barrel roll in 172

john smith wrote:

In article ,
Matt Whiting wrote:


When you are pulling negative G, there is no one natural G force. It
takes -1 G of acceleration to counter gravity and get you to 0 G. You
can then add -1.76 G of additional acceleration and still be within load
limits. The negative G load factor is referenced to 0 G, not 1 G
straight and level.


Is negative G an up force or a down force?

It is an acceleration opposite the normal acceleration due to gravity,
so it would be downward with respect to the airframe.

Matt

Matt Whiting wrote:

It is an acceleration opposite the normal acceleration due to gravity,
so it would be downward with respect to the airframe.

What about the case of a fighter jet climbing on afterburners at a steep
nose-high attitude quickly rolling forward through the horizon to a steep
nose-low attitude? Wouldn't the negative G force be considered an upward
force with respect to the airframe?


--
Peter

On Tue, 25 Jul 2006 18:21:54 -0400, "Peter R."
wrote in ::

Matt Whiting wrote:

It is an acceleration opposite the normal acceleration due to gravity,
so it would be downward with respect to the airframe.

What about the case of a fighter jet climbing on afterburners at a steep
nose-high attitude quickly rolling forward through the horizon to a steep
nose-low attitude? Wouldn't the negative G force be considered an upward
force with respect to the airframe?


Of course.