Dirty Exhaust question

[Atreides 144]

Hey,

Just a question with regards to the dirty exhaust, I'm a stickler for details and just wanted to get this out of the way. With regards to the exhaust which gen of aircraft's Russian, American and European had "dirty exhausts" ? Modern, 90's+ gen notwithstanding ? Were Brit aircraft's like the Hunter and Vixen less likely to spew black smoke as oppossed to the Mig's and Cold War gen American a/c ? I'm guessing that excluding the MIG-29 any aircraft's of Russian origin was prone to black exhaust, along with a fairly decent number of cold war American aircraft's or is it that these aircraft's would only spew black smoke at certain throttle setting's ? (Lower throttle more smoke, higher less to none ?) Just wanted to know for realism's sake and just to expand my general knowledge about mil a/c's

 

Thanks in advance to anyone who answer's such a mundane question

[+SkippyBing 8]

According to my dad (who may be slightly biased) the Vixen had a pretty clean exhaust, he thinks because it was a turbojet rather than a turbofan but he's not 100% sure. I'd assume then that anything else that used an Avon would have a cleanish exhaust too. Certainly most of the photos I've seen of Vixens and Hunters didn't have much in the way of exhaust smoke.

[Atreides 144]

^ Thanks. Now that I know about the "BRIT" aircraft's that just leave's the USSR, US and french...though I think the French had clean exhaust's as well...

[JediMaster 451]

Pretty much all those older engines smoked at some point. The problem with many planes is they could be retrofitted with kits to make them smoke less at a later date. The F-4E for example was very smoky when it entered service but far less so by retirement in the USAF.

The MiG-29A was notorious for being almost as smoky as the F-4E.

 

It's the hallmark of a turbojet, as well, and the introduction of turbofans reduced smoke to a trickle if at all, although that's not 100%. However, pretty much every engine used before 1970 was a turbojet and they all smoked. Most planes introduced since 1970 use turbofans and smoke little.

[+SkippyBing 8]

Jedi, that makes sense to me. I'm wondering what effect the grade of fuel has on the smoke, for instance when embarked naval aircraft tend to use a higher flash point fuel (to reduce the fire risk on the ship) I don't know whether this would make this better or worse with regards to smoke. I do have some DVDs of Vixens, Scimiters and Buccaneers operating off carriers and there doesn't appear to be much smoke but that may be due to the age of the video etc.

[+Typhoid 231]

Jedi, that makes sense to me. I'm wondering what effect the grade of fuel has on the smoke, for instance when embarked naval aircraft tend to use a higher flash point fuel (to reduce the fire risk on the ship) I don't know whether this would make this better or worse with regards to smoke. I do have some DVDs of Vixens, Scimiters and Buccaneers operating off carriers and there doesn't appear to be much smoke but that may be due to the age of the video etc.

 

you are refering to the use of JP-5 aboard ship and JP-4 ashore by the pale blue suit boys (USAF). (Using the JP-4 cost me an aircraft and the contractor 5 dead one time)

 

no, the fuel did not make any appreciable difference. The engines were the key. Newer technology engines smoke less. The F-4S we flew from Midway in the early 80's were largely smokeless as compared to the F-4J that preceeded it.

 

When controlling sometimes the first call I'd get back from a fighter on his target would be a smoke call at about 10 miles.

[+SkippyBing 8]

Yeah, we use F-44 afloat and F-30 ashore (I think, there's a number of options!) I'd have to check the cross-reference but they probably equate to JP-5 and JP-4. We don't have any problem mixing them but again that's probably down to engine design, I think the Wasp would take just about anything that burns! Being rotary all the smoke gets dissipated by the big fan anyway!

[Atreides 144]

As always "THANK YOU VERY MUCH". It's the people on this site that keep sharing their knowledge in different areas amongst a great many other things that make's this site great. Thanks again.