By: firebar
- 28th September 2006 at 14:37Permalink- Edited 1st January 1970 at 01:00
Go watch the video.
I have a video of F-14 doing Cobra maneuver , to about 80 degrees, during tests in 70-es.
But service F-14 can not go beyond 50 degrees.
That is the point.
By: firebar
- 28th September 2006 at 14:47Permalink- Edited 1st January 1970 at 01:00
Wow, you really can't read can you?
There are no public numbers on the Raptor's transient AoA
.
Of course there are. Read Aviation Week. It had 60 degrees max transient. There are many articles about that.
Do anybody read Aviation Week here ?
From the video, in a normal service Raptor, the pilot was able to reach about 120 degrees AoA. It is not a test plane. This was at an airshow in a jet loaded with 8 missiles and almost full tanks.
We can not see that from the video.
Is there any source to confirm that ?
Raptor pilots say that they have no problem doing any of the post-stall manuevers of the Flanker series.
You are too optimistic about Raptors abilities, are you?
For one thing, it can not do a Super Cobra, like SU-37. A full turn about lateral axis.
Note that it was demonstrated on Farnborough airshow.
I want a Raptor to do it.
New
Posts: 12
By: Doggy
- 28th September 2006 at 15:46Permalink- Edited 1st January 1970 at 01:00
Firebar,
I do not know where you get your aeronautical background or even your information but you seem to be incorrect.
Let's start with the F16.
You stated:
The perfect aerodynamics is far more important than Fly-by-wire controls.
Look at F-16. It can not do more that 26 degrees because it aerodynamics do not allow it. Despite Fly-by-wire. This can not help.
Or look at Tornado ADV. The same applies to it.
Whilst you didn't have much credibility to begin with, do you actually know the reason why it is limited 26 deg AOA (BTW, you can override this during a deep stall condition for recovery).
Unstable, AFT Cg. The FLCS keeps the plane flying level. If it was there it would flip OVER. It has nothing to do with aerodynamic capability of the aircraft.
----
There are no Alpha limits on the Raptors, you only use AOA that you can CONTROL which means the ability to maneuver the plane at these high AOA.
The Flanker and even the Fulcrum suffers the same problems at high AOA. They have don't have that much control in the 'post stall region'. The MPO switch enabled, low speeds, light weights and changed Cg, give these planes the ability to put their nose up past vertical (90-100 degrees) in less than three seconds. While losing a lot of speed, control authority goes to NIL as you get closer to ZERO airspeed. The pilot get the the aircraft's back down as prolonging this maneuver is a BAD thing because the plane is already descending. So with some usable airspeed left, he attempts to lower the nose via stick and flipping the MPO switch (changes stick gains). Once the AOA lowers, he'll have more authority to maneuver the airplane.
This maneuver isn't about aerodynamic qualities of an airframe but the unstability margin.
At 60 Alpha, the F22 has more control authority than the majority of operational fighters. This includes the Flanker, Fulcrum, S Hornet, Hornet, .etc.
What's impressive is that there is still control when holding bank. Majority of all aircraft (even the F18s) at high AOA begin to wallow once you start add in banking the Raptor does NOT.
By: bring_it_on
- 28th September 2006 at 16:01Permalink- Edited 1st January 1970 at 01:00
There has to be limit to Raptors AoA. The only fighters which have no limit of AoA are SU-37 or SU-30 MKI, which have TVC and performed 360 degrees, full turn about lateral axis.
The Raptor can not do it despite TVC.
Just like it couldnt do the COBRA about a year ago . Firebar i wasnt talking about limitations like what you mentioned , do IAF pilots routinly do kilbits in DACT ?? the limitations i was talking about were G load and AOA limiters which are placed during peacetime to preserve airframe life .
Regarding 360 degree instantanius back flips the word is still out , DOZER the demo pilot for the raptor said that he has seen most of flanker displays and that the raptor can pretty much the same with its TVC , and that they wont be displaying its full Airshow manueverability untill 2008 when they actually set out to a big air show the likes of Farnborough ( probably RIAT ) .
There has to be limit to Raptors AoA
why ? Because it isnt designed by sukhoi???
But every aircraft has its own limit beyond which it will departure from controlled flight.
For now, the Raptor has 60 degrees limit for service aircraft, if it is not lifted recently. The test pilot maneuvers do not account.
Is there any recent source to prove otherwise ?
How about combat pilot testimonials ( visit fencecheck codeone etc) where the COMBAT pilots ( not test pilots for crying out loud) have said that it is stall and departure free at all AOA just like the VISTA/MATV and X-31 and in COMBAT CODED RAPTOR it can sustain 60 degrees AOA .
Why do you say AOA for airshow only?? the raptor that performed those was FULLY OPERATIONAL IN AN OPERATIONAL SQUADRON , CAME OUT OF SQUADRON DUTY TO PERFORM THE SHOW AND PERFORMED IT WITH 8 MISSILES AND ENOUGH FUEL TO FLY TO AND FROM THE DESTINATION . THE PILOT HAS REPEATEDLY SAID THAT NO MODIFICATION WAS MADE TO THE JET!!!
It can not do more that 26 degrees because it aerodynamics do not allow it. Despite Fly-by-wire. This can not help.
ofcourse VISTA/MATV were not really F-16's now were they?? how could those aerodynamic configurations be usable at all AOA , perform cobras etc etc
With MiG-29 and SU-27, the Russians managed to built aerodynamicaly perfect fighters.
Even without TVC they are virtualy departure proof, and controllable to more that 90 degrees AoA. This is an outstanding feature.
No doubt that is why they are the standard evryone else tries to measure up to !!
But service F-14 can not go beyond 50 degrees.
Where did u not get the fact that the pilot has said that the F-22 has perfromed the COBRA in operational conditions with 8 missiles and a representative fuel load , and no special modifications were made ??
Why is it so hard for you to believe something that has been laid out so simple!!!
It had 60 degrees max transient.
No it was 60 degrees max sustain , read the umpteen books on the ATF and Raptor !!
We can not see that from the video.
Is there any source to confirm that ?
If you look hard enough you can see the tail codes quite clearly from this and other videos and the PILOT WHO FLEW THIS HAS MADE TESTIMONIALS REGARDING THE WEAPONRY WHICH HAVE BEEN POSTED IN THE VARIOUS THREADS , HE IS A MEMBER AT FENCECHECK AND VISITS THERE , HOWEVER HE VOULUNTARILY ASKED SOME OF HIS MATERIAL TO BE REMOVED BUT THE MATERIAL IS AVAILABLE HERE , HE HAS ALSO SAID IT IN A ARTICLE PUBLISHED AND POSTED BY ME - LOOK FOR IT AND YOU'LL SEE IT !!
I want a Raptor to do it.
i HAVE A list of things i want a raptor to do , but the raptor as a routine is only going to do what the demo pilot wants it to do period . personally i dont like DOZER's cobra ( the callsign of the pilot is dozer) , i prefer the snap on and snap off cobra of the flanker much better but dozer likes it slow and likes to wait just a tad bit ( mind you according to him he is still refining the cobra and it would be a lot different with time) to demonstrate that the noze doesnt snoop around and remains stable even at AOA of 120 degrees or so . I also want him to do a KILIBT and what not but too bad we dont have the right connections ;)
By: sferrin
- 28th September 2006 at 16:12Permalink- Edited 1st January 1970 at 01:00
Firebar sees what he wants to see. Show him something that contradicts his beliefs and he tries to put a spin on it in a vain attempt to make it fit his own wishes. Frankly I think it's a waste of time even responding to him.
Shower was joined at Oshkosh that day by Col. Thomas Bergeson, who entertained us with high-speed, excruciatingly loud passes in another Raptor while Shower flew off to collect his airplane for its next stunt. One of them he calls "the helicopter." The airplane is falling straight down, but rotating in a spin. This is one of Shower’s favorites—the guy must have a stomach made of titanium.
The jet can sustain over 30 degrees per second of yaw, he marvels. "Thirty degrees per second in an F-15? The beeper’s going off and I’m in an uncontrollable spin. But in an F-22, it’s totally controllable, and you’re just going ‘dit da dit da duh,’ " he hums. "And I’ll push the pedal the other way, and it will just stop and go 30 degrees in the opposite direction." Shower laughs in gleeful disbelief that an airplane will allow him to have this much fun.....
He’s seen demos and videos of performances by the Russian MiG 29 and Sukhoi Su 35, and admits that their maneuverability is probably on a par with the F-22. "I can do everything they can do and vice versa," he says. "We can all do some pretty neat stuff. But I love this part of it: That’s all they have. They don’t have the stealth , they don’t have the supercruise, they don’t have the integrated sensors, the avionics. We have an aircraft that does everything a fighter pilot has ever wanted to do. It has it all—you can tell by the price tag," he says, (about $137 million per copy, or $338 million if you count in all the Air Force's research costs).
For their performance, which started at 2:40 p.m., Shower and Bergeson took off from Langley, 800 miles away, at about 1:25. "We were going slow," Shower says. "We were only doing about .9 Mach. Over the continental United States, there’s only a couple of places we’re allowed to go supersonic so we don’t scare everybody. But we did the math and figured we could be there if we supercruised in about 25 or 30 minutes."
Please dont jump the gun and say that it can only sustain 30 degrees of AOA as he is talking about yaw rates!!
OTHER COMMENTS THAT HAVE BEEN MADE BY SHOWER (AKA DOZER)
when we fly the Raptor even in airshows, it's a stock jet, full of gas, IN it's combat configuration, you can't imagine what a difference that truly is - I'd like to see a Super Hornet perform the same demo with 8 pylons & missiles + a fuel tank & EA pod hanging off the jet, or the Flanker or anything else). In other words - add up all the modifications, additions, changes, software, hardware, testing, etc. etc. etc., and you begin to see why the
Frazier can provide you the entire article so contact him!!!
By: sferrin
- 28th September 2006 at 16:24Permalink- Edited 1st January 1970 at 01:00
No doubt this will start another debate/firestorm but. . . .
For their performance, which started at 2:40 p.m., Shower and Bergeson took off from Langley, 800 miles away, at about 1:25. "We were going slow," Shower says. "We were only doing about .9 Mach. Over the continental United States, there’s only a couple of places we’re allowed to go supersonic so we don’t scare everybody. But we did the math and figured we could be there if we supercruised in about 25 or 30 minutes."
800 miles in 30 minutes would be 1600 mph
800 miles in 25 minutes would be 1920 mph
By: bring_it_on
- 28th September 2006 at 17:08Permalink- Edited 1st January 1970 at 01:00
the 800 miles away was probably the distance on road and might not be the distance " as the crow flies " or it could be i just dont know and dont care to calculate .
By: sferrin
- 28th September 2006 at 23:42Permalink- Edited 1st January 1970 at 01:00
the 800 miles away was probably the distance on road and might not be the distance " as the crow flies " or it could be i just dont know and dont care to calculate .
According to Google Earth Langley AFB to Oshkosh WI is about 799 miles as the crow flies.
By: kilcoo316
- 29th September 2006 at 12:35Permalink- Edited 1st January 1970 at 01:00
Just to answer a few comments in the thread [but I'm well hungover, so could get things a little muddled :D]
- Normally every aircraft has a flight envelope and a departure from controlled flight. However, new aircraft [such as the F-22 and OVT] have carefree handling as a design objective. Basically, this means the pilot can do what he wants in terms of flying the aircraft, and he will always retain a good measure of control authority over the aircraft. Therefore departure from controlled flight is impossible in an F-22 or OVT [or similar such aircraft].
- As far as I knew, the F-16 was AoA limited by lateral stability, its vertical fin induces problems in manouvering. A quick google found this: here. Its well worth a read.
- Also, fluidic TVC... From what I've read its still some way short of the efficiency of mechanical systems, and there are doubts as to whether the deficiencies can be overcome.
- Firebar is right in saying that manouverability is affected more by an aircraft's aerodynamics than its fly-by-wire capabilities. However, he is wrong in saying the F-22 has to have a limit to its AoA. There is no reason why it should.
I was gonna say more, but my head is killing me :o
By: firebar
- 29th September 2006 at 13:05Permalink- Edited 1st January 1970 at 01:00
Firebar,
I do not know where you get your aeronautical background or even your information but you seem to be incorrect.
Let's start with the F16.
You stated:
The perfect aerodynamics is far more important than Fly-by-wire controls.
Look at F-16. It can not do more that 26 degrees because it aerodynamics do not allow it. Despite Fly-by-wire. This can not help.
Or look at Tornado ADV. The same applies to it.
Whilst you didn't have much credibility to begin with, do you actually know the reason why it is limited 26 deg AOA (BTW, you can override this during a deep stall condition for recovery).
Unstable, AFT Cg. The FLCS keeps the plane flying level. If it was there it would flip OVER. It has nothing to do with aerodynamic capability of the aircraft.
Doggy, you have to understand that F-16 is service limited to 26 degrees AoA because it was found that at about 30 degrees AoA it has strong propensity to departure from controlled flight. This often end in a flat spin.
This is aerodynamic characteristic of F-16s unstable configuration.
There is no FBW system which can correct this, and allow more AoA.
Regarding Tornado ADV, it is not unstable, but again, FBW controls can not substitute for a bad aerodynamics.
There are no Alpha limits on the Raptors, you only use AOA that you can CONTROL which means the ability to maneuver the plane at these high AOA.
Every fighter has its AoA limit. Do not delude yourself.
That is max AoA from which it is possible to surely recover the aircraft without departure.
The Flanker and even the Fulcrum suffers the same problems at high AOA. They have don't have that much control in the 'post stall region'. The MPO switch enabled, low speeds, light weights and changed Cg, give these planes the ability to put their nose up past vertical (90-100 degrees) in less than three seconds. While losing a lot of speed, control authority goes to NIL as you get closer to ZERO airspeed.
They have no problems at all. These are only fighters which have such high controllability at high AoA that they are able to demonstrate Tail slide and Cobra maneuvers before crowd in international airshows regularly.
Remember that american pilots say they are amazed with MiG-29s or SU-27s contlollability at high Alpha.
This maneuver isn't about aerodynamic qualities of an airframe but the unstability margin.
Do you understand that unstability has a bad influence on high AoA flights.
At 60 Alpha, the F22 has more control authority than the majority of operational fighters. This includes the Flanker, Fulcrum, S Hornet, Hornet, .etc.
It is your wish.
Do you know that Russian fighters do a Super Cobra and Hook maneuvers, again on International Airshows. These are totaly out of the grasp of F-22.
By: bring_it_on
- 29th September 2006 at 13:26Permalink- Edited 1st January 1970 at 01:00
They have no problems at all. These are only fighters which have such high controllability at high AoA that they are able to demonstrate Tail slide and Cobra maneuvers before crowd in international airshows regularly.
You say that the Su-30++ and Mig-29++ are controlable at any AOA yet in your previous post you say this -
Every fighter has its AoA limit. Do not delude yourself
So whats the AOA limit of a su-30MKI , F-16MATV or a Mig-35 ?? at what AOA do they become Uncontrolable ??
Tail slide and Cobra maneuvers before crowd in international airshows regularly.
There is videographic evidence to show RAPTOR doing TAIL side and COBRA and the WI show had some intrenational exibhitors i believe like HONDA . However if you want high end trade shows the likes of which dont really exist in the US ( big three or 4 like farnbr. , paris , RIAT etc ) then you'd have to wait about 14 months or so before the F-22 goes to one of them according to the demonstration pilot ( Shower)
Do you know that Russian fighters do a Super Cobra and Hook maneuvers, again on International Airshows. These are totaly out of the grasp of F-22.
Again do the russian aircraft hold cobras in a sustained manner ?? Are you sugesting that the Super flanker can sustain 120+ degree AOA ??
These are totaly out of the grasp of F-22.
The pilot demonstrating these manuevrs and who also happens to be the most experienced in service raptor pilot says that he can perform everyone of those manuevers and with time he will do so leading up to the big airshow demos more likely in 2008 - however do except some more snippets at Langley this year . Now we can either believe you or believe the man who flies this jet on a daily basis and is asking every entusiast to just hold a while .
The choices i am sorry to inform you have allready been made by most members!!!
By: firebar
- 29th September 2006 at 13:34Permalink- Edited 1st January 1970 at 01:00
Just like it couldnt do the COBRA about a year ago . Firebar i wasnt talking about limitations like what you mentioned , do IAF pilots routinly do kilbits in DACT ?? the limitations i was talking about were G load and AOA limiters which are placed during peacetime to preserve airframe life .
All right, but ask Israeli pilots which, in F-15s, took part in simulated combat with Luftwaffe Mig-29 in Sardinia, how they fared ?
Note that it was downgraded Mig-29 with tuned down engines.
Regarding service limitations of AoA, this is not imposed as a measure to preserve airframe life.
Every fighter has its own AoA limit, beyond which it is prone to departure.
Look at, for instance, F-18 manual. It says that beyound 50 to 55 degrees AoA, the clean F-18 will surely depart and will end in a Falling Leaf from which escape is almost impossible.
There is no such constraints for Mig-29 or SU-27.
Regarding 360 degree instantanius back flips the word is still out , DOZER the demo pilot for the raptor said that he has seen most of flanker displays and that the raptor can pretty much the same with its TVC , and that they wont be displaying its full Airshow manueverability untill 2008 when they actually set out to a big air show the likes of Farnborough ( probably RIAT ) .
I would say that it is not safe for F-22 yet to demonstrate Cobra maneuver in International airshows. To do it, the fighter has to be absolutely safe from departure. It is not easy to acomplish at 90 degrees AoA.
Where did u not get the fact that the pilot has said that the F-22 has perfromed the COBRA in operational conditions with 8 missiles and a representative fuel load , and no special modifications were made ??
Why is it so hard for you to believe something that has been laid out so simple!!!
I believe it. But this is not enough. The pilot has to be able to repeat this maneuver every time without fear that his aircraft will depart.
Only then it will be ready for International Airshows.
Shower was joined at Oshkosh that day by Col. Thomas Bergeson, who entertained us with high-speed, excruciatingly loud passes in another Raptor while Shower flew off to collect his airplane for its next stunt. One of them he calls "the helicopter." The airplane is falling straight down, but rotating in a spin. This is one of Shower’s favorites—the guy must have a stomach made of titanium.
The jet can sustain over 30 degrees per second of yaw, he marvels. "Thirty degrees per second in an F-15? The beeper’s going off and I’m in an uncontrollable spin. But in an F-22, it’s totally controllable, and you’re just going ‘dit da dit da duh,’ " he hums. "And I’ll push the pedal the other way, and it will just stop and go 30 degrees in the opposite direction." Shower laughs in gleeful disbelief that an airplane will allow him to have this much fun.....
He’s seen demos and videos of performances by the Russian MiG 29 and Sukhoi Su 35, and admits that their maneuverability is probably on a par with the F-22. "I can do everything they can do and vice versa," he says. "We can all do some pretty neat stuff. But I love this part of it: That’s all they have. They don’t have the stealth , they don’t have the supercruise, they don’t have the integrated sensors, the avionics. We have an aircraft that does everything a fighter pilot has ever wanted to do. It has it all—you can tell by the price tag," he says, (about $137 million per copy, or $338 million if you count in all the Air Force's research costs).!
I do not doubt this. I only say that MiG-29 and SU-27 do that maneuvers absolutely confidently in International Airshows, which F-22 can not duplicate yet.
Of course, it is TVC aircraft and when fine tuned, it is going to do it also.
Posts: 875
By: firebar - 28th September 2006 at 14:37 Permalink - Edited 1st January 1970 at 01:00
I have a video of F-14 doing Cobra maneuver , to about 80 degrees, during tests in 70-es.
But service F-14 can not go beyond 50 degrees.
That is the point.
Posts: 875
By: firebar - 28th September 2006 at 14:47 Permalink - Edited 1st January 1970 at 01:00
.Of course there are. Read Aviation Week. It had 60 degrees max transient. There are many articles about that.
Do anybody read Aviation Week here ?
We can not see that from the video.
Is there any source to confirm that ?
You are too optimistic about Raptors abilities, are you?
For one thing, it can not do a Super Cobra, like SU-37. A full turn about lateral axis.
Note that it was demonstrated on Farnborough airshow.
I want a Raptor to do it.
Posts: 12
By: Doggy - 28th September 2006 at 15:46 Permalink - Edited 1st January 1970 at 01:00
Firebar,
I do not know where you get your aeronautical background or even your information but you seem to be incorrect.
Let's start with the F16.
You stated:
The perfect aerodynamics is far more important than Fly-by-wire controls.
Look at F-16. It can not do more that 26 degrees because it aerodynamics do not allow it. Despite Fly-by-wire. This can not help.
Or look at Tornado ADV. The same applies to it.
Whilst you didn't have much credibility to begin with, do you actually know the reason why it is limited 26 deg AOA (BTW, you can override this during a deep stall condition for recovery).
Unstable, AFT Cg. The FLCS keeps the plane flying level. If it was there it would flip OVER. It has nothing to do with aerodynamic capability of the aircraft.
----
There are no Alpha limits on the Raptors, you only use AOA that you can CONTROL which means the ability to maneuver the plane at these high AOA.
The Flanker and even the Fulcrum suffers the same problems at high AOA. They have don't have that much control in the 'post stall region'. The MPO switch enabled, low speeds, light weights and changed Cg, give these planes the ability to put their nose up past vertical (90-100 degrees) in less than three seconds. While losing a lot of speed, control authority goes to NIL as you get closer to ZERO airspeed. The pilot get the the aircraft's back down as prolonging this maneuver is a BAD thing because the plane is already descending. So with some usable airspeed left, he attempts to lower the nose via stick and flipping the MPO switch (changes stick gains). Once the AOA lowers, he'll have more authority to maneuver the airplane.
This maneuver isn't about aerodynamic qualities of an airframe but the unstability margin.
At 60 Alpha, the F22 has more control authority than the majority of operational fighters. This includes the Flanker, Fulcrum, S Hornet, Hornet, .etc.
What's impressive is that there is still control when holding bank. Majority of all aircraft (even the F18s) at high AOA begin to wallow once you start add in banking the Raptor does NOT.
Posts: 12,109
By: bring_it_on - 28th September 2006 at 16:01 Permalink - Edited 1st January 1970 at 01:00
Just like it couldnt do the COBRA about a year ago . Firebar i wasnt talking about limitations like what you mentioned , do IAF pilots routinly do kilbits in DACT ?? the limitations i was talking about were G load and AOA limiters which are placed during peacetime to preserve airframe life .
Regarding 360 degree instantanius back flips the word is still out , DOZER the demo pilot for the raptor said that he has seen most of flanker displays and that the raptor can pretty much the same with its TVC , and that they wont be displaying its full Airshow manueverability untill 2008 when they actually set out to a big air show the likes of Farnborough ( probably RIAT ) .
why ? Because it isnt designed by sukhoi???
How about combat pilot testimonials ( visit fencecheck codeone etc) where the COMBAT pilots ( not test pilots for crying out loud) have said that it is stall and departure free at all AOA just like the VISTA/MATV and X-31 and in COMBAT CODED RAPTOR it can sustain 60 degrees AOA .
Why do you say AOA for airshow only?? the raptor that performed those was FULLY OPERATIONAL IN AN OPERATIONAL SQUADRON , CAME OUT OF SQUADRON DUTY TO PERFORM THE SHOW AND PERFORMED IT WITH 8 MISSILES AND ENOUGH FUEL TO FLY TO AND FROM THE DESTINATION . THE PILOT HAS REPEATEDLY SAID THAT NO MODIFICATION WAS MADE TO THE JET!!!
ofcourse VISTA/MATV were not really F-16's now were they?? how could those aerodynamic configurations be usable at all AOA , perform cobras etc etc
No doubt that is why they are the standard evryone else tries to measure up to !!
Where did u not get the fact that the pilot has said that the F-22 has perfromed the COBRA in operational conditions with 8 missiles and a representative fuel load , and no special modifications were made ??
Why is it so hard for you to believe something that has been laid out so simple!!!
No it was 60 degrees max sustain , read the umpteen books on the ATF and Raptor !!
If you look hard enough you can see the tail codes quite clearly from this and other videos and the PILOT WHO FLEW THIS HAS MADE TESTIMONIALS REGARDING THE WEAPONRY WHICH HAVE BEEN POSTED IN THE VARIOUS THREADS , HE IS A MEMBER AT FENCECHECK AND VISITS THERE , HOWEVER HE VOULUNTARILY ASKED SOME OF HIS MATERIAL TO BE REMOVED BUT THE MATERIAL IS AVAILABLE HERE , HE HAS ALSO SAID IT IN A ARTICLE PUBLISHED AND POSTED BY ME - LOOK FOR IT AND YOU'LL SEE IT !!
i HAVE A list of things i want a raptor to do , but the raptor as a routine is only going to do what the demo pilot wants it to do period . personally i dont like DOZER's cobra ( the callsign of the pilot is dozer) , i prefer the snap on and snap off cobra of the flanker much better but dozer likes it slow and likes to wait just a tad bit ( mind you according to him he is still refining the cobra and it would be a lot different with time) to demonstrate that the noze doesnt snoop around and remains stable even at AOA of 120 degrees or so . I also want him to do a KILIBT and what not but too bad we dont have the right connections ;)
Posts: 9,683
By: sferrin - 28th September 2006 at 16:12 Permalink - Edited 1st January 1970 at 01:00
Firebar sees what he wants to see. Show him something that contradicts his beliefs and he tries to put a spin on it in a vain attempt to make it fit his own wishes. Frankly I think it's a waste of time even responding to him.
Posts: 12,109
By: bring_it_on - 28th September 2006 at 16:16 Permalink - Edited 1st January 1970 at 01:00
Read Airspacemag Aug-Sept 2006 issue article Raptor Rocks
I am posting some snippets from that article
Shower was joined at Oshkosh that day by Col. Thomas Bergeson, who entertained us with high-speed, excruciatingly loud passes in another Raptor while Shower flew off to collect his airplane for its next stunt. One of them he calls "the helicopter." The airplane is falling straight down, but rotating in a spin. This is one of Shower’s favorites—the guy must have a stomach made of titanium.
The jet can sustain over 30 degrees per second of yaw, he marvels. "Thirty degrees per second in an F-15? The beeper’s going off and I’m in an uncontrollable spin. But in an F-22, it’s totally controllable, and you’re just going ‘dit da dit da duh,’ " he hums. "And I’ll push the pedal the other way, and it will just stop and go 30 degrees in the opposite direction." Shower laughs in gleeful disbelief that an airplane will allow him to have this much fun.....
He’s seen demos and videos of performances by the Russian MiG 29 and Sukhoi Su 35, and admits that their maneuverability is probably on a par with the F-22. "I can do everything they can do and vice versa," he says. "We can all do some pretty neat stuff. But I love this part of it: That’s all they have. They don’t have the stealth , they don’t have the supercruise, they don’t have the integrated sensors, the avionics. We have an aircraft that does everything a fighter pilot has ever wanted to do. It has it all—you can tell by the price tag," he says, (about $137 million per copy, or $338 million if you count in all the Air Force's research costs).
For their performance, which started at 2:40 p.m., Shower and Bergeson took off from Langley, 800 miles away, at about 1:25. "We were going slow," Shower says. "We were only doing about .9 Mach. Over the continental United States, there’s only a couple of places we’re allowed to go supersonic so we don’t scare everybody. But we did the math and figured we could be there if we supercruised in about 25 or 30 minutes."
Please dont jump the gun and say that it can only sustain 30 degrees of AOA as he is talking about yaw rates!!
OTHER COMMENTS THAT HAVE BEEN MADE BY SHOWER (AKA DOZER)
Frazier can provide you the entire article so contact him!!!
Posts: 9,683
By: sferrin - 28th September 2006 at 16:24 Permalink - Edited 1st January 1970 at 01:00
No doubt this will start another debate/firestorm but. . . .
800 miles in 30 minutes would be 1600 mph
800 miles in 25 minutes would be 1920 mph
Posts: 12,109
By: bring_it_on - 28th September 2006 at 17:08 Permalink - Edited 1st January 1970 at 01:00
the 800 miles away was probably the distance on road and might not be the distance " as the crow flies " or it could be i just dont know and dont care to calculate .
Posts: 9,683
By: sferrin - 28th September 2006 at 23:42 Permalink - Edited 1st January 1970 at 01:00
According to Google Earth Langley AFB to Oshkosh WI is about 799 miles as the crow flies.
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By: JFrazier - 29th September 2006 at 01:56 Permalink - Edited 1st January 1970 at 01:00
Abosolutely ridiculous. Firebar, I concede defeat to your stupidity.
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By: SOC - 29th September 2006 at 04:17 Permalink - Edited 1st January 1970 at 01:00
If it's not beyond 90 degrees, it's not really a Cobra...
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By: aurcov - 29th September 2006 at 08:29 Permalink - Edited 1st January 1970 at 01:00
Whoud 120 deg qualify as a Cobra?
http://www.youtube.com/watch?v=yeczZtRLFZc&mode=related&search=
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By: SOC - 29th September 2006 at 08:38 Permalink - Edited 1st January 1970 at 01:00
Well duh, because it broke the 90-degree plane :D
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By: kilcoo316 - 29th September 2006 at 12:35 Permalink - Edited 1st January 1970 at 01:00
Just to answer a few comments in the thread [but I'm well hungover, so could get things a little muddled :D]
- Normally every aircraft has a flight envelope and a departure from controlled flight. However, new aircraft [such as the F-22 and OVT] have carefree handling as a design objective. Basically, this means the pilot can do what he wants in terms of flying the aircraft, and he will always retain a good measure of control authority over the aircraft. Therefore departure from controlled flight is impossible in an F-22 or OVT [or similar such aircraft].
- As far as I knew, the F-16 was AoA limited by lateral stability, its vertical fin induces problems in manouvering. A quick google found this: here. Its well worth a read.
- Also, fluidic TVC... From what I've read its still some way short of the efficiency of mechanical systems, and there are doubts as to whether the deficiencies can be overcome.
- Firebar is right in saying that manouverability is affected more by an aircraft's aerodynamics than its fly-by-wire capabilities. However, he is wrong in saying the F-22 has to have a limit to its AoA. There is no reason why it should.
I was gonna say more, but my head is killing me :o
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By: bring_it_on - 29th September 2006 at 12:42 Permalink - Edited 1st January 1970 at 01:00
The best way to get over a hangover is to never get to a point where you can get a hangover -
In other words , keep drinking!!!
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By: kilcoo316 - 29th September 2006 at 12:46 Permalink - Edited 1st January 1970 at 01:00
As much as i would enjoy that, I think my wallet might protest (again) :diablo:
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By: firebar - 29th September 2006 at 13:05 Permalink - Edited 1st January 1970 at 01:00
Doggy, you have to understand that F-16 is service limited to 26 degrees AoA because it was found that at about 30 degrees AoA it has strong propensity to departure from controlled flight. This often end in a flat spin.
This is aerodynamic characteristic of F-16s unstable configuration.
There is no FBW system which can correct this, and allow more AoA.
Regarding Tornado ADV, it is not unstable, but again, FBW controls can not substitute for a bad aerodynamics.
Every fighter has its AoA limit. Do not delude yourself.
That is max AoA from which it is possible to surely recover the aircraft without departure.
They have no problems at all. These are only fighters which have such high controllability at high AoA that they are able to demonstrate Tail slide and Cobra maneuvers before crowd in international airshows regularly.
Remember that american pilots say they are amazed with MiG-29s or SU-27s contlollability at high Alpha.
Do you understand that unstability has a bad influence on high AoA flights.
It is your wish.
Do you know that Russian fighters do a Super Cobra and Hook maneuvers, again on International Airshows. These are totaly out of the grasp of F-22.
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By: bring_it_on - 29th September 2006 at 13:26 Permalink - Edited 1st January 1970 at 01:00
You say that the Su-30++ and Mig-29++ are controlable at any AOA yet in your previous post you say this -
So whats the AOA limit of a su-30MKI , F-16MATV or a Mig-35 ?? at what AOA do they become Uncontrolable ??
There is videographic evidence to show RAPTOR doing TAIL side and COBRA and the WI show had some intrenational exibhitors i believe like HONDA . However if you want high end trade shows the likes of which dont really exist in the US ( big three or 4 like farnbr. , paris , RIAT etc ) then you'd have to wait about 14 months or so before the F-22 goes to one of them according to the demonstration pilot ( Shower)
Again do the russian aircraft hold cobras in a sustained manner ?? Are you sugesting that the Super flanker can sustain 120+ degree AOA ??
The pilot demonstrating these manuevrs and who also happens to be the most experienced in service raptor pilot says that he can perform everyone of those manuevers and with time he will do so leading up to the big airshow demos more likely in 2008 - however do except some more snippets at Langley this year . Now we can either believe you or believe the man who flies this jet on a daily basis and is asking every entusiast to just hold a while .
The choices i am sorry to inform you have allready been made by most members!!!
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By: firebar - 29th September 2006 at 13:34 Permalink - Edited 1st January 1970 at 01:00
All right, but ask Israeli pilots which, in F-15s, took part in simulated combat with Luftwaffe Mig-29 in Sardinia, how they fared ?
Note that it was downgraded Mig-29 with tuned down engines.
Regarding service limitations of AoA, this is not imposed as a measure to preserve airframe life.
Every fighter has its own AoA limit, beyond which it is prone to departure.
Look at, for instance, F-18 manual. It says that beyound 50 to 55 degrees AoA, the clean F-18 will surely depart and will end in a Falling Leaf from which escape is almost impossible.
There is no such constraints for Mig-29 or SU-27.
I would say that it is not safe for F-22 yet to demonstrate Cobra maneuver in International airshows. To do it, the fighter has to be absolutely safe from departure. It is not easy to acomplish at 90 degrees AoA.
I believe it. But this is not enough. The pilot has to be able to repeat this maneuver every time without fear that his aircraft will depart.
Only then it will be ready for International Airshows.
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By: firebar - 29th September 2006 at 13:47 Permalink - Edited 1st January 1970 at 01:00
I do not doubt this. I only say that MiG-29 and SU-27 do that maneuvers absolutely confidently in International Airshows, which F-22 can not duplicate yet.
Of course, it is TVC aircraft and when fine tuned, it is going to do it also.