Instrument flying is really no different than visual flying except that when flying on instruments alone you are just shrinking the visual clues into a smaller picture.
It may help to rid your mind of thinking about control instruments and preformance instruments as well as primary and secondary instruments and just think of the flight instruments as one picture.
When I fly with reference to the instruments I do not "scan" so to speak, what my mind computes it the whole picture that it receives no matter where on the panel my eyes are focused. Peripheral vision will also give you clues to any diversion from the desired attitude. ( Probably the most important item for smooth accurate isnst. flying is proper use of trim.)
For instance whan flying straight and level at 3,000 feet or 30,000 feet if the altimiter needle shows 3,200 or 30,200 feet peripheral vision will alert you to the diversion.
We can get to involved in explinations and descriptive wording and make something relatively easy difficult.
Bear in mind I am referring to steam guages, the glass cockpit is another subject.
The longer you do it the easier it becomes, so try and make the learning process easy by using the least amount of wording to get the lesson taught.
P.S.
I am doing a ferry costing for a new customer, could one of you Brits give me the price of 100LL in the U.K.? Liters & pounds will be fine.
Thanks
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The hardest thing about flying is knowing when to say no.