Burner color

[serverandenforcer]

Was wondering lately what the difference is in the different burner color on afteburners. Is it the type of fuel that's being burned or is it a dye that's in the fuel? When I was at the Miramar airshow, I saw the F-16's burners an orange color, but when I was working at my base, and our alert fighter launched (F-16s), the afterburners burned a blueish/purple color. I've also noticed Hornets launching off with a pinkish burner color, but also sometimes with the orange and bluish burner color as on the F-16. I'm just trying to figure what determines the differnce, what afterburner color would be seen most often on fighters, and what are the circumstances that would have a fighter operate with a different burner color. I couldn't find any info on the web regarding this, or atleast nothing that really answered my questions in a clear way.

Edited February 15, 2009 by serverandenforcer

[+Spillone104]

For most of the case depend on the light conditions or the angle you watch the AB exhaust.

For example I've noticed that the flame of the J85 of the F-5E look blue if watched from rear sector but on side sector appear to be red to violet.

Sometimes the color is due to temperature and degree of oxidation of the flame. Hotter=Blue to white spectrum, if on "lower" temperature it appear in the warm red to yellow.

Edited February 15, 2009 by Spillone104

[+wilco]

I'd say it has something to do with oxygen supply, but I'm not sure whether the elevation or the amount of fuel and oxygen in the mixture is that much of a decisive factor. Another point I could think of would be background lighting, because in in broad daylight and against the blue sky it my be difficult to tell if there's more blue or red in a flame.

 

Edit: Too slow...

Edited February 15, 2009 by wilco

[+JediMaster]

I would think different fuel would burn differently. I can't even remember, is anything other than JP-8 in use anymore?

[+ST0RM]

The Navy uses JP-5 on the carrier, but I dont know if they use it on the land bases also. JP-5 has a higher flash point than our JP-8, making it safer for CV use.

 

Another reason for different colors in the burner flame is the age and type of the engine itself. A P&W engine will look different than a GE. Even amongst the same manufacturer, the individual models will differ.

 

-S