FFF
Our views seem closer.
I do agree that the real point of the exercise is for the reasons you now outline.
However, as you go on to say, the object is also to enable the student to feel confident about repeating the exercise once he has his license as part of remaining current. When he does so the instructor will no longer be with him. New PPLs make mistakes. (So do old ones!). For that reason I maintain if you are doing 360 a HASELL is a useful check, if for no other reason than it emphasizes the need for a good look around before commencing, it ensures the pilot will have remembered to check the airframe is clean and given that he might just get into a spiral, he has got height on his side.
In short I would still come back to my original point - why not teach the student to do a HASELL.
A 90 degree avoiding turn I agree is something different and I can accept the justification for "surprising" the student with a few of these - no HASELL check before - but with the instructor having performed a good look out first. However, I don’t think this is what instructors do on the whole - it is the old show me a couple of tight turns please, and the student wheels it round somewhere between 320 and 400 degrees!
I agree the comparison with an aileron roll may not be entirely justified if only because the outcome could arguably be less predictable than a tight turn. However, I would always want to check there was no one around before commencing a tight turn, if for no other reason than I have not got eyes in the back of my head. However for a well executed aileron roll I am doing nothing different than continuing straight and "level" albeit the aircraft is up side down for a moment.
Say it again
"Whether the turn is through 90 deg. or 360 isn't really relevant to the discussion."
I think you have missed the point of the discussion on this occasion.
DFC
"Doing a long detailed HASEll check means"
Can see you have never done one then.
"You are converging with an aircraft on your right at the same level and do not spot the aircraft that you are required to give way to until it is too late to turn behind. The other pilot maintains heading and speed. You complete a steep left turn through 360deg or slightly less and pass behind the other aircraft. Thus while not an ideal situation you manage to comply with the rules of the air for converging traffic."
I can see us all doing that then!
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