Learning to fly, or thinking of learning? Post your questions, comments and experiences here

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By NewFlyer78
#1658226
Hi all,

A couple for questions for the week before Xmas!

1. When joining the overhead, where do I announce that I am in the overhead. Can I do this at any point in the overhead or does this call have to be made when I reach a certain point in the overhead circuit eg when crossing the threshold at 2000ft?

2. When I depart from a runway and the circuit direction is in the opposite direction to my en route direction, do I just carry straight on after takeoff and then turn en route once clear of the circuit? I suppose the alternative is to follow the circuit all the way round and then leave the circuit by extending the base leg. I just think the latter would be a waste of time?

Thanks.


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#1658231
1. in the Overhead
2. a) what is in the AIP/Guide/Airfield's guidance b) what they tell you on the radio (when ATC) c) what is common sense - as in climb ahead until clear of circuit and then on track as you suggested.
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By rikur_
#1658245
NewFlyer78 wrote:
2. When I depart from a runway and the circuit direction is in the opposite direction to my en route direction, do I just carry straight on after takeoff and then turn en route once clear of the circuit? I suppose the alternative is to follow the circuit all the way round and then leave the circuit by extending the base leg. I just think the latter would be a waste of time?

As FD has said, I think this depends on local circumstances. At a couple of the places I fly from I would effectively go around the circuit and depart on a base leg heading - but that's because in one case of a neighbouring airfield, and another case a built up area - but ordinarily, continue straight ahead until a sensible altitude, and then turn en-route
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By Irv Lee
#1658257
1 - CAP413 says
Maintain 2000ft above aerodrome elevation or 1000ft above promulagated circuit level (based on QNH from the nearest available source), and observe windsock and traffic. Keep aerodrome a suitable distance on the left of the aircraft. Report OVERHEAD. Include the appropriate runway if determined. If unable to ascertain the runway in use continue circling overhead.

I do wonder if they thought that through.... keep the AERODROME a suitable distance... on the left... Report overhead.
Doesn't help does it? It looks like you would report overhead 'at a suitable distance'. Also, you wouldn't keep the aerodrome on the left if you knew from radio calls or just by local procedures that there is a right hand circuit. I think everyone should consider the Sengupta Victoria Sponge method. Imagine a large (normally 2000' deep) circular Victoria Sponge cake on the airfield. Nibble your way along the outer edge of the top of the cake with the centre of the cake on the side of the aircraft nominated by circuit's left or right direction. If not known, use 'left' until you determine it. On passing the landing point below, call deadside descending and descend down the outside of the cake levelling off at the cream and jam layer.... etc etc
(thread discussion now turns to the fact that I said cream and jam, whether you do have both, what vertical order they are layered... etc)
mick w, Nick liked this
#1658262
I can't claim responsibility for this analogy, that's all Irv's work, but I have to say I rather like it! :D And not just because of the cake aspects. It's a fairly simple thing to follow. A lot of people don't seem to be able to understand how the OHJ is supposed to work.
Irv Lee liked this
#1658299
That’s made things clearer many thanks. My training airfield doesn’t have overhead joins so I’m a complete novice in this area. I’ve only done 1 overhead join with my instructor and next is solo Nav to another airfield so making sure I am fully prepped.

I’m confident I could do this without more lessons, just wanted to iron out a few details.

So to summarise.

I make the call to state I am in the overhead as soon as I am established in the 2000ft pattern regardless of my position I relation to the threshold.

When departing for a track which is opposite to circuit direction, I maintain a climb straight out until well clear of the ATZ and then turn onto my desired track unless NAP state otherwise.


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By Rob P
#1658461
We are missing the significant information on the level of ATSU at the aerodrome in question.

Rob P
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By David Wood
#1658630
It's a good question, @NewFlyer78 .

What you should remember at the outset is that the whole OHJ was designed in the day when few aircraft had radios and all airfields had signal-squares. Therefore the standard way of approaching an airfield was to fly over it at more than 2000' agl (in other words, outside of its ATZ vertically-speaking) so that you could look down upon it from above and determine runway in use, circuit direction etc.

Once you'd done that, you would then position yourself to descend into the ATZ (ie, enter the ATZ from above) but on the deadside (ie the safer side) to then join the circuit at circuit height (ie, the same height as everyone else) by passing over the upwind numbers on the runway in order to join cross-wind, which was considered to be the safest place; bearing in mind that few aircraft taking off would have the climb-performance to be at circuit height by the time that they passed the far end of the runway. That was the theory and, despite its many nay-sayers, it works just fine.

So, to your specific question: your first call should be:

"Tumbleweed Radio, G-ABCD, approaching from the [west] to join overhead." They may or may not acknowledge; they might well give you the runway in use and QFE. They might not answer at all.

When you are in the overhead (and it doesn't really matter precisely where you are so long as you are over the top of the ATZ) you say "G-ABCD, overhead, descending deadside". Then everyone knows where you are and what you're doing. Again, you may not get an acknowledgement.

Once you descend into the ATZ you are obliged to make all turns in the circuit direction. This, whilst sensible, presents all sorts of challenges to students as they struggle to position themselves such that they descend on the deadside in an appropriate wide turn. It just takes a bit of thought and practice walking around your living room with a bit of paper on the floor to represent the runway and the circuit direction. You can hold your arms out like an aeroplane if you want :D

Once you have joined the circuit and have turned downwind you call "G-ABCD, downwind to land".

As with all things, keep a very sharp look-out. Someone else may be joining overhead also.

To your second question about departing. Again, go back to first principles. All turns in the ATZ should be in the direction of the circuit. So, if the circuit is a left-hand circuit but you want to turn right then you have three alternatives:
1. follow the circuit round in order to either depart off the base-leg at circuit height or, as a variation, continue climbing in the circuit and, once above circuit traffic and only if safe, turn to depart from the overhead in the climb - both are acceptable.
2. climb out straight ahead until you are outside the ATZ (ie more than 2nm from the centre of the airfield) and then you can do what you like (assuming that you aren't in anyone else's airspace, of course).
3. state your intention to make a non-standard departure, in this case to the right. You aren't asking permission (because an a/g can't give that permission) but you are informing them and everyone else of what you intend to do. Some might argue that such behaviour would be slightly discourteous - and so it is probably the least favoured departure option. If you were considering it it would do no harm to ask at the desk as you book out and you can then ascertain how they would view such a departure. Good manners go a long way in aviation.

Finally, as has been mentioned, many airfields will have local noise-abatement procedures which you are expected to follow. After all, you are a visitor but they live with their neighbours there 7-days a week. Quite often these procedures may prohibit a non-standard departure. So check before you take-off.

Hope that helps.
Last edited by David Wood on Tue Dec 18, 2018 11:39 am, edited 1 time in total.
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By Irv Lee
#1658664
David Wood wrote:It's a good question, @NewFlyer78 .
... the standard way of approaching an airfield was to fly over it at more than 2000' agl (in other words, outside of its ATZ vertically-speaking)

It seems the advice changed 'sometime' as I am sure the 2000'agl was the official line before... but now it has 'or 1000' above circuit height' which can put it below 2000' for a few (or maybe even above for one circuit I can think of)... I have wondered if this change was discussed and deliberate, or simply lax rewording.
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By David Wood
#1658679
Irv Lee wrote: I have wondered if this change was discussed and deliberate, or simply lax rewording.

Probably the latter. After all, the underlying logic is that the initial approach to the overhead is made whilst remaining outside of the ATZ (above it), to only drop into the ATZ once he has the information that he would have obained visually from the overhead. If he were merely 1000' above circuit height then, with an 800' circuit, he'd be already in the ATZ as he approached the overhead.

I suspect that like a lot of these things, sloppy wording has crept in un-challenged or un-noticed.