There is no requirement to hold a constant level of acceleration or
level flight. The requirement is simply that the weight vector be into
the seat at 1 G. It is possible to take the airplane through a 360 roll
about its axis doing this, so such a flight pattern would NOT be
noticed by a blindfolded with hearing blocked PX. I do appreciate the
airplane will not end the manouver straight and level and will not have
its initial heading. Recovering those values may be physically
impossible -- it will be going down pretty fast, and I can't imagine a
flight path that take the airplane back to S&L without inducing more
than 1 G on the cockpit. The question I have is, does an airplane exist
that has the control authority to fly such a roll?



On Jan 2, 4:13 pm, Mxsmanic wrote:
It's possible to execute a roll with the acceleration vector
continuously pointing in the proper direction and with continuous
positive G forces, but it is not possible to do it with a constant
level of acceleration. That is, you can keep the acceleration
positive, but you cannot hold it at 1.0 Gs. As long as it is positive
and the vector is stationary (both of which are possible), passengers
will have only the sensation of slightly rising or falling in a
straight line during the roll.

I've seen Bob Hoover demonstrate this by pouring fruit juice into a
cup during a barrel roll. Others have probably done the same thing.

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