Aces High Bulletin Board
General Forums => Aces High General Discussion => Topic started by: mentalguy on March 05, 2006, 07:31:45 PM
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When did they start using AB on jets?
Thanks
MG
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the first fuel leak ;)
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Operationally, I believe after the Korean War. F-100 Super Sabre?
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Originally posted by zorstorer
the first fuel leak ;)
LOL POP..........WOOSH
MG
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and the first USA afterburner was developed at NACA 9before NASA) Langley in October 1943. No, that's not a typo.
However, since the british were well ahead of us in jet propulsion into the 1950s, I would guess that they developed it first. I just can't find any record of their achievment.
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http://www.bbc.co.uk/dna/h2g2/A882272
The contract for the development of an engine for the M.52 went to the Whittle Company, headed by Frank Whittle - the inventor of the jet engine. The resulting engine was given the designation W2/700 and was fitted with an afterburner2.
That was 1943 as well, I imagine it was probably only a few months earlier then the American afterburner.
Actually take that with a grain of salt, they say "Gloucester Meteor" instead of Gloster Meteor.
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the british call it reheat, probably why you cant find anything on afterburners.
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whats so special about an afturburner, its just pouring raw fuel into the turbine right? Seems it would be something that they had to deal with since the start of the jet engine.
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I think the fuel gets poured toward the end of the turbine. Otherwise the turbine will melt or something bad.
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Originally posted by Kermit de frog
I think the fuel gets poured toward the end of the turbine. Otherwise the turbine will melt or something bad.
gets dumped in the Exhaust directly through injectors, to burn up the remaining oxygen, is why you see the controllable nozzles either opening/closing at the tail section of the jet engine.......
4 main parts to a jet engine:
Intake - Compressor - Turbine - Exhaust
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The GE J-79s in the F-4 had a mechanical striker in the exhaust section, just after the turbine, that sparked and lit the raw jp to be able to go into burner. Don't know if all afterburners are lit that way though.
All the best.
Cement
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Post Korean War (1950-53). The F-100 and MiG-17 both used it, but neither saw service in Korea. Hawker Hunter also did.
Mid 1950s for general usage on fighters.
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Originally posted by TequilaChaser
gets dumped in the Exhaust directly through injectors, to burn up the remaining oxygen, is why you see the controllable nozzles either opening/closing at the tail section of the jet engine.......
4 main parts to a jet engine:
Intake - Compressor - Turbine - Exhaust
The nozzles actually help to form something of a ramjet at the back end of the engine, after the turbine section. You've got alot of fast, already energetic gas that's being compressed and combusted again for even more energy, and thus thrust once it squirts out the back end and mixes with all the cold air outside.
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From "How Stuff Works"
A jet engine, like a rocket engine, is a reaction engine. It works by throwing mass in one direction and taking advantage of the reaction in the opposite direction. In the case of a jet engine, the engine burns fuel (like kerosene) with air from the atmosphere. The burning fuel heats and expands the air, and this hot air shoots out of the exhaust-end of the engine to create thrust.
Most modern jet engines use a turbine to improve the efficiency of the engine and allow the engine to work at low speeds. One part of the turbine sucks in air and compresses it before the fuel is injected. The back portion of the turbine acts like a windmill, extracting energy from the exhaust gases and using the energy to spin the compressor portion. See How Jet Engines Work for details.
A modern turbine engine is extremely efficient, and there is still a lot of oxygen available in the exhaust stream. The idea behind an afterburner is to inject fuel directly into the exhaust stream and burn it using this remaining oxygen. This heats and expands the exhaust gases further, and can increase the thrust of a jet engine by 50% or more.
The big advantage of an afterburner is that you can significantly increase the thrust of the engine without adding much weight or complexity to the engine. An afterburner is nothing but a set of fuel injectors, a tube and flame holder that the fuel burns in, and an adjustable nozzle. A jet engine with an afterburner needs an adjustable nozzle so that it can work both with the afterburners on and off.
The disadvantage of an afterburner is that it uses a lot of fuel for the power it generates. Therefore most planes use afterburners sparingly. For example, a military jet would use its afterburners when taking off from the short runway on an aircraft carrier, or during a high-speed maneuver in a dogfight.
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Originally posted by mentalguy
When did they start using AB on jets?
Thanks
MG
I haven't looked at Brit and Soviet designs, but afterburning engines in US jet aircraft were introduced in 1948. Planes such as the XF7U, XF-92 and XF-90 were all fitted with afterburning engines. Production aircraft included the F9F-6 and F-86D, both of which had prototypes flying in 1951.
My regards,
Widewing
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saw on a show the other day the US in the early 40s or late 30s
had a 2 engine jet fighter on drawing board. it had front kenards and
the engines where to have afterburners. design specs said it would be
supersonic capable. they killed the idea, thinking jet power wasnt needed.
will have to find the name for the plane.
whels
P.S.
found it.
http://tanks45.tripod.com/Jets45/Histories/Lockheed-L133/L133.htm
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Originally posted by Tails
The nozzles actually help to form something of a ramjet at the back end of the engine, after the turbine section.
yep, after the exhaust section attached to the end of it
whels:
P.S.
found it.
http://tanks45.tripod.com/Jets45/Hi...d-L133/L133.htm
while checking out ya link, whels, reminded me of the B-17 gunners manual a WWII vet gave me , inside it had 2 B&W pictures of the first P-80's which were painted white ( not the prototypes I do not believe though ) I need to go dig that thing out of storage...
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thinking jet power wasnt needed.
just like how they thought our fighters didnt need guns anymore at one point and all engagements would be BVR.
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Originally posted by zorstorer
the first fuel leak ;)
:lol Good one.
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6 parts to Jet engine
inlet to diffuser - free stream
diffuser exit - compressor entrance - free stream slowed, pressure raised
compressor exit - burner entrance - pressure raised (work done)
burner exit - turbine entrance - fuel burned temperature raised
turbine exit - nozzle entrance - temperature lower (work extracted)
nozzle exit - pressure lower velocity raised thrust produced
temperature, presssure, velocity, mass are distinct at each location.
-MrD
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Originally posted by MrDick
6 parts to Jet engine
no offense, MrDick, I guess the US Navy mistaught me when I went thru AD A-School ( Jet Mech ) at NAS Memphis ( Millington ) back in the early/mid 80's.......
TC
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C' mon TC....everyone knows that squids don't know nuthin when it comes to flyen
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6 stages
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Originally posted by TequilaChaser
no offense, MrDick, I guess the US Navy mistaught me when I went thru AD A-School ( Jet Mech ) at NAS Memphis ( Millington ) back in the early/mid 80's.......
TC
I graduated that school in December 1975. It was called ADJ school as there still was an ADR (recips) school back then. Were they still using those tired old A-4Cs for turn-up training?
I liked the area, even if it was a bit redneck. Had a some good times in Memphis, at Overton Square.
My regards,
Widewing
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Originally posted by Widewing
Were they still using those tired old A-4Cs for turn-up training?
I liked the area, even if it was a bit redneck. Had a some good times in Memphis, at Overton Square.
My regards,
Widewing
had both A-4's and F-4's to do turnquals/turn-ups......
I spent alot of time at silky Sullivan's bar, bought alot of DiverDown ( 1 gallon paint bucket ) mixed drinks :-)
could get some great SHINE as well...... Overton Square / Beale Street yep fun times......
lol Max, you mean Airdale......er or nosepicker :D
( our friend Ren, gets to frequent the A-4 simulator every now and then, he's got connections , and he lives near there, lucky dog )
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Originally posted by MrDick
6 parts to Jet engine
inlet to diffuser - free stream
diffuser exit - compressor entrance - free stream slowed, pressure raised
compressor exit - burner entrance - pressure raised (work done)
burner exit - turbine entrance - fuel burned temperature raised
turbine exit - nozzle entrance - temperature lower (work extracted)
nozzle exit - pressure lower velocity raised thrust produced
temperature, presssure, velocity, mass are distinct at each location.
-MrD
Not quite how I was taught in FAR-147 school, but fairly close.
An easier way to think of it is the 5 events of an internal combustion engine:
Intake, compression, ignition, power, exhaust.
In a recip they happen at different times in the same spot (Dont even THINK of mentioning Wankle-type rotaries like the Mazda Powersport. They're an oddball.)
In a jet, it's at the same time, in different spots. And in the order I mentioned is about the order it happens in.
Intake in the front, compression in the compressor section (or sections), ignition in the combustion or 'hot' section, power at the turbine wheels, exhaust at the back end.
For a reheater, you have a ramjet at the end of the turbojet/fan, so the exhaust stage for the turbine becomes the intake stage for the reheater section. The same events occur, though usually in a much more confined space (the distance between compression and combustion can, in some types, be measured in inches).
EDIT: Foxy STILL cant spell...
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We had to compute temp, press, velocity, mass rate of change and density at each section (ie. p1, p2, p3, p4, p5, p6) and thrust in jet propusion in engineering school, given free stream Mach, p2/p3 (compressor ratio) etc...
But that's all a distant memory since I work in the software industry :).
-MrD
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what happened to suck, squeeze, bang and blow?
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Originally posted by TequilaChaser
no offense, MrDick, I guess the US Navy mistaught me when I went thru AD A-School ( Jet Mech ) at NAS Memphis ( Millington ) back in the early/mid 80's.......
TC
Let me guess..Suck, Squeeze, Bang and Blow? :)
Ooops, just saw Golfer's post..please ignore.
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Originally posted by Max
C' mon TC....everyone knows that squids don't know nuthin when it comes to flyen
It's not their flying, it's what they call a landing :lol
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Ww and Tc,
I was also at NAS Millington, '75-76, avionics, caged up with the rest of the Jarheads. The one thing I remember most vividly occurred in Dec '75 just after I'd graduated one of my courses. A buddy and I were held up at gunpoint by a local impersonating a swabby asking for a lift to base. It was payday and he thought he was going to knock off two easy wads of cash. We had about $4.25 between us. Anyway, we managed to pursue the guy and his get-away driver all the way from Millington to Memphis on 51, at 85+ mph. The engine of their sorry Olds blew in Memphis, just after I'd hit their car with a railroad spike my buddy had in his glovebox. We called MPD and put the guy behind bars for several years. People were calling us "Starsky and Hutch" lol. O yes, the zeal (?) of youth. Beyond that it was a nice area – yeah, even Graceland.
All the best.
Cement