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  • chanjyj
    replied
    I have a bit of trouble understanding the question. Are you looking for details about their mission scope, their technical build, how they came about (development process)..

    Leave a comment:


  • doppelganger
    replied
    I love old planes. Actually I love WWII planes, not the biplanes and stuff.

    Expecially love the Spitfire. Used to sketch them from comics as a kid.

    Now I have been following them on Discovery Science. Also the Discovery Turbo stuff on the Reno races where the highly souped up Mustangs are boss.

    From what I understand, the Spitfire and the Mustang share the same Rolls Royce Merlin engine. But the Spitfire is called a sports car and ballet dancer rolled into one, while the Mustang had better armor and longer range.

    I would love to read something about both of these which I can understand as a lay person. Can someone please help? Chogy?

    Leave a comment:


  • Chogy
    replied
    Originally posted by Stitch View Post
    Chogy - I'm guessing that part of the reason for this is that the F-15 was probably TOO responsive to control inputs; low wing-loading on the Eagle was probably counter-productive to AAR. I'm assuming something like an F-104 was better at AAR because of the lower responsonsiveness to control inputs.
    I think it also has to do with the engines. The transition from straight turbojets to fan jets with bypass causes the engines to be a little less responsive to minute tweaks, which are critical for good formation flying. It doesn't mean it's hard or can't be done, but it's definitely noticeable. This makes the formation flying needed just a tiny bit sloppier. And you are correct, the wing loading makes it more susceptible to normal wake turbulence and bumps. The F-4, T-38, are like lead sleds; they track very true and firm. More modern jets bounce about a but more.

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  • jrb1537
    replied
    Originally posted by Stitch View Post
    Chogy - I'm guessing that part of the reason for this is that the F-15 was probably TOO responsive to control inputs; low wing-loading on the Eagle was probably counter-productive to AAR. I'm assuming something like an F-104 was better at AAR because of the lower responsonsiveness to control inputs.
    Strangely, though, the F-104 used probe and drogue, not boom type.

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  • Stitch
    replied
    Originally posted by Chogy View Post
    The Eagle was hard to refuel compared to others, because the receptacle was both behind and offset to one side. The boom telescopes, and there are color bands where the two sections mate; green, yellow, and red IIRC. We had to use the rear-view mirror to keep track of the boom, and while the guidance lights on the tanker are helpful, it was boom telescope and general position relative to the tanker that most guys used to stay in position.
    Chogy - I'm guessing that part of the reason for this is that the F-15 was probably TOO responsive to control inputs; low wing-loading on the Eagle was probably counter-productive to AAR. I'm assuming something like an F-104 was better at AAR because of the lower responsonsiveness to control inputs.

    Leave a comment:


  • Chogy
    replied
    AAR is one of those things that looks easier than it really is. It requires some very precise flying by the recipient. And it is common, especially for a noob, to fall off the boom. If you exceed certain parameters, the boom operator will release you. Much mockery and laughter ensues, and not only are you shamed before your comrades as being weak, you'll normally buy the beer that evening.

    The Eagle was hard to refuel compared to others, because the receptacle was both behind and offset to one side. The boom telescopes, and there are color bands where the two sections mate; green, yellow, and red IIRC. We had to use the rear-view mirror to keep track of the boom, and while the guidance lights on the tanker are helpful, it was boom telescope and general position relative to the tanker that most guys used to stay in position.

    The "night 4-ship flight lead AAR" mission was one of the hardest boxes you had to check off enroute to being certified as a 4-ship lead.

    Interesting trivia - the USAF went with the boom system decades ago, vs. the drogue/basket setup of the Navy. The latter was supposed to be easier, but since I never tried it, I cannot confirm that. But the reason for this choice was simple - the boom system's flow rate was much greater than the Navy variant, and this was necessary to refuel the B-52 in any sort of reasonable time period. Since the U.S. Navy did not operate massive aircraft, the drogue system was acceptable, and also more flexible in use, being able to refuel helicopters, and also refueling units could be added to other aircraft as a store, allowing buddy refueling.

    Leave a comment:


  • Phoenix10
    replied
    Originally posted by Gun Boat View Post
    The question is (as stupid as it may sound):

    When an aircraft connects with the refuelling probe of a tanker does the pilot of the aircraft being refuelled surrender control to the tanker?

    I think it doesn't but we just broke out the old atari game 'Topgun' and once you connect you surrender control. My mates reckon this is how it works in real life.
    I have sworn black and blue that it isn't even possible and informed them that I know a place where we can find out. Chogy, please say it ain't so!

    Thanks in advance.
    No control is surrendered. The pilot of the receiving aircraft remains in complete control of his aircraft. On tankers with a boom (as apposed to probe and drogue), there is actually a boom operator that "flies the boom" and directs the receiver pilot. The pilot of the receiving aircraft has to try to say in an imaginary box behind and below the tanker. For example, there are Pilot Director Lights on the bottom of the KC-135 that the boom operator uses to give visual commands (move left, move right, break away, etc) to the pilot. If the receiver pilot is in the right area, the boom operator can fly the boom and physically mate it with the receiving aircraft. Once they are connected, the boom operate can still give commands to the receiver pilot to make sure he/she stays in the right spot. The connection is not so strong that the receiving aircraft could go hands off the stick and be "towed" along by the tanker or anything like that. There is not currently a production system that would allow the receiving aircraft to be controlled by the tanker such that the pilot can go hands off. Although, there is a lot of research into autonomous aerial refueling for UAVs that could change that if the technology were to be advanced, fielded, then adapted to manned aircraft. I worked on one such project.
    Last edited by Phoenix10; 20 Apr 13,, 17:30.

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  • Gun Boat
    replied
    The question is (as stupid as it may sound):

    When an aircraft connects with the refuelling probe of a tanker does the pilot of the aircraft being refuelled surrender control to the tanker?

    I think it doesn't but we just broke out the old atari game 'Topgun' and once you connect you surrender control. My mates reckon this is how it works in real life.
    I have sworn black and blue that it isn't even possible and informed them that I know a place where we can find out. Chogy, please say it ain't so!

    Thanks in advance.

    Leave a comment:


  • mako88sb
    replied
    Originally posted by Chogy View Post
    Mako, I'm just guessing... It was a different era, different mentality, and they may very well have done that exercise as described. But Yeager's claims of visual acuity - no sir.

    You may be interested in the little-known fact that one Mr. George Welch very likely exceeded mach 1 in the XP-86 before Yeager's X-1 flight. The profile Welch flew in the test F-86 Sabre that day was proven later to exceed mach 1 with ease; a sonic boom was heard, and Welch's description of the flight indicated that he busted the sound barrier.

    The Germans could have EASILY broken mach 1 with a manned craft during WW2. Not the Me-262 or the comet rocket plane... the V2 missile. While they didn't actually do it - they were too busy lobbing bombs at England - the V2 payload of TNT could have easily been replaced with a small man-carrying capsule for a hypersonic, suborbital ride that would have shattered a number of manned aviation records. First suborbital space flight, first supersonic man, etc.

    Mach Match | History of Flight | Air & Space Magazine

    Some people claim "No fair, Welch did it in a dive!" That's not the point. Dive or not, the record/feat was "first supersonic man."

    IIRC the fastest MEN of all time was one of the Apollo missions, Apollo 10 I believe. Their re-entry was a bit off and their velocity was extreme, beating all other manned space flights before or since.
    Thanks for the link. Very interesting reading. So not only did he accomplish it 2 weeks prior on the XP-86's first flight but he did it again 20 mins before Yeager's historic flight. Pretty amazing guy! Checking him out on the internet I was surprised to see he was heir to the grape juice fortune. Also found out he was one of the 2 pilots that drove out to Haleiwa Field as portrayed in Tora! Tora! Tora! and shot down 4 Japanese aircraft. Should of won the Medal of Honor but it was denied because he took off without proper authorization?!?!??? That's crazy! What the hell where they thinking?

    I always had suspicions that Yeager wasn't above embellishing stories about himself and Neil Armstrong's auto-biography just confirmed it for me.
    Last edited by mako88sb; 13 Aug 12,, 15:43.

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  • Chogy
    replied
    Mako, I'm just guessing... It was a different era, different mentality, and they may very well have done that exercise as described. But Yeager's claims of visual acuity - no sir.

    You may be interested in the little-known fact that one Mr. George Welch very likely exceeded mach 1 in the XP-86 before Yeager's X-1 flight. The profile Welch flew in the test F-86 Sabre that day was proven later to exceed mach 1 with ease; a sonic boom was heard, and Welch's description of the flight indicated that he busted the sound barrier.

    The Germans could have EASILY broken mach 1 with a manned craft during WW2. Not the Me-262 or the comet rocket plane... the V2 missile. While they didn't actually do it - they were too busy lobbing bombs at England - the V2 payload of TNT could have easily been replaced with a small man-carrying capsule for a hypersonic, suborbital ride that would have shattered a number of manned aviation records. First suborbital space flight, first supersonic man, etc.

    http://www.airspacemag.com/history-of-flight/mach.html

    Some people claim "No fair, Welch did it in a dive!" That's not the point. Dive or not, the record/feat was "first supersonic man."

    IIRC the fastest MEN of all time was one of the Apollo missions, Apollo 10 I believe. Their re-entry was a bit off and their velocity was extreme, beating all other manned space flights before or since.
    Last edited by Chogy; 12 Aug 12,, 17:08.

    Leave a comment:


  • zraver
    replied
    Originally posted by Chogy View Post
    I suspect you're not going to get a verification of this one. I'm having trouble understanding the utility of such a feat. Obviously, cardinal direction, but if the sun is anywhere off 12:00 noon, the sun is a better indicator of rough cardinal direction within +/- 30 degrees.

    Standing on the ground and locating a star with naked eyes just might be done on a perfect day, but I have my doubts. Put that same set of eyes in a rumbling, vibrating cockpit and viewing through glass or perspex, and I have to say it is simply not possible.

    Besides, airplanes then all had whiskey compasses at a minimum. And the wet compass was an unpowered device that, barring taking a bullet, simply doesn't fail. It doesn't seem logical that they'd waste their time with such a feat unless the sole purpose was to find men with near superhuman eyesight.
    IJNAJ scout bombers, likely it was a skill practiced in early or late hours when the sun was well down on the horizon and done mostly by navigators with the canopy slid back. With the sun low and a few key stellar bench marks you can probably navigate.

    With long over water flights on a single engine every possible form of navigational backup makes sense from that perspective. US and British navigators were trained in celestial navigation

    Leave a comment:


  • mako88sb
    replied
    Originally posted by Chogy View Post
    A qualified "maybe." Obviously in the days of primitive or non-existent radar or GCI, visual acuity is extremely important. I remember reading somewhere that Chuck Yeager claimed to be able to see German fighters at 40 to 50 nautical miles. I say pure B.S. In my entire career, I never met a single individual who could see a fighter-sized airplane with the naked eye outside of 15 to 20 NM, with the sole exception of sun glints or contrails.

    There's an easy way to confirm it. Look outside when airliners are passing overhead in cruise. Those HUGE jets are at 6 to 7 NM altitude, no more. They are tiny, tiny specks, and visible normally only because they con. Replace the 767 with a tiny Focke-Wulf, and no con. Excellent eyes might see them at 10NM. Superb eyes at 15. Maybe.

    Again, there's a big difference between standing still on the ground, vs a rumbling, hot cockpit encased in primitive perspex.

    A better way to train for visual acuity would be to have two flights orbit known geographical features a fixed distance apart, and let the pilots of both flights practice their visual lookout. Then, have one flight proceed to the other point, practicing the lookout the whole way, while the other attacks.

    Exercising a proper and effective visual lookout is actually a lot of work. It's very easy to get lazy, and that's how you get killed in a visual environment.

    Thanks Chogy. I read Yeager's book and remember him mentioning that as well as spotting a burning tanker below 10 mins before the rest of his flight could. Then there was the bit where Neil Armstrong refused to listen to him about not doing a touch and go at Smith Ranch Dry Lake and they ended up stuck. I read "First Man" not too long ago and Armstrong says there wasn't a word from Yeager about not giving it a try and even encouraged him to make a second attempt that was the one that actually bogged them down.

    The way you mention for training certainly makes sense but I think the star looking method that Saburo talks about in his book was before they even got any actual flying experience. It's been awhile since I've read it though so maybe I'm wrong about that.

    I guess I could try to verify it myself by trying to spot some of the brighter magnitude stars with binos and an astronomy program like Stellarium to guide me.

    Leave a comment:


  • Chogy
    replied
    Originally posted by mako88sb View Post
    I always thought the intent was to train the prospective pilots on improving their ability to locate enemy aircraft from a further distance then what they normally would be capable of. Does this not seem like a reasonable outcome of such a skill?
    A qualified "maybe." Obviously in the days of primitive or non-existent radar or GCI, visual acuity is extremely important. I remember reading somewhere that Chuck Yeager claimed to be able to see German fighters at 40 to 50 nautical miles. I say pure B.S. In my entire career, I never met a single individual who could see a fighter-sized airplane with the naked eye outside of 15 to 20 NM, with the sole exception of sun glints or contrails.

    There's an easy way to confirm it. Look outside when airliners are passing overhead in cruise. Those HUGE jets are at 6 to 7 NM altitude, no more. They are tiny, tiny specks, and visible normally only because they con. Replace the 767 with a tiny Focke-Wulf, and no con. Excellent eyes might see them at 10NM. Superb eyes at 15. Maybe.

    Again, there's a big difference between standing still on the ground, vs a rumbling, hot cockpit encased in primitive perspex.

    A better way to train for visual acuity would be to have two flights orbit known geographical features a fixed distance apart, and let the pilots of both flights practice their visual lookout. Then, have one flight proceed to the other point, practicing the lookout the whole way, while the other attacks.

    Exercising a proper and effective visual lookout is actually a lot of work. It's very easy to get lazy, and that's how you get killed in a visual environment.

    Leave a comment:


  • mako88sb
    replied
    Originally posted by Chogy View Post
    I suspect you're not going to get a verification of this one. I'm having trouble understanding the utility of such a feat. Obviously, cardinal direction, but if the sun is anywhere off 12:00 noon, the sun is a better indicator of rough cardinal direction within +/- 30 degrees.

    Standing on the ground and locating a star with naked eyes just might be done on a perfect day, but I have my doubts. Put that same set of eyes in a rumbling, vibrating cockpit and viewing through glass or perspex, and I have to say it is simply not possible.

    Besides, airplanes then all had whiskey compasses at a minimum. And the wet compass was an unpowered device that, barring taking a bullet, simply doesn't fail. It doesn't seem logical that they'd waste their time with such a feat unless the sole purpose was to find men with near superhuman eyesight.

    I always thought the intent was to train the prospective pilots on improving their ability to locate enemy aircraft from a further distance then what they normally would be capable of. Does this not seem like a reasonable outcome of such a skill?

    Leave a comment:


  • Chogy
    replied
    I suspect you're not going to get a verification of this one. I'm having trouble understanding the utility of such a feat. Obviously, cardinal direction, but if the sun is anywhere off 12:00 noon, the sun is a better indicator of rough cardinal direction within +/- 30 degrees.

    Standing on the ground and locating a star with naked eyes just might be done on a perfect day, but I have my doubts. Put that same set of eyes in a rumbling, vibrating cockpit and viewing through glass or perspex, and I have to say it is simply not possible.

    Besides, airplanes then all had whiskey compasses at a minimum. And the wet compass was an unpowered device that, barring taking a bullet, simply doesn't fail. It doesn't seem logical that they'd waste their time with such a feat unless the sole purpose was to find men with near superhuman eyesight.

    Leave a comment:

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