Forum: Technology

Some here know I am skeptical about the usefulness of thrust-vectoring (TV) for combat maneuvering. I think TV would be most useful for short landings. The only situation in combat where perhaps TV will be useful would be in a 1 vs. 1 dogfight, which would be extremely rare nowadays.

Am I missing something?

Both Russia and the US have conducted extensive studies with TV. Without considering the Harrier, the US has tested (that I know of) with the F-15 ACTIVE (2-D, 3-D), F-18 HARV, F-16 MATV, X-31, X-32, X-36 and F-22.

I think they first tested either on a Skyray or a Tiger, can anyone confirm?

Despite extensive testing, very little of this technology has made it out (F-22, Su-35?). Other European fighter manufacturers expressed intention to incorporate TV retroactively to their fighter (Eurofighter, Rafale, Grippen) but it seems that their interest has waned. I take this as an indication that other technology such as a good helmet mounted sight + missile combo will be far more decisive and cheaper.

To end, I view TV as a giant feel-good for the pilot with very limited practical use. Am I wrong?

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Pat, It depends. TV is a huge bonus in any aggressive, high-g maneuvering. You're right in that it is a huge "feel good" to me, but do I really need it? If I understand what you're asking, it is whether or not this type of maneuvering is needed. As a -16 pilot, I would love to have that capability but bottom line is that we haven't ended up in that situation very often - like you said. Our HMCS with the 9X, AMRAAM, & SNIPER should make it unnecessary to get TV. You can see that choice in the non-selection of TV in the F-35.

(BUT I STILL WANT TV NOZZLES)

Thanks for the reply VprWzl. I know what you mean; we all like having an ace up our sleeve even if we will never need it. TV makes fighters be better fighters, even though it would only be usefull when all else fails.

I'm still surprised it made it onto the F-22. Without TV, the exhaust could have shielded better in the fuselage, contributing more to the overall stealth (a la YF-23). Maybe TC or calhoun can shed some light on this... I think embedding the exhaust within the airframe had something to do with choosing 2-D over 3-D. I'd like to know if TV has helped the F-22 win any WVR engagements were the opponent has helmet mounted sight + missile combo.

Pat theres some really good arguements against anybody using it in a full scale production fighter.

1. Its expensive. performance costs money and money is hard to come by for most countries. Even we have trouble finding it now and again, which is why helmets + HOB heaters are so appealing.

2. Its heavy. Your moving thrust, thats gonna take alot of force and alot of heavy material. Its not as simple as just sticking a new engine in a jet, your changing the Weight and Balance, adding to the hydro system, the list goes on and on. End of the day you got a lot more empty weight in a plane which on something like the viper or Hornet may be detrimental in the long run.

3. Its more to maintain. We live in the most money rich military in the world, and we have our share of "Hanger Queens." Now try and put yourself in an airforce where the money is alot harder to come by. This is something Im interested to see with India getting TV Flankers, I wanna see how long it takes before they stop working because they cant or they dont want to. Its just one more thing that you may not need in a theatre but your wasting manpower on to keep it working. Can you imagine how many more man hours would be required on a jet like the Tomcat, which is seemingly always broke, it just doenst make sence to add something like this.

Good arguments Lawman. I've done some web reading on "fluidic thrust vectoring" (my google search words) that would negate moving parts in the exhaust. Be it applied limitations or overall usefulness, I don't see this being applied either.
I'm all for giving pilots what they want, even if it is expensive TV. Like you said, there is a delicate balance between the benefits and the added cost and weight. And I'm not upset F-22 having TV, it will probably make better use of it since the cost and weight were factored into the design. I'm just surprised politicians went for it, because the advantages are small.

Politicians aren't always the greatest. A lot of them do go for things that benefit them the most or guaruntee them to be elected next term.

Some very good points are being made here, practical ones. I believe we have reached our tactical limits with respect to thrust vectoring requirements. We need what we have and that will be it for quite a while for now.

As far practicality goes, that is what research and development is for. We know what we have to have and should the need arise we can retrofit if needed, thats for all the experimentation with TV and all our inventory. The F/A-22, F-35, and AV-8B need it. As far other avenues go; axio-symetric, converging/diverging ducts will into the play into the future. By that time, TV cost procurment will go down, lighter weight materials will come into play; wait and see. No need to fret over this.

The TV was put on the Raptor, not necessary for dogfight (theraptor is not supposed to do this), but for better maneuvrability when flying fast and high. At 1.6 M and 18,000 m, the classic flight controls are not enough to provide a 6G turn; TV can do this. Also, when turning at these speed the deflection of the control surfaces will induce drag; a small angle deflection of the TV nozzles will provide the Raptor with a high sustained turn rate, without drag.

Very good point cru, it will (TV that is) will be terrorizing in a dogfight none-the-less. Case in point the AV-8B, during excersizes where jets from other services participate with the Harrier in ACM, the Harrier will beat you the first time, everytime, until the debrief, then everyone will learn that fuel and engine count will eliminate the need for any further engagement once the first maneuver is initiated by the Harrier, like I said, it will beat the you first time, everytime, if not, it will out-accel anything on the planet until .88 where then most fighters will catch and beat you then.

As an air-to-air machine, the Harrier and it's thrust vectoring is formidable.

The raptor, well, it can probably confuse the living daylights out of any opponent up-close with TV. Lets wait until we see some up-close footage of ACM with TV and any other jet. I'm afraid because of the TV, there will be no competition whatsoever with the Raptor. Lets stop being so pessimistic about TV, the Air Force finally bought into it after analyzing what the Harrier has done for the Corp for years. See my previous post on this forum!

Speaking of thrust vectoring, is there any performance gain or loss for 3d (X-31) vs. 2d (F-22) thrust vectoring?

Forum: Technology

Thrust-vectoring usefulness