[Andrew]

Originally Posted by lanslide

Are we talking about the engine shrouds vs. the engine nozzles being of different and flip-flopped color? And, while we're at it, what is a "feathered" nozzle? (careful Skunky! - it's a loaded question - careful again! - but really - what is it?

yeah the engine shrouds and the nozzles. Even VF-31's last tomcats seem to have darker shrouds than the nozzles

[David Hingtgen]

Feathered generally only refers to F-15's, they're the only plane I know that has had them removed. The feathers are the plates which make up the oouter part of the nozzle--it's what you see on most planes as the nozzle itself. But many F-15's had them removed as the v.stabs created turbulence which tended to break the feathers off, so on F-15's you can see "into" the nozzle at the underlying structure itself.

Have a look, this one has one feathered, and one featherless nozzle:


The divergent nozzle itself is rather small, the feathers are just an aerodynamic covering over the parts that open and close the nozzle.

Due to sheer numbers/time, most F-15 pictures will show featherless nozzles, especially if it's a USAF F-15C or D. And all E's were always featherless.

[jjgilz]

Wow Dave, you know alot about the details of aircraft. Are you a hobbyist or engineer? What is your normal job?
Jeff

[David Hingtgen]

Nope, not involved with planes in any way other than my hobbies-----I'm just observant. I get asked that question a lot though.