The Norden Bomb Sight manual

B. Incorrect

Speed of

Drive of

Telescope

Quadrant.

C. The Pos-

ition of the

Transverse

Hair is Out

of Relation-

ship to the

Position of

the Telescope

Quadrant.

This can occur if the unit is properly

calibrated or

i t

can occur because the unit is

improperiy calibrated.

If the former, it is the

operator's fault: he has failed to use his rate

correctly and

not synchronized. Thus, he will

use either too

much or too littie

and there-

fore the rate

quadrant

will ziso be

rate incorrectly

positioned.

If he puts in too much rate, not only

wi!| the

telescope quadrant drive

fast but

quadrant will be posit. cred down-

ward too close to the

telescope cuacrant,

errors causing, by cumulative effect.

early re-

lease. Just

the opposite is true for too little

2. How miscalibration can cause too fast or

too slow a rate of

drive of the optics,

that is,

of the telescope

quadrant, will be seen

from point

"C" beiow.

The important

thing

remember is that

incorrect speed of drive of the

telescope quadrant

never exist

a lone; 1t

is always accompanied by

the error in

or "B".

The transverse hair should be at vertical

the telescope quadrant is at zero.

it be,

say, 30 forward of vertical, then if the sighting

angle happens

to be 40°

the

telescope

quadrant

will be positioned at 370.

the

telescope quadrant would-have to move only 37°frem

initiol

position in

order that

the transverse

hair, which

begins 3º forward of

a target 400

away. If the

actual sighting

angle be 40°

then of

course the

telescope quadrant

should then

be at 40°

erroneous position of the quadrant (notice that the

optics

cannot be said to be at an erroneous posi-

because

sighting

they have to be open to the

angle to

rest upon

the target) causes too

early a

for. two reasons:

the telescope quadrant is positioned 30 too close

1.

incorrectly

tcc

also

both

an

rater

to

If

its

zero

vertical,

This

tion

true