NOTAMs – notices to air missions (formerly notices to airmen) – are critical to safe operations because they contain the details of, well, everything and anything going on at airports and airspaces, which might impact flight operations.
New York (KJFK | JFK) is fixing up a taxiway? The details will be in a NOTAM. North Korea fired a missile that might encroach of Japanese airspace? Check the NOTAMs. Large flocks of birds are hanging around Mumbai? You got it, there is a NOTAM for it. Actually, we rather like this one about highly endangered birds for Chiang Mai, although sadly it probably won’t stop us flying into them.
All the critical information a pilot may need to know for their flight is notified to them via NOTAMs which means pilots, particularly those flying long haul, international flights, have a lot to read – often hundreds of pages of flight briefing information – to ensure they are aware of any threats and impacts to their operations. The International Civil Aviation Organization reports that there are 35,000 active NOTAMs at this time, with nearly two million new NOTAMs issued each year.
In order to keep it as short and concise as possible, the NOTAMs are written in a secret code, much like the weather reports. So, if you want to understand how to read one, then read on.
Where to find NOTAMs
One of the best places is the FAA website here. Click to enter, and you will be given the option to search for a location. Enter the ICAO or IATA code for your closest airport and you will be presented with a list of all the active NOTAMs for it. If you search a big international airport, like New York JFK, then the list is going to be long.
Here is an example we found earlier. This is a NOTAM for Dubai International Airport (OMDB):
A1184/24 NOTAMN
Q) OMAE/QMRLC/IV/NBO/A/000/999/2515N05522E005 A) OMDB B) 2404022130 C) 2404302215
D) 02 16 30 2130-2215
E) RWY 12R/30L CLSD.
The reason for this NOTAM is actually pretty obvious – runway 12R/30L is closed. A pretty critical piece of information for a pilot to know. But, there is a whole lot more information in this NOTAM too, so let’s decode it.
How to decode a NOTAM
The very first part – the A1184/24 – is the NOTAM’s name, if you like. The A refers to the FIR or aerodrome, the number is just a number really, probably how many there have been produced for that place, to date and the /xx is the year, in this case 2024. Now we get to the Q) section. OMAE is the issuing office, and the QMRLC is the ‘Q’ code for the NOTAM – a code that signifies what the NOTAM is all about.
Q codes actually hark back to the early twentieth century, and were used for communications between maritime radio operators. They tended to all speak different languages (and writing long messages in morse code is time consuming) so to help with this, 45 basic Q codes were created which could be ‘morse coded’ with ease.
These 45 Q codes covered the most common and required questions which were sent. For example, QRB meant “What is your distance?”, QRM meant “Are you being interfered with”. The ‘Q’ itself has no great meaning, but potentially comes from ‘query’. Current, modern day NOTAMs (and the number of Q codes involved) are much greater in number, but the intention of ‘coding’ them remains the same – it standardizes the way these are reported across the world (or tries to anyway).
So, back to the NOTAM. This one’s Q code is QMRLC. They always start with a Q, so jump straight to the next two letters – MR. These identify the subject. You can find a full list of decodes here, again courtesy of the helpful FAA, but we will do this one for you. MR stands for M – movement and landing area, and R – Runway.
The bunch of random numbers and letters after that are not actually random, but also not really applicable for us – the people wanting to understand the NOTAM for the purposes of our operation – they are more for the filing and making of the NOTAM.
The bit we need
The next part is the part we really need.
A) provides us with the location in the form of the 4 letter ICAO code, in this case OMDB for the airport. B) gives us the start date and time (21:30 on the 20th April 2024) and C) gives us the end date and time (22:15 on the 30th April 2024). This validity is important because not all NOTAMs might be valid for the time I am heading there.
D) provides us some further information on the timings and relevance of the NOTAM, in this case giving me some dates and the times the closure will take place on those dates. So even though the NOTAM is valid from 4-30th April, the runway isn’t actually closed that entire time. Finally E) which is as plain text as you can get.
Simple, right?
Wrong. While most NOTAMs are standardized, not all are of the same quality. Poorly written NOTAMs can be extremely confusing and may not clearly tell pilots what the actual impact is. Additionally, because of the many, many things that can be NOTAM-ed, the Q coding is not always correct making it hard for flight planning software to sift out the irrelevant ones. The result is often ginormous briefing packs for pilots to try and read, filled with out-of-date, irrelevant, or crane* related NOTAMs.
*There are always crane NOTAMs. New York JFK for example currently has 68.
The peril of overly long briefing packs was experienced by Air Canada flight 759, to their detriment, in 2017 when they came within 14 feet of another aircraft after lining up to land on a taxiway instead of the runway. Yup, NOTAMs were one of the reasons, because hidden away in amongst the many irrelevant notices was one critical NOTAM about KSFO/San Francisco’s parallel runway being closed, but it was obscured by the sheer quantity of other NOTAMs around it. Unaware that one of the runways was closed, the fatigued pilots mistook the runway that was open as the parallel runway, and assumed the parallel taxiway was the second runway, and aimed for it.
We need NOTAMs
NOTAMs remain the universal and standardized method of conveying critical information about operational status, threats and hazards and other real time practical information to pilots and being able to read their often abbreviated and complex coding is key. Thankfully there is also a movement to revise NOTAMs to reduce their number, improve their readability, and generally reduce the workload of pilots and dispatchers who rely on the notices for safety.
