Jet exhaust

If you get FSM (the mag.) the Viet Nam issue had a F-100 conversion in it. That guy did a really good job simulating the area that got hot and lost paint. It may help you a little, I think he tells how he got the burnt metal look. Hope this helps a little...

Unfortunatly, it may be a bad thing on here, but I don't get the mag. I'll have to look into that though.

However, the situation I'm talking about would be an aircraft with unpainted exhuast areas. Say for example an f-15.

Dana

Most modern jet exhausts really don't need a lot of weathering on the outside. With the newer more effiecient engines they really don't smoke too much and don't produce a lot of soot, like say an F-4. I use Testors metalizer or Alclad for my exhausts, usually "burnt metal". After I have the main color I do whatever weathering is needed. If you look at the F-15 photo below you can see that the exhaust area really is pretty clean, maybe just a wash over the colors to add depth would be enough. Something else to consider is the inside of the exhaust. Most newer jets exhaust pipes have an off white look to them on the inside. I will try to see if I have a picture of that somewhere.

An F-4 would be a closer match to a Mig-19. Both aircraft have two engines and some portion of the fuselage extends past the nozzles. That area would have to be made of a different metal and would need alot of "effects" to look right. Also, both aircraft are of older design and probably would have alot of soot etc.

Sorry if I didn't specify.

Funny that, I was looking around a Saudi F-15 this very morning, especially the exhaust!
yes, it is an off white colour inside, and yes, I would agree that the inside of an older aircraft would be 'sootier' than a modern one, I doubt early Soviet jetfuel would be as refined or as well burnt as modern stuff. As for the outside, I tend to pick out the different area's of an exhaust in slightly different shades, the petals, for instance, are lighter than the inner protions. for the hotter bits, try adding a hint of copper to your titanium or whatever, it makes a noticeable difference.
Pete

Actually, Soviet aircraft didn't create a lot of soot from there engines. They're jet fuel is not kerosene based like ours, but was alcohol based. I don't know if this is still true, but thats what we were told in the Air Force in the early 80's. That is why their jets didn't leave a smoke trail like ours did.

Would any of you guys have any references to this happening on aircraft with natural metal finishes? How would this look on an F-86, for instance, and what would be the easiest way to duplicate it?

I don't think the F-86 had a problem with jet exhaust staining since it's tailpipe stuck out at the very back of the jet. Not much of the tailpipe was visible but it would be a burnt metal color on the outside and a sooty black on the inside.

The reason that the inside of the exhaust end of modern jets seems to be white or beige is the fact that each exhaust 'petal' is lined with a ceramic compound.

The best jobs I've seen done on this was when the inside of the 'burner can' was airbrushed a off white color and then dry brushed with black and brown streaks to provide the 'burned' effect.

To the point of the original question, NO the hot sections of most jets are not made from titanium. Titanium’s expansion characteristics don’t make for a good fit for use in jet engines. Most of the hottest areas in turbojet engines tend to be made from nickel alloys. Russian jets are famous for liberal use of steel where ever strength is needed. (i.e. structure members and aircraft skin) Not a lot of aluminum alloys were available in the old USSR. Lacking specialty machining tools and manufacturing techniques, Soviet designers tended to ‘over build’ their airframes and engine specs. (Remember how shocked everyone was when that Mig-25 flew to Japan and turned out to have a steel skin with vacuum tubes in some of the electronics?)

I’d probably think about using a base of some variation of stainless steel with some aluminum coloring for variation and then highlight with nickel and copper in some of the hottest areas. Adding some darkening to the paint to give some character and depth should give you the look you want.


Best of Luck,


Jamie