Here’s an example. Eight billion others, including missiles, rockets, projectiles, and, by implication, the Batmobile when it’s in a hurry.
Um, it doesn’t.
Did you ever see flame out of an airliner??
Fire out of a jet fighter is from after-burner, which is very efficient. I don’t think it’s on any modern fighter.
Missles, rockets, etc are just that; rockets. They do not have a jet engine (notice no air intake).
And the batmobile… that’s JUST special effects.
I think you meant “Fire out of a jet fighter is from after-burner, which is very inefficient”. That is true. Afterburners add power but they are a very inefficient way to produce additional power. They basically turn a jet engine into a rocket temporarily by injecting huge amounts of fuel into a simple combustion chamber and letting it rip. That can produce flames out of the back under some conditions whereas a jet engine using its turbine to produce power will not unless something is very wrong.
Darn it, that page has a link labelled “boobs”.
Now I won’t be able to concentrate.
what has already been said. that jet is taking off from an aircraft carrier, which means it’s using reheat (after-burner.) Which- as has also already been said- is little more than dumping raw jet fuel into the nozzle after the turbine(s,) and since the exhaust stream is still rather oxygen-rich, that act turns the jet engine into a rocket motor. Based on the photo you posted, I’d wager the pilot had just enabled reheat and the “Fireball” was the initial dump of jet fuel not igniting until after it had left the nozzle.
Just to nitpick a little, an afterburner is a form of ramjet, not a rocket, or at least no more of a rocket than any jet engine is. The line between rockets and jets is blurry when you get to the concept of a ramrocket which consumes atmospheric oxygen, but in the case of an afterburner it’s an inefficent ramjet used for it’s simplicity.
That’s one possibility, although I would have expected him to have the afterburners already engaged and operating in a stable manner before commencing his takeoff roll.
One other possibility is compressor stall/surge. This happens when the airflow into a turbine engine is disrupted to the point where the blades of the compressor section (each of which is a tiny airfoil) experience aerodynamic stall and stop cramming air into the engine. When that happens, the compressed air already in the engine is ejected from both ends: the front barfs up clean air, and the back of the engine farts out a brief fireball.
In the best of circumstances, the stall is a transient event and the engine immediately resumes normal operation, as in the case of this commercial airliner with a compressor section damaged by a birdstrike: watch/listen for the repeated pops and bursts of flame starting at 0:09 and ending at 0:30 (I assume the captain shuts down the damaged engine at that point). In worse cases, compressor stall results in total flameout/shutdown. This article discusses an aborted takeoff by a Russian fighter jet due to stall/flameout, but more importantly it has a photo of an F-18 taking off from a carrier, and it looks very similar to the OP’s photo. The article claims that compressor surge is common on US aircraft carriers; I’ll wager that’s what the OP’s photo shows.
Are you thinking of shock diamonds? Those are the awesome visual effects of supersonic exhaust flow bouncing off the boundary vs. the subsonic atmosphere.
An afterburner isn’t a ramjet at all; ramjets are very simple jet engines whose defining characteristic is that the shape of the intake performs the compression stage without any moving parts- in essence, ramjets are cleverly shaped tubes with fuel injectors at some point.
Typically they’re used on things like missiles that have a high and steady speed- they must have a certain minimum speed in order to get that ram compression going, and they can’t drop below that or they flame out, so they’re good for missiles, and not so much for piloted planes.
Afterburners are just taking advantage of the fact that most military jets use low bypass turbofans and/or don’t burn at the stoichometric ratio for jet fuel- i.e. there’s leftover oxygen in the exhaust. Take that bypass air and hot exhaust moving fast under some pressure in a confined space and put more fuel in, and you basically increase the gas volume and temp (and speed) out the back of the engine, thereby increasing thrust. However, like others have said, this is pretty inefficient.
Look at the picture the OP linked to: there is a large, disorganized, turbulent ball of flame emanating from the exhaust nozzle. It ain’t shock diamonds.
Yes, it is mostly just an augmenter, using fuel to increase the mass and temp of the exhaust. It’s closer to a ramjet than a rocket is, but if there’s no increase in pressure in the bypass output or jet exhaust in the afterburner to enhance the combustion then I guess it’s not much of a ramjet at all.