Video: Inside the Tanks - Jagdpanther
Дата: 02.08.2014 21:40:48
Salsify, on 02 August 2014 - 02:13 PM, said: Not a criticism of the video or presenter, I enjoy watching these
but at around 4:25 there is mention of sloped armour
increasing the effective thickness for "no extra weight" which is
something I've often seen mentioned elsewhere but I wonder whether
it's actually true. Maybe I'm just being
pedantic or missing something but at an angle of 35 degrees the
front plate would have to be made almost twice the height to cover
the same vertical height? (It's like if you have a step
which is 1 foot high then a ramp at 35 degrees would have to be
almost 2 feet long)
Hunter1911: Consider two armour plates: one is vertical, and one has an
inclination of 30 degrees from vertical. The armour plates must
both offer a protection equivilant to 100 mm thickness. Obviously,
the vertical plate must be 100 mm thick. If using pure trigonometry
to calculate the required thickness of the other plate, we would
get 100 mm × cos (30) ≈ 87 mm. While this result would seem to
indicate a weight saving of 13 percent, it does not take into
account that the armour plate would have to be longer to cover the
same area.
If the armour plate would have to be 1000 mm tall, the height of the vertical armour plate would naturally be 1000 mm. The length of the sloped armour plate, however, would have to be longer, since sloping the armour would reduce the height covered by a plate 1000 mm long. The exact length is easily calculated as 1000 mm ÷ cos(30) ≈ 1155 mm. Since 100 mm × 1000 mm ≈ 87 mm × 1155 mm, it is demonstrated that the weight will be identical of two plates that has the same horizontal thickness and covers the same area, regardless of slope So technically you are not wrong. But as the Jagdpanther is a tank destroyer, rather than a gun tank, its frontal sloped armour extends from edge of lower glacis panel to the top of the superstructure, thus giving it necessary additional length, and not gaining extra weight compared to what would happen with a gun tank.
If the armour plate would have to be 1000 mm tall, the height of the vertical armour plate would naturally be 1000 mm. The length of the sloped armour plate, however, would have to be longer, since sloping the armour would reduce the height covered by a plate 1000 mm long. The exact length is easily calculated as 1000 mm ÷ cos(30) ≈ 1155 mm. Since 100 mm × 1000 mm ≈ 87 mm × 1155 mm, it is demonstrated that the weight will be identical of two plates that has the same horizontal thickness and covers the same area, regardless of slope So technically you are not wrong. But as the Jagdpanther is a tank destroyer, rather than a gun tank, its frontal sloped armour extends from edge of lower glacis panel to the top of the superstructure, thus giving it necessary additional length, and not gaining extra weight compared to what would happen with a gun tank.
Video: Inside the Tanks - Jagdpanther