First thing I would do is check there are any sizeable landing fields within gliding distance of the aerobatic box, before flying your manoeuvres.
It must be a club aircraft, as no-one would own a C150 who is interested in aerobatics, there are Extras and Pitts available.
Most aircraft instruments have some sticktion, and can move in jerks. Gliders are especially prone to it, as there is no engine vibration.. To get a reading you sometimes need to tap the instrument panel.
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