The Norden Bomb Sight manual

CALIBRA-

TION ME

SIGHT

N.O.P.

#650

pg. 17-36

Fig. 59

Fig.6c

Fig.

SECTION X

CALIBRATION

Before trying

to calibrate

any kind of precis-

ion instrument,

it seems logical to presume that

unless

the tools, jigs, and

measuring devices to

be used

themselves in proper calibration,

nothing will be gained by wasting time using them.

Therefore,

the calibration outline starts not with

adjustment of instruments

but with the proper

methods for checking and adjusting

the auxiliary

equipment and its proper care.

The

Instructor will perform each

step in cali-

bration

and discuss it thoroughly before the stu-

dents will proceed with calibration. Check the

work of each student.

A. SET PEDESTAL REFERENCE INDEX.

2: Binstall staze an healizet do not drop

sight into sight stem sieeve, and connect bomb-

sight connecting rod to stabilized sector. Insert

Turn head of stand until point of inter-

section of cross hairs will track, as

search knob

is used,

parallel to any grid line,

and clamp

head of

stand.

Loosen

pedestal reference index plate, and

index with closest index on head of stand.

Tighten screws in plate.

B. ESTABLISH GRID LINES ON TRUE HEADING.

1.

vark line on floor along any true heading.

A true heading in Bida. 379 can

using a

triangle which

is properly marked

in ref-

erence to the

rectangles on the floor).

2.

Turn base of stand (sight must be left at

zero drift and pedestal index left matched)

point of intersection of cross hairs

will track,

as

search knob

is used, parallel to line on floor. j

OF VERTICAL HAIR.

a dot on sheet of paper and

lay the

paper

the

vertical

stanchair on dot.

on the floor about 8 feet from

the base of

Turn head

of stand or sight to set

standair on dot. If vertical hair cuts across

2.

sight

on

stabilizer

(do

drop

align

course

centering

marks

pointer,

and

rod

to

5.

be

established

by

until

hair

on

dot.

If

vertical

hair

cuts

across