General

This particular series of bombs was not satisfactory for war use and has been aban-doned, except for a few of these bombs which are used for target practice and training purposes. They are all of the same type and are intended for accompanying chart con-tains the essential data concerning the bombs of this series.

U.S. Army "Modified Mark" Series Bombs

Bombs

100-lb.
Mk I MIV

300-lb.
Mk I MII

600-lb.
Mk I MIII

1,100-lb.
Mk III MI

2,000-lb.
Mk III MI
& MIV

2,000-lb.
Mk I MV

Fuzes

Nose: M105

Tail: M106

Overall-length

47.2"

51.2"

63.0"

68.5"

135.8"

Wall thickness

0.16"

0.12"

0.2"

0.15"

0.50"

Wall material

Steel

Length of tail

8.5"

12.0"

14.0"

33.5"

49.2"

Material of tail

Sheet steel

Sheet steel with cast-
steel tail cone

Weight of tail

2,6#

6.1#

5.0#

55.0#

140.0#

Cast TNT

Charge/weight ratio

54.5%

52.0%

58.0%

55.3%

50.0%

52.4%

Body construction

Streamlined body formed by welding three
cast-steel sections together

Cast-steel
nose riveted to seamless steel tubing; rear not tapered

Seamless steel tubing

Tail construction

A cast-steel sleeve secured to body by a fin locking nut; four fins or vanes; internal box-type struts

Four vanes with bar struts, at-tached to body by screws

Four vanes riveted to tail cone; two sets of external bar struts to reinforce vanes; cone secured to flange on base plate

Construction of

Two U-shaped bar-steel eyebolts welded to body along longitudinal axis

Two U-shaped eyebolts on plates secured to body by cap screws

suspension

Type of suspension

Horizontal

Color and markings

Prior to March 11, 1942, these bombs would have been yellow all over with black manufacturer's markings; but since that date will be olive-drab with one-inch yellow bands around nose and base and 1 ¼-inch band around center of gravity.

Figure 256. Army "Modified Mark" Series Bombs