VT fuzes

The VT fuzes can be used only in deep-cavity projectiles (booster cavity is 2.75 inches deeper than for PD, MT and TSQ fuze booster cavities) without the supplementary bursting charge... 

It seems that VT fuzes for bombs were invented by the Germans before WWII and some of them are described below under "Bomb Fuzes". British also started to work on VT fuzes before WWII and then, in August 1940 work started in US. By 1943, the US Navy started to use them against Japanese planes, especially the "Kamikadze"(suicide) planes. In 1944 US Army used them successfully at the battle of Ardennes... 

VT fuzes may also function under the influence of nearby bursts or fragments... 

Several modifications of each standard type of VT fuze have been made to incorporate various improvements in the elec-... 

The types of fuzes listed in Ref 20a, pp 258-59 are evidently obsolete. Unfortunately no drawings of mechanisms of recent VT fuzes are given in Ref 52, but just external views... 

When adopted for single suspension (by suspension lug welded to the body), only instantaneous or VT fuzes are used, but fitting of a mechanical time fuze is permitted with the addition of an adapter-booster. Its body diam is 6.06-in, length (with fin assembly M101) 28.0-in, total weight 86.6-lb (when loaded with. 11.4-lb of Comp B), or 87.4-lb (when loaded with 12.3-lb of TNT)... 

About 14 types of nose fuzes (of which 4 types are VT fuze) are used in GP bombs, old series, in addn to 8 types in tail fuzes New Series GP Bombs are not listed in Ref 44, but two of such bombs 750-lb Ml 17 and 3000-lb Ml 2 8 are described in Ref 51a, pp 2-26. 2-27. They are designed for high blast effects and for improved aerodynamic performance accuracy in flight when released from most altitudes and airspeeds. Their bodies are cigarshaped with a conical fin-assembly bolted to the rear. This can be seen from Fig 2-5. The Fig 2-20 of Ref 51a showing their cutaway view is not reproduced here because its lines are too faint to understand the inside construction... 

Fig 4-20 BOMB NOSE PROXIMITY (VT) FUZES (Ring Type and Bar Type)... 

There are two types of proximity (VT) fuzes, the bar-type and the ring-type (Fig 4-20. The bar-type fuze can be used effec-... 

While only three models of the bar-type and one of the ring-type have been standardized, addnl experimental models have been issued. A list of current US VT fuzes giving their applications in various bombs is in Table 4-20, p 4-87 of Ref 51a... 

This VT fuze can also be used with any GP, Frag or Chem bomb weighing 100-lb or more which takes nose fuze AN-M103A1 (shown in Fig 4-1) or M163- The nominal MinSAT of this VT fuze is 3600-ft. It is extremely sensitive and its tactical use is independent of height of release, speed of aircraft or type of terrain (Ref 51a, pp 4-88... 

Bomb Adapter-Booster, M126A1 (T45E1), shown in Fig 5-4, permits the use of a 2-inch thread for MT or VT fuzes in the new-series and the low-drag GP bombs, including Snakeye I. Its overall length is 6.83-inches, diam ca 2-in and the wt of Tetryl booster... 

G. Wright, "Group I Test on Safety and Arming Mechanisms for T3000 and T3001 VT Fuzes , PAMR 57 (May 1954)... 

Fusie h obus — Shell fuze Fusee percutante — Percussioa (impact) fuze Fusee a proximite radioelectrique — Proximity (or VT) fuze... 

Fig 4-21 on p D997 for Nose VT Fuze, AN-M166 Bomb Hydrostatic Fuzes, such as shown in ... 

Proximity fuzes (VT), which produced spectacular improvements in the effectiveness of anti-aircraft (and other) artillery in WWII, are also radar devices. The VT fuze has a sample amplifier connected with the equally simple oscillating detector and antenna when the output of the amplifier is of sufficient magnitude (ie, when the target comes within the kill-radius of the shell) the firing circuit (usually a fnyratron) triggers the detonation (Ref I) Refs 1) E. Luttwak, A Dictionary of Modern... 

Espoleta de radioproximidad — VT fuze Espoleta de retardo — Delay fuze Espoleta de tiempos — Time fuze, aerial burst type... 

Fig 1-98 on p D919 is for Typical VT Fuze and are listed on p D921 without Figs the following ... 

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