Climb "TO", descend "TO"...........

[Silver Fox]

I posted this a while back in "African Forum" with no reply, so here goes. Any input appreciated, thanks.

This is probably directed at any of the helpful ATCs out there in South Africa. I notice the insistence on using the terminology "climb TO or descend TO..." in your airspace. While I have no problem with a descent/climb to a flight level, the same cannot be said for an altitude, eg. "descend TO 8000 feet, QNH..." The dangers of confusing 8000 with 28000 feet are well documented, so I will not elaborate. I also notice that this terminology is not used in Europe, and to the best of my knowledge, anywhere else. Please confirm that you are conforming to ICAO regs, or the local SA regs. Do any other drivers out there have any input?

Thanks in advance, off to the beach...
SF


------------------

[Bagheera]

Silver Fox,
Cant help with the SA issue, what I do know is over here it is hammered into us from day one that when it is an FL you use "climb/descend" only...if it is an altitude it has to be "climb/descend to altitude"..The theory being not only do you have a distinction in the phraseology but that the word "to" is never spoken alongside the figures required.
God help the student that gets this wrong...at the very least they can expect a severe dressing down...a practice that keeps us safe once operational

[375ml]

Oz procedures describe the following phraseology:

1. Description of levels ("(level)")
a) "FLIGHT LEVEL (number)" or
b) "(number) FEET"

2. Level changes and rates
a) "CLIMB" or "DESCEND" followed as necessary by:
i) "TO (level)"
ii) "TO AND MAINTAIN (level)"
....
e) "CONTINUE CLIMB (or DESCENT) TO [AND MAINTAIN] (level)"
....
....
4. Use of block levels
b) "CLEARED BLOCK (level) TO (level)"

and so on

The transition altitude is A100, so the possibility for confusion with "CLIMB TO EIGHT THOUSAND ... " vs "CLIMB TWO EIGHT THOUSAND" is remote.

SF: do you have a reference for documentation on the dangers of confusing 8000 and 28,000ft? Are there FIRs where the transition altitude can get as high as 28,000? Or is the issue not as simple as I've put it -- ie 'there is no such thing as an altitude above the transition layer, therefore a pilot would question such a clearance'?



------------------

[identnospeed]

Exchange with a pilot on a carrier where transition altitude in the pilot's home country is around 18-20,000ft.Climbing out of Gatwick (LondonTMA transition alt = 6000).

ATCO "*** climb to 6000ft "

Pilot " OK, here we go ! 26,000 we're climbing"

ATCO "err...just confirm thats a cleared altitude 6000 ft"

Pilot "oh....OK we're stopping at 6000"

This type of response has even occurred when the words "climb TO altitude 6000", but using "TO" altitude is correct phraseology and reduces chances of error.

[Wedding Tackle]

Kuala Lumpur, 18 Feb 1989:

(Tiger 66 is a Flying Tiger Lines B747 freighter.KL Radar is out of service-procedural)

ATC: Tiger 66, descend to/two four zero zero, cleared to NDB approach RWY 33[NDB/LOC]

F/O: NDB, that son of a bitch

CAPT: OK, four zero zero...alright go ahead and I'll set you up...

About a zillion human factors issues came out of this one (trans meridian travel and crew rest, no prebriefing [plates not ready], incorrect NOTAMS [ILS out of service], GPWS ignored, ambiguous approach plate frequencies etc)

But, if ATC said: 'Tiger 66, descend to two thousand four hundred [feet], cleared...'
AND/OR
Queried the incorrect readback, the crew would probably be alive today and the fires from their burning aircraft wouldn't have lit up the hill upon which the KL LOC is situated (aircraft and cargo burned for days).

Food for thought-It is acknowledged that the crew was fatigued but how many instrument approaches start at 400ft-NIL. Most MINIMA for non precision approaches are over 400ft.

[karrank]

Omitting the "to" can cause confusion too.

Aircraft at 10,000'.

"Descend 8,000."

Aircraft descends 8,000' and levels off at 2,000', which is bad.

I recognise the other problem though, and try to enunciate the level clearly separate from the "to".

------------------
"Cut him off and call him shorty!" - Lorenna Bobbit (Patron Saint of ATC)
------------------

[tired]

karrank

That's pushing the bounds of probability a bit, isn't it?? The scenario you describe has never even crossed my mind, nor have I heard anyone else allude to anything like it in 20 years of flying. Am I living a sheltered life??!!

[RTB RFN]

My personal opinion is that I would prefer the word "to" never to be used prior to other numbers. However, the most important aspect of this arguement is international standardisation. The Flying Tiger accident, again, imposed a reaction to implement a change, a change which in itself is fraught with other ambiguities and hazards for disaster. For twenty years I didn't say "to" - never had a problem.

[Silver Fox]

Thanks for all the constructive posts folks, and I think RTB RFN hits the nail on the head, calling for a global standardisation. Now that would be nice. I have to agree that hearing the word "to" followed immediately by a number makes me a little nervous. Especially in Africa. I was hoping for a reply from an SA ATCO, perhaps they can shed some light on the matter.

Off to the beach...............SF

------------------

[V1 Rotate]

Silver Fox,
I know that it is amazing that they use such strange terminoligy, but you only hear it in Durban Airspace. I have never heard it anywhere else in the World. Those of us who fly into Durban Know that the "2" prefix is not part of the numerical clearance and ignor it but it must be confusing to newcommers. I don't think that the Durban airspace is busy enough for it to constitute a danger.

[tired]

V1 Rotate

Afraid not, squire. I operated into FAJS 10 days ago and both the Area and the Radar controller used "to" on every clearance. On the way out a day or 2 later, the Area controller did the same, though Radar didn't.

[V1 Rotate]

Tired,
I guess you are right. Your reply just serves to highlight the lack of standardization from ATNS. Why can't they just stick 2 ICAO standards. I also believe that they are very short staffed at the moment. Any comments on the short staffing anyone??
V1 Rotate

[APP Radar]

In Portugal and almost everywhere in Europe, Transition Altitude is bellow 10.000 ft so it's not likely to have a descend/climb clearance to two thousand feet (to 2000) confused with two two thousand feet (22000).

[Capt Pit Bull]

I'll have to drop by the CAA library and check the manual of air traffic services, but is it not the case that 'to' should never be folowed by a number?

Although 'to' is used in vertical clearances, I thought that the word 'Altitude', 'Flight Level' or 'Height' was always suppose to be used.

e.g. 'to 4,000' might be dodgy, but 'to altitude 4,000' ought to be bombproof (as well as repeatedly ramming the fact that you are now on QNH down your throat, in case you've screwed that as well).

CPB

[need to know]

On occasion I've heard the word "till" used in an altitude/flight level instruction. It can avoid confusion particularly if concened with non english speakers...

------------------
And that's what I think about that.

[FooFighter]

The "TO" problem also has an impact on speed control (assuming that your airport has no automatic speed control points on the approach plates etc). If your transmission clips, some very strange readbacks occur - I've had requests to confirm "216 knots".

For climb and descent, remembering to include the "type of level" eg "descend to ALTITUDE xxxx feet" should prevent problems (I say "should"...) I appreciate this might just be a UK MATS thing.

=======
The Foo

[The Ant]

For those who operate in south african airspace, it has been published that the 'TO' will be used! We might not agree with this, but the SA regulations state the usage thereof and ATC will therefore expect you to readback in the same manner. This issue being a safety issue needs to be resolved in some other way, but remember by not reading back the correct phraseology as used in the country of origin indicates your lack of flight preparation and an unfamiliarity with local AIP's and AIC's. I do know that the boss at ATNS in South Africa is very much an old school type of individual and has laid down very rigid and inflexible operating criteria for the ATCOs. Hence the frustrating separations used by the ATCOs around South Africa. In the time it takes a controller at Johannesburg to get an aircraft airborne, Miami or New York would have landed two, got three airborne and allowed a C172 through the circuit!!!

[RTB RFN]

The Ant

Yes, Australia has gone very much the same way.

Backwards in terms of expedition and the complexity of never ending phaseology changes and additions and the ludicrous readback requirements have taken almost all commonsense and initiative out of the game. I believe that most changes are based upon standardization which, when applied with intelligence, can be good. The problem remains that when the project managers are a career self interest group of one the change becomes one for personal gain not that in the interest of the industry. We also predominate with standardization to ICAO instead of being bright enough to assess the impact, judge the value and maybe even, for once, shake off the sheep image and design a better procedure for change. Frustrated - Yep. Give up - NEVER

Be still my heart - it's only love....no wait it's flight!

[tired]

The Ant,

Thanks for the reply,it explains the differences.

I must take issue with your comment that a lack of knowledge of the host country's AIP and AIC indicates a lack of preparedness and flight preparation. This is an attitude that has annoyed me with SA ATCOs for years (I am South African, now working overseas, but the 1st 20 years of my career were spent in SA.) You cannot seriously expect a longhaul pilot to be familiar with the AICs and AIPs of every country to, and over, which he operates. In the last month I've landed in 6 different countries and have overflown about 20. How the hell am I expected to be conversant with each and everyone's regs?? That's why we're supposed to have internationally applied standards and that's why deviations from these standards, such as the one that started this thread, are threats to safety.

Maybe it's time the old school boss down there dragged himself into the 21st Century or took retirement.