Lanterna Rally
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Scientific and Technical Aerospace Reports
X-15 Research Results
Investigation of the Aerodynamic Characteristics of a 0.067-scale Model of the X-15 Airplane (configuration 3) at Mach Numbers of 2.29, 2.98, and 4.65
Aerodynamic and Landing Measurements Obtained During the First Powered Flight of the North American X-15 Research Airplane
Aerodynamic Characteristics of a 0.0667-scale Model of the North American X-15 Research Airplane at Transonic Speeds
Flight Investigation at High Speeds of Profile Drag of Wing of a P-47D Airplane Having Production Surfaces Covered with Camouflage Paint
Author: John A. Zalovcik
Publisher:
Published: 1946
Total Pages: 22
ISBN-13:
DOWNLOAD EBOOK →Summary: A flight investigation was made at high speeds to determine the profile drag of a P-47D airplane wing having production surfaces covered with camouflage paint. The profile drag of a wing section somewhat out-board of the flap was determined by means of wake surveys in tests made over a range of airplane lift coefficients from 0.06 to 0.69 and airplane Mach numbers from 0.25 to 0.78. The results of the tests indicated that a minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach numbers less than 0.67. Below the Mach number at which compressibility shock occurred, variations in Mach number of as much as 0.2 appeared to have no effect on profile-drag coefficient. The variation in Reynolds number corresponding to this variation in Mach number, however, was appreciable and may have had some effect on the results obtained. Comparison of the Mach number at which shock losses were first evident in the wake with the critical Mach number indicated that shock was not evident until the critical Mach number was exceeded by at least 0.025.
Flight Investigation at High Speeds of Flow Conditions Over an Airplane Wing as Indicated by Surface Tufts
Author: Clotaire Wood
Publisher:
Published: 1945
Total Pages: 28
ISBN-13:
DOWNLOAD EBOOK →Summary: Flight tests were made at high speeds with a P-47D airplane to determine the flow characteristics, as indicated by wool tufts, on a section of the upper surface of the wing. The behavior of the tufts, which were distributed over a section of the wing from 39.5 to 52.5 percent semispan, was determined from motion pictures. The tests were made in straight flight and in turns under conditions in which airplane lift coefficients from 0.10 to 0.54 and airplane Mach numbers from 0.58 to 0.78 were obtained. The results of the tests indicated that the flow remained smooth over the test panel until the critical Mach number of the panel was exceeded by 0.08 at a lift coefficient of 0.10 and by 0.05 at a lift coefficient of 0.50. Beyond these Mach numbers, the tufts indicated unsteadiness of flow and, finally, local separation when the Mach number exceeded the critical value by 0.13 at a lift coefficient of 0.10 and by 0.10 at a lift coefficient of 0.50. The region of separated flow originated in the neighborhood of 30 percent chord at high lift coefficients and 45 percent chord at low lift coefficients. Separation appeared to extend over not more than 15 percent chord.
Preliminary Flight Research on an All-movable Horizontal Tail as a Longitudinal Control for Flight at High Mach Numbers
Author: Harold F. Kleckner
Publisher:
Published: 1945
Total Pages: 22
ISBN-13:
DOWNLOAD EBOOK →Summary: The NACA is conducting flight tests of an all-movable horizontal tail installed on a Curtiss XP-42 airplane because of its possible advantages as a longitudinal control for flight at high Mach numbers. The results are presented for some preliminary tests in the low-speed range for which the tail was very closely balanced aerodynamically and a bobweight was used to obtain stable stick-force variations with speed and acceleration. For these tests, the tail was hinged at 0.24 chord and was tried with two arrangements of servotab control. The elevator control was found to be unsatisfactory with the control arrangements tested. Although there were sufficient variation of stick force with acceleration in steady turns and a stable stick-force variation with speed, the near-zero variation of stick force with stick deflection resulted in an extremely sensitive control that required continuous attention in order to avoid motions of the airplane due to inadvertent movements of the control stick. For subsequent tests, the servotabs are being connected as geared unbalancing tabs in order that more conventional elevator hinge-moment characteristics may be obtained. The expected advantages of the all-movable tail with a control system utilizing tabs would of course be limited to flight at Mach numbers below those for which severe compressibility effects are encountered on the tail itself. For higher Mach numbers, the all-movable tail would require an irreversible power-boost control in order to handle the large hinge-moment increases that are expected.
Flight Investigation at High Mach Numbers of Several Methods of Measuring Static Pressure on an Airplane Wing
Author: John A. Zalovcik
Publisher:
Published: 1944
Total Pages: 26
ISBN-13:
DOWNLOAD EBOOK →Summary: A flight investigation was made to compare static pressures in subsonic and supersonic flow over an airplane wing as measured by static-pressure tubes, a static-pressure belt, and orifices flush with the wing surface. The measurements were made on the upper surface of the wing of the P-47D airplane over a range of flight conditions in which local Mach numbers from 0.34 to 1.41 were obtained at the measurement stations. For some of the tests, a total-pressure tube was mounted on the wing surface to determine its characteristics in supersonic flow. The results indicated that static-pressure measurements obtained with suitably designed and installed flush orifices, static-pressure tubes, and static-pressure belt will be in reasonable agreement for both subsonic and supersonic flow. The pressures in supersonic flow measured by the total-pressure tube mounted on the wing surface were found to be in close agreement with values predicted by theory.
