Why are there spirals on engines to begin with? Why does Rolls Royce and IAE have the yellow spiral instead of white and i noticed some 737-300/400/500's without the spiral. Does this mean the engines are older???
Actually,they are used to prevent birdstrikes in the engine.In an engine without the spirals,the birds treat it as a dark cave and fly in, only to get killed by the fan blade and the engine loses power.
Engines with the spiral are less prone to birdstrikes as the birds see the stripes and dare not go in as it is bright to them.
All this talk about birds and engines, I have a question. Don't birds actually HEAR the roar of engines? I mean, they ARE quite loud. Or is it that the engines are so powerful, that by the time they hear them, it's too late and they're already being sucked into them? I guess this is also possible since engines are also quite powerful.
Now, I had heard the "bird theory" many times, and I just can't really believe it.
I mean, planes fly an awful lot faster than birds do, even at their slowest. A bird simply won't see the white stripes on the engines. What they will see is a REALLY BIG FRIGGIN' BIRD that it would be wise not to mess with.