However I would still expect the instructor to have had a jolly good look around to make sure the area was clear first - which doubtless you do.
Indeed - as for any turn. In the case of a high-wing aircraft, this would include raising the down-going wing before the turn to ensure the area you are turning into is clear - as for any turn. And I don't just look myself, I expect my students to look too.
I dont see how a 360 degree turn can be justified as a practice emergency avoidance response in itself?
I agree. I think the point of the exercise (and it is really just an exercise, not something which has a direct real-life use) is that the student should understand how the amount of back-pressure required increases as bank angle increases, the increased likelyhood of the stall, and the avoidance of and recovery from the spiral dive - all with the aim of ensuring that they don't kill themselves by trying it themselves after their license issue, getting into a spiral dive, and either over-speeding the airframe or the engine, or, worse, not recovering from the spiral dive at all.
(Incidentally, steep descending turns are also part of the exercise - and these do have relevance when doing PFLs: in appreciating the increased rate of descent as bank angle increases, and using this knowledge to a) keep turns shallow when short of height on a PFL, or b) fly steep descending turns as a means of loosing height if high.)
I think the comparison with the aileron roll is a bit unfair, for a number of reasons. Firstly, you say no negative g, which is true if it goes right - but I wouldn't try an aileron roll (especially as an aerobatic student, or with an aerobatic student if I was an aerobatic instructor) with loose objects, in case it goes wrong. Secondly, being upside-down is very disconcerting until you get used to it, even with only positive g, so lookout during the manoevre is quite likely to be non-existant for early aerobatics students. Also, rolls are most likely to be included in (or at least in training for) an aerobatic sequence which has lots of changes of direction, both vertical and lateral, and speed, so a HASELL check is definitely required. None of these apply to steep turns - except possibly for a slight disorientation due to increased g. But that's my personal view (and bear in mind that I'm not an experienced aerobatic pilot, so it's not a well informed view), I'll quite happily accept that your view might not be the same as mine!
FFF
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