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TAIL FIN MARKINGS - Russian Bombs
- Thread starter lulus
- Start date
These are not heights an speed but characteristic time of drop of the bomb.
For instance in horizontal flight we have:
FAB-1000 20,67 seconds
FAB-500 21,42 seconds
FAB-250 21,12 seconds
FAB-100 21,51 seconds
Characteristic time Q (or φ) is the time when a bomb dropped from an airplane in a horizontal flight dropped at a speed of 144 km / h (40 m / s) from an altitude of 2000 m above sea level in standard atmosphere conditions.
In modern bombs, the value of the characteristic time lies in the range from 20.25 to 33.75, this value is taken into account in determining the angle of aiming.
The characteristic time for bombs with a ballistic coefficient of less than 1 can be calculated with sufficient accuracy by the formula:
T = 20.193 + 0.809c
where c is the ballistic coefficient of the bomb.
Knowing (φ), you can calculate the angle of the bomb drop and the distance that it will fly horizontally from the point of drop to the point of contact with the ground
7, 12 and 22 are the speed of wind in m/s at the height of bombing (classical typical values found in the Soviet ballistics books and ballistic tables).
For more details on these coefficients see for instance Бомбометание (1960) By В.И. Кириллов
Concerning the 477, I think that this designates the maximal speed of release of the bomb but I must check that.
For instance in horizontal flight we have:
FAB-1000 20,67 seconds
FAB-500 21,42 seconds
FAB-250 21,12 seconds
FAB-100 21,51 seconds
Characteristic time Q (or φ) is the time when a bomb dropped from an airplane in a horizontal flight dropped at a speed of 144 km / h (40 m / s) from an altitude of 2000 m above sea level in standard atmosphere conditions.
In modern bombs, the value of the characteristic time lies in the range from 20.25 to 33.75, this value is taken into account in determining the angle of aiming.
The characteristic time for bombs with a ballistic coefficient of less than 1 can be calculated with sufficient accuracy by the formula:
T = 20.193 + 0.809c
where c is the ballistic coefficient of the bomb.
Knowing (φ), you can calculate the angle of the bomb drop and the distance that it will fly horizontally from the point of drop to the point of contact with the ground
7, 12 and 22 are the speed of wind in m/s at the height of bombing (classical typical values found in the Soviet ballistics books and ballistic tables).
For more details on these coefficients see for instance Бомбометание (1960) By В.И. Кириллов
Concerning the 477, I think that this designates the maximal speed of release of the bomb but I must check that.
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