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GLIDER 90
7th Mar 2019, 17:28
Evening All

When joining the circuit for the active runway to land, and approaching from non-active side of the pattern that is deadside why should we call this Upwind as when departing the active runway for a circuit or departing the field this is called Upwind?

2 sheds
10th Mar 2019, 14:41
Glider 90 - I am not quite certain from your phrasing the precise point that you are querying, but the following may be relevant, certainly in the UK. The standard circuit terminology is published in CAP 413 (UK), which is derived from ICAO PANS-ATM. Each is a masterpiece of inadequate terminology insofar as no designations are given to the first two legs of a circuit immediately after departure. Common practice in ATC training is to use the terms "climb-out" and "crosswind" respectively and but there is no formal authority for this. Also, CAP 413 uses the dreadful expression (in the text) of "upwind threshold" instead of "end" - a runway direction has one threshold and one end! Hence, there can be no precise meaning for the term upwind, rather that it is a general term indicating that area relative to the runway-in-use. CAP 413 adds to the confusion by giving an example of traffic information being passed as G-CD, traffic is a Cherokee upwind and a Tomahawk late downwind. Perhaps this is what you are querying. In this case, where is the pilot supposed to look for the Cherokee - on climb-out, crosswind or even at the start of the downwind leg before reaching the downwind report position? I have drawn this anomaly to the attention of CAA but am not holding my breath.

2 s

+TSRA
10th Mar 2019, 15:43
CAP 413 adds to the confusion by giving an example of traffic information being passed as G-CD, traffic is a Cherokee upwind and a Tomahawk late downwind. Perhaps this is what you are querying. In this case, where is the pilot supposed to look for the Tomahawk - on climb-out, crosswind or even at the start of the downwind leg before reaching the downwind report position? I have drawn this anomaly to the attention of CAA but am not holding my breath.

I'll start my Sunday morning a little cheeky; I think you meant where is the Cherokee in your example. The CAA might give a confused look at your query if you ask where the Tomahawk is and take that in the amused tone I send it. I agree though; there are some doozy terms in CAP 413.


When joining the circuit for the active runway to land, and approaching from non-active side of the pattern that is deadside why should we call this Upwind as when departing the active runway for a circuit or departing the field this is called Upwind?

As for the question, the answer depends upon where you learned your initial flight training and where you are flying.

This diagram describes what you learn in the UK (from CAP413):

https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/656x807/cap413_b863704147b0d9beacd34dc9d441039bca97179b.jpg



This diagram describes what you learn in Canada or the United States (from the FAA Aeronautical Information Manual as obtained from Air Facts (https://airfactsjournal.com/2017/04/where-is-the-upwind-leg/) with a notation from me about the wind direction):

https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/829x578/screen_shot_2017_03_31_at_5_12_32_pm_7f58d4e2c906cd081e6dfaf 1bbdf506ebba20ec1.png

So, depending on where you are geographical, either of the terms is correct.

In almost 20 years flying, I've found our beloved industry is notorious for people sharing and teaching their opinion of how things should be, rather than how they are. In this case, both terms are correct for different situations. Dead Side is not appropriate in Canada or the U.S, whereas upwind (or non-traffic side) is. Likewise, Upwind is not appropriate in the UK as Deadside is used to describe the same position.
It's akin to calling the landing gear the undercarriage. Some will pick a hill to die on over that debate! :)

It is simply a lack of knowledge, sometimes bordering on laxity, that comes from exposure; that is, most flight instructors train just in their jurisdiction so only know what they've been taught. Then, they get a student who either learned it a different way or is reading from a book published elsewhere, and that instructor will tell the student they are flat out wrong. The student is not wrong, given the proper context.

And a fact without context is just a belief.

GLIDER 90
10th Mar 2019, 18:03
+TSRA

You have answered my question with the UK have different terms for been in the circuit, compared to Canada & USA. Why don't they just make everything standard across the globe and this would erase any confusion!!

2 sheds
10th Mar 2019, 19:45
+TSRA

Very observant, thank you - I have corrected the aircraft type.
No, I didn't confuse the CAA; I merely queried the undefined (in ICAO and UK) term "upwind". And your comment is indeed taken as a ;-) !
You are quite right that many other states have there own variations or additions such as joining the downwind leg at a defined angle if the circuit is active, the specification of a mid-point position on the downwind leg etc.
However, as the OP is based in Lincolnshire, I assumed that he was talking UK procedures - and I made that clear. In the UK, use of the term upwind in this context is inappropriate because, as in ICAO, it is not defined and therefore can be misinterpreted.
The UK CAA really needs to address this subject - including the issue of direct joins on either base leg or crosswind, and whether under ATC, AFIS, AGCS or no radio service. After two fatal collisions in the circuit in recent years, the responsibility was essentially left with the aerodrome operator or ANSP, thus creating the probability of even more local variations with resultant confusion.
​​​​​​​Glider90 - couldn't agree more.

Cheers
2 s

chevvron
11th Mar 2019, 18:55
+TSR

The UK CAA really needs to address this subject - including the issue of direct joins on either base leg or crosswind, and whether under ATC, AFIS, AGCS or no radio service. After two fatal collisions in the circuit in recent years, the responsibility was essentially left with the aerodrome operator or ANSP, thus creating the probability of even more local variations with resultant confusion.



Cheers
2 s
Course if everybody phoned for PPR and briefing..........https://www.pprune.org/images/icons/46.gif​​​​​​​

2 sheds
12th Mar 2019, 15:21
Course if everybody phoned for PPR and briefing..........

Don't quite see the relevance of that observation. Surely the whole thrust of the above is advocating standardisation - unless you are introducing a note of levity in the context of fatalities?

2 s