Number 1, number 2, number 3...
 

So you are flying along in the circuit and have just turned base. There is one ahead on late final, one just turning final with you behind him. Another guy is mid downwind, so a pretty normal circuit at your local CTAF.

The guy in front's radio call says XXX turning final for 36 number 2 as there is one on late final. Then the guy turning downwind calls downwind for 36 number 3 because when aircraft 3 calls base he doesn't say "number 3." Yeah he made an error but everyone else doesn't know that.

How did the "number X" phraseology come about? I can't find any reference to it although I haven't looked very hard. Of course I realise ATC use it regularly such as at Moorabbin. Is the numbering system per leg of the circuit or per circuit?

I suspect it started in the CTAF with pilots using "number 2" to alert number 1 that they have them sighted and won't run over them. Problem is, it has progressed from there and where does it end and how should it be managed?

The aircraft on late final then lands and everyone's sequence number is less 1. Of course you aren't all going to give radio calls to update your number..... If people are relying on numbers higher than 2 then you are prone to potential disaster. See and avoid yeah yeah but it is potentially causing a false sense of security.

Thoughts?

You will find it in ERSA Local traffic regulations at some Aerodromes. Not standard phraseology at all non controlled aerodromes. Number 2 could also be used so the A/C ahead knows you are aware of him & cut down unnecessary calls.

Well it's silly, your example shows how it can break down with potentially fatal consequences if someone gets the number out of sequence.....

The number in the sequence is continually changing anyway so when it's busy how would you keep track?

Just make all the calls as per SOP, look outside the window and use AIRMANSHIP

leave the numbers for the tower controllers

A maximum of 2 feels like the best approach but then when number 3 turns final number 2 is thinking "has he seen me."

:ooh:

Rod Con, can you please tell us which aerodromes this applies to?

I've never heard of it and it just seems like a recipe for disaster.

Point Cook

I understand it was introduced by one flying school at Moorabbin after a mid-air collision. The habit seems to have caught on and rightly or wrongly, is now common practice. "Airmanship" has disappeared at some GA aerodromes where pilots rely blindly on radio calls rather than having a good look around watching for conflicting traffic. Plus the fact that lengthy and often superfluous cockpit checks means student pilots have heads in the cockpit during circuits rather than heads swivelling looking outside the cockpit :ugh:

Situational awareness...

Mangalore is another one.
Both Point Cook and Mangalore require the number only with the base and/or final call. Not downwind.
You should have a full picture of the circuit traffic by then but if there is any doubt, or you hear a call which appears wrong, speak up to clarify the situation.

Australia does it best :D

Its been standard practice at YMMB for about Ten years as far as I can tell.

I agree with KingRB it is for the controller (maybe CAGRS as well?) to designate your number in a circuit and may be lethally stupid to try and do it yourself and announce it to the world....or not.

I also don’t recall a controller at YMMB going past number three. I guess it is a bit academic after that and most pilots can't count past Five anyway unless in bare feet.

My personal limit at Moorabbin if I'm out doing circuits is about Six, depending on the quality of the radio transmissions I'm receiving and the behaviour of everyone else. When I hear in broken English of an imminent arrival from Sandown plus another at Parkmore, both requesting circuits on arrival, I make the next one a full stop.

Speaking of busy, I was at Moorabbin on Saturday. As soon as the sun came out after lunch it was crazy time. I counted 11 aircraft across the two runup bays alone.

The ground controller was going flat chat, gulf 2, alpha 4, blah blah. It used to be far less complex, you'd just rock up to the end of the runway and call when ready!

I believe Centaurus is correct. AFAIK it was introduced by GFS after the over-the-runway collision in which poor Holly Smith died.

It was not used during tower hours, but when the zone was MBZ (as it was then). Was intended to inform/warn pilots, particularly in darkness, if another pilot thought he was the same as you in the sequence.

Can't recall any mid-airs during non-Tower hours since, so maybe it is fulfilling its purpose ?

Pilot nominated position in pattern
 

Surely the calls "Joining/Turning Downwind Runway XX", "Turning Base Runway XX" and "Turning Finals Runway" should be sufficient with out complicating the issue by nominating your own "Number" in the pattern. As has been said, if that does not prompt anyone unsure of anothers position he/she should request clarification.

..cynical pilot!?

That narrows it down to pretty much...everybody..

I'll (very) occasionally use it as a kind of shorthand for "I've sighted you, and I'm going to follow you in" - usually for the jump plane doing a straight in approach to let him know he can have first go without clogging up the airwaves with a detailed call.

Simpler and quicker to say "ABC turning base, number 2 to the Cresco" or whatever following his call.

So unfortunately it's guilty as charged m'lud! :=

But I'll agree after #2 it becomes pretty stupid in a CTAF.

Simpler and quicker to say "ABC turning base, number 2 to the Cresco" or whatever following his call.


Number 22. Use "behind" or "following."

It was invented as protection in places that are far busier than your average CTAF but still towerless. Point Cook And Mangalore have more movements than almost any other ctaf in Victoria that I can think of with somewhere in the vicinity of 100 full time students at each, and calling the numbers is not just for the aircraft turning, but for the aircraft in front and behind. Someone calls number 1, when you know you are, " confirm you are number two" resolves it most of the time.. If not and you can't find the traffic, bug out.. Can't see the problem with it..

Number 9, Number 9, Number 9......