From Pixels to Public Health: Accelerating the Utilization of MAIA Data via NASA ASDC Services
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Sarah Scott↗
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Review of European Microgravity Measurements
AA In a French/Russion cooperation, CNES developed a microgravity detection system for analyzing the Mir space station micro-g-environment for the first time. European efforts to characterize the microgravity (1/9) environment within a space laboratory began in the late seventies with the design of the First Spacelab Mission SL-1. Its Material Science Double Rack was the first payload element to carry its own tri-axial acceleration package. Even though incapable for any frequency analysis, the data provided a wealth of novel information for optimal experiment and hardware design and operations for missions to come. Theoretical investigations under ESA contract demonstrated the significance of the detailed knowledge of micro-g data for a thorough experiment analysis. They especially revealed the high sensitivity of numerous phenomena to low frequency acceleration. Accordingly, the payloads of the Spacelab missions D-1 and D-2 were furnished with state-of-the-art detection systems to ensure frequency analysis between 0.1 and 100 Hz. The Microgravity Measurement Assembly (MMA) of D-2 was a centralized system comprising fixed installed as well as mobile tri-axial packages showing real-time data processing and transmission to ground. ESA's free flyer EURECA carried a system for continuous measurement over the entire mission. All EURECA subsystems and experimental facilities had to meet tough requirements defining the upper acceleration limits. In a French/Russion cooperation, CNES developed a mi crogravity detection system for analyzing the Mir space station micro-g-environment for the first time. An approach to get access to low frequency acceleration between 0 and 0.02 Hz will be realized by QSAM (Quasi-steady Acceleration Measurement) on IML-2, complementary to the NASA system Spacelab Acceleration Measurement System SAMS. A second flight of QSAM is planned for the Russian free flyer FOTON.
H Hamacher↗
Pressure Distribution over a Wing and Tail Rib of a VE-7 and of a TS Airplane in Flight
This investigation was made to determine the pressure distribution over a rib of the wing and over a rib of the horizontal tail surface of an airplane in flight and to obtain information as to the time correlation of the loads occurring on these ribs. Two airplanes, VE-7 and TS, were selected in order to obtain the information for a thin and a thick wing section. In each case the pressure distribution was recorded for the full range of angle of attack in level flight and throughout violent maneuvers. The results show: (a) that the present rib load specifications in use by the Army Air Corps and the Bureau of Aeronautics, Navy Department, are in fair agreement with the loads actually occurring in flight, but could be slightly improved; (b) that there appears to be no definite sequence in which wing and tail surface ribs reach their respective maximum loads in different maneuvers; (c) that in accelerated flight, at air speeds less than or equal to 60 per cent of the maximum speed, the accelerations measured agree very closely with the theoretically possible maximum accelerations. In maneuvers at higher air speeds the observed accelerations were smaller than those theoretically possible. (author)
Crowley, J W , Jr↗
Landing-shock Recorder
A description of a special type of seismograph, called a "landing-shock recorder," to be used for measuring the acceleration during impacts such as are experienced in airplane landings, is given . The theory, together with the assumptions made, is discussed in its relation to calculating the acceleration experienced in impact. Calculations are given from records obtained for two impacts of known acceleration. In one case the impact was very severe and in the other it was only moderately severe.
Brevoort, M J↗
The Effects of Slots and Flaps on Lateral Control of a Low-wing Monoplane as Determined in Flight
This paper presents the results of flight tests made to determine the effect of slots and flaps on the lateral control of a low-wing monoplane. Maximum angular accelerations in roll and yaw produced by sudden application of the ailerons and maximum accelerations in yaw produced by sudden application of the rudder during gliding flight were recorded for the following wing arrangements: (a) no auxiliary device; (b) full-span slots; (c) plain flaps; (d) flaps and full-span slots; (e) wing-tip slots. Rolling- and yawing-moment coefficients were derived from the accelerations. The full span slots and the flaps each had about the same influence on the aileron rolling moments. At values of the lift coefficient obtainable with the plain wing, the effect of these devices was negligible. At the higher lift coefficients obtainable with these devices, the rolling-moment coefficients increased slightly but, despite this increase, the aileron effectiveness progressively decreased with increasing lift coefficient, owing to the corresponding reduction in air speed. In the range covered by the tests, the effectiveness of the controls was appreciably reduced by the wing-tip slots. The adverse yawing moment of the ailerons experienced at the large lift coefficients obtained with the flaps was appreciably less than at similar lift coefficients obtained with either full-span or wing-tip slots. The yawing moments produced by the rudder were only slightly affected by the use of the auxiliary devices. The airplane was found to be laterally unstable with all combinations tested. Because of the angular velocities acquired in the time taken to deflect the ailerons the rolling moments recorded in flight were only about two thirds the values that would have been obtained with the wing restrained as in wind-tunnel tests.
WING SLOTS↗
A study of unsymmetrical-loading conditions
The force variation along the wing span under combined normal and angular accelerations is considered. Non dimensional curves of section load, shear, and moment are given for: (1) the air load that produces a normal acceleration; (2) the accompanying wing weight and normal inertia loads; (3) aileron and gust air loads that produce angular acceleration; (4) the angular inertia load of the wing. The required aerodynamic load distributions have been obtained by use of wing theory, and the wing inertia distributions are based on an analysis of wing-weight data. Several examples are included to illustrate the effect of wing taper and aileron span on the total shears and moments at any section along the span.
Pearson, Henry A↗
The R-38 Catastrophe and the Mechanics of Rigid Airship Construction
An airship frame may be regarded as a rigid girder subjected to a number of forces which, according to their nature, may be classified as follows: weight or loads (force of gravity); lifting forces (aero-static); accelerations (dynamic). These forces must be in equilibrium in the three most important cases during flight: 1) when the airship is floating (aerostatic problem); 2) when flying without acceleration (aerodynamic problem). 3) When under the influence of any accelerating force (dynamic problem). This report will briefly discuss each of these cases in regard to the R-38 airship accident.
AIRSHIPS - R-38 - ACCIDENTS (BRIT )↗
The Pressure Distribution over the Horizontal Tail Surfaces of an Airplane III
This report contains the results of an investigation of the distribution of pressure over the tail surfaces of a full-sized airplane during accelerated flight for the purpose of determining the magnitude of the tail and fuselage stresses in maneuvering. As the pressures in accelerated flight change in value with great rapidity, it was found that the liquid manometer used in the first part of this investigation would not be at all suitable under these conditions; so it was necessary to design and construct a new manometer containing a large number of recording diaphragm gauges for these measurements. Sixty openings on the tail surfaces were connected to this manometer and continuous records of pressures for each pair of holes were taken during various maneuvers. There were also recorded, simultaneously with the pressures, the normal acceleration at the center of gravity and the angular position of all the controls. The present investigation consisted in measuring on a standard rigged JN4H airplane the distribution of pressure over the whole of the horizontal tail surfaces while the airplane was being put through maneuvers as violently as it was thought safe, including spinning and pulling out of dives.
Norton, F H↗
A Study of Airplane Maneuvers with Special Reference to Angular Velocities
This investigation was undertaken by the National Advisory Committee for Aeronautics for the purpose of increasing our knowledge on the behavior of the airplane during various maneuvers and to obtain values of the maximum angular velocities and accelerations in flight. The method consisted in flying a JN4H airplane through various maneuvers while records were being taken of the control position, the air speed, the angular velocity and the acceleration along the Z axis. The results showed that the maximum angular velocity about the X axis of radians per second in a barrel roll. The maximum angular acceleration about the X axis of -2.10 radians per (second) to the 2nd power occurred in a spin, while the maximum about the Y axis was 1.40 radians per (second) to the 2nd power when pulling suddenly out of a dive. These results have direct application to the design of airplane parts, such as propeller shaft and instruments.
Reid, J E↗
GOES-R Lithium-Ion Battery Life Test & Workhorse Battery Performance
The GOES R series lithium-ion battery life test results are presented for the next-generation GOES R series weather satellites. Lockheed Martin is under contract to NASA Goddard to build and deliver four GOES-R series satellites which are operated by NOAA. In addition, Lockheed Martin is required to build a GOES R series flight battery to flight drawings and processes and perform an accelerated geosynchronous earth-orbiting (GEO) life test consisting of 30 real-time eclipse seasons and 30 accelerated solstice seasons. The GOES R series batteries are designed and built by Saft America, Inc. Space and Defense Division in Cockeysville, MD with Saft VL48E cells. The GOES R series life test battery which has been built to flight drawings and processes has undergone 21 seasons of accelerated GEO testing (which is equivalent to over 10 years on-orbit). This presentation includes a description of the life test and latest test results through season 20. The life test battery capacity measurements prior to cycling and after seasons 4, 10, and 20 which have shown little or no change are summarized. In addition, the performance of the GOES R series workhorse batteries performance are presented. These GOES R series workhorse batteries are used during spacecraft testing and have shown no discernable capacity loss after 7 years of mostly ambient operation and cold storage since activation. An overview of the electrical power subsystem and battery charge is, also, addressed.
Tucker, Jon↗
Tests of a Gust-Alleviating Wing in the Gust Tunnel
Tests were made in the NACA gust tunnel to determine the effectiveness of a torsionally flexible wing with the torsion axis ahead of the locus of the section aerodynamic centers in reducing airplane accelerations due to atmospheric gusts. For three gust shapes, a series of flights was made with the airplane model equipped with either a torsionally flexible or a rigid wing. The results indicated that the torsionally flexible wing reduced the maximum acceleration increment 5 percent for the sharp-edge gust and about 17 percent for gust shapes with gradient distances of 6.8 and 15 chord lengths. The analysis indicated that the effectiveness of this method of gust alleviation was independent of the gust velocity and that, for the same total load increment, the torsionally flexible wing would have 10 percent less bending-moment increment at the root section of the wing than a rigid wing in all but the sharpest gusts. The results also indicated that the torsionally flexible wing slightly increased the longitudinal stability of the airplane model in a gust.
Shufflebarger, C C↗
Corrosion Embrittlement of Duralumin V : Results of Weather-Exposure Tests
In a series of weather exposure tests of sheet duralumin, upon which accelerated corrosion tests in the laboratory by the wet-and-dry corrosion method in a sodium chloride solution has already been carried out, a close parallelism between the results of the two kinds of tests was found to exist. The exposure tests showed that the lack of permanence of sheet duralumin is largely, if not entirely, due to corrosion. A corrosion attack of an intercrystalline nature is very largely responsible for the degree of embrittlement produced. The rate of embrittlement was greatly accelerated by a marine atmosphere and by the tropical climate. Variations in corrosion and embrittlement are noted in relation to heat treatment, cold working, and types of protective coatings.
Rawdon, Henry S↗
Preliminary Investigation on Boundary Layer Control by Means of Suction and Pressure with the U.S.A. 27 Airfoil
The tests described in this report constitute a preliminary investigation of airfoil boundary layer control, as carried out in the atmospheric wind tunnel of the Langley Memorial Aeronautical Laboratory, from February to August, 1927. Tests were made on a U.S.A. 27 airfoil section with various slot shapes and combinations, and at various amounts of pressure or suction on the slots. The lift of airfoils can be increased by removing or by accelerating the boundary layer. Removing the boundary layer by suction is more economical than to accelerate it by jet action. Gauze-covered suction slots apparently give the best results. When not in operation, all suction slots tested had a detrimental effect upon the aerodynamic characteristics of the airfoil which was not apparent with the backward-opening pressure slots. Thick, blunt-nose airfoils would seem to give best results with boundary layer control.
Reid, E G↗
Tests of a Gust-alleviating Flap in the Gust Tunnel
Tests were made to determine the effectiveness of a long-period dynamically overbalanced flap in reducing airplane accelerations due to atmospheric gusts. For two gust shapes, one gust velocity, one forward velocity, and one wing loading, a series of flights was made with the flap locked and was then repeated with the flap free to operate. The records were evaluated by routine methods. The results indicate that the flap reduced the maximum acceleration increment 39 percent for a severe gust but with a representative gust shape (a sharp-edge gust), the reduction was only 3 percent. The results also indicate that the flap tended to reduce the longitudinal stability of the airplane. Computations made of the effectiveness and the action of the flap were in good agreement with the experimental results.
Donely, Philip↗
A Study of Taking off and Landing an Airplane
This report covers the results of an investigation carried on at the Langley Memorial Aeronautical Laboratory of the National Advisory Committee for Aeronautics for the purpose of discussing the various methods of effecting the take-off and the landing of an airplane, and to make a direct analysis of the control movements, the accelerations, and air speeds during these the maneuvers. The recording instruments developed at the laboratory were used in this test and the records obtained by them were made the basis for a comparative study of the two extreme methods of taking off (the tail-high and tail-low methods) and of various types of landings. The records should be of considerable value to a student pilot in enabling him to visualize the movements of the controls and the consequent effect upon the air speed and acceleration.
Carroll, T↗
Forces on Airships in Gusts
In this report it is shown that determining the instantaneous angle of pitch, the acceleration of the gust is as important as its maximum velocity or yaw. Hitherto it has been assumed that the conditions encountered in gusts could be approximately represented by considering the airship to be at an instantaneous angle of yaw or pitch (according to whether the gust is horizontal or vertical), the instantaneous angle being tan to the (-1) power (v/v), where v is the component of the velocity of the gust at right angles to the longitudinal axis of the ship, and v is the speed of the ship. An expression is derived for this instantaneous angle in terms of the speed and certain aerodynamic characteristics of the airship, and of the maximum velocity and the acceleration of the gust, and the application of the expression to the determination of the forces on the ship is illustrated by numerical examples.
Burgess, C P↗
The Pressure Distribution over the Wings and Tail Surfaces of a PW-9 Pursuit Airplane in Flight
This report presents the results of an investigation to determine (1) the magnitude and distribution of aerodynamic loads over the wings and tail surfaces of a pursuit-type airplane in the maneuvers likely to impose critical loads on the various subassemblies of the airplane structure. (2) To study the phenomenon of center of pressure movement and normal force coefficient variation in accelerated flight, and (3) to measure the normal accelerations at the center of gravity, wing-tip, and tail, in order to determine the nature of the inertia forces acting simultaneously with the critical aerodynamic loads. The results obtained throw light on a number of important questions involving structural design. Some of the more interesting results are discussed in some detail, but in general the report is for the purpose of making this collection of airplane-load data obtained in flight available to those interested in airplane structures.
Rhode, Richard↗
Dynamic and Flight Tests on Rubber-Cord and Oleo-Rubber-Disk Landing Gears for an F6C-4 Airplane
The investigation described in this report was conducted for the purpose of comparing an oleo-rubber-disk and a rubber-cord landing gear, built for use on an F6C-4 airplane. The investigation consisted of drop tests under various loading conditions and flight tests on an F6C-4 airplane. In the drop tests the total work done on each gear and the work done on each of the shock-absorbing units were determined. For both drop tests and flight tests the maximum loads and accelerations were determined. The comparative results showed that the oleo gear was slightly superior in reducing the ordinary landing shocks, that it had a greater capacity for work, and that it was very superior in the reduction of the rebound. The results further showed that for drops comparable to very severe landings, the rubber-cord gear was potentially more effective as a shock-reducing mechanism. However, due to the construction of this chassis, which limited the maximum elongation of the cords, this gear was incapable of withstanding as severe tests as the oleo gear. The action of the oleo gear was greatly inferior to the action of an ideal gear. The maximum accelerations encountered during the flight tests for severe landings were 3.64g for the rubber-cord gear and 2.27g for the oleo gear. These were less than those experienced in free drops of 7 inches on either gear.
Peck, William C↗