Abstract | The testing of Aircraft engines or structures against bird impact is often carried out by placing a real or synthetic bird carcass in a gun, and firing it at the target structure by means of a charge of compressed air.
Since the "bird" is essentially a bag of very viscous fluid (e.g. gelatine or grease), when it is exposed to an acceleration of 100 g, or more, it has a strong tendency to "mushroom" in the barrel.
If the "bird" is large enough to fit the barrel of the gun in use, the design of the "sabot" or case in which the “bird " is contained for firing is very simple (Ref. 1). However, if a smaller bird is being fired from the same gun, as is often the case, the sabot design is more difficult. Such a sabot has to preserve the "bird" from mushrooming, to stabilize it in the barrel, and has to be discarded from the bird at the gun muzzle so that it does not remain with the ‘bird’ and cause spurious damage to the target which may be as close as six feet to the gun muzzle. |
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