|
|
| U.S.N.B.D. - ROCKETS AND FUZES |
| ROCKET FUZES |
|
ROCKET USED IN |
Mk 137 Mod 0, 1 and 2: |
U.S. NAVY NOSE FUZES |
|
|
|
4.5" High Explosive Barrage | ||
|
|
Rocket (Mk 3 head and |
Mk
137 |
Mk 145 |
|
|
Mk 5 head); | ||
|
|
7.2" Demolition Rocket | ||
|
|
(Mk 9 head); | ||
|
|
7.2" Chemical Rocket |
Air Arming, Impact Firing, |
|
|
|
(Mk 7 head) |
Rocket Propelled |
|
|
|
Mk 145: 4.5" H.E. Barrage | ||
|
|
Rocket (Mk 3 head) | ||
|
FUNCTIONING |
Mk 137 - Instant. Impact | ||
|
|
Mk 147 - .02 sec delay | ||
|
ARMED CONDITION |
When base of vane boss is | ||
|
|
1/2" off top of fuze body. | ||
|
FUZES USED WITH |
None | ||
|
ARMING TIME |
10 vane revolutions (approx. 100' air travel). | ||
|
VANE GUARD DIA-METER |
2-3/4" | ||
|
OVERALL LENGTH |
2-1/2" (including vane guar, without booster). |
||
|
GENERAL: |
|
Fires upon water impact for velocities of 300 ft/sec and more. Fires at impact angles as small at 15° to 20°. Probably will not arm if the burning time is shorter than 0.2 sec. or the velocity is less than 300 ft/sec. |
|
OPERATION: |
|
When the rocket is loaded on the launcher, the safety pin securing the setback col-lar is withdrawn. On firing the rocket, the setback collar is forced back by inertia, com-pressing the setback spring and withdrawing the vane locking pin from the hole in the vane boss. The vanes rotates freely, and after 3 to 4 rotations have unthreaded the striker spindle sufficiently that when deceleration occurs the vane locking pin cannot again engage the vane boss. After approximately 10 vane rotations, the striker spindle is unthreaded sufficiently to free the detonator shutter, which is forced across the shutter cavity by its spring. It is stopped by the stop pin and is locked in the armed position by a spring loaded detent housed in the shutter which slips into a recess in the striker guide. When the striker has reached the end of its threads it rotates freely with the vanes as the striker spindle collar rides in a groove in the underside of the fuze body. On impact, the threads on the fuze body are sheared as the striker is forced into the detonator. |
|
Mk 137 Mod 1: The Mk 137 Mod 1 is similar to the 137 but has 10 blades on the arming vanes as compared to 8 and also has a split spacer sleeve. |
|
Mk 137 Mod 2: The Mk 137 Mod 2 is similar to the Mk 154-3. A modified vane lock pin seat prevents premature arming. |
|
Mk 145: The Mk 145 is similar to the Mk 137 but incorporates a .02 sec. delay in the detonator. |
|
Mk 145 Mod 1: A modified vane lock pin seat prevents premature arming. |
|
|
 |
