Why do the engines of airplanes sound like they are rattleing when they just landed and the fan still kind of spining.???
2007-10-10 17:16:51 · 9 answers · asked by Tazmanian Devil 4 in Cars & Transportation ➔ Aircraft
Do you mean when they are just turning over, like in a breeze?
The fan blades aren't secured snugly, so as the fan turns the blades shift slightly in their mounts. I like the sound, almost like a wind chime sometimes.
Anyway, the design of the root of the blade and the hub of the fan is such that the very small amount of movement isn't enough to allow the blades to go anywhere, they are just shifting the tiniest amount. When the engine is under power the blades load up and are jammed solidly in their mounts by both the thrust they are generating and the centripetal forces due to spinning. So it is not an issue for an operating engine.
Why are they slightly loose? If the blades were an interference fit they would be very hard to change and would apply huge forces to the hub due to differential expansion because they are made of different materials.
2007-10-11 02:52:30 · answer #1 · answered by Chris H 6 · 2⤊ 3⤋
The engine is a turbofan, The front blade assembly is the fan section. The blades fit loosely inside the fan assembly. The tolerance is there to allow for expansion and contraction of the metal that occurs during normal operation of the engine to prevent metal fatigue of the fan components. The clicking sound is the blade sliding back and forth as the fan windmills in the breeze and the blade transitions from the top to the bottom.
Cool huh?
2007-10-14 13:31:46 · answer #2 · answered by Older1 4 · 0⤊ 0⤋
737's are among the most popular commercial aircraft available and one of the safest. The world wide fleet of 737's flies millions of hours a year and there are only a few problems. This 737-200 is most likely an aircraft sold to a Mexican airline when the airlines began struggling financially. Don't be worried about the age too much either, the USAF is flying Boeing B-52's that are nearing 50 years old.
2016-05-21 03:10:14 · answer #3 · answered by ? 3 · 0⤊ 0⤋
Virtually all modern jet engines make a rattling sound when they "windmill" or rotate from the wind. The turbine blades are designed to have some movement because of the high speeds they rotate at when in operation. When the engine is at rest, they unseat slightly causing the sound you hear. (I have tried to put this in simple terms so that is clear to someone who doesn't have a background in aviation can understand it)
2007-10-11 05:58:02 · answer #4 · answered by Otto 7 · 1⤊ 0⤋
Patric got it. When the engine is windmilling the tolerances between the blades is very sloppy . What you hear is the blades rattling against each other. When the disk is turning and the blade is coming up ,the blade is hanging down and when the blade get`s to the 12 o'clock position and then goes to th 1 o'clock position it flops over and hits the other blade
2007-10-11 06:22:13 · answer #5 · answered by miiiikeee 5 · 0⤊ 2⤋
Because they are turbine engines. When the fans are turning at a high rate of speed they have pressure on them. When the pressure is taken off during landing, they settle back into place. Thus, making the rattling noise.
2007-10-10 17:22:19 · answer #6 · answered by Anonymous · 0⤊ 5⤋
they have reverse thrusters on their engines. There is a thing that actually closes on the back of the engine and deflects the thrust the other way. So what was pushing the plane through the air is now helping it stop. You are probably hearing the reverser buckets engaging, or the bypass ducts opening (both do the same thing, but just through a different way)
2007-10-10 18:48:20 · answer #7 · answered by Matt H 2 · 0⤊ 7⤋
That's because of the turbine brake that is used to slow down the plane when they make contact with the runway.
2007-10-10 17:20:54 · answer #8 · answered by redd headd 7 · 0⤊ 7⤋
Now you tell me! I'm cutting my airline ticket up!!!!
2007-10-10 17:29:09 · answer #9 · answered by wheeliebin 6 · 1⤊ 4⤋