OK, I was referring to this summary:wmh829386 wrote: ↑Sun Jan 16, 2022 11:49 pmMight be a miscommunication there, I am referring to this.dunmunro wrote: ↑Sun Jan 16, 2022 9:54 pm
The RN called it 'innocuous' shell for a reason. It was designed to minimize kill potential and maximize visibility and the charge was only large enough for that purpose.
Drones were not coming back riddled and the 5% figure included drones where the potential pilot was judged to have been incapacitated.
It is quite possible that some WW2 shells have too much burster in it for splashing modern aircraft. Well, just speculation, and with VT fuze 5" seems to do fine anyway.The rub was that individual shells were not lethal enough. Again and again, drones came back to
base with numerous holes in them. That should not have been too surprising. Tests of 5in shell
fragmentation against an obsolete aircraft (an F7B) showed that the fragments were generally about
the size of a 0.50-calibre bullet. Earlier analysis of the 0.50 vs the 1.1in gun (see above) showed that
a 0.50 would be lethal only if it hit a vital spot. The larger impact-fused shell of the 1.1in was
considerably more lethal. The fleet was unhappy; it wanted larger fragments. BuOrd replied that the
larger the fragments, the smaller the volume they would cover, because there would be fewer of them,
and also because they would be given lower velocities...
Regarding fragment size: The Deadly Fuze has data on that and larger bursters increased lethality even with smaller but more numerous fragments. (these were using mockup IJNAF 'Kate' targets) The large VT fuze also reduced the efficacy of RN 4.5in and 5.25in ammo due to a reduction in burster size. In a separate book, it was stated that the reduction in efficacy was smaller than feared because the resulting fragments were larger and more lethal per fragment.A study of the results of antiaircraft firings by the ships of the Fleet,
from July 1, 1938 to June 30, 1940, gave little cause for cheer or hope for
solution in this area. This study showed that in 307 firing runs by 1.1",
3", and 5" antiaircraft guns against high-altitude, horizontal-bombing
drone aircraft, dive-bombing drone aircraft, and low-altitude, horizontal-
bombing drone aircraft, only 5% of the drone target aircraft had been
hit seriously enough to stop the bombing attack and only 17% hit at all.""
The Deadly Fuze also discusses the use of small black powder charges in VT ammo by the US Army, who were anxious to preserve target drones, after they witnessed the USN destroying a number of drones in the initial ship 5in VT vs drone trials. On the first trial a small Army drone was destroyed at 10k yds! Fortunately this was not repeated against additional drones, even though TTBs were generated and the initial drone hit was described as a fluke direct hit!