Gyroscopic Attitude Control Systems

Juergen Kirsch writes of the destructive potential of the gyroscopic
control system.

Frankly, who ever wrote up that idea for traveller didn't think about it
for too long.

The Starship Operators manual says these things are used at speeds
approaching 1 million RPM.  Ok, lets assume a gyro 1 meter in radius, and
say 1000 kilograms.  (sound reasonable?)
The centifugal force felt at the edge of this ring (1 million RPM) is some
thing about 11 billion+ times the force of gravity.
Nothing, Not even an ancient artifact will hold up to that.
Ok, Now, what about the potential energy of this gyro?  Well, according
to the old back of the envelope it has the equivalent energy of a
1.22 kiloton bomb.  According to the S.O.M. these things are kept at
"near" vacuum, at the center of mass of the ship.
	Well, who out there wants a 1.22 kiloton bomb at the spine of
their ship?  The manual talks about the extensive precautions needed to
protect the ship from the gyro.  Jettison systems, and an 'Inertial
Braking system' which reduces the energy of the gyro.
The precautions sound shakey at best and wrecklessly dangerous at worst.
If the gyro started to have problems, It would be a danger to the ship in
1/100,000 of a second.  No Warning.  If a frictionless bearing started to
go out, it would tear itself to ribbons before the computer ever knew what
hit it.  And when that gyro hits a structural member it will fly apart
under 11 billion G's and destroy the ship totally.  The center of mass of the
ship is going to be where the spinal mount (if any) runs, and it will
probably be where the keel of the ship runs as well.  One little mishap
and your ship snaps in half.
	As to the advantages of the gyro.  Frankly, I don't see any.
They have gone to great lengths in the Manual to describe how the
thrust from the main drive is articulated sufficiently so that the
classic 1G ship can take off vertically.  Are they trying to say that
turning on axis is more difficult than hovering?  It makes no sence.

Add to the fact that the gyro is at the center of mass of the ship.
In order to turn the ship you will have to exert enourmous force on
the gyro.  The thrusters have a much larger lever arm and it will be
MUCH easier.  The problem is analogous to turning a bolt with your
bare hands and turning the same bolt with a twenty meter long
wrench.

Looking back on what I said, computers ought to be fast enough to recognize
a problem in the gyro.  But they won't be able to do much about it, and if
something goes wrong with the safety systems, you are DEAD.  A braking system
has to absorb 1.22 kilotons worth of energy to prevent disaster.

Scott Kellogg

Actually, I don't like the sound of the inertial braking system either,
It makes it sound as though it absorbs the inertia.  This sounds to much
like a physics nullifier to me.  I always thought of inertial compensators
as grav plates which increase or decrease in output dependant upon the
acceleration produced by the drives.

Mr. Scott