Agree with all the comments made so far.
But, to go off on a slight tangent:
When I was in the States, I was discussing overhead joins with some American friends. They saw the advantages of the overhead join, but pointed out that it adds a few minutes to the time it takes to join, as compared to the 45-degree entry they use. But I think, overall, we agreed that the overhead join was better - it gives you a chance to check out the airfield if you're unfamiliar with it, and, most important, have a good lookout for traffic.
Then they asked an interesting question: "How does the overhead join work if you have parallel runways? There'd be traffic flying patterns (circuits) on both sides of the field." Gulp! The idea of parallel runways at a GA field, let alone an uncontrolled field, had never occured to me before I started flying in the USA - but it's quite common over there. The field I was based at had parallel runways (ATC during the day, but uncontrolled after 9pm) with circuits on both sides of the field. 5 miles away was another GA field, with 3 parallel runways. And I also flew into a completely uncontrolled airfield with parallel runways once.
Is this a key factor in why they don't do overhead joins there, I wonder?
Discuss.....
FFF
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