Blue afterburner?
 

One question for all russian hardware specialists. How come russian suhoi fighters have blue flame afterburner compared to all other fighters which have ornge flames shooting out the back.
Is it better burning, higher air/fuel ratios, different introduction fuel to air?

http://www.jetphotos.net/img/1/3/4/3...1186946343.jpg

http://i29.photobucket.com/albums/c2...7/SUN_4978.jpg

And the Brits thought that Natural Gas would be no use for Fast Jet fuel...:)

Yeah, looks like kitchen stove :rolleyes:

Do they have Pimp My Ride in Russia? :8

http://www.metacafe.com/watch/384526...ssian_version/


... just like they do in america... raptor powerplant


http://static.howstuffworks.com/gif/f-22-raptor-12.jpg


Come on guys. Let's get real smart ass stuff in this thread.

Well, I'm no combustion expert, but the general physics of the matter is that the hotter something is, the higher the frequency (bluer) the light is.

pb

Gratuitous reheat photo, apologies for the quality, I don't have the best camera in the world!

http://i51.photobucket.com/albums/f3...a079Medium.jpg

I'm going to look really stupid now....
But isn't the reheat blue while stationary or just starting the take off run because there is a limited amount of cold air being sucked in while on the ground... whereas in the air, cold air is literally forced in rapidly which could in effect cool down the burner slightly to make it an orange colour as you see it when it's airborne and whizzing about the sky.

In flight photo:

http://i29.photobucket.com/albums/c2...7/SUN_4823.jpg

Thank you guys. Blue flame is in deed higher temperature. I'm guessing its better fuel introduction and more air left out from main combustion chamber.

Seeing the picture of the F3 doing a ground run in full reheat, I'm reminded of a story I heard years ago about a Lightning doing a ground run back in the 60's that ended up getting airbourne with one of the ground crew in the hot seat.

Any truth?

Yes.

It was at Lyneham when it had 33MU (who serviced Lightnings) based there.

W/Cdr Walter Holden, whilst carrying out engines runs to trace a fault in XM135, found himself in full reheat running allong a runway at Lynham. Forced to lift it off the ground, without canopy or flying equipment (to avoid a fuel tanker I think), he managed to put it down after four attempts, with only minor damage to the tail.

The 'colour' also depends when the photo is taken. In the image below the top burner has just been lit. Raw fuel v fuel/air?

http://s178.photobucket.com/albums/w..._0666_2030.jpg

Click image for full size.

Not all Sukhoi Flanker variants have blue burners.... this one is airborne with orange burners
http://www.globalsecurity.org/milita...es/su30_01.jpg

Must be because of all the extra stores its carrying

possible (and boring) answer is to cast your minds back to the Bunsen burner flame: blue = hottest due to max amount of air being admitted through the air inlet/collar and complete combustion occurring whereas yellow indicates least efficient/insufficient oxygen to burn the gas

I'm thinking of the same principle. Blue afterburner at it's max efficeincy.

beat me to it:}

My bad - shouldn't have assumed it was an F3 from the picture.

Thanks, Helpful Stacker, for the answer on the Lightning.

I think you'll find it's largely a photographic artifact concerning when and how you shoot them. At night they almost always look blue or blue-pink, but it's not very luminous and generally invisible in daylight. Also they tend to be blue when they're just starting up and the fuel/air mix is very lean. Video cameras tend to see it whiter than stills cameras since they tend to have less IR filtering on the sensors.

Must admit, I'm never quite sure why it's useful to be throwing all that flame out the back, since if it's burning outside the engine it surely can't be all that propulsively useful.

Phil

Geek Answer
 

"it surely can't be all that propulsively useful"

Not useful? Ask any FJ mate how he'd feel about taking off in dry power!

N Joe