Why the last 5 years? Why not remind ME? I risk assess everything I do.
I don't like overhead joins because of my perception of risk and from personal experiences. :)

Answer this: You call "Overhead, joining for runway **" as you begin your descent. You realise your transmission was almost simulataneous with that of another pilot who calls exactly the same.

You have seen no other aircraft, apart from those already in the circuit. Where do you look and what do you do to prevent an accident?

Exactly. One must fit in with other aircraft in the circuit. A rigid point to actually fit in cannot possibly work on all occasions, especially if the "pattern is almost full". This is where the (level) deadside join has a big advantage, as I tried to put forward. The pilot extends upwind to pass behind traffic already downwind, where necessary.

I'd like to think we all do that.
Interesting point; all you know is where they're going, which is to turn towards the dead side. Here's another question: You call "Joining downwind" and hear another call: "Downwind". Now where is the other guy:

• Ahead of you or behind you? (People call downwind at very different places.)
• Is he inside or outside you? (We all know people have very different views of where the downwind leg should be.)
• Above you or below you? (Should be the same height, but not always true.)
• Is he just turning downwind from crosswind?
• Is he joining crosswind from outside the circuit, US style (not legal in the UK, but people do it.)

All you know is where they're going, which is to turn (if necessary) to some ill-defined idea of "downwind".

I'm not disagreeing with the risks of OHJ, but almost any join is likely to end up with potential ambiguity of where someone is and where they're going.

FREDA, thanks but my question wasn't for you...

However, an aircraft calling "Downwind" is normally already in the circuit and should have made previous calls, giving other pilots a clue of their presence. I'm not advocating joining downwind as an alternative; but putting forward the disadvantage(s) of an overhead join as opposed to a deadside join.

Two aircraft can have and will continue to appear in the overhead at the same time, while the pilots are not concentrating fully on lookout, due to workload. Both pilots will be looking for the airfield and sorting out their orientation, particularly if they are not familiar with it.

When joining overhead there is no legal requirement to make a previous call. It's obviously good airmanship to call up for airfield details in advance, but many don't bother, or don't have a radio (the latter being the whole point of the procedure).

As you say, aircraft should be at the same circuit height on the downwind leg. Also, they should be in level flight, not one descending over another, in each other's blind spots, as required by an overhead join.

After seeing a few near misses at this (and other) aerial choke points, I prefer to think of alternatives.

The scenario I posted previously was one where we came extremely close to another aircraft joining in the overhead; the other nearly took our tail off from behind. We (I was not flying the aircraft) had called up with a position report for airfield details and announced our intention to make an overhead join. As my pilot flying called "Joining overhead", another aircraft also called the same, whilst almost hitting us from behind and above, and at a 90 degree angle to our track. He then cut across in front of us as he was descending more rapidly. There was no time for us to take avoiding action as he crossed behind us; we were a very few metres from a mid air collision. He hadn't seen us; he was manoeuvring in 3D whilst perhaps over-concentrating on his join procedure at the expense of looking out and not building situational awareness.

A 2D manoeuvre is, from my risk assessment and experience, less risky, in a high workload situation. The military obviously agree.

All circuits to the south of the airfield at 700 ft. Please avoid the villages of Bubwith, Breighton and Wressle to the north-west and south-west respectively. Join on the south side of the airfield for base leg. Please be aware of the power cables on the western approach

Yes, the circuit height (or altitude) should be respected when entering (the beginning of) downwind. That's why I was taught to cut power after making the overhead call, to ensure a quick descent. After some marked experiences, mainly with helo's on training, I learned not to go direct from overhead (the signal square) to (beginning of) downwind, but rather to descend along the circuit, i.e. upwind and crosswind legs, and zigzag slightly so as to keep an eye on departing traffic below.

But again: this is beginner's talk.

Here we tend to work to a QFE, so it's height.