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7th @BoeingDefense P-8I for the Indian Navy at Seattle ahead of delivery this year- Video

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I saw this towards the back of the engine. Is this what reduces the emission and the fuel consumption???

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I saw this towards the back of the engine. Is this what reduces the emission and the fuel consumption???

View attachment 193616

It's a noize reduction feature, a modified exhaust nozzle/cone. You'll find such systems on all modern jet liners. They reduce engine noise by 30%. Nothing too special, unless you live near an airport.

On a commercial 747:

inside-boeing_s-new-747-8-intercontinental3.jpg


@C130 You sir may not be a reliable ally & may even like to play sanction sanction a lot but no one can beet you in Time management :usflag:

Tell that to Lockheed!!! F-35's been delayed too much! Some programs are early, like the Virginia class... Many more are behind schedule and over-budget.
 
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@C130 You sir may not be a reliable ally & may even like to play sanction sanction a lot but no one can beet you in Time management :usflag:

They use the same production line as the commercial jet manufacturing and Boeings gets paid only when the aircraft gets delivered.
 
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Its called chevron.

A noice reduction technique.

CFM56, the engine of the p-8 chose to built chevron into the core exhaust nozzle. The chevrons reduced jet noise by 1.3 perceived loudness decibels during takeoff conditions.

Thats why the odd shape.


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Chevrons are actually the sawtooth patten on the trailing edge of an engine's pod, sometimes on the exhaust cone too. They too are a noise reduction feature. Different than the exhaust cone though.

GEnx-1B_on_Air_India_B787_(2).jpg


Chevron (aeronautics) - Wikipedia, the free encyclopedia
 
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Chevrons are actually the sawtooth patten on the trailing edge of an engine's pod, sometimes on the exhaust cone too. They too are a noise reduction feature. Different than the exhaust cone though.

View attachment 193661

Chevron (aeronautics) - Wikipedia, the free encyclopedia


But we dont see any sawtooth pattern in CFM56 engine. The technology of this engine developed included three-dimensional aerodynamic outlet guide vanes; a core chevron nozzle; and improved reverser and inlet linings on the nacelle as per their official site.


CFM56-5 Technology Keeps It The Engine Of Choice For Airbus A320s | Press Release | GE Aviation
 
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But we dont see any sawtooth pattern in CFM56 engine. The technology of this engine developed included three-dimensional aerodynamic outlet guide vanes; a core chevron nozzle; and improved reverser and inlet linings on the nacelle as per their official site.


CFM56-5 Technology Keeps It The Engine Of Choice For Airbus A320s | Press Release | GE Aviation

Sorry if I make this a bit confusing, you are right that the P-8 doesn't have chevrons, but there are conditions attached to that.

In this instance the nozzle design is the pylon core nozzle configuration for noise reduction and increased fuel efficiency, but without the chevrons that are seen on civilian airliners who are concerned about noise and passenger comfort. Trust me, the military isn't too concerned about passenger comfort!!! We don't see chevrons on the P-8's CFM56-7b. Equally important though is the pod configuration. Chevrons aren't just applied to the pylon, they are applied to the engine pod too, and on the P-8 we don't see either. The military isn't too concerned about noise issues with its P-8s.

Chevron.gif


Notice the chevrons around the pylon. We don't see such Chevrons on the P-8's engines (the CFM56-7b), though other CFM56 engines will have them, as seen here with a CFM56-5 series on an Airbus A320 jetliner:

F-GTAR_Air_France_(3698209485).jpg


This time we have a chevron pattern on the pylon, but not the pod. Also, the opened sides are the reverser.

It's confusing, but on the P-8 we don't have a chevron configuration as you stated. There's more than one version of the CFM56, this particular version isn't called a Pylon-Chevron core.

The link you provided is for the CFM56-5, but the P-8 uses this:

CFM International CFM56 - Wikipedia, the free encyclopedia - it jumps to the CFM56-7

Same engine, different configuration. Chevrons are the saw-tooth edges, whether an engine will have them or not depends on the engines configuration and the operations demands/concern.

@SvenSvensonov Sir, what's your take on the Pentagon report in which they alleged that the U.S. Navy’s next generation submarine hunter (P-8 Poseidon) isn’t any good yet at hunting enemy submarines?

Bloomberg Business

It's an old report that was based on the P-8s software immaturity, a report that was made in the early days of the P-8 and while it was still in testing. The software bugs are being worked out.

Reports like this:

Report: Navy's New Submarine Hunter Doesn't Work | Defense Tech

Are over a year old now. The system works, if it didn't we wouldn't have inducted it or have plans to purchase over 100 of them.

the P-8 works and has operational experience in a spat with China - the one where the Chinese pilot barrel-rolled over the P-8, as part of the MH370 search, as seen here:

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Exclusive: P-8 Poseidon Flies With Shadowy Radar System Attached

Long story short... it works!!!
 
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