warchild
Charter Member
Even if i didnt know the hell this plane would put its pilots through, i'd be afraid too..
NACA pilot Joseph A. Walker made his pilot checkout flight in the X-3 on August 23, 1954, then conducting eight research flights in September and October. By late October, the research program was expanded to include lateral and directional stability tests. In these tests, the X-3 was abruptly rolled at transonic and supersonic speeds, with the rudder kept centered. Despite its shortcomings, the X-3 was ideal for these tests. The mass of its engines, fuel and structure was concentrated in its long, narrow fuselage, while its wings were short and stubby. As a result, the X-3 was "loaded" along its fuselage, rather than its wings. This was typical of the fighter aircraft then in development or testing. These tests would lead to the X-3's most significant flight, and the near-loss of the aircraft.
On October 27, 1954, Walker made an abrupt left roll at Mach 0.92 and an altitude of 30,000 feet.
The X-3 rolled as expected, but also pitched up 20 degrees and yawed 16 degrees. The aircraft gyrated for five seconds before Walker was able to get it back under control. He then set up for the next test point. Walker put the X-3 into a dive, accelerating to Mach 1.154 at 32,356 feet, where he made an abrupt left roll. The aircraft pitched down and reached a g-loading of -6.7, then pitched upward to +7 Gs. At the same time, the X-3 sideslipped, resulting in a loading of 2 Gs. Walker managed to bring the X-3 under control and successfully landed.
The post-flight examination showed the fuselage had been subjected to its maximum load limit. Had the G forces been higher, the aircraft could have broken up. Walker and the X-3 had experienced "roll coupling," in which a maneuver in one axes will cause an uncommanded maneuver in one or two others. At the same time, several F-100s were involved in similar incidents. A research program was started by the NACA to understand the problem and find solutions.
( https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-077-DFRC.html )
In the pdf's from above i discovered that raising the horizontal stabilizer a couple inches helped to correct for these errors. On the F-104 which could be said is the red headed step child of the X-3 we find the horizontal stabilizer lifted into the top of the vertical stabilizer and all these problems are pretty much gone, regardless of the heavy fuselage loading..
NACA pilot Joseph A. Walker made his pilot checkout flight in the X-3 on August 23, 1954, then conducting eight research flights in September and October. By late October, the research program was expanded to include lateral and directional stability tests. In these tests, the X-3 was abruptly rolled at transonic and supersonic speeds, with the rudder kept centered. Despite its shortcomings, the X-3 was ideal for these tests. The mass of its engines, fuel and structure was concentrated in its long, narrow fuselage, while its wings were short and stubby. As a result, the X-3 was "loaded" along its fuselage, rather than its wings. This was typical of the fighter aircraft then in development or testing. These tests would lead to the X-3's most significant flight, and the near-loss of the aircraft.
On October 27, 1954, Walker made an abrupt left roll at Mach 0.92 and an altitude of 30,000 feet.
The X-3 rolled as expected, but also pitched up 20 degrees and yawed 16 degrees. The aircraft gyrated for five seconds before Walker was able to get it back under control. He then set up for the next test point. Walker put the X-3 into a dive, accelerating to Mach 1.154 at 32,356 feet, where he made an abrupt left roll. The aircraft pitched down and reached a g-loading of -6.7, then pitched upward to +7 Gs. At the same time, the X-3 sideslipped, resulting in a loading of 2 Gs. Walker managed to bring the X-3 under control and successfully landed.
The post-flight examination showed the fuselage had been subjected to its maximum load limit. Had the G forces been higher, the aircraft could have broken up. Walker and the X-3 had experienced "roll coupling," in which a maneuver in one axes will cause an uncommanded maneuver in one or two others. At the same time, several F-100s were involved in similar incidents. A research program was started by the NACA to understand the problem and find solutions.
( https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-077-DFRC.html )
In the pdf's from above i discovered that raising the horizontal stabilizer a couple inches helped to correct for these errors. On the F-104 which could be said is the red headed step child of the X-3 we find the horizontal stabilizer lifted into the top of the vertical stabilizer and all these problems are pretty much gone, regardless of the heavy fuselage loading..
They think I'm nutz!
