Why are fighter planes still falling down because of birds getting into the engine? Can't they make some kind of protection, like a grid?
Answer from: Yuri Bushuev:
Editor-in-chief of the online publication GAZETA GARDENER...
In aviation, a bird is just one of the types of foreign objects that get into the engine's gas-air path, which are dangerous in all modes from takeoff to landing. On takeoff and landing, besides birds, various objects from runways, snow and ice, stones, mud on unpaved airfields can also come across.
Such measures are not applicable to fighters because of the necessity to provide high aircraft performance characteristics, and there is no question of birds' safe penetration.
Some fighters, e.g. MiG-29, have a special protection of engine air intakes from foreign objects hitting the runway, when the air is taken from the upper part of the wing. To make the engines more reliable and to prevent birds from getting into the engine fatal, the compressor's first stage working blades are made of steel instead of brittle titanium alloys.
Such measures are not taken on passenger aircraft for economic reasons. A great danger with low-lying engines are foreign objects from the runway, the cleanliness of which is paid the utmost attention in airports.
Besides that most of both fighters and passenger airplanes have two or more engines and if a single bird hit which caused failure of one of the engines, the plane can land safely at the nearest airfield and sometimes completes its flight on the intended route. Collisions with a flock of birds are quite rare.