Where does a downwind join officially start?

[clearfinalsno1]

I was recently flying north towards my destination airfield whose ATC have an ATZ but no radar.

Lets say the runway runs east/west and the westerly runway was in use. I was instructed to report downwind left for r/w 27. As I reached this point and just before making the call I noticed another aircraft turning downwind left to right ahead of me. This aircraft was in the circuit and had just reached circuit height in the crosswind leg. I followed the aircraft along the downwind leg and completed the circuit, landing as normal.

On the ground the other pilot suggested I should have joined the downwind leg further west as this would have reduced the opportunity for conflict. I did not disagree, but in reality would still have only called downwind left 27 at the same point on the circuit rectangle. I was surprised ATC did not warn of the other aircraft in the circuit especially having no radar.

I have no argument with the other pilot or his logic, but my question to the forum is : was I wrong to route for a downwind join as I did? Should I have gone much further to the west ? If so how far is much further? Or was I ok to head directly to the start of the downwind leg, and the possibility of conflicts with traffic in the crosswind leg is just something to be wary of?

[Crash one]

I don't know if there is an official join point on downwind but I would aggree with the other pilot "join at an extended west downwind position, that way you would not be in a head on conflict with circuit traffic. (Noise abatement permitting)
If your instruction from ATC was (report) downwind, I don't think that means (join) at that point, rather "report once you are established there".
Perhaps an expert will put me right, but we have a similar circuit pattern, north of Edinburgh accepting similar directions of joining to 25/07.

Trevor.

[gcolyer]

Good question...

I personaly join where cross wind meets down wind. If i see conflicting traffic coming from the cross wind then I orbit in to the down wind. Mind you if there is a tower he/she should at least tell you of other traffic in the circuit. If it is FIS then I would expect/hope all pilots are making the relevant calls whilst in the circuit. This is one reason I like overhead joins.

FAA land also has a good method which is joining 45 degrees to down wind at the point where cross wind meets down wind. Usualy you get a good view of whats coming from cross wind at that angle and have time to either slow up or chuck a couple of turns in to buy some time.

[pumper_bob]

Was the other aircraft the only other circuit traffic? If so I think i would have asked for a left base join on initial contact. If that was refused, then i would have made a standard overhead join, at 1500'QFE, assuming a 1000' circuit. Descend dead side with a 180 left turn onto cross wind. I find its much easier to slot in with circuit traffic this way, and if the base call was refused then there must have been traffic? As far as the definition of the down wind leg goes, i think it starts at 45 degrees to the up-wind threshold? I hope in all the fuss and confusion you didnt forget to do a full BUMPFITCCH? Including a good long blast of carb heat?

[Hour Builder]

Originally Posted by pumper_bob

I think i would have asked for a left base join on initial contact. If that was refused, then i would have made a standard overhead join, at 1500'QFE, assuming a 1000' circuit.

Isn't a standard overhead join, 1000 feet above circuit height?

[tonyhalsall]

I think that with a few more hours under your belt and a bit more confidence you might challenge an instruction like that next time.
It is never good practice to join and make a ninety degree turn thus reducing visibility and options in a high work load area.
As others have suggested, a left base or over head re-join would have been a safer and more practical option. Alternatively, you may have considered extending out to to the West well beyond the circuit before making your ninety degree turn.
Personally, I would say that irrespective of any ATC instruction, you are the Commander of the aircraft and you should challenge any instruction which you may feel compromises the safety of your flight. If the instruction stands then it is down to you to apply your own safety margins (ie join from a more Westerley position). Any unusual manoevre which reduces your ability to see in the circuit is best avoided.
You probably learned a good lesson and probably won't forget it.

[pistongone]

Originally Posted by Hour Builder

Isn't a standard overhead join, 1000 feet above circuit height?

If you are joining from the south and the circuit is to the south, then at 1000' you would fly right through the down wind leg Surely 1500, 500' over the downwind leg and 500' within the vertical limit of the ATZ would be better

[dublinpilot]

Piston,

HourBuilder said 1000ft ABOVE circuit height....so he wouldn't be flying through the downwind leg.

It is also my understanding that a STANDARD overhead join is 1000ft above circuit height. An overhead join can be done at other heights, but it isnt a STANDARD one.

I could be wrong on this too.....I just seem to remember it from the CAA's VFR guide.

dp

[Mariner9]

Do you ever do overhead joins in Ireland dp?

I joined overhead at Birr, much to the resident microlighters amusement

[pistongone]

Early morning dyslexia!

Sorry hour builder, i wasn't reading your post correctly, you are right 1000' over circuit height is standard. I suppose I have just got used to coming in at 1500' to save time! I do also like to know that any passing planes not on frequency should be at least 500' over my head, that does seem to make sense to me, what are your thoughts on that?

[vancouv]

I would have thought downwind begins at the point it meets crosswind. So if you are in the circuit you climb out, turn crosswind and then turn downwind. Anything further out is outside the circuit, and therefore can't be downwind?

If ATC told me to report downwind, I would assume I can join it anyway I want, but would probably go for an extended downwind position as I don't fancy the idea of flying straight towards someone who is on crosswind. There doesn't seem to be anything implied in their instruction other than report when you are established. This happens all the time where I fly, although downwinds are quite unusual - crosswind and left base are common.

ATC are trying to be helpful by giving you a more expeditious join than overhead - if you don't want to do it then ask for something else. I would have thought they would warn you about other traffic in the circuit though.

[tmmorris]

Originally Posted by gcolyer

FAA land also has a good method which is joining 45 degrees to down wind at the point where cross wind meets down wind.

This is, strictly, illegal in the UK where 'all turns within the ATZ are to be made in the circuit direction' (it's somewhere in the ANO, no doubt bookworm will come along in a minute and tell us where!)

Tim

[gcolyer]

Originally Posted by tmmorris

This is, strictly, illegal in the UK where 'all turns within the ATZ are to be made in the circuit direction' (it's somewhere in the ANO, no doubt bookworm will come along in a minute and tell us where!)

Tim

The 45 degree turn in is not a turn whilst "in" the circuit it is your enterance to the circuit. Although I guess it is all down to an individuals interpretation.

[tmmorris]

I didn't say in the circuit, I said in the ATZ.

ANO Rules of the Air Rule 17 (Rules for avoiding aerial collisions):

(5) Flight in the vicinity of an aerodrome
Without prejudice to the provisions of rule 39, a flying machine, glider or airship while
flying in the vicinity of what the commander of the aircraft knows or ought reasonably to
know to be an aerodrome or moving on an aerodrome, shall unless, in the case of an
aerodrome having an air traffic control unit that unit otherwise authorises:
(a) conform to the pattern of traffic formed by other aircraft intending to land at that
aerodrome, or keep clear of the airspace in which the pattern is formed; and
(b) make all turns to the left unless ground signals otherwise indicate.

i.e. unless ground signals (or radio information?!) indicate a RH circuit is in force. Though I admit that 'the airspace in which the pattern is formed' is not necessarily coterminous with the ATZ, I suspect a court would interpret it as such, in the absence of any other definition.

Tim

[dublinpilot]

Do you ever do overhead joins in Ireland dp?

I joined overhead at Birr, much to the resident microlighters amusement

Yes we do, but there isn't anything very standard about them!

Not that many airfields insist on a particular joining method, so it's a case of just useing what you think is most appropriate. If you think a standard o/h join is the most appropriate then that is generally fine.

An obvious exception is Weston who have a non-standard overhead join. Or at least they did before they got their new class C airspace. I haven't been in since they got that, so things may have changed.

dp

[clearfinalsno1]

Thanks for all the replies (although those on overhead joins are getting off topic)

Tony halsal said

I think that with a few more hours under your belt and a bit more confidence you might challenge an instruction like that next time.

I have about 200 hours over 10 years and I usually am asked to report downwind at my home airfield, an International airport in class D controlled airspace.

Nevertheless, the question still remains, if I had aligned with the downwind leg even 5 miles from the runway, I would still normally only call downwind left at the point where the crosswind leg meets the downwind leg. i.e. when the threshold of the reciprocal runway is at about 45 degrees when viewed from the cockpit window. This would still allow a potential collision with the crosswind climbing aircraft appearing to my left rather than in front of me. Other than actually seeing me approaching from the right, this aircraft climbing into the circuit would not know of my presence until I called "downwind left" at which point he could collide.

So we still come back to the issue that at this airfield and other similar ones, the ATC service is analogous to a FIS. It's still up to all of us to keep a VERY good look out.

Of course this entire thread could be repeated for base joins ie aircraft routing towards left base and reporting "left base" on arrival, risk collision with aircraft completing their downwind leg.

Finally, tmmorris's quote from the ANO was interesting. I didn't know about all turns being to the left.

[vancouv]

Unless you've switched frequency the plane in the circuit will have heard you call for joining instructions and that you were told to report downwind, so he should have a pretty good idea of your whereabouts.

If you joined the frequency after that planes last call you might not be aware of his position, but there's a pretty good chance you would have heard him being cleared for a touch-and-go and know he's in potential conflict with you. So hopefully it's not quite a s bad as you make out.

And I think unless you are flying IFR or have a radar service then it's 'see and avoid' even if you are talking to an ATC unit with radar.

[waldopepper42]

Originally Posted by clearfinalsno1

I would still normally only call downwind left at the point where the crosswind leg meets the downwind leg. i.e. when the threshold of the reciprocal runway is at about 45 degrees when viewed from the cockpit window.

Hmm, interesting. I was taught to call downwind when passing abeam the threshold of the reciprocal runway. Is this wrong?

Incidentally, if I was approaching at 90 degrees to the downwind leg, I would always request a base leg join or, if not practical for any reason, reposition to something nearer to the downwind direction whilst still outside the ATZ.

Doesn't apply if I'm under radar control, of course - then I do what the hell they tell me!

[J.A.F.O.]

Originally Posted by waldopepper42

Hmm, interesting. I was taught to call downwind when passing abeam the threshold of the reciprocal runway. Is this wrong?

That's my understanding too, Waldo.

A lot of other stuff in Pumper's reply confused me too, but that's easily done.

As to all turns in the ATZ in circuit direction - I know you're right but if I'm approaching from the south to join 27 lefthand downwind then how do I turn from 000 to 090 without doing a right turn? Not challenging what Tim said but genuinely asking how to do it.

[foxmoth]

OK a number of points here, yes Downwind call should be abeam the downwind end of the R/W (or when passing abeam the threshold of the reciprocal runway, which is the same thing). Turns should be in the same direction as circuit direction, and to avoid turning against circuit direction you should therefore be outside the ATZ before you turn right to position downwind, though it is permissable to join as descibed by turning against the circuit direction with ATC clearance, but when joining you should always be giving way to any established circuit traffic so clearedfinals should have been giving way to the guy already in the circuit. As said before, best way would have been to go for either an overhead join (and though it would be as well to state this, he just needed to call when finally downwind) or to ask for a L base join.
Note also that asking you to call downwind is not a clearance to join downwind so it should be queried.