I really enjoy the ATC communications, but why do they say decimal?  Not sure how it is in other parts of the world, but here in the US, it's said 'point", which I'm sure most of you already know.  Lots of times, even that's omitted during readback.  For example, if ATC says "contact departure on 124.25 (one twenty four point two five), the pilot might say "over to departure on twenty four twenty five" or just "twenty four twenty five..."

14 minutes ago, SpaceForceCapt said:

but why do they say decimal?

EASA standard phraseology. FAA uses "point" I believe.

SERA*.14035 Transmission of numbers in radiotelephony
Numbers containing a decimal point shall be transmitted as prescribed in point (a)(1) with the decimal point in appropriate sequence, indicated by the word ‘DECIMAL’.

*SERA: Standardised European Rules of the Air

Edited February 21, 20224 yr by SAS443

Ah, OK.  Thanks.  Yes, I've only ever heard "point" here in the USA.

36 minutes ago, SpaceForceCapt said:

Yes, I've only ever heard "point" here in the USA.

Yep. I'm french (but fly in US as much as possible) and can't stop repeating here and here that there's SERA, ICAO... and the reality of US 😉 The best situation I met was just before vacating the runway at KLAS, receiving the ATC message "Contact ground point niner" 😉

 

Edited February 21, 20224 yr by vbazillio

33 minutes ago, vbazillio said:

Yep. I'm french (but fly in US as much as possible) and can't stop repeating here and here that there's SERA, ICAO... and the reality of US 😉 The best situation I met was just before vacating the runway at KLAS, receiving the ATC message "Contact ground point niner" 😉

 

Haha, I am actually listening to local ATC right now, and tower just told an aircraft "left when able, ground point seven."

Unless there is a conflict with some other frequency Ground will be 121 point something so often you will hear "contact Ground point seven".

It's because there can't really be any confusion when using the word decimal; it has three syllables so it can't easily be stomped on by a break in transmission, which is why the ICAO adopted it as the standard. There is also the fact that the word 'point' could refer to something else other than the frequency, such as a hold point at a taxiway junction; not very likely of course, but not impossible. Having said that, I do hear plenty of people say things other than decimal on the radio at EGCC. 

Edited February 21, 20224 yr by Chock

Fortunately I don't hear "decimal".  That is because I keep ATC shut off. I cannot stand all the "Generic" and "Please Expedite"!  So unrealistic and ruins the sim when ATC is on.

1 minute ago, fppilot said:

Fortunately I don't hear "decimal".  That is because I keep ATC shut off. I cannot stand all the "Generic" and "Please Expedite"!  So unrealistic and ruins the sim when ATC is on.

Understandable.  I was using Xplane in the past, and ATC was pretty much nonexistent, so this is a step in the right direction.  Would be cool if they could make the voices more realistic, but still kinda neat.

Radio comms in the US are very lax compared to other places I fly. They have a lot of unnecessary deviation from international standards too. It's very annoying when flight simulator things use the US FAA standard rather than ICAO for the entire world, e.g. runway markings, "position and hold", altimeters only adjustable in inHg, Flight Levels only started at FL180.

When i was a practising ATCO on multiplayer networks being called "London Center" (often by American pilots but others too) really annoyed me because the position callsign is London Control and all pilots have to do is read is that back, London Centre is the VDF and guard service. Like many nations there isn't "departure" either you usually speak to Aerodrome Radar.

Edited February 21, 20224 yr by ckyliu

2 hours ago, SpaceForceCapt said:

I really enjoy the ATC communications, but why do they say decimal?  Not sure how it is in other parts of the world, but here in the US, it's said 'point", which I'm sure most of you already know.  Lots of times, even that's omitted during readback.  For example, if ATC says "contact departure on 124.25 (one twenty four point two five), the pilot might say "over to departure on twenty four twenty five" or just "twenty four twenty five..."

It’s one of the things that I hope they address at some point in the sim. But at this point there are bigger fish to fry.

In the US, when announcing frequencies, the dot is called “point” as in 122 point 70, not decimal. This is required by the FAA and the only exception is as follows:

”ICAO procedures require the decimal point be spoken as “DECIMAL.” The FAA will honor such usage by military aircraft and all other aircraft required to use ICAO procedures.”

14 minutes ago, ckyliu said:

Radio comms in the US are very lax compared to other places I fly. They have a lot of unnecessary deviation from international standards too. It's very annoying when flight simulator things use the US FAA standard rather than ICAO for the entire world, e.g. runway markings, "position and hold", altimeters only adjustable in inHg.

When i was a practising ATCO on multiplayer networks being called "London Center" (often by American pilots but others too) really annoyed me because the position callsign is London Control and all pilots have to do is read is that back, London Centre is the VDF and guard service. Like many nations there isn't "departure" either you usually speak to Aerodrome Radar.

There’s nothing “lax” at all when dealing with ATC. And it may please you to know that “position and hold” which made complete sense and emphasized holding, has been replaced by the vague and confusing “line up and wait” which was a huge mistake IMHO. “Hold” is a command that pilots know. “Wait” isn’t a command pilots know or use. I wonder how many additional runway incursions have happened since that change about 10 years ago.

Some of the official international phraseology is probably due to English not being a native language for many pilots.

3 hours ago, SpaceForceCapt said:

I really enjoy the ATC communications, but why do they say decimal?  Not sure how it is in other parts of the world, but here in the US, it's said 'point", which I'm sure most of you already know.  Lots of times, even that's omitted during readback.  For example, if ATC says "contact departure on 124.25 (one twenty four point two five), the pilot might say "over to departure on twenty four twenty five" or just "twenty four twenty five..."

Comms in the USA are sometimes sloppy.  Controllers in the UK use perfect phraseology where in the USA controllers will even argue and be sarcastic - virtually never in the UK.

Edited February 21, 20224 yr by MrBitstFlyer

29 minutes ago, neil0311 said:

it may please you to know that “position and hold” which made complete sense and emphasized holding, has been replaced by the vague and confusing “line up and wait” which was a huge mistake IMHO. “Hold” is a command that pilots know. “Wait” isn’t a command pilots know or use.

And that's exactly why everyone else DIDN'T use "position and hold" because "hold" is more frequently said when ATC want aircraft holding short of the runway, not on it - "hold position" can be confused/misheard as "position and hold" in a busy environment despite meaning exact opposites when issued at the holding point, and that's when you get a dangerous movement conflict. It's the same reason we only say "cleared" in relation to flight plan, landing and takeoff, you are never "cleared to taxi" unless someone is doing it wrong (i.e. cleared generally means you get use of the runway).

Wait is very much a command pilots know and use, for decades, unless they've never flown outside North America. In which case they should have superlative English anyway.

Edited February 21, 20224 yr by ckyliu

It was best when I was able to say "taxi into position and hold."  Everyone liked that and it was very clear - never had pilots confused about the phraseology.  And no one has perfect phraseology all the time on the controller side, US, UK, EUR etc.  We all try and occasionally make mistakes.  In fact people listening to air traffic in the US might mistake what they think to be a phraseology error to actually be acceptable.  In the US I must first use proper phraseology - but if a pilot is not understanding something I can use plain language.