Out of curiosity, do pilots usually pronounce it “pan-pan” or “pon-pon?” It is technically pronounced “pon-pon,” and sailors generally say it that way either because they’re a traditional bunch or because the Coast Guard guidelines mention the pronunciation. I notice the FAA’s pilot/controller glossary doesn’t mention the pronunciation.
Pan-pan. Because we speak English and sometimes bastardise the words we borrow from other languages.
Anecdote on pan/pon:
I’ve never been taught a specific pronunciation. Nor have I ever heard it or said it for real. In conversation with other pilots I’ve only ever said or hear “pan” like the cooking implement. “Pon” sounds to me like faux French.
A related question: Some non-US English dialects pronounce the word “may” about like Americans pronounce the word “my”. And pronounce “day” about like Americans pronounce “dye” or “die”.
In those dialects is the radio codeword “mayday” pronounced with the American long “A” sound or the American long “I” sound?
Heck if I know. But I bet Richard’s accent is one of those.
As a student pilot, this gave me pause. I learned ‘pon-pon’ while earning my sailing certifications. I assumed my flight instructor was just being obtuse when she told me it was ‘pan-pan’.
It is just “may” and “day” put together, so I guess to an American’s ear it would sound a bit like “my-dye”. Though I think if you actually said it that way it would sound like an exaggerated Australian accent with the reality being somewhere in between the long A and I sounds.
Saying “pon-pon” seems a bit like saying “sontimeter” for centimetre (don’t American nurses tend to say it that way?), a little unnecessarily aware of the word’s origins.
Merde-y Merde-y Merde-y!
Mayday is also used for emergencies in Ham Radio. I remember being told to say “Mayday” three times.
And, just for completeness, the lowest level of “pay attention” (at sea) is "securite, securite, securite". Used for reporting safety and navigational information so that none of the other safe words have to be used 
Whoever told you the word should be pronounced “Pon” is incorrect.
Panne in French is very close to the standard English pronunciation of “pan”
That would be the U.S. Coast Guard…
My bolding.
To me, the French seems like it’s between “pan” and “pon.” It’s more of a “pahn” and neither one in English is a good translation. It’s also often said as a two syllable word, pahn-nuh.
If the point were to pronounce it in proper French, we’d be calling maydeh or maydee instead of mayday.
It’s nowhere close to maydee. The final syllable in m’aidez is a bit clipped. So not may-day, but meh-deh.
Panne isn’t a two-syllable word either. It’s highly enunciated 
You win the thread!. Nicely done!
Wiktionary says its English pronunciation in IPA is “pæn-pæn” (to rhyme with can).
https://en.wiktionary.org/wiki/pan-pan
The US Coast Guard are free to suggest an alternative pronunciation of course but it’s not necessarily definitive.
No, of course not. I was making the somewhat irrelevant point that in the US, the ‘pahn’ or ‘pon’ pronunciation is doctrine for anyone who’s had recreational or commercial boating education as to one degree or another, all that flows downhill from the Coast Guard. So when Barbarian says whoever told us that pronunciation was wrong, that might be true linguistically, but it’s not true in the sense that it’s codified in US rulemaking.
Fair enough.
First off, thanks to everyone for an interesting thread. FTR, on this point in particular, it’s not clear to me now if I my churlish/snarky 1st reply was in order or not. But it pushed my buttons as to how the GQ dance goes when it’s good.
Yes, in fact I was going to post a cite to a “declaring emergency” from an airliner which I saw just before the original “Mayday” one in OP–one which pilots here take issue–from which I inferred the notion of standard vocabulary. So it too would have been another entrant to the ATC Babel commented upon upthread.
Speaking of the ATC/pilot/“mayday”-vocabulary/reality-in-the-air nexus, I just found this awesome vidwhich I want to share. Listen to the whole thing.
I also like one viewer’s post of what a pilot at rock-bottom (for such is the one in the vid) must have as his life-saving mantra: “Climb, confess, comply.” Have any of you ever heard/been taught this as well?
Didn’t watch the vid.
That, or very similar words to the same effect, are certainly the standard mantra taught to lightplane pilots about what to do when lost or getting there quickly.
By coincidence I just learned that, for the Catholic pilot, the Big ATC in the Sky or maybe later an FAA investigation, will ultimately need the cur, quicquid, ubi, quando, quomodo, quoties, quibus auxiliis log as well.
Seriously, the “confess” part always impressed me: years ago I was told what a [fighter] pilot is: someone who can go through a checklist while spinning out and on fire.