Originally Posted by
sycamore
When teaching students to do `barrel-rolls`,I used a simple `tool`to demonstrate the key positions to reach during the manoeuvre....the spiral bound `toilet-roll/kitchen /paper roll`insert,,,,each may have a different `degree of spiral`,and can therefore show all combinations of large or tight `loaded rolls.`
Then draw little aircraft `symbols` along the `spiral`,whether left,or right spiral,at each 90* point around the spiral.
It should be noted that the `barrel` has `width`,and the centre of the roll axis is displaced out from the`nearest` display`foul-line`,and that the aircraft will be commencing the roll at an `offset` angle of maybe 30-60 *..
Having drawn our roll,,you now look though the`tube and align the centre with the horizon,and note the positions/attitudes of the `symbols`at the 5 critical points,bottom,mid-climb,top,mid-descent,bottom ,at end.
The most `critical point is at the `top` of the arc`,nose above the horizon,wings level(late,and you maybe in trouble..).Now tilt the roll down,and see the difference it makes to the 2nd half of the roll; you will be lower,maybe faster,need to roll faster,and reduce the `pull to escape`....
So,my mantra was`Always above..seldom level..never below`(the horizon),,for the roll axis...and never multiple rolls,,unless you are pointing `up`...
Just to be clear; what you have described works perfectly well in the teaching of normal acro. In fact, my own pedagogy teaching barrel rolls isn't all that different.
Teaching barrel rolls in the classic sense and style is a world apart from the low altitude air show environment where show lines, min and max altitudes and most importantly energy state entering into and at egress are all pertinent factors present in the maneuver sequence requiring predetermined spacing and energy state as required for the next maneuver in the routine.
There is a TREMENDOUS difference between the air show aerobatic display environment and the environment used in the teaching of normal aerobatics.
One of the most difficult factors we find in transitioning aerobatic pilots into the airshow environment isn't found in the technical aspects involved with aerobatics per se' but rather in the required transition from the normal aerobatic environment into the highly specialized world of the display pilot.
It's a night and day comparison where what is normal as related to everyday acro can kill you in short order in the world of low altitude aerobatics.
These are just a few considerations in any and all ACE flight tests required here in the United States for any pilot wishing to obtain a card of competency as required to enter the air show industry as a display pilot.
Dudley Henriques