Stabilized sector and altitude knob
RESTRICTED
B. Stabi-
lized
Sector
Fig. 31
C. Altit-
ude Knob
Assembly
N. O.P.
#649
if tre drift knee is turned the critt worm
rotates the drift gear which wil! disclace the
stabilized brush giving a readine on the PD!.
When both knobs
are rotated at once it is
called double gripping.
set up the course
properly the knobs may
be double
cripped.
must be remembered that the auto-pilot clutch is
a slip connection
between the directional gyro
and the stabilized PDi brush, and
that unless
the auto-pilot clutch is dis-engaged the PD! brush
will be displaced when the course knobs are rotat-
ed.
the bombsicht clutch encaged and the
auto-pilot clutch disengaged
. the PDI brush
displaced
the sight wi!! rotate in azimuth
as the course knobs are double grioped.
Over-correction factor is the amount the air-
plane is turned more than
the line of
sight while
double gripping.
The over-correction
acior or
the M-3 is 5 i/4. On, later units
it is 8 1/4.The
sight
turns lo
Ror Land
airplane
turns
61/4° on the M-3 and 71/4° on the M-6.
The stabilized sector is the
gear connection
between the sight and the sight clutch connecting
The stabilized sector
a part of
bombsiaht.
Beigo so,
when it is stabilized in
azimuth
(it is stabilized by the stabilizer gyro
through the sight clutch connecting rod, the en-
tire bombsight case is also stabilized in
azimuth.
The altitude knob assembly is composed of an
outer knob calibrated in revolutions of disc speed
and in feet of
altitude
on some units.
This
outer
knob is removable.
There are two altitude springs
and two cases.
The cuter
spring supplies the ten-
only when high disc speeds are necessary, as in
1 oW
the
altitude bombing;
the inner spring supplies
tension
for low disc speed used in high
a i -
but its
tension
employed,
titude bombind for high dise speeds
is always being
in which case
spring commences to add
its tension to
that of the inner spring.
These springs translate
their torque through the altitude shaft to
breaker arm.
This torque keeps the contact points
closed until the tension of
the altitude springs
is overcome by the telescope motor governor. The
65