of confusion with acronyms all Advisory Circulars (ACs) will have a list of acronyms that will be used in that document. All FAA manuals, orders, AC’s and AD’s will have a list of acronyms individually for that document only. In other FAA documents the acronym may mean something differently. Using acronyms in record entries is a liability that mechanics need not place himself or herself.

In addition, to not using acronyms sloppy writing that is not legible is unacceptable. If a record entry cannot be read clearly to describe what maintenance procedure was accomplish it is like it did not happen. In my career there have be many record entries, I could not decipher or understand as a mechanic. If a record entry cannot be understood the maintenance task may have to be repeated to show compliance and a new record entry in accordance with section 43.9 performed.

No votes yet


Good info but the grammar and writing leaves a bit to be desired. In some paragraphs it even obscures the meaning.

WOW! Stache there's a lot of good info here but there's some that's debatable. Let's talk...

First, let's start with the definition of an "ACRONYM". According to Webster, an acronym is "...a word (such as NATO, radar, or laser) formed from the initial letter or letters of each of the successive parts or major parts of a compound term; also: an abbreviation (as FBI) formed from initial letters." I put that out only because I don't understand your statement "I think an acronym means something a person may not means the same to another person and this is where confusion comes in using them in aircraft maintenance record keeping." WHEW! That statement's confusing to me.

I'm also confused as to what you're trying to pass on here. You lead out by talking about Maintenance Record Entries and the need for accuracy & completeness. I agree absolutely! But you go on saying "Maintenance records will either convict you or absolve you when the FAA and/or legal professionals come calling." inferring acronyms are the root cause of the violations. Well my friend, you will get bitten if your entry doesn't meet the requirements of the regs, acronyms notwithstanding.

I seriously question your statement that "...all Advisory Circulars (ACs) will have a list of acronyms that 'will be used' in that document." I know you know better! The word “will” infers it’s mandatory & AC's are advisory in nature, not regulatory, which means they have no teeth in enforcement.

As opposed to you, I see no reason why "C/W" cannot be used when signing off an inspection provided the rest of the description is completed. The same goes with R&R, PCW & N/A providing a completeness of information for that task follows.

I do, wholeheartedly, agree that “All ADs complied with” is totally unacceptable but that's NOT an acronym it's a phrase. As the late, great Bill O'Brien used to say, that means EVERY AD on EVERY aircraft, engine, propeller & appliance was done on YOUR aircraft. But that's so 1970s & I thought that subject was history.

To sum up, I submit that acronyms are a useful part of the maintenance record entries in that they provide succinct information while lessening space in log entries. The FAA sees the need for acronyms, they're listed in Part 1 & other locations on the web site. Acronyms, on their own, are not acceptable descriptions for regulatory purposes. They're like a dependent clause in English, surround them with the proper descriptive information & you can't go wrong...

I have always appreciated Denny’s knowledge and experience, and especially the fact he delivers to high standards. As professionals the more knowledge we have and acquire the more accurate our decision making. I have always thought “RR” was a bit dangerous, as one individual will define it as Removed & Replaced, while another will say it stands for Removed & Repaired, and yet the guy will say it means Removed and Reinstalled. In my opinion FAR 1 has already taken “RR” from us. I won’t share it with you because I know you want to look it up for yourself, and I would hate to tell you the ending to the movie.

There is however a list of Acronyms and abbreviations found in Appendix 2 of AC43.13-1B. Given the fact this is acceptable data, I personally find no reluctance in using these acronyms and abbreviations in my historical record entries.

On a side note, while you are in FAR 1 look up the word “person”. If the FAA’s definition of “Person” doesn’t clearly let us know the regulations were written by attorneys for attorneys I don’t know what does.

I'm playing devil's advocate here Buddy. As I understand your interpretation, "RR" [with no ampersand] could mean Removed & Replaced [ampersand included] and others could interpret "RR" as Removed & Repaired. Respectfully, Removed & Repaired would be an incomplete or inaccurate entry. You still must do the third "R" which is Reinstall or separate the actions.

Wilbur (or was it Orville? I always got the two mixed up.) taught me that "R&R" meant Removed & Replaced while R,R&R meant Removed, Repaired & Reinstalled, the complete cycle. If, in fact, you removed a component and repaired it but did not reinstall it, your only entry must be to document the removal. The repair would be a separate entry upon reinstallation:

e.g. #1 You remove #2 comm during an Annual Inspection and send it to your Radio Shop. They repair it and return it to you for installation. Among the Annual descrepancies should be a reasonable facimile of this: R,R&R #2 Comm (see tag attached). That's a totally legal entry for that action.

e.g. #2 You remove the same radio during Annual but it's not ready when the aircraft rolls. The plan is to reinstall whenever repairs are complete. You're only responsibility is to document the removal.

e.g. #3 You remove the same radio during Annual but it's not ready when the aircraft rolls. The owner decides to go O/H exchange. Your entry should read R&R #2 comm because that's exactly what you did.

NOTE: remember I'm just talking about acronyms here, so please don't bust my chops about I/A/W or S/Ns on and off, ops checks, TT, W&B or peripheral info in the entry. Just acronyms... LOL

Your thoughts?

I/A/W = in accordance with
S/N = serial number (or serial #)
TT = total time (NOT tach time)
W&B = weight and balance
LOL = laughing out loud

I am not here to bust anyone’s chops, but to share information that I know will get mechanics in trouble. The use of acronyms in record keeping in legal cases always comes back to haunt the mechanic that made the entry. As I stated above “A description should be sufficient in detail to permit a person unfamiliar with the work, to understand what was done, and the methods and procedures used.” I have seen lawyers will go after mechanics over what an acronym could mean since it was not spelled out. This is why I recommend to all mechanic not to use them in aircraft record keeping.

The key here is for a person unfamiliar with the work, to understand what was done by reading the record entry until the work is repeated or superceded.

Stache, we appreciate your postings and sharing of knowledge and experience from a career on both sides of the fence.

While I appreciate perfectionin grammer, only an idiot would complain about grammatical trivialities when the gist of the message is clear.

Please keep sharing and ignore the "holier than thou" posters with superiority complexes.

Let me preface this by saying I rarely attempt to impose my personal position on anyone. I respect and lean from everyone. As with maintenance, I have always placed a high importance on my documentation efforts. I strive for 360 degrees of professionalism. Its important to me that you read professionalism into my documentation. I personally avoid any and all reference to “R/R” as it is my opinion FAR 1 has already claimed this abbreviation. But YES, I do use I/A/W, S/N, and the abbreviations you referenced, but beyond that I stick pretty close to the list mentioned in Appendix 2 of AC43.13-1B. I also use Time Since Overhaul (TSO), and Time Since Inspection (TSI).

It’s my argument the FAA has seen abbreviations in logbook entries since day 1 in aircraft maintenance. Yea, they may not like them, but if they were really serious they would revoke, suspend our license, fine us, or generate a regulation preventing their use. To the best of my knowledge this has never happened. I would further argue, the FAA has very clearly permitted the use of abbreviations ref: FAR 1, and Appendix 2 of AC43.13-1B.

Look through Part 91 and tell me how many times the FAA uses the abbreviation “U.S.”. Now go too FAR 1, and find “U.S.”. It’s NOT there. You can find a definition for “United States”;however notice you never see a (U.S.) adjacent the word United States in the definition, nor do you find the abbreviation “U.S.”. So, it appears to me the FAA has invented and used an abbreviation they ASSUME we all know exactly what they wanted to say, but was maybe to lazy to spell out. And YES, we mechanics do know what U.S. stands for: Unserviceable, what else could it stand for?

On the grand scale of things I attempt to achieve two thresholds with documentation: I am trying to educate anyone and everyone on exactly what I did, to the point you should NOT have to ask me any questions relative to the work I performed, and equally important what I did not do; and secondly, I am trying to minimize my risk.

Respectfully Stache, "...don't bust my chops about..." was NOT meant to induce an adversarial response. My intent was simply to continue discussing ONLY acronyms without introducing tangental arguments into the discussion. My apologies for a poor choice of phrasing!!!

In simple language, don't get your tits in a wringer... (humor)

Guy’s I post to raise awareness not be offended or bust anyone chops so to speak. Having been on both sides of the fence as a full time mechanic and FAA maintenance inspector, I know what can and will happen to mechanics. This is why I think it is important we share our experience and knowledge with each other. What I really like is we can discuss items such as the use of acronyms and why it may or may not be acceptable. As a mechanic and regulator, I have used Total Time (TT) or Time Since Overhaul (TSO) in aircraft records. What I think would really help is in the front of every aircraft record is a list of acronyms that could be used, but there is not such a list.

The FAA does accept the certain acronyms in records such as when recording Total Time as (TT) or Time Since Overhaul (TSO) these two are very common or even Airworthiness Directives (ADs). These three are acronyms are the most common and other acronyms may have a different meaning. For this reason I suggest to spell out the acronym as I have above if you use more than once in a record entry.

I would like to thank everyone that has commented as it shows we are interested in doing what is right and helping each other learn.

I associate C/W with “Complied with” and CW with “Clockwise.” (I took a ton of math and science courses in college, and this was common terminology.) But I agree with the author that spelling it out is better than the TLA, especially with Part 135 records.