Naval History Forums

Could you give a reference for that opinion you have read? I have never come across anything suggesting that bigger plugs were in general thrown out of thick KC plates by large calibre shells than was the case for smaller shells against thinner armor. IIRC in US tests of 14 in APC against ultrathick...

Normal Attack and Scaling At normal attack it is axial forces causing compressive failure that endanger the shell including shock-induced shatter and inertia-induced shatter sometimes called secondary shatter as it occurs later than shock-induced shatter provided that it has not happened. With shoc...

Angle Attack: Breakage Mechanisms and Scaling On p. 93 of the USNMTE Gercke wrote: 'Because of the stresses caused by the transverse forces the projectile must be given a hardness gradient from the nose to the base in order to withstand them. In order to limit the value of M1 [the moment of force c...

Summary Scaling is the feature of armor penetration curves which show a reduced critical velocity with increase in calibre for given T/D (plate thickness/shell calibre) ratio. Scaling is a feature of the penetration curves given in Gkdos100. Nathan Okun attributed this scaling to a reduced ability ...

It is perhaps useful to study, as in Figs 12 and 13 of the paper by Hoyer (which appears elsewhere on this site), the curves showing the critical velocities needed for penetration and that of the projectile terminal velocity with range and inclination. If the critical velocity is below the terminal...

It is perhaps useful to study, as in Figs 12 and 13 of the paper by Hoyer (which appears elsewhere on this site), the curves showing the critical velocities needed for penetration and that of the projectile terminal velocity with range and inclination. If the critical velocity is below the terminal ...

95mm is more incline to bend instead of spalling I think. to be precise MAD over magazines 100 mm (scarps 120 mm) Wh (Zeichnung Panzerabwicklung „Schlachtschiff F“ gültig für Panzerdicken, im Laufe des Baues geändert, Geheime Kommandosache) German homogenous armor plates possibly from from Tirpitz ...

The mention of the paper by Hoyer has drawn my attention to something I had overlooked before. Namely, I had thought that the curves Vg in Figs 12 and 13 were curves of terminal velocity (from its shape) rather than of the velocity at which the shell fractures on impact. Also generally in GKdos 100 ...

The question about AON battleships in the RN. I think no one would dispute that Nelson and Rodney were armored on the AON principle. However, in the KGVs there was at least as much armor before and aft of the citadel as in traditional British designs. The KGVs also raised the armor deck by one deck ...

The point about the 220 mm thick barbette armor on Bismarck. This is indeed low for the period in question, although well up on WW1 ships. This armor was KC. No shell could strike it without having first gone through the upper belt or the upper deck. In both cases the shell would be decapped. On hit...

One point about the overall protection scheme used by the Germans is that it reduced the chances of hits penetrating the citadel by effectively reducing the target area. By such means the chances of damaging hits at ranges where the ship's main armor could be penetrated could be reduced. While a shi...

Paul, I do not know if target motion at the time of impact was a significant factor in armor penetration, but this question seems to have escaped detailed analysis up to now. Often, tthe advantage of light was decisive, such as at Colonel. This advantage involved chance, that of the relative locatio...

I think you are correct in saying that chance could play a big role in naval engagements. The form of the hull, pitch, roll and yaw all affect the overall angle of incidence. The striking velocity will depend on the nominal muzzle velocity, state of wear of the barrel, charge temperature, relative v...

Recently I read the excellent piece about shell damage on Nathan Okun's website, which I recommend. Since then I have come across two accounts of damage to US AP shells that hit Jean Bart that are somewhat at variance with Mr Okun's conclusions. Mr Okun says that because of their sheath hardening US...

On p. 61 of The Littorio Class by Bagnasco and de Toro there appears: 'Each zone [of seven] was connected directly by telephone to the two damage control (or floatation centres): the main centre at frame 144 ... and the secondary centre located near the after propulsion spaces. The damage control ce...