Why the jet engine does not shut down in the rain?

Question

Why the jet engine does not shut down in the rain?

Answer 1

They used to, but modern engine management systems can deal with water intake.

Answer 2

couldn't agree more wth Vincent G. Also the centrifugal action drives the water outward in the bypass and don't forget pilots part is they switch the ignition "on" whenever passing rain or turbulent areas. In case of modern fly by wire aircraft ignition is switch on automatically by the EIVMU ( engine interface & vibration monitoring unit).

Answer 3

the water droplets (rain) are almost instantly turned to steam when entering the jet engines combustion and fuel injection area.

the steam as it flashes off into  hot gas releases both hydrogen and oxygen which help the fuel to burn more efficiently.

  unless a  major influx of water was ingested such as enough to wash over the turbines in fluid form, then it will hardly have an impression on the engine except to make it run a little  smoother and more powerfully.

if? a water ingestion ( wave?) was to enter and the engine would not be able to  turn this into steam  ,then the hydraulic effect on the turbines blades etc would cause engine failure and  flame  out ( engine shuts down). probably with  engine  turbines breaking up and ruining the unit permanently.

Answer 4

Vincent G is generally correct, but i would add that when the certification tests are performed, they are done at whatever flight condition is shown to be the critical point in terms of water ingestion. Usually, this occurs with the throttle setting at flight idle. Certainly, the water is all turned to steam and, as mentioned elsewhere, gets up to 600 deg F or so if the engine is running at max throttle. But at flight idle, this can be a little more problematic. The best way for engines to avoid flameout at flight idle is to centrifugally drive most of the water into the bypass and away from the core. There is a substantial amount of water that gets ingested, and it is amazing to see these engines swallow all that water and accelerate as if it wasn't there at all. If they can't do that, then they don't get certified - and they don't fly.

Answer 5

They are designed in a way that they cannot be shut down by rain, you will be amazed on what it would take to shut a jet engine down...

Answer 6

Would you believe they are designed in such a way as to avoid being shut down by rain? Water ingestion tests are actually part of the certification process.

It could be noted that, since water is denser than air, most of the droplets would be directed towards the periphery of the engine (i.e. the bypass) instead of inside the high pressure compressor and combustion chamber. Whatever gets in through is turned into steam and only moderately impact combustion. It may be important to note the water does not put out fire because it is water, but because it absorbs heat and that steam displaces air reducing the amount of oxygen available for combustion. This later process cannot take place in a jet engine as the air is inside the combustion chamber already.

Answer 7

It's going to take more than a little rain to shut down a jet turbine. As much fuel as they burn rain is going to be vaporized inside the engine.

Answer 8

By the time the water vapour reaches the back end of the compressor, it's at about 600F.  If you've ever seen engine tests carried out prior to fitment to aircraft, you'll see that they can handle a phenomenal amount of water without flaming out.