"There is never enough time to do or say all the things that we would wish. The thing is to try to do as much as you can in the time that you have. Remember Scrooge, time is short, and suddenly, you're not there any more." -Ghost of Christmas Present, Scrooge
Drag comes from two sources, parasite (stuff in the slipstream) and induced. Induced is drag associated with the simple act of obtaining lift. When you pull G, you are asking for more lift, and induced drag goes up as well. So when you aileron roll, you increase parasite drag due to control throw movement and the slight yaw around the long axis, but you reduce the induced drag. So it's a bit of a wash.
A barrel roll could be called an aileron roll at 1 constant G, and is a harder maneuver to do well. It forms a corkscrew flight path through the sky, rather than the jet continuing straight and simply rolling about the long axis.
HTH and makes some sense!
reading it many times sure helps!
more questions :
will a pilot throttle engine power up and down a lot in combat/maneuvering? or will he simply set throttle up to the 'healthy' maximum/military thrust and make the best use of it? how about the use of ABs?
Chogy sir, what is your favorite fighter
Last edited by paintgun; 12 Oct 11, at 23:43.
In the days before the F-14 on up, the throttle was pretty much parked at the stops until the very end of the maneuvering fight, when throttle modulation might be necessary to prevent an overshoot, and settle into a stable gun track. Despite this, not only would they not accelerate, the'd both decelerate AND lose altitude, due to the high G and demands on the airplane to turn, turn, turn some more. With more modern fighters, the initial portions were pretty much locked in A/B, but modulation within A/B and below become more common. It all depended upon the myriad of factors the attacker or defender sees... range, angle off, closure. Sometimes you'd WANT to bleed airspeed very quickly, and you'd need idle to do this best, but even in a slow-speed fight, the throttle generally gets fed back in; otherwise, you're heading downhill quickly despite the slow airspeed and nose-high flight profile.will a pilot throttle engine power up and down a lot in combat/maneuvering? or will he simply set throttle up to the 'healthy' maximum/military thrust and make the best use of it? how about the use of ABs?
Think of the Hornet's ultra high AOA and slow-speed pass at an airshow. He is doing a hundred knots, plowing through the sky, AOA (angle of attack) very high, but to do this, he is in A/B and he is not accelerating. The drag on the airplane is enormous. To accelerate once more, he must break the AOA (lower the nose) to reduce drag.
In a nutshell, you're at MAX for maybe 50% of the time, modulated within the A/B region for 25%, and at mil or below maybe 25%. There's no such thing as too much thrust. It is amazing how quickly and easily one could go from 25,000' and mach 1 to sea level and 200 knots.
Not surprising given that at 40,000 pounds weight, at 7 G, the jet really "weighs" 280,000 pounds, the wing loading is through the roof, and you are asking 50,000 pounds of thrust to fly the 280,000 pound airplane.
That's like asking a sports car guy what his favorite car is. He's going to name the car he drives. I flew the F-15, it took care of me and I loved it dearly. The F-16 guy will love his F-16. It's human nature.Chogy sir, what is your favorite fighter
There is no such thing as an ex-fighter pilot. Once a young man straps on a jet aircraft and climbs into the heavens to do battle, it sears his psyche forever. At some point he will hang up his flight suit - eventually they all do - and in the autumn of his years his eyes may dim and he may be stooped with age. But ask him about his life, and his eyes flash and his back straightens and his hands demonstrate aerial maneuvers and every conversation begins with "There I was at..." and he is young again. He remembers the days when he sky-danced through the heavens, when he could press a button and summon the lightning and invoke the thunder, the days when he was a prince of the earth and a lord of the heavens. He remembers his glory days and he is young again.
Robert Coram, "Boyd"
One other problem not anticipated by the engine folk was how often the engine would be "snatched" from one stop to the other at AOA and altitude extremes. This caused compressor stalling and other (worse) things. In the early 1970's, fuel controllers, that monitored throttle demands, were hydromechanical machines... like a WW2 carburetor + turbo-supercharging that could sense the basics of the world outside and the demands of the pilot, and schedule fuel.
These worked OK. But like so much else, the advances in digital electronics paid huge dividends. Around maybe 1985, the DEEC (digital electronic engine control) was added to the F-100 engine, and the engine's behaviors were greatly improved. It allowed full throttle movement in all phases of flight. The DEEC also gave superior acceleration of the engine, and it was so pronounced that one could make excuses in the debrief... "Well I didn't have a DEEC airplane, which is why I lost the rolling scissors..." That sort of thing.
nice quote.There is no such thing as an ex-fighter pilot. Once a young man straps on a jet aircraft and climbs into the heavens to do battle, it sears his psyche forever. At some point he will hang up his flight suit - eventually they all do - and in the autumn of his years his eyes may dim and he may be stooped with age. But ask him about his life, and his eyes flash and his back straightens and his hands demonstrate aerial maneuvers and every conversation begins with "There I was at..." and he is young again. He remembers the days when he sky-danced through the heavens, when he could press a button and summon the lightning and invoke the thunder, the days when he was a prince of the earth and a lord of the heavens. He remembers his glory days and he is young again.
Robert Coram, "Boyd"
we used to have a "Fighter Bar" prior to our move back to the Pentagon, and posted above the Bar was a sign that said:
"ALL STORIES FROM OPERATIONAL LIFE ONLY. NO 'THERE I WAS, TYPING A STAFF SUMMARY SHEET...' "
There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that "My ignorance is just as good as your knowledge."- Isaac Asimov
The Coram quote leaped out at me when I read his book about Boyd. I'm not quite stooped yet, but I'm out of the game!
The thing with the hands... it's SO real. Pilots do it unconsciously because a pair of hands is the quickest (maybe the only) way to get across two 3-dimensional flight paths to another person quickly and easily. At squadron parties with wives and such, it was inevitable, and the wives' eyes would roll back into their heads whenever it happened. In briefing rooms, we had two model airplanes on sticks, and they were used extensively to teach. They were invaluable.
I wonder if squadrons even have their own bars any more. The official O'club people hated them because they took away business. We loved them. As soon as the last flight stepped, the bar was open, and we'd often debrief with a cold pitcher of beer.
I have a question in regards to this Mayday episode I seen a couple years ago about China Airlines Flight 006:
Panic Over The Pacific Part 1 - Air Crash Investigation/Mayday - YouTube
Seems incredible that the stresses involved would actually rip the main gear doors off and do damage to the tail-plane yet somehow it was able to safely land. What an amazing plane! Near the end of part 5, they mention that it was put through "maneuvers and stresses that far outweighed it's known limits". It was repaired and put back into service. What I'm wondering is what kind of testing and airframe checks would they have to be done to be able to certify it for passenger use? It would seem to me that considering what this plane went through, that they may of had to come up with new procedures to make absolutely certain it was safe to fly again.
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