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#11
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On Fri, 04 Jul 2003 15:44:19 GMT, "Gord Beaman" )
wrote: (Peter Stickney) wrote: Radiop Research, in Waterbury CT, has complete units listed in the Thomas Register. And all sort of other neat toys. I'm saving up for the MD-5 system (B-52 tail turret, including tboth th eradars and the turret) myself. But not the twenties Pete?...you disappoints me... (picturing your turret mounted on your pickup truck with a B & W just slashing in 10 feet behind you with lights and sirens blaring and these twin 20's swinging around and depressing to point right into his windscreen !!!... HooWee!...) Might explain why his local police preordered the new "stealth" model police cruisers. |
#12
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In article ,
Blair Maynard writes: On Fri, 04 Jul 2003 15:44:19 GMT, "Gord Beaman" ) wrote: (Peter Stickney) wrote: Radiop Research, in Waterbury CT, has complete units listed in the Thomas Register. And all sort of other neat toys. I'm saving up for the MD-5 system (B-52 tail turret, including tboth th eradars and the turret) myself. But not the twenties Pete?...you disappoints me... You just wouldn't believe the paperwork involved. A .50 cal can be done, but anything over that, and you enter Destructive Device territory. Think of it as teh difference between a Secret and a Top Secret Clearance. (picturing your turret mounted on your pickup truck with a B & W just slashing in 10 feet behind you with lights and sirens blaring and these twin 20's swinging around and depressing to point right into his windscreen !!!... HooWee!...) Nah, we're all friendly folks down here. The big car chases only happen in the movies. For that matter, they never gave me any flak about the tanks - or when we registered an M20 Armored Scout Vehicle as a 1943 Ford Convertable. I woldn't mind one of those 1&1/2 ton Chevys with the Martin turret that they used for gunnery training, though. with a lead-computing gunsight and a pair of autofeeding 12-Gauges I might actually hit one of those danged ducks. (Spent years shivering in the swamps - the only duck I get I hit with the truck on the way home. He was executing a missed approach while overgrossed & couldn't climb out of the way) Might explain why his local police preordered the new "stealth" model police cruisers. Actually, I had the Chief LEO come by a couple of years back wanting me to broker a deal for some Armo[u]red Cars. (Money to use, and nifty toys, basically). I was able to talk him out of it, though by pointing out that he'd never be able to afford the supporting infantry he'd need to go with them. They were much better off spending teh dough on communications gear. -- Pete Stickney A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster |
#13
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"Peter Stickney" wrote in message
In article , Blair Maynard writes: On Fri, 04 Jul 2003 15:44:19 GMT, "Gord Beaman" ) wrote: (Peter Stickney) wrote: Radiop Research, in Waterbury CT, has complete units listed in the Thomas Register. And all sort of other neat toys. I'm saving up for the MD-5 system (B-52 tail turret, including tboth th eradars and the turret) myself. But not the twenties Pete?...you disappoints me... You just wouldn't believe the paperwork involved. A .50 cal can be done, but anything over that, and you enter Destructive Device territory. Think of it as teh difference between a Secret and a Top Secret Clearance. (picturing your turret mounted on your pickup truck with a B & W just slashing in 10 feet behind you with lights and sirens blaring and these twin 20's swinging around and depressing to point right into his windscreen !!!... HooWee!...) Nah, we're all friendly folks down here. The big car chases only happen in the movies. For that matter, they never gave me any flak about the tanks - or when we registered an M20 Armored Scout Vehicle as a 1943 Ford Convertable. You could get a flatbed deuce-and-a-half and do a Guntruck-workup ala the US Army in Vietnam. Some of those SOB's had 7.62 miniguns! -- http://www.delversdungeon.dragonsfoot.org Remove the X's in my email address to respond. "Damn you Silvey, and your endless fortunes." - Stephen Weir I hate furries. |
#14
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#15
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According to something I saw on the History Channel yesterday,
the F-86 had an all-flying tail (though they used another term) first developed for the X-1 (called XS-1). It enabled pitch control in the transonic region, without which supersonic flight could not have been achieved, and it made the F-86 a much better dogfighting aircraft at transonic speeds. Did the Soviets learn about the all-flying tail from the captured F-86, and put it on their later fighters ------------------------------------------ Stephen Harding ) wrote: : "Smithsonian Air and Space" has an interesting article describing Soviet : attempts to get their hands on an F-86 during the Korean War. : A first plan was developed to use specially trained pilots of MiG-15s to : actually box in a candidate F-86 and force him down at a Communist base. : The Russian CO of the Soviet AF unit actually fighting in Korea (USAF pilots : had come to suspect they were fighting Russians rather than NKs or Chinese : but there was still nothing official known about their presence), thought : the plan idiocy, and this was proven with the gradual shoot down of many : in the unit attempting to corral a Saber. : But an F-86A eventually went down and was hauled off, barely making an : escape from an attacking B-26. The aircraft was tested and quite a few : features found their way into MiG-15 and 17. : One of the most useful knowledge gains was with the radar controlled gunsight : used on the F-86. Very accurate and helping tilt the balance of light : weaponry of the F-86 (6 .50 MG) against the MiG (37 and 23mm cannon). : The Soviets developed a reciever that listened specifically for the wavelength : of the gunsight radar, thus giving the Soviet pilot some warning of : approaching USAF Sabers. It was prone to give false readings, but was an : overall invaluable feature. The life of its developer was probably saved : by its success since he had the misfortune of being "politically incorrect" : enough to be "denounced" at a time when it meant the Gulag or worse. : This electronic device is standard part of any modern fighter aircraft : indicating "radar lock" from targeting AAA/missiles. : SMH |
#16
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In article ,
Guy Alcala writes: Emmanuel Gustin wrote: "Merlin Dorfman" wrote in message ... Did the Soviets learn about the all-flying tail from the captured F-86, and put it on their later fighters The F-86A did not have the flying tail, this feature was introduced by the F-86E. This model entered combat in Korea in September 1951. The first Soviet fighter with the flying tail appears to have been the SM-9/2 prototype of the MiG-19, which was built in 1954. So it is quite likely that the Soviets were aware of the use of a slab tailplane on the F-86E when they designed the SM-9/2. On the other hand, NASA's adoption of the 'flying tail' appears to have been inspired by British data. There's a common misconception here. The "all-flying tail" on the F-86E and F wasn't a slab, it was a movable stabilizer with separate (but linked) elevator, as developed for the XS-1 (and credited by Yeager with allowing the a/c to be controllable through the Mach). The slab came in on the F-100, IIRR. From what I recall, there'd come a Mach number when the shock wave from compressibility would make the elevator ineffective (usually leading to tuck under), but the stabilizer itself would then be forward of the shock and retain its effectiveness. So the stabilizer was made movable (i.e. trimmable like a Buff, but directly connected to the joystick instead of just the trim switch) and linked to the elevator around a center pivot. The two surfaces were geared to move in a certain relationship to each other. I don't know the specific details (whether it was based on IMN or just a pure mechanical relationship). Hopefully Mary, Pete or someone else can fill in the details. F-86D/Ls and Hs had a one-piece slab. The reason for th all-moving tails (dangit, no chalkboard again! Assume a chalkboard, and a lot of Fighter-Pilot hand talking) Think of the stabilizer/elevator combination as a wing (Wich, after all, it is) At subsonic speeds, deflecting the elevator affects the airflow over the entire surface, so that the entire are of the stabilizer is used to control pitch. As the flow over the stabilizer gets transonic, and the shockwaves form, elevator deflection begins t only effect the flow over the elevators themselves, greatly reducing effectiveness. The solution is to move the entire stab (stabilator), which lets the entire surface develop whatever lift needs to be created to counterbalance the wing. (It's early yat - I've only had 1 cuppa Coffee) Why doesn't every airplane use this? (The Wright Brothers did) The problem is that once the stabilizer had to get above a certain small size, it's danged hard to move manually, no matter how much you balance it. It took the advent of powered controls, (The electric screw jack on the XS-1, or the hydraulics on the F-86E) to make it practical. You can certainly fly a transonic or supersonic airplane without using a slab, but what happens is that your pitch authority (Ability to raise or lower the nose) decreases, and, depending on the configuration, teh airplane may not be able to be trimmed at all. (The pitchup of the F-84s, for example.) -- Pete Stickney A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster |
#17
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Peter Stickney ) wrote:
.... : You can certainly fly a transonic or supersonic airplane without using : a slab, but what happens is that your pitch authority (Ability to : raise or lower the nose) decreases, and, depending on the : configuration, teh airplane may not be able to be trimmed at all. : (The pitchup of the F-84s, for example.) Is this the "control reversal" at transonic speed mentioned in the British film, "Breaking the Sound Barrier?" (I know that opinions vary as to whether or not control reversal is real.) |
#18
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"ian maclure" wrote:
In article , "Merlin Dorfman" wrote: Peter Stickney ) wrote: ... : You can certainly fly a transonic or supersonic airplane without using : a slab, but what happens is that your pitch authority (Ability to : raise or lower the nose) decreases, and, depending on the : configuration, teh airplane may not be able to be trimmed at all. : (The pitchup of the F-84s, for example.) Is this the "control reversal" at transonic speed mentioned in the British film, "Breaking the Sound Barrier?" (I know that opinions vary as to whether or not control reversal is real.) Control reversal is a real aeroelastic effect. Nothing mythical about it. Basically moving the control surface bends the airfoil which overpowers whatever effect the movibale control surface was supposed to provide. IBM But why wouldn't this merely reduce any intended effect?...IOW you want 'that wing' up, you put 'that aileron' down but the slipstream is so strong that the aileron moves only half as far as you commanded and the wing flexes the opposite way to make up the difference?...I think it has to do with the shock 'spike' which moves erratically with small changes in transonic speeds and this provides the actual reversal. -- -Gord. |
#19
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In article ,
Merlin Dorfman writes: Peter Stickney ) wrote: ... : You can certainly fly a transonic or supersonic airplane without using : a slab, but what happens is that your pitch authority (Ability to : raise or lower the nose) decreases, and, depending on the : configuration, teh airplane may not be able to be trimmed at all. : (The pitchup of the F-84s, for example.) Is this the "control reversal" at transonic speed mentioned in the British film, "Breaking the Sound Barrier?" (I know that opinions vary as to whether or not control reversal is real.) Well, the movie's a movie, and then, well, there's reality. In the early days of flight into the transonic reagion, airplanes would display all manner of behavior. Some would pitch down, (Meteor) SOme would pitch up (F-84) Some would pitch down & then pitch up (Canberra, IIRC), some would porpoise divergently, eventually risking breaking up (Vampire), and soem would just keep right on going with the pilot more passenger than director. (Venom). I suppose it would be possible for an airplane to pitch up and then pitch down, but usually the pitchup was so severe that it bled off a lot of speed, and bent the airplane. This was due to the various shifts of the Center of Moment of the airfoil as shockwaves began to form and move along the wing and tail surfaces. What gets felt in the cockpit is the change in trim force as this happens, and the perceived feel of what's going on. For ecample, you're hauling back in the stick, with nothing happening, and then the airplane pitches up to the extent that holding the stick in place feels like you're pushing it. Elevators don't work backwards, or anything like that. It was possible to get situations where aileron deflection at high speeds would bend the wing in the opposite direction, reducing and eventually reversing roll control. B-47s were quite prone to this, which led to the redline limit of 425 kts IAS. F-86s were somewhat subject to it, and some of the thinner winged transonic fighters like the FJ-4 Fury and F3H Demon could, it hey had a tendency to roll a bit be "fixed" by slamming the stick hard over at high IAS, bending the wings into rig. (Sort of like warping the wingtip of a balsa glider to make it fly straight) This concern about bending the wings is what led to the inboard ailerons of the F-100 and F-8 Crusader. Nowadays, (Post 1955 or so), we seem to have a handle on it, and passing through the transonic range is a bit dull. All you notice is a bit of change in the trim feel on some airplanes, the ASI jumps, and the fuel goes away fast. If you get a chance, go check out the NACA Technical Reports Server, for teh period between 1943 and 1953. There's a lot of stuff in there on the transonic behavior of a lot of airplanes, ranging from dive tests of a glider P-51 to the pitchup tendencies of various swept-wing jets. Most of it is, well, technical, (saves changing the name), but the abstracts can be rather clear. -- Pete Stickney A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster |
#20
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