X-15 on lakebed Credit: NASA. 11,369 bytes. 492 x 148 pixels.

Manned hypersonic research rocket aircraft.

Liftoff Thrust: 23,174 kgf. Total Mass: 14,184 kg. Core Diameter: 1.4 m. Total Length: 15.3 m.

• Stage Number: 0. 1 x NB-52 Gross Mass: 177,273 kg. Empty Mass: 70,545 kg. Thrust (vac): 43,896 kgf. Isp: 5,142 sec. Burn time: 48,000 sec. Isp(sl): 4,675 sec. Diameter: 14.7 m. Span: 56.4 m. Length: 47.7 m. Propellants: Air/Kerosene No Engines: 8. J57-19

• Stage Number: 2. 1 x X-15A Gross Mass: 14,184 kg. Empty Mass: 5,158 kg. Thrust (vac): 26,762 kgf. Isp: 276 sec. Burn time: 90 sec. Isp(sl): 239 sec. Diameter: 1.4 m. Span: 6.8 m. Length: 15.3 m. Propellants: Lox/Ammonia No Engines: 1. XLR-99

• X-15 project begun. Spacecraft: X-15A.

  NACA met with USAF and Navy BuAer representatives to propose the X-15 as an extension of the cooperative rocket research aircraft program. The NACA proposal was accepted as a joint effort and a memorandum of understanding was signed on December 23 naming NACA as technical director of the project, with advice from a joint Research Airplane Committee.

• X-15 first public details announced. Spacecraft: X-15A.

  Details of X-15 rocket research airplane were publicly revealed for the first time.

• X-15 rollout. Spacecraft: X-15A.

  First of a series of three X-15 experimental rocket-powered manned research aircraft was rolled out at the Los Angeles plant of North American Aviation, Inc., in the joint USAF-USN-NASA program.

• X-15 Flight 1 Spacecraft: X-15A.

  First flight for X-15 # 1. Planned glide flight. Maximum Speed - 840 kph. Maximum Altitude - 11445 m.

• X-15 Flight 2 Spacecraft: X-15A.

  First flight for X-15 # 2. First powered flight. Maximum Speed - 2241 kph. Maximum Altitude - 15954 m. Turbopump case failure resulted in fire in engine compartment.

• X-15 Flight 3 Spacecraft: X-15A.

  Maximum Speed - 2283 kph. Maximum Altitude - 18831 m. Nose gear door failed on landing.

• X-15 Flight 4 Spacecraft: X-15A.

  Engine fire; fuselage structural failure on landing. Aircraft returned to North American for rebuild. Maximum Speed - 1062 kph. Maximum Altitude - 13857 m.

• X-15 Flight 5 Spacecraft: X-15A.

  Maximum Speed - 2685 kph. Maximum Altitude - 20374 m.

• X-15 Flight 6 Spacecraft: X-15A.

  Maximum Speed - 2359 kph. Maximum Altitude - 26858 m.

• X-15 Flight 7 Spacecraft: X-15A.

  Maximum Speed - 1667 kph. Maximum Altitude - 16045 m. Automatic shutdown of one chamber in upper XLR-11.

• X-15 Flight 8 Spacecraft: X-15A.

  Maximum Speed - 2283 kph. Maximum Altitude - 16045 m. 6G maneuver test.

• X-15 Flight 9 Spacecraft: X-15A.

  Maximum Speed - 2124 kph. Maximum Altitude - 14822 m. Roll damper malfunctioned.

• X-15 Flight 10 Spacecraft: X-15A.

  Maximum Speed - 2080 kph. Maximum Altitude - 15235 m.

• X-15 Flight 11 Spacecraft: X-15A.

  Maximum Speed - 2156 kph. Maximum Altitude - 15653 m. 3.5 to 5G pullouts to simulate reentry.

• X-15 Flight 12 Spacecraft: X-15A.

  Maximum Speed - 2018 kph. Maximum Altitude - 14630 m.

• X-15 Flight 13 Spacecraft: X-15A.

  Maximum Speed - 2718 kph. Maximum Altitude - 18134 m.

• X-15 Flight 14 Spacecraft: X-15A.

  Maximum Speed - 2336 kph. Maximum Altitude - 18574 m.

• X-15 Flight 15 Spacecraft: X-15A.

  Maximum Speed - 3397 kph. Maximum Altitude - 23738 m.

• X-15 Flight 16 Spacecraft: X-15A.

  Maximum Speed - 2558 kph. Maximum Altitude - 33222 m.

• X-15 Flight 17 Spacecraft: X-15A.

  Maximum Speed - 2336 kph. Maximum Altitude - 15631 m. First test of reaction control system.

• X-15 Flight 18 Spacecraft: X-15A.

  Maximum Speed - 3533 kph. Maximum Altitude - 23809 m. Unofficial world speed record. This topped Captain Apt's speed of 2,094 mph attained in the X-2 on September 27, 1956.

• X-15 Flight 19 Spacecraft: X-15A.

  Maximum Speed - 2851 kph. Maximum Altitude - 41605 m. Established a new altitude record for a manned vehicle of 136,500 feet. This topped Captain Kincheloe's record altitude of 126,200 feet attained on September 7, 1956, in the X-2 rocket research aircraft.

• X-15 Flight 20 Spacecraft: X-15A.

  Maximum Speed - 3195 kph. Maximum Altitude - 23159 m.

• X-15 Flight 21 Spacecraft: X-15A.

  Maximum Speed - 3510 kph. Maximum Altitude - 24343 m.

• X-15 Flight 22 Spacecraft: X-15A.

  Maximum Speed - 1783 kph. Maximum Altitude - 16168 m. Premature shutdown of both XLR-11's.

• X-15 Flight 23 Spacecraft: X-15A.

  Maximum Speed - 2059 kph. Maximum Altitude - 16398 m.

• X-15 Flight 24 Spacecraft: X-15A.

  Maximum Speed - 2145 kph. Maximum Altitude - 15453 m.

• X-15 Flight 25 Spacecraft: X-15A.

  Maximum Speed - 2071 kph. Maximum Altitude - 14905 m.

• X-15 Flight 26 Spacecraft: X-15A.

  First flight with XLR-99 engine. Maximum Speed - 3154 kph. Maximum Altitude - 24750 m.

• X-15 Flight 27 Spacecraft: X-15A.

  Maximum Speed - 2018 kph. Maximum Altitude - 16688 m. Lower XLR-11 shutdown but restarted.

• X-15 Flight 28 Spacecraft: X-15A.

  First restart with XLR-99 engine. Maximum Speed - 2665 kph. Maximum Altitude - 18867 m.

• X-15 Flight 29 Spacecraft: X-15A.

  Maximum Speed - 1858 kph. Maximum Altitude - 14886 m. Only 7 of 8 XLR-11 chambers ignited.

• X-15 Flight 30 Spacecraft: X-15A.

  Maximum Speed - 3027 kph. Maximum Altitude - 16268 m.

• X-15 Flight 31 Spacecraft: X-15A.

  First hot nose flight. Maximum Speed - 1911 kph. Maximum Altitude - 15269 m.

• X-15 Flight 32 Spacecraft: X-15A.

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  X-15C 3-view Credit: © Mark Wade. 2,441 bytes. 388 x 282 pixels.

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  Maximum Speed - 1949 kph. Maximum Altitude - 15170 m.

• X-15 Flight 33 Spacecraft: X-15A.

  Maximum Speed - 3660 kph. Maximum Altitude - 23820 m. Last XLR-11 flight.

• X-15 Flight 34 Spacecraft: X-15A.

  Maximum Speed - 4674 kph. Maximum Altitude - 23610 m.

• X-15 Flight 35 Spacecraft: X-15A.

  Maximum Speed - 4441 kph. Maximum Altitude - 51700 m.

• X-15 Flight 36 Spacecraft: X-15A.

  Maximum Speed - 4946 kph. Maximum Altitude - 32000 m.

• X-15 Flight 37 Spacecraft: X-15A.

  Maximum Speed - 5321 kph. Maximum Altitude - 32850 m.

• X-15 awards. Spacecraft: X-15A.

  Harmon International Aviator's Trophy for 1961 announced as going to three winners for the first time-X-15 rocket research airplane pilots: A. Scott Crossfield, of North American; Joseph A. Walker, of NASA, and Maj. Robert A. White, U.S. Air Force.

• X-15 Flight 38 Spacecraft: X-15A.

  Maximum Speed - 5797 kph. Maximum Altitude - 32830 m. Lost cabin pressure.

• X-15 Flight 39 Spacecraft: X-15A.

  Maximum Speed - 4401 kph. Maximum Altitude - 23830 m. Lost cabin pressure.

• X-15 Flight 40 Spacecraft: X-15A.

  Maximum Speed - 5821 kph. Maximum Altitude - 34840 m. Smoke in cockpit due to scorching paint.

• X-15 Flight 41 Spacecraft: X-15A.

  Maximum Speed - 5792 kph. Maximum Altitude - 31030 m. Test reentry heat limit. Smoke in cockpit due to scorching paint.

• X-15 Flight 42 Spacecraft: X-15A.

  Flight made with lower ventral off. Maximum Speed - 4553 kph. Maximum Altitude - 23770 m.

• X-15 Flight 43 Spacecraft: X-15A.

  Outer panel of left windshield cracked. Maximum Speed - 5868 kph. Maximum Altitude - 66150 m.

• X-15 Flight 44 Spacecraft: X-15A.

  Maximum Speed - 6275 kph. Maximum Altitude - 33100 m.

• X-15 Flight 45 Spacecraft: X-15A.

  Design speed achieved. Outer right windshield shattered. Maximum Speed - 6586 kph. Maximum Altitude - 30950 m.

• X-15 Flight 46 Spacecraft: X-15A.

  First flight for X-15 # 3. Maximum Speed - 4026 kph. Maximum Altitude - 24700 m.

• X-15 Flight 47 Spacecraft: X-15A.

  Emergency landing on Mud Lake after engine failed to light. Maximum Speed - 1038 kph. Maximum Altitude - 13,640 m.

• X-15 Flight 48 Spacecraft: X-15A.

  Maximum Speed - 6058 kph. Maximum Altitude - 40690 m.

• X-15 Flight 49 Spacecraft: X-15A.

  Maximum Speed - 4586 kph. Maximum Altitude - 54860 m. The X-15 was flown in a test of a new automatic control system to be used in the Dyna-Soar and Apollo spacecraft. The previous electronic control system had been automatic only while the X-15 was in the atmosphere; the new system was automatic in space as well.

• X-15 Flight 50 Spacecraft: X-15A.

  Maximum Speed - 6220 kph. Maximum Altitude - 46940 m.

• X-15 Flight 51 Spacecraft: X-15A.

  Maximum Speed - 6097 kph. Maximum Altitude - 63250 m.

• X-15 Flight 80 Spacecraft: X-15A.

  Maximum Speed - 5879 kph. Maximum Altitude - 32160 m.

• X-15 Flight 52 Spacecraft: X-15A.

  Design altitude flight. Maximum Speed - 5614 kph. Maximum Altitude - 75190 m.

• X-15 Flight 53 Spacecraft: X-15A.

  Maximum Speed - 5670 kph. Maximum Altitude - 21460 m.

• X-15 Flight 54 Spacecraft: X-15A.

  Maximum Speed - 5551 kph. Maximum Altitude - 30600 m. Roller coaster flight with 3 peaks for local airflow investigation.

• X-15 Flight 55 Spacecraft: X-15A.

  Maximum Speed - 5913 kph. Maximum Altitude - 40420 m. Steepest reentry descent with highest angle of attack (27 degrees) to date.

• X-15 Flight 56 Spacecraft: X-15A.

  Maximum Speed - 5908 kph. Maximum Altitude - 31580 m.

• X-15 Flight 57 Spacecraft: X-15A.

  Maximum Speed - 5659 kph. Maximum Altitude - 56270 m.

• X-15 Flight 58 Spacecraft: X-15A.

  Maximum Speed - 5858 kph. Maximum Altitude - 75190 m.

• X-15 Flight 59 Spacecraft: X-15A.

  Unofficial world speed record. Maximum Speed - 6603 kph. Maximum Altitude - 37700 m.

• X-15 Flight 60 Spacecraft: X-15A.

  Maximum Speed - 5278 kph. Maximum Altitude - 25360 m.

• X-15 Flight 61 Spacecraft: X-15A.

  Maximum Speed - 5911 kph. Maximum Altitude - 32670 m.

• X-15 Flight 62 Spacecraft: X-15A.

  FAI world altitude record. Maximum Speed - 6166 kph. Maximum Altitude - 95940 m. First astronaut wings flight (USAF definition).

• X-15 Flight 63 Spacecraft: X-15A.

  Maximum Speed - 5590 kph. Maximum Altitude - 25680 m.

• X-15 Flight 64 Spacecraft: X-15A.

  Maximum Speed - 6418 kph. Maximum Altitude - 30150 m. Roller coaster descent to simulate emergency reentry.

• X-15 Flight 65 Spacecraft: X-15A.

  Maximum Speed - 5532 kph. Maximum Altitude - 44040 m.

• X-15 Flight 66 Spacecraft: X-15A.

  Maximum Speed - 4735 kph. Maximum Altitude - 27700 m.

• X-15 Flight 67 Spacecraft: X-15A.

  Maximum Speed - 6029 kph. Maximum Altitude - 59010 m. New reentry technique using pitch angle instrument instead of AOA.

• X-15 Flight 68 Spacecraft: X-15A.

  Maximum Speed - 5686 kph. Maximum Altitude - 27000 m.

• X-15 Flight 69 Spacecraft: X-15A.

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  X-15 3 View Credit: © Mark Wade. 1,359 bytes. 203 x 282 pixels.

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  Maximum Speed - 5546 kph. Maximum Altitude - 29630 m.

• X-15 Flight 70 Spacecraft: X-15A.

  This and most following flights without lower ventral. Maximum Speed - 4450 kph. Maximum Altitude - 20790 m.

• X-15 Flight 71 Spacecraft: X-15A.

  Maximum Speed - 5620 kph. Maximum Altitude - 34200 m.

• X-15 Flight 72 Spacecraft: X-15A.

  Maximum Speed - 5979 kph. Maximum Altitude - 39700 m.

• X-15 Flight 73 Spacecraft: X-15A.

  Maximum Speed - 6056 kph. Maximum Altitude - 41000 m.

• X-15 Flight 74 Spacecraft: X-15A.

  Engine only produced 35% power. Emergency landing at Mud Lake. Aircraft seriously damaged when gear failed. McKay injured. Maximum Speed - 1640 kph. Maximum Altitude - 16450 m.

• X-15 Flight 75 Spacecraft: X-15A.

  Maximum Speed - 6021 kph. Maximum Altitude - 43100 m.

• X-15 Flight 76 Spacecraft: X-15A.

  Maximum Speed - 6103 kph. Maximum Altitude - 48900 m.

• X-15 Flight 77 Spacecraft: X-15A.

  First civilian flight above 80 km. Maximum Speed - 5917 kph. Maximum Altitude - 82810 m. Second astronaut wings flight (USAF definition).

• X-15 Flight 78 Spacecraft: X-15A.

  Maximum Speed - 4608 kph. Maximum Altitude - 22680 m. First flight in scientific and advanced research series - carried aerial mapping camera.

• X-15 Flight 79 Spacecraft: X-15A.

  Nose landing gear failed. Maximum Speed - 6066 kph. Maximum Altitude - 28190 m.

• X-15 Flight 81 Spacecraft: X-15A.

  Maximum Speed - 5612 kph. Maximum Altitude - 63820 m. Carried earth background radiation instrument in support of Midas reconnsat development.

• X-15 Flight 82 Spacecraft: X-15A.

  Maximum Speed - 5792 kph. Maximum Altitude - 29140 m.

• X-15 Flight 83 Spacecraft: X-15A.

  Maximum Speed - 6204 kph. Maximum Altitude - 37860 m. Lost both nose landing gear tires and forward fuselage buckled after APU gear box pressure loss.

• X-15 Flight 84 Spacecraft: X-15A.

  Inner panel of left windshield cracked. Maximum Speed - 6208 kph. Maximum Altitude - 28040 m.

• X-15 Flight 85 Spacecraft: X-15A.

  Maximum Speed - 5694 kph. Maximum Altitude - 68180 m.

• X-15 Flight 86 Spacecraft: X-15A.

  Maximum Speed - 6293 kph. Maximum Altitude - 34080 m.

• X-15 Flight 87 Spacecraft: X-15A.

  Maximum Speed - 5511 kph. Maximum Altitude - 86870 m. Third astronaut wings flight (USAF definition).

• X-15 Flight 88 Spacecraft: X-15A.

  Maximum Speed - 5842 kph. Maximum Altitude - 69010 m.

• X-15 Flight 89 Spacecraft: X-15A.

  Maximum Speed - 6315 kph. Maximum Altitude - 31940 m.

• X-15 Flight 90 Spacecraft: X-15A.

  Maximum Speed - 5969 kph. Maximum Altitude - 106010 m. Astronaut wings flight. 80 cm diameter balloon dragged on 30 m line to measure air density. First X-15 astronaut flight (FAI definition); fourth astronaut wings flight (USAF definition).

• X-15 Flight 91 Spacecraft: X-15A.

  Unofficial world altitude record. Maximum Speed - 6105 kph. Maximum Altitude - 107960 m. Second X-15 astronaut flight (FAI definition); fifth astronaut wings flight (USAF definition).

• X-15 Flight 92 Spacecraft: X-15A.

  Maximum Speed - 4560 kph. Maximum Altitude - 23710 m.

• X-15 Flight 93 Spacecraft: X-15A.

  Maximum Speed - 4364 kph. Maximum Altitude - 22600 m.

• X-15 Flight 94 Spacecraft: X-15A.

  Maximum Speed - 4706 kph. Maximum Altitude - 25080 m. First flight with sharp-edged vertical stabilizer.

• X-15 Flight 95 Spacecraft: X-15A.

  Maximum Speed - 5287 kph. Maximum Altitude - 27680 m.

• X-15 Flight 96 Spacecraft: X-15A.

  Maximum Speed - 5326 kph. Maximum Altitude - 27371 m.

• X-15 Flight 97 Spacecraft: X-15A.

  Maximum Speed - 6465 kph. Maximum Altitude - 30785 m. Camera test in combination with U-2 flight.

• X-15 Flight 98 Spacecraft: X-15A.

  Maximum Speed - 5818 kph. Maximum Altitude - 42642 m.

• X-15 Flight 99 Spacecraft: X-15A.

  Maximum Speed - 5216 kph. Maximum Altitude - 21641 m.

• X-15 Flight 100 Spacecraft: X-15A.

  Maximum Speed - 5821 kph. Maximum Altitude - 32736 m. First test of hypersonic speed brakes.

• X-15 Flight 101 Spacecraft: X-15A.

  Maximum Speed - 5662 kph. Maximum Altitude - 23957 m.

• X-15 Flight 102 Spacecraft: X-15A.

  Maximum Speed - 5458 kph. Maximum Altitude - 23165 m.

• X-15 Flight 103 Spacecraft: X-15A.

  Maximum Speed - 6158 kph. Maximum Altitude - 30937 m. Secret reconn camera test.

• X-15 Flight 104 Spacecraft: X-15A.

  Maximum Speed - 5580 kph. Maximum Altitude - 53340 m.

• X-15 Flight 105 Spacecraft: X-15A.

  Maximum Speed - 6285 kph. Maximum Altitude - 30968 m.

• X-15 Flight 106 Spacecraft: X-15A.

  Maximum Speed - 4962 kph. Maximum Altitude - 22189 m.

• X-15 Flight 107 Spacecraft: X-15A.

  Maximum Speed - 5262 kph. Maximum Altitude - 59680 m.

• X-15 Flight 108 Spacecraft: X-15A.

  Premature engine shutdown at 41 sec. Maximum Speed - 3001 kph. Maximum Altitude - 19568 m.

• X-15 Flight 110 Spacecraft: X-15A.

  Maximum Speed - 5364 kph. Maximum Altitude - 30358 m.

• X-15 Flight 111 Spacecraft: X-15A.

  Maximum Speed - 5664 kph. Maximum Altitude - 51938 m. First test of IR horizon scanner.

• X-15 Flight 112 Spacecraft: X-15A.

  Maximum Speed - 5250 kph. Maximum Altitude - 23774 m. First test of various heat-resistant panels attached to fuselage.

• X-15 Flight 113 Spacecraft: X-15A.

  Maximum Speed - 5688 kph. Maximum Altitude - 24750 m.

• X-15 Flight 115 Spacecraft: X-15A.

  Maximum Speed - 6216 kph. Maximum Altitude - 27737 m.

• X-15 Flight 116 Spacecraft: X-15A.

  Maximum Speed - 5817 kph. Maximum Altitude - 23957 m.

• X-15 Flight 117 Spacecraft: X-15A.

  Maximum Speed - 6256 kph. Maximum Altitude - 29566 m.

• X-15 Flight 119 Spacecraft: X-15A.

  Maximum Speed - 4904 kph. Maximum Altitude - 25878 m. First flight with X-20 INS and wing tip pods.

• X-15 Flight 120 Spacecraft: X-15A.

  Maximum Speed - 5009 kph. Maximum Altitude - 25786 m.

• X-15 Flight 122 Spacecraft: X-15A.

  Maximum Speed - 5990 kph. Maximum Altitude - 28164 m.

• X-15 Flight 123 Spacecraft: X-15A.

  Maximum Speed - 5913 kph. Maximum Altitude - 34503 m.

• X-15 Flight 124 Spacecraft: X-15A.

  Maximum Speed - 5781 kph. Maximum Altitude - 24750 m.

• X-15 Flight 125 Spacecraft: X-15A.

  Maximum Speed - 5973 kph. Maximum Altitude - 30297 m. Immediately after burnout aircraft gyrated around all 3 axes for 7 seconds.

• X-15 Flight 126 Spacecraft: X-15A.

  Maximum Speed - 6253 kph. Maximum Altitude - 29931 m.

• X-15 Flight 128 Spacecraft: X-15A.

  Maximum Speed - 6034 kph. Maximum Altitude - 46817 m.

• X-15 Flight 129 Spacecraft: X-15A.

  Maximum Speed - 5760 kph. Maximum Altitude - 31059 m.

• X-15 Flight 130 Spacecraft: X-15A.

  Maximum Speed - 5760 kph. Maximum Altitude - 24293 m.

• X-15 Flight 133 Spacecraft: X-15A.

  Maximum Speed - 5100 kph. Maximum Altitude - 54803 m.

• X-15 Flight 134 Spacecraft: X-15A.

  Maximum Speed - 6040 kph. Maximum Altitude - 63886 m.

• X-15 Flight 135 Spacecraft: X-15A.

  Maximum Speed - 5477 kph. Maximum Altitude - 74585 m.

• X-15 Flight 136 Spacecraft: X-15A.

  Maximum Speed - 5697 kph. Maximum Altitude - 33071 m.

• X-15 Flight 138 Spacecraft: X-15A.

  Maximum Speed - 5522 kph. Maximum Altitude - 85527 m. Astronaut wings flight (USAF definition).

• X-15 Flight 140 Spacecraft: X-15A.

  Maximum Speed - 6050 kph. Maximum Altitude - 32126 m.

• X-15 Flight 142 Spacecraft: X-15A.

  Maximum Speed - 5686 kph. Maximum Altitude - 31455 m.

• X-15 Flight 143 Spacecraft: X-15A.

  Maximum Speed - 5712 kph. Maximum Altitude - 82601 m. Astronaut wings flight (USAF definition).

• X-15 Flight 144 Spacecraft: X-15A.

  Maximum Speed - 5799 kph. Maximum Altitude - 65258 m.

• X-15 Flight 145 Spacecraft: X-15A.

  Maximum Speed - 5426 kph. Maximum Altitude - 73030 m.

• X-15 Flight 147 Spacecraft: X-15A.

  Maximum Speed - 5686 kph. Maximum Altitude - 29627 m.

• X-15 Flight 148 Spacecraft: X-15A.

  Maximum Speed - 5662 kph. Maximum Altitude - 72847 m.

• X-15 Flight 149 Spacecraft: X-15A.

  Maximum Speed - 5712 kph. Maximum Altitude - 30571 m.

• X-15 Flight 150 Spacecraft: X-15A.

  Maximum Speed - 6005 kph. Maximum Altitude - 90099 m. Astronaut wings flight (USAF definition).

• X-15 Flight 151 Spacecraft: X-15A.

  Maximum Speed - 4373 kph. Maximum Altitude - 23350 m.

• X-15 Flight 152 Spacecraft: X-15A.

  Maximum Speed - 5001 kph. Maximum Altitude - 28770 m.

• X-15 Flight 153 Spacecraft: X-15A.

  Maximum Speed - 5718 kph. Maximum Altitude - 81230 m. Astronaut wings flight (USAF definition).

• X-15 Flight 154 Spacecraft: X-15A.

  Maximum Speed - 5662 kph. Maximum Altitude - 72210 m.

• X-15 Flight 156 Spacecraft: X-15A.

  Maximum Speed - 4450 kph. Maximum Altitude - 24440 m.

• X-15 Flight 157 Spacecraft: X-15A.

  Premature engine shutdown at 32 sec. Maximum Speed - 2307 kph. Maximum Altitude - 20850 m.

• X-15 Flight 160 Spacecraft: X-15A.

  Maximum Speed - 5876 kph. Maximum Altitude - 39620 m.

• X-15 Flight 161 Spacecraft: X-15A.

  Maximum Speed - 5176 kph. Maximum Altitude - 29290 m. First flight with X-20 energy management system.

• X-15 Flight 163 Spacecraft: X-15A.

  Maximum Speed - 5957 kph. Maximum Altitude - 73700 m.

• X-15 Flight 165 Spacecraft: X-15A.

  Maximum Speed - 6376 kph. Maximum Altitude - 40450 m.

• X-15 Flight 166 Spacecraft: X-15A.

  Maximum Speed - 5776 kph. Maximum Altitude - 76500 m.

• X-15 Flight 168 Spacecraft: X-15A.

  Maximum Speed - 5804 kph. Maximum Altitude - 54250 m.

• X-15 Flight 169 Spacecraft: X-15A.

  Maximum Speed - 5701 kph. Maximum Altitude - 78490 m. Collected micrometeorites and extraterrestrial dust.

• X-15 Flight 171 Spacecraft: X-15A.

  Premature engine shutdown at 38 sec. Maximum Speed - 2578 kph. Maximum Altitude - 22310 m.

• X-15 Flight 172 Spacecraft: X-15A.

  Maximum Speed - 5770 kph. Maximum Altitude - 22980 m. JPL spectrometer measured solar flux; radiometer characterized exhaust plume in UV for reconnsat sensors; collected micrometeorites.

• X-15 Flight 173 Spacecraft: X-15A.

  Maximum Speed - 4666 kph. Maximum Altitude - 22980 m. Engine shut down at 90 seconds.

• X-15 Flight 174 Spacecraft: X-15A.

  Maximum Speed - 6034 kph. Maximum Altitude - 93540 m. Astronaut wings flight (USAF definition).

• X-15 Flight 176 Spacecraft: X-15A.

  Maximum Speed - 5020 kph. Maximum Altitude - 28040 m.

• X-15 Flight 177 Spacecraft: X-15A.

  Maximum Speed - 6150 kph. Maximum Altitude - 40570 m. Inertial system failed after peak altitude; cabin pressurization lost during descent.

• X-15 Flight 178 Spacecraft: X-15A.

  Maximum Speed - 1871 kph. Maximum Altitude - 16280 m.

• X-15 Flight 179 Spacecraft: X-15A.

  Maximum Speed - 5985 kph. Maximum Altitude - 50900 m.

• X-15 Flight 181 Spacecraft: X-15A.

  Maximum Speed - 5112 kph. Maximum Altitude - 21670 m.

• X-15 Flight 182 Spacecraft: X-15A.

  Maximum Speed - 5802 kph. Maximum Altitude - 69890 m.

• X-15 Flight 183 Spacecraft: X-15A.

  Maximum Speed - 5810 kph. Maximum Altitude - 25050 m.

• X-15 Flight 184 Spacecraft: X-15A.

  Electrical failure while climbing through 32610 m; lost engine at 69 seconds; landed at Mud Lake with no flaps; Knight injured while exiting aircraft. Maximum Speed - 4618 kph. Maximum Altitude - 52730 m.

• X-15 Flight 185 Spacecraft: X-15A.

  Maximum Speed - 5942 kph. Maximum Altitude - 25720 m.

• X-15 Flight 187 Spacecraft: X-15A.

  Maximum Speed - 5012 kph. Maximum Altitude - 25720 m.

• X-15 Flight 189 Spacecraft: X-15A.

  Maximum Speed - 7270 kph. Maximum Altitude - 76530 m.

• X-15 Flight 190 Spacecraft: X-15A.

  Maximum Speed - 6204 kph. Maximum Altitude - 85500 m. Astronaut wings flight (USAF definition).

• X-15 Flight 191 Spacecraft: X-15A.

  Fatal accident, aircraft destroyed. After reaching peak altitude, entered spin at Mach 5. Entered dive at 30,000 m, began high frequency pitch oscillations, disintegrated when these reached 15 Gs.Maximum Speed - 5744 kph. Maximum Altitude - 81080 m.

• X-15 Flight 192 Spacecraft: X-15A.

  Maximum Speed - 4631 kph. Maximum Altitude - 31850 m. Tested Saturn V insulation.

• X-15 Flight 193 Spacecraft: X-15A.

  Maximum Speed - 5808 kph. Maximum Altitude - 57150 m.

• X-15 Flight 194 Spacecraft: X-15A.

  Maximum Speed - 5704 kph. Maximum Altitude - 63090 m.

• X-15 Flight 195 Spacecraft: X-15A.

  Maximum Speed - 5733 kph. Maximum Altitude - 67090 m.

• X-15 Flight 196 Spacecraft: X-15A.

  Maximum Speed - 5442 kph. Maximum Altitude - 67510 m.

• X-15 Flight 197 Spacecraft: X-15A.

  Maximum Speed - 5540 kph. Maximum Altitude - 81530 m. Astronaut wings flight (USAF definition).

• X-15 Flight 198 Spacecraft: X-15A.

  Maximum Speed - 5990 kph. Maximum Altitude - 77450 m.

• X-15 Flight 199 Spacecraft: X-15A.

  Last flight. Maximum Speed - 5979 kph. Maximum Altitude - 77720 m.

• 22 - Gatland, Kenneth, Manned Spacecraft, Macmillan, New York, 1968.
• 38 - Guenther, Ben, Miller, Jay, and Panopalis, Terry,, North American X-15/X-15A-2, Aerofax, Arlington, Texas, 1985.
• 48 - Miller, Jay,, The X-Planes, Aerofax, Arlington, Texas, 1988.