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"There are three parts to the problem: the system, the format, and the content. The system is actually quite amazing. The AFTN network connects every country in the world, and Notam information, once added, is immediately available to every user. Coupled with the internet, delivery is immediate.

The format is, at best, forgivable. It’s pretty awful. It’s a trip back in time to when Notams were introduced. You might think that was the 1960’s, or the 50’s. In fact, it’s 1924, when 5-bit ITA2 was introduced. The world shifted to ASCII in 1963, bring ing the Upper and Lower case format that every QWERTY key board uses today, but we didn’t follow – nope, we’ll stick with our 1924 format, thank you."

https://web.archive.org/web/20230104130153/https://www.faa.g...

"The FAA is changing the format for Notice to Air Missions (NOTAM) to align with international standards. The transition to the new format will ensure U.S. NOTAMs are compliant with standards set by the International Civil Aviation Organization (ICAO) and promote further global harmonization among neighboring Air Navigation Service Providers (ANSPs)."

ICAO NOTAM format

https://vat-air.dk/files/ICAO%20NOTAM%20format.pdf

Example! (decoder ring not included)

"Q) EGTT/QMRXX/IV/NBO/A/000/999/5129N00028W005"


Its even more amazing when you really sit down and think about all of the systems (many highly resistant to change like aircraft navigation systems) that all connect and utilize this service.

What appear like simple changes and proposals in the aerospace realm are extremely hard to execute and many times take decades (multiple) to come into play. Global services/systems are even harder.


I want to point out that lower-case is possible with ITA2. Start at 4.6 of ITU-T Recommendation S.2 / 11/1988 in the Blue Book, basically 11111 & 11011 11111 switch case in locking/unlocking mode.


OpsGroup, the organisation behind that guide is also worth mentioning. It's a self-organised advocacy organization for flight operations personnel. Apparently they have a longstanding campaign to reform the NOTAM system (as explained in the guide).

They also have a summary of today's incident: https://ops.group/blog/us-flights-delayed-after-notam-system...


Fun but deadly. They’re not wrong about the absolute avalanche of irrelevant data that will be used to show you “you should have known” - hence the proliferation of “interpretation” services.


100%. As a GA pilot who mostly flies under IFR, the NOTAM system is borderline useless to me.

For every warning about an approach being altered or a runway closed, there are 100s of "birds invof airport" or "unlit crane 50' AGL 5 miles from the field" NOTAMs. And even for the relevant NOTAMs, Foreflight will highlight them for approaches etc and ATC won't send you to a closed runway or taxiway.


Seems like it's the sort of thing that's borderline useless right up until the moment it's absolutely essential.

Like the smoke alarms in my house, which are actually wired up to mains so don't technically need a battery, but they still have to have a battery in them and will give high pitched chirps ever few minutes when the battery is dead. And since there's so many in the house, and the chirp only comes every few minutes, it's a PITA to find the exact one that needs replacing.

So annoying, and again it's wired to mains so it worked without batteries! Except in a fire the fire might fry the house's magic box of energy delivery leaving only the batteries as the power source and then I really really really want them to work.


I've had way, way, way, too many 'chirp' at 4am situations in my life. The alarms have _literally_ trained me like Pavlov's dogs that it is _always_ a false alarm, to the point where my sleep deprived brain stumbles through the door blindly into the hallway without even checking if there's heat or smoke.

Some of the other solutions here like cry wolf only if battery low _and_ power's out, or a dedicated LED to indicate a problem, or the one I keep thinking of; gently _saying_ there's a problem with a small sound clip of "bat" instead of an angry Chirp that must wake someone up would really help. The alternative that I've heard many others take is to just disable them entirely if you're in a rental. I'll admit that I've been very tempted to do just that for individual alarms which are overly sensitive to bathroom steam.


I started replacing the batteries in all of them as soon as the first one starts beeping.

I figure the batteries won't last much longer in the others and I don't need to go hunting.


> gently _saying_ there's a problem with a small sound clip of "bat" instead of an angry Chirp

Those do exist! At least one smoke detector in my house has voice (primarily to differentiate between smoke and CO alarms)


We recently had a house burn in our neighborhood during a power outage that was running on a generator. Generator itself caught fire, so pretty much would cover that exact situation.


Yes, it wasn't like this in my house until some years ago when we had a small expansion constructed and the contractor installed these in the new portions just as a standard thing he does, and said he was retro fitting the rest of the house that way too. ( We know him, friends, so we know he wasn't just trying to get extra $ out of us)

For a few minutes I thought it seemed a needless detail, until I realized that often enough people forget to change their stand-alone unit batteries and maybe deal with the the occasional chirp in an "I'll get to it" mindset until it runs down completely. Having it tied to the mains solves that because it's relentlessly annoying to hear that chirp at random intervals, and the battery is a nice backstop failover from the mains going unexpectedly molten.


I mean, it is code now to have them hardwired up. Actually, I think the requirement might be for interconnectivity rather than mains power. It's probably both in some areas. It's quite possible, depending on the extent of your expansion, that he was required to retrofit all of the smoke detectors in the home.


Interconnectivity is separate from mains (though both may be required) - the modern ones have to be set that if ONE goes off, ALL go off.

For those playing at home, get the ones that are BOTH ionization AND photoelectric: https://www.nfpa.org/Public-Education/Staying-safe/Safety-eq...


I wish those mains-powered ones would just shriek continually if the battery was low AND mains power failed; then you could kill the breaker and find it easily.


I wish they just had a steady LED from the mains power on them when the battery was dead. Seems much easier to me.


Yeah, I bet one somewhere has it, but most just flash-when-chirp which is kinda annoying:

This alarm has a low/missing battery monitor circuit which will cause the alarm to “chirp’” approximately every 30 - 40 seconds for a minimum of seven (7) days when the battery gets low. The chirp will be accompanied by a flash of the Safety Light. Replace both bat- teries when this condition occurs.

Some of the newer ones come with a built-in Lithium battery that supposedly is good for 10 years.


Your analogy is way off. If smoke alarms worked like NOTAMs, they’d go off every time someone strikes a match, lights the fireplace, turns on the gas cooktop, uses a hair dryer, or plugs in any appliance. Oh yes, when the house is on fire too. All have non-zero risk of inferno.

NOTAMs are full of pages and pages of goop — inconsistent, impossible to accurately filter, hard to read, at times unclear, and mostly noise.


I think you’d not argue that if you flight to the airport without ATC (there are plenty of those), reading NOTAMS about that airfield is kind of essential exercise before flight.


Yeah, NOTAMs come into play when the shit hits the fan; radios are dead and you can't reach the tower kinda thing, but in that case just be sure you declared emergency, then they (probably) won't get you much for landing on a closed runway or a taxiway.


It works in both directions. If someone hits a crane in the fog they will present a NOTAM and you cannot argue that you have not been warned.


What if the tower’s radio goes down?


They have backup transmitters and if everything fails (tower evacuation has happened) you talk to the overlying approach / tracon / center frequencies to check. And then after that, land anyway and self announce positions for other traffic.

It's basically the same as landing at an airport that doesn't have a tower. Happens every day at hundreds of airports.


It's all fun and games until you have an F-16 head butting you because you didn't pay attention to NOTAMs and the Vice President happens to be visiting your town.


But it’s up to airline how they present NOTAMS to the pilot in the briefing package. They can (and do) use geolocation present in some (many) NOTAMs to filter them out. For example do not show the NOTAM just because the flight path intersects with the airspace. They can do even better - consider not only location but also altitude range, the best flight planning systems can consider also estimated time of arrival of the plane near the location of the NOTAM and filter out those which are not yet valid or those which are expired (the validity range usually present in each message). This makes the problem of including the NOTAM a 4-dimensional - geographical location 2 dimensions, altitude 1 dimension and a time. Not the easiest to solve, but solvable. Of course for every dimension margins can be applied to accommodate re-routes or departure delays, or ATC commands. There is no written in stone standard of how to present NOTAMS. Newer may be displayed at the beginning, etc Not to say that they can (and do) separate airfield and airspace messages to segment the large set onto meaningful subsets. I mean there ways to make sure important information is not lost and less important available if needed.


Airlines aren't the only things doing "air missions" - there is software that filters out much of it, but it IS quite archaic (similar to how the "official weather" notifications are set out).

Look at the Ukraine one for a pretty scary example.


The official weather notifications (METARs/TAFs) can be displayed in more modern ways, but many pilots like the brief coded weather messages because they can be easily skimmed for an entire route of flight.

In my mind, AIRMETs were a bigger problem - they had limitations in terms of how they were geographically defined, time range, and lack of flexibility (e.g. differentiating turbulence vs LLWS vs strong surface winds for AIRMET Tango) - but that's been fixed with the newer G-AIRMET feed[1], which is based around BUFR[2] instead of plain text.

The catch being you can't easily convey G-AIRMETs via voice or in an non-interactive environment, so we still keep the legacy text-based AIRMET feed around in parallel.

[1]: https://www.aviationweather.gov/gairmet/help

[2]: https://en.wikipedia.org/wiki/BUFR


Nit: it's just "Ukraine" not "the Ukraine." See https://en.wikipedia.org/wiki/Name_of_Ukraine


Double nit: this was not a misuse the deprecated term "The Ukraine" but the correct use of 'the' attaching to "Ukrainian one" referring to the NOTAM basically telling everyone to remain clear of Ukrainian airspace.


nit RFI: What is it about "Ukraine" (phonetically maybe?) that makes me, a westerner in the US, want to put a "the" before it every time I reference it as a country instead of just, you know, using the name of the country?

I don't go around calling other proper nouns "the" (mostly). I don't call my son "Hey there, the Bob, how was school today?" (his name is not bob). But if I had named my son Ukraine then I feel like I'd change that sentence to: "Hey! The Ukraine, how was school today?"

Why is this a thing? I have a formal background in applied/computational linguistics and a bit of trivial searching doesn't really reveal why this is a general tendency. Hurt's my brain meat.


Depending on your age and general personal history, in the past it was very common to see references and use of "the Ukraine" to talk about the region/area as well as the country (that mostly covers that geographical area). It could be remnants of your recollections popping up subconsciously.

In this case it really was meant to be projected as similar to "Have you seen the Bob document yet?"


In German (maybe some other languages too?) it's common to use "the" to refer to a 3rd person, so if Bob's sister Charlotte came home from school but not Bob, she could say "The Bob went to the mall".

Seems like it's the same way in Finnish, Finnish F1 driver Mika Häkkinen referred to Michael Schumacher as "The Michael".


Here's some that you want to "the": Alps, Matterhorn, US Navy, Rock.


Maybe because it's similar to "the UK" (United Kingdom).


“The Yukon”


Whoops - yup, I jumped the gun there.


Triple nit: “airspaces” - there are 5 FIRs and 1 UIR in Ukraine https://uksatse.ua/index.php?s=330da740cf9126adde95bad0face2...


Try replacing it in the sentence - it doesn't work, "the" is modifying "one" not Ukraine.

I suppose it could have been written "the Ukrainian one" but the the would still be there.


Whoops - yup, I jumped the gun there.


This is my favorite quote: "In an unintended twist of irony, the agencies seeking to cover their legal ass are party to creating the most criminal of systems – an unending flow of aeronautical sewage rendering the critical few pieces of information unfindable."


Interestingly, that seems to be a US-only problem.


The linked booklet specifically refutes that idea, calling out Australia and Greece in particular but implying the problem is much broader.


This is hilarious. Really appreciate the examples of irrelevant clutter obscuring important information. Any UX designer can learn from this as an example of what not to do.




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