Mk 227 (Nose Mechanical Impact) (Obsolete)

Bomb

Functioning

Armed condition

Fuzes used with

Arming time

Over-all length, inches

Body diameter, inches

Material

Tin-plated brass and alloy castings

General: This fuze is unique in American aviation ordnance in using centrifugal force as its arming device. The rotational velocity required to arm the fuze is acquired by the offset tail fins on the small bomb.

Operation: Two pairs of centrifugal detents are employed - one pair supporting the striker, and the second pair positioning the slider with the primer detonator out of line with the firing pin. At a rotational velocity of 1,500 r.p.m., the detent move out of the way, compressing their springs and allowing the slider freedom of movement. The slider is mounted with its center of gravity away from the axis of rotation; so, when the detents move out of the slider, centrifugal force carries the slider into line with the firing pin. Upon impact, the firing pin is driven into the primer detonator, initiating the explosive ac-tion.

Remarks: The Bomb Mk 34 and Fuze Mk 227 were designed for air-to-air bombing, but have not proved successful in this use. It has, however, had limited use against par-ked aircraft and was dropped for its nusiance value on night raids during the early stages of the war in the Pacific.

Figure 372. Nose Fuze Mk 227