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I just thought I'd spawn some discussion regarding the JSF. To start things off here are the main advantages I see of the JSF over the AV-8B. First and foremost, its engines are built in a way that leaves less of a heat signature. Second, the engines are more powerful and fuel efficient, also making the JSF supersonic. Third, the JSF is more maneuverable and would be more survivable in a dogfight. Last but not least, the JSF has better avionics and better support for sustained STOVL operations.

Add in some more, I'm sure I'm only touching the tip of the ice berg here. cheers.

<img src="http://www.lmtas.com/gallery/products/combat_air/x35/x35_press/x35_01/thumbnails/X35080503_tn.jpg" border=0>

"The cost of peace is eternal vigilance". -Thomas Jefferson

not much to argue with there, the JSF will be superior to the AV-8 series. I believe the JSF will have a HIGHER IR sig than Harrier(at leaste from the engine, but MAYBEE less in cruise mode) but that sig will be in a MUCH more desirable area (the rear of the aircraft rather than the middle) the Harriers took a beating in ODS cause even a "near miss" on the 4 central(2 cold 2 hot) thrust nozzles put a MANPAD well within the framework of the rest of the aircraft. I'm not sure how different the maneuverability will be cause the JSF wont be able to "VIFF" as the Harrier can, and I dont know how effective "VIFFing" was for Harrier in the first place. But I know WATCHING video of a Marine pilot VIFFing left a knot in my stomach, the first time I saw it LOL

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

Booms,

Good point... I should have worded that differently. The actual heat output of the engine will be about the same... infact the JSF might even put out more because its engine is in the 29K thrust category. What I should have said is that the engine placement reduces the risk of getting hit. As for manueverability... the F-35B is more aerodynamic than the harrier and later models may include thrust vectoring engine nozzles. cheers

"The cost of peace is eternal vigilance". -Thomas Jefferson

The JSF's engine produces 37,500lbs of thrust at full AB.

"We shall leave no man behind"

Whoa, 37K category? wow... ++ heat signature then... at least its not placed in the mid-section of the aircraft. Thanks again for the info M21.. your contributions are always appreciated. take it easy bro.

"The cost of peace is eternal vigilance". -Thomas Jefferson

I am not so sure lbs of thrust is completely relative to the size of the IR signature in todays advanced powerplants..........It may be to a degree, but their are other factors that reduce it despite impressive T:W ratio, and raw thrust. Any input from the experts on this?

If your not having fun, your not doing it right!

Yeah heres some Advice, Stay away from Manpads. Trust me on this<img src=icon_smile_wink.gif border=0 align=middle>

"<---Jesus Powers My Hotrod---<<<"

JSF!!!!!!!!!!!!!!!!!!!
JSF!!!!!!!!!!!!!!!!!!!
JSF!!!!!!!!!!!!!!!!!

the second greatest plane in the world
[best being the A-10]

i got a bad feeling about this

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
I am not so sure lbs of thrust is completely relative to the size of the IR signature in todays advanced powerplants..........It may be to a degree, but their are other factors that reduce it despite impressive T:W ratio, and raw thrust. Any input from the experts on this?If your not having fun, your not doing it right!
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(not an expert but) YUP, just look at an airliners 60,000lb+ fan verses any fighter engine in AB, LOTS of variables, AB or no AB, Bypass ratio, "thermal mitigation" are parts of the engine/tailpipe cooled by air or fuel? How close to the skin is the engine? The F-15 cant even keep paint on the lower skins because of the temps(what I read anyway)



"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

Edited by - boomer on Mar 04 2003 12:14 PM

_________________
The only time you have too much fuel is when you're on fire.

Lower engine bay panels on the F-15 are titanium and have never been painted, nothing to do with the heat of the engine. The "turkey feathers" (outer nozzle seals) were removed years ago because of heat build up and the huge amount of maintenence that had to do with maintaining them.

"face it....perhaps your only purpose in life is to serve as a warning to others!"

A10 stress,

I read somewhere that the F-135s are more fuel efficient than the PW F100 series engines, especially the 229. Can you confirm this because I don't remember where in the heck i read it. More fuel efficient doesn't necessarily mean that it burns less fuel, just that it uses it more efficiently... burning less fuel per unit volume than the F100. Thanks for the info guys...

JSF!!! the best plane in the world for the Multi-Role spectrum!

"The cost of peace is eternal vigilance". -Thomas Jefferson

Edited by - buzz2182 on Mar 04 2003 2:11 PM

thanks M&M , I had read somewhere that they werent painted cause of the heat.

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

No problem boomer always glad to help.

"face it....perhaps your only purpose in life is to serve as a warning to others!"

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
Lower engine bay panels on the F-15 are titanium and have never been painted, nothing to do with the heat of the engine. The "turkey feathers" (outer nozzle seals) were removed years ago because of heat build up and the huge amount of maintenence that had to do with maintaining them.

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<img src="http://212.67.202.161/~steved/boardlinks/0020.jpg" border=0>

_________________
\"A good plan violently executed now is better than a perfect plan executed next week. \"

George S. Patton

A-10,

Thanks for the info bro, thats actually pretty interesting stuff to me (fellow geek). What I was wondering is how efficient the F135 is compared to the PW F100 or the GE F110...I read an article on another site that claimed that the F135 burned less fuel/amount of thrust /hr at 36K than the GE or PW series of engines that the F-16 and F-15 use.

So, you are saying that a low bypass engine (such as the F100) burns less and is just as efficient... which is all I need to know <img src=icon_smile.gif border=0 align=middle> I consider you a credible source. Again, this was an uncomfirmed source as it was on a message board similar to this one. Useful information though... I use a similar formula when I'm calculating fuel consumption on Cross-Country flights. cheers man.

"The cost of peace is eternal vigilance". -Thomas Jefferson




Edited by - buzz2182 on Mar 06 2003 02:25 AM

So essentially if i did some "hobby work" I might find that the F135 is 2% more efficient <img src=icon_smile.gif border=0 align=middle> I agree. Thanks for all the info man, your expertice is always appreciated. cheers.

"TACAIR, the Air Force Version of Fast Food."

Stress, I hope you dont mind, but I'm litterally going to highjack your post over to that F-4K thread LOL

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

Hmm... More questions about LockMarts competance. 20% sounds like a BIG number to "discover" at this point in the program. Remember that LockMart ALSO "discovered" that AFTER the contract was won on the X-33(?) SSTO space plane, that by golly by gosh the darn thing wont fly in a wind tunnel!!!

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

Boomer- competence, or honesty?

Hmmmm...

"We shall leave no man behind"

Edited by - m21 sniper on Mar 18 2003 11:11 AM

I hear ya stress believe me, but the JSF has been one program that has thrown away "wish lists" and performance to keep the bottom line ($) and comonality in line as much as possible( I remember a 5 sider saying "we'll sacrifice anything in JSF to keep costs in line"). I said here(I think) after the JSF award was given, that the production model could bear little resmblance to the protos cause they were basically just propulsion demos(McD got hosed by getting stuck with that "gas fan" thing LOL) with a HOPEFULLY stealthy moldline. The STO/VL version has never been what the Marines wanted ( but probobly need) they wanted a bomb truck with STO/VL and didnt want stealth or "gee whizz" to pay for or maintain. Not going "conspiracy theory" either just more of the "buy then fix" hijinx again, much like Osprey. But weight probs in a STO/VL is very much a pass/fail situation. Stress with your knowledge I KNOW your well aware of how a "more weight, more power, more fuel" situation can mushroom into a mess that will never get off the ground(literally LOL) and VTOL just magnifies all that. Protos are notoriosly overweight cause truthfully the companies really dont know what thier doing till they find out what breaks and what is overbuilt and cobbed together. HOPEFULLY that is exactly the prob and they'll be able to shave a lot of weight out of the structure.

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

I've heard that various F-35 variants are going to be receiving thrust-vectoring technology. Would that still apply to the F-35B? I was thinking about the logistics of having an engine that tilts down and can incorporate thrust vectoring... sounds sketchy. Any comments?

"TACAIR, we deliver, you eat dust"

Not the B, not so far as i know.

The TVC is for the A and C models.

"We shall leave no man behind"

Thats what I thought... any time frame for the implementation of the TVC? thanks for the clarification.


"TACAIR, we deliver, you eat dust"

yeah, the Yakovlev designed tailpipe for the B would preclude any chance of TV. If the initial F-35s(A and C) dont have TV , I dont see them getting retro'ed for a long time, and if they DO get TV it would be of the coaxial variety not the 2D like F-22 has, 2D would require a complete re-design of the aft fusalage, that motor is HUGE!!

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

http://www.codeonemagazine.com/photos/g ... oto14.html
Hows this for thrust vectoring? This is a pic of the F-35B.

"face it....perhaps your only purpose in life is to serve as a warning to others!"