Bell OH-58A Technical Manual page 62

PROFILE
BL - BUTT LINE
FS - FUSELAGE STATION
WL - WATERLINE
BS - BOOM STATION (UNDERLINED)
Figure 4-9.
CENTER TAILROTOR BEARING HANGER.
TANGENCY POINT.
CONTOURS IN BOOM STATIONS ARE
CIRCLES.
RADIUS AT 182.405 IS 3.286". TAPER'
OF BOOM IS 0.02703" PER INCH. BOOM
STATION IS 90° TO HORIZ C BOOM.
Airframe Reference
TM 55-1520-228-BD
RADIUS AT 31.87 IS 7.3555"
Lines
A I R F R A M E
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