Ever wonder why the 787 engine cowlings are not smooth?

That’s a pretty cool article. I’ve never heard of non-mechanical ‘morphing’ technologies on aircraft parts. Looks like this all has to do with temperature. I bet that introduces a variety of complications. The article is dated 2006, so maybe those complications have been uncovered. Thanks for sharing that… good read.

1 Like

777X Won’t have chevrons. Boeing has already done away with Chevrons for 777x after finding out more effective ways of noise reduction :)

1 Like

The chevrons aka ‘cowling teeth’ are used to reduce noise levels…

But some people don’t like waking up at 3:00 AM because of a jet screaming above them

1 Like

Keep in mind that the chevrons actually decrease thrust of the engines because there is less cowling for the air to be pushed through. If they filled in the “teeth” they can get another 1500 lbs of thrust out of the design. The same theory applies to rocket nozzles, engines designed for vacuum operation is more efficient because of the larger engine bell allowing for more exhaust gas expansion before being ejected out the back.

The 777X will not have the chevrons, just a different cowling for noise reduction.

Yeah, but I, and 95% if the globe, likes sleeping more, and airlines like being able to fly their planes wherever. Thats why the Concorde was banned from flying to the us for so long.

1 Like

The passengers prefer them quite, so do airlines and airports.

1 Like

it also makes a lot better the mixture of hot and cold gases exiting the nozzles reducing sound even further , its like a huge hush kit in tubojets only in turbofans

1 Like

Non existent. Back on topic…

1 Like

I personally love hearing the roar of a big jet engine. Don’t think I’d ever get tired of it… ok, unless I was sleeping, maybe. 😎

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.