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View Full Version : OT: can anyone explain vector-thrusting?



XyZspineZyX
07-17-2003, 01:43 PM
first of all; plz mods; don't lock this thread (yet) /i/smilies/16x16_smiley-wink.gif

I heard that new engines with the above capability can reduce their stall speed drasticly (half of normal stall speed), making landings (particularly on aircraft carriers) safer and easier...

my question is; what is it actually? is it some device that can be 'attached' to any normal jet engine? what gives ? /i/smilies/16x16_smiley-wink.gif thanks!

XyZspineZyX
07-17-2003, 01:43 PM
first of all; plz mods; don't lock this thread (yet) /i/smilies/16x16_smiley-wink.gif

I heard that new engines with the above capability can reduce their stall speed drasticly (half of normal stall speed), making landings (particularly on aircraft carriers) safer and easier...

my question is; what is it actually? is it some device that can be 'attached' to any normal jet engine? what gives ? /i/smilies/16x16_smiley-wink.gif thanks!

XyZspineZyX
07-17-2003, 01:48 PM
What does vector thrust have to do with WWII eastern front, anyway? Vector thrust is accomplished on the Harrier by using four separate exhaust nozzles that can be positioned varying degrees, from straight back to straight down. Engine exhaust pushes it up for VTOL, then the nozzles slowly move back to push the airplane forward like a normal jet. The new JSF, at least the marine version, uses a normal exhaust in the back, but also a diverted exhaust mid-frame that can direct thrust down, and push the jet up. That's really basic, I know, but if you want to know more, do a search for either of the two above airplanes; I'm sure you'll find a site that explains it better.


Tim Schuster
8MXS Inspection Section
Kunsan AB, Korea

-Defend the Dock!
-Accept Follow-on Shifts!
-Take the Fight Upstairs!

Zayets
07-17-2003, 01:49 PM
What new engines? The goodies that I've heard off so far are:
- head on shooting toned down
- bomber gunners snipe toned down
- ground , naval AAA toned down
- flying low enough will stir the dust/water
- the jug is an "editor choice"

Stall? Heard that is pretty easy to stall now. I just wait the patch.
Zayets out

http://www.emicad.nl/~justdoit/il2/logo.jpg

XyZspineZyX
07-17-2003, 01:50 PM
The jet nozzles can move independently and effectively point more to the sides up down etc. I know it effects manouvreability and likely the stall , but less certain how it would be used in a carrier landing ?

XyZspineZyX
07-17-2003, 01:57 PM
I told it this was OT /i/smilies/16x16_smiley-wink.gif

I was watching (diagonally lol) a show on TV where test pilots were training with a F/A-18 hornet upgraded with vector-thrusting engines. with this vector thrusting, the stall speed was reduced to 190km/h. you could see him fly (on tv) at very low speed, with gear extracted and was tilted 35 degrees backwards. with a 'normal' jet engine, you would have stalled and crashed by now, but since it was vector thrusting (I imagine he directed some of the thrust downwards to counteract the gravity) thereby not stalling but flying.

being able to fly at lower speeds should be considered a safe step forwards for landing, as it reduces the length of airfield required and ofcourse speed upon touchdown. this is ofcourse very handy for aircraft carrier landings. where you have a margin of 45cm... (that's roughly 10" for all you imperialists out there /i/smilies/16x16_smiley-wink.gif )

what I was wondering is that this vector-thrusting device was just a modification of the engine or a seperate device doing it's share.

XyZspineZyX
07-17-2003, 01:58 PM
You mean the new generation of jets like the SU37 and F22 ???

..... it is simply a system to redirect part of the thrust from the engines sideways or downwards to allow extreme manouvres that would otherwise be impossible

XyZspineZyX
07-17-2003, 02:00 PM
WTE_Galway wrote:
- You mean the new generation of jets like the SU37
- and F22 ???
-
- ..... it is simply a system to redirect part of the
- thrust from the engines sideways or downwards to
- allow extreme manouvres that would otherwise be
- impossible
-

ah yes. that's what I mean. but the core of my question is:

does a complete new engine have to be built for the plane, or can it be 'upgraded' as you will; just plug this device on the rear of the jet and voila. or is it a complete new engine?

XyZspineZyX
07-17-2003, 02:03 PM
In conventional takeoff/landing aircraft (F22, Sues) most of it is nozzle technology rather than the engine itself, certainly 2D (in the vertical plane) vectoring is a fairly easy bolt-on on the back of an existing engine.

VTOL aircraft need a lot more alterations to deflect all thrust downward to counteract gravity. Engines like the Pegasus in the Harrier and the lift fan/jet combo in the JSF are built from scratch for that purpose.


SSS

Edit : Ignore me, the chap below seems to know more about the subject than I /i/smilies/16x16_smiley-wink.gif



Message Edited on 07/17/0301:07PM by SpinSpinSugar

XyZspineZyX
07-17-2003, 02:05 PM
Trying to "plug in" something like that is an engineers nightmare. Most, if not all, vector thrust capable modern jets are purpose built that way. I do know of an F-16 that was tested with a vector thrust nozzle, but I'm pretty sure it wasn't attached to the GE engine (or the lousy Pratt & Whitneys) that is most commonly used in F-16s. The airframe stress that comes along with vector thrust makes a "plug-n-play" version if not impossible, then darn improbable. The modifications needed to turn a jet into a VTOL or VSTOL would cost as much as just building a newer jet. That's why we now have the JSF, or F-35 (I think). Besides, most jets (american anyway) are so old it's not worth upgrading them that severely anyway. I know all the planes I've worked on over the years (F-111, F-117, F-16) are ancient. Believe me, most jets are hard enough work to keep flying just as they are now. VT is a mechanics nightmare too.


Tim Schuster
8MXS Inspection Section
Kunsan AB, Korea

-Defend the Dock!
-Accept Follow-on Shifts!
-Take the Fight Upstairs!


Message Edited on 07/17/0301:09PM by Aardvark892

XyZspineZyX
07-17-2003, 02:09 PM
my understanding is with the sukhois it generally involves replacing the engines with a specifically made thrust vectoring engine ... however there is some work being done on thrust vectoring nozzles which may allow modification of existing engines possibly on the euro-fighter for example

this is not my area .. nor is it the best forum to get accurate answers on this sort of stuff

XyZspineZyX
07-17-2003, 02:12 PM
My favorite thing about the F-22 is the secure data link between F-22's. Say you have two F-22's going up against 4 Su-27's. One of the F-22's is 20 miles or so ahead of the other one, with his radar off. The 22 in the rear has his radar on, as well as the 4 Su-27's. The 27's and the one 22 in the rear can pick eachother up on radar, but theyr'e out of missile range. The rear 22 sends the target info over a secure data link to the 22 in front (who is in missile range of the 27's). The 22 in front launches his missiles at the 4 27's, who didnt even know he was there. Game over.

Its soooooooo coooooooooool!!!


http://www.lmaeronautics.com/gallery/products/combat_air/f22/f22_press/f22_02/f22pr020828_lr.jpg




How many boards could the Mongols hoard if the Mongol Horde got bored?

XyZspineZyX
07-17-2003, 02:15 PM
thanks for the replies guys.

and what bamatt told is indeed very cool! thanks bamatt for sharing! /i/smilies/16x16_smiley-happy.gif

XyZspineZyX
07-17-2003, 02:30 PM
Bamatt wrote:
- My favorite thing about the F-22 is the secure data
- link between F-22's. Say you have two F-22's going
- up against 4 Su-27's. One of the F-22's is 20 miles
- or so ahead of the other one, with his radar off.
- The 22 in the rear has his radar on, as well as the
- 4 Su-27's. The 27's and the one 22 in the rear can
- pick eachother up on radar, but theyr'e out of
- missile range. The rear 22 sends the target info
- over a secure data link to the 22 in front (who is
- in missile range of the 27's). The 22 in front
- launches his missiles at the 4 27's, who didnt even
- know he was there. Game over.
-
- Its soooooooo coooooooooool!!!
-
-

Datalinks are very common in most of the new lines of fighter craft and are fitted to older aircraft also. The Eurofighter, the Gripen and the Rafale are all equipped with Datalinks. Another thing that can be done in an Eurofighter, is that the unit commander can from his fighter designate targets for his wingmen, therefore preventing that two fighters fire on the same target. I don't know if this capabability is also available in other fighters, but I would think so, already because of the increased efficiency in ammo usage.

Oh, and here a link to a page about the Eurofighter, scroll down to Thrust Vectoring Control, there is a little explanation about TV in general.

http://www.eurofighter.starstreak.net/Eurofighter/engines.html

<p align="center">http://hometown.aol.de/Deathbrng/Sigfinal.jpg</p><p align="center">'Hmmm? I wonder what the red button is for........'</p><p align="center">HL Nick = BLUE_Schnitter</p>



Message Edited on 07/17/0303:35PM by Der_Schnitter_t

XyZspineZyX
07-17-2003, 02:34 PM
Rafale ???

Isn't that a french (cough) "fighter" ?????????


cc

XyZspineZyX
07-17-2003, 02:42 PM
Coon-Chow wrote:
- Rafale ???
-
- Isn't that a french (cough) "fighter" ?????????
-
-
- cc
-
-

Yep, looks ugly like hell too, IMHO.



<p align="center">http://hometown.aol.de/Deathbrng/Sigfinal.jpg</p><p align="center">'Hmmm? I wonder what the red button is for........'</p><p align="center">HL Nick = BLUE_Schnitter</p>

XyZspineZyX
07-17-2003, 04:00 PM
Der_Schnitter_t wrote:
- Oh, and here a link to a page about the Eurofighter,
- scroll down to Thrust Vectoring Control, there is a
- little explanation about TV in general.
-
- <a
- href="http://www.eurofighter.starstreak.net/Eurofi
- ghter/engines.html"
- target=_blank>http://www.eurofighter.starstreak.ne
- t/Eurofighter/engines.html</a>

ah. thank you very much for that link. it's a very good one! /i/smilies/16x16_smiley-happy.gif

XyZspineZyX
07-17-2003, 04:03 PM
I saw the sukhoi 37 with thrust vectoring, flying at Le-bourget /i/smilies/16x16_smiley-happy.gif

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2 For with what judgment ye judge, ye
shall be judged: and with what
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measured to you again.

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