The Norden Bomb Sight manual

S. Mechan-

i cal Sol-

ution of

the Cross

Trail Pro-

biem M-4

and Up.

Fig 35

T. Forward

View

Mechan-

Ism M- E

7 degrees

38. In later models

the stabilizer hs three in-

stead of four mounting bolts.

39. The servo and telescope motors have 500 ohm

resisters wired in parallel. These prevent arc-

ing and burning of

the isolated sector brush and

telescope motor points.

40. In the later models

the sight stem has a stop

pin which limits the rotation of the sight at 32°

in each direction.

When the trail is set in on the trail arm,

the cross trail rack is moved towards the front of

the sight by means of a pinion

gear which is

mounted on the trail arm pivot.

The forward move-

ment of the cross

trail rack is transmitted

through a bell-crank and a linkage system

to the

yoke.

Due to the action of the bell-crank, the

yoke

is moved to the rear.

Since the yoke en-

circles the disc, upon which the stud is attached,

the disc and stud are both moved

to the rear of

the sight stem a

distance proportional to trail.

When the correction

for drift is made, the stab-

ilizer is turned under the sight, thereby

causing

the dovetail to swing through an arc relative to

the

fore

and aft axis of the sight.

Since the

disc and

stud

are

eccentric to the center of the

sight stem, the stud will travel through an arc

relative to the

bombsight.

Because the stud is

engaged in a slot in the cross

trail carriage, the

angular movement of the stud is translated

linear movement of the cross

trail carriage.

The

movement of the

carriage is,

in

turn,

transmitted

through

beli-crank and the differential lever

The cradle is then tilted through

an angle which will cause the optics to subtend

cross trail distance on the ground.

On the M-6,

early models, the forward view

mechanism

consisted of an auxiliary search knob

geared to the cable operating

sheave. which is

geared to the telescope quadrant.

Seven

degrees

be added to the sighting

angle making a total of 77° sighting angle.

extra degrees of sighting angle

can be

set in

only when

telescope quadrant is at

maximum

sighting

angle.

the telescope quad-

rant is

at maximum position

tue camway follower

stud

is

at the end of the camway.

The camway

nas an

shape projection, and when

the auxiliary

search

knob is rotated

the shape projection