Dynamic stability characteristics of the combination space shuttle orbiter and ferry vehicle

Subsonic forced-oscillation tests of a 0.015 scale model of the space shuttle orbiter/747 ferry vehicle were conducted in the Langley high speed 7- by 10-foot tunnel at Mach numbers of 0.2, 0.4, and 0.5 for angles of attack up to 12 deg. Tests were made of the basic 747 airplane, of the modified 747 (tip fins and struts added), of the ferry configuration, (747 plus orbiter at an incidence angle of 3 deg), and of the approach and landing test configuration (747 plus orbiter at an incidence angle of 6 deg)

Supersonic dynamic stability characteristics of a space shuttle orbiter

Supersonic forced-oscillation tests of a 0.0165-scale model of a modified 089B Rockwell International shuttle orbiter were conducted in a wind tunnel for several configurations over a Mach range from 1.6 to 4.63. The tests covered angles of attack up to 30 deg. The period and damping of the basic unaugmented vehicle were calculated along the entry trajectory using the measured damping results. Some parameter analysis was made with the measured dynamic derivatives. Photographs of the test configurations and test equipment are shown

Subsonic and transonic dynamic stability characteristics of a space shuttle orbiter

Subsonic and transonic forced oscillation tests of a 0.0165-scale model of a modified 089B space shuttle orbiter were made in the Langley 8-foot transonic pressure tunnel. The period and damping of the basic unaugmented vehicle were calculated along the entry trajectory utilizing these measured dynamic data. Some parameter analyses were made with the measured dynamic derivatives

Supersonic dynamic stability derivatives of a modified 089B shuttle orbiter

An experimental test program was conducted to measure the dynamic stability derivatives of a modified 089B shuttle orbiter. Supersonic forced oscillation tests were conducted in the Langley Unitary Plan Wind Tunnel over a range of Mach numbers from 1.6 to 4.63 for angles of attack up to 30 deg. The data were measured at the model resonant frequency with pitch and yaw amplitudes of 1 deg and a roll amplitude of 2.5 deg

Subsonic and transonic dynamic stability characteristics of the space shuttle launch vehicle

An investigation has been conducted to determine the subsonic and transonic dynamic stability characteristics of a 0.015 scale model of the space shuttle launch vehicle. These tests were conducted in the Langley 8-foot transonic pressure tunnel over a Mach number range from 0.3 to 1.2. Forced oscillation equipment was used to determine the damping characteristics of several configurations about all three axes. The test results show that the model exhibited positive damping in pitch except at the highest Mach number (1.2) where there was a region of negative damping at 2 deg angle of attack. The yawing oscillation tests show that the model exhibited nonlinearities and negative damping at Mach numbers of 0.3 and 0.6. The model exhibited positive roll damping throughout the test angle of attack and Mach range

Supersonic dynamic-stability derivatives of the space shuttle launch vehicle

An investigation was made to determine the dynamic stability characteristics of a 0.015-scale model of the space shuttle launch vehicle at supersonic speeds. These tests were made at angles of attack from -10 deg to 10 deg at Mach numbers of 2.00, 2.86, 3.96, and 4.63. The complete launch vehicle, consisting of the orbiter, external tank, and solid rocket boosters, has positive damping in pitch, roll, and yaw over the angle-of-attack and Mach number range. The orbiter external tank configuration has a region of negative angles pitch damping for small negative of attack at a Mach number of 2.00. At all other test conditions, the orbiter external tank configuration has positive damping about all three axes

Transonic static and dynamic stability characteristics of a finned projectile configuration

Static and dynamic stability tests were made of a finned projectile configuration with the aft-mounted fins arranged in a cruciform pattern. The tests were made at free stream Mach numbers of 0.7, 0.9, 1.1, and 1.2 in the Langley 8-foot transonic pressure tunnel. Some of the parameters measured during the tests were lift, drag, pitching moment, pitch damping, and roll damping. Configurations tested included the body with undeflected fins, the body with various fin deflections for control, and the body with fins removed. Theoretical estimates of the stability derivatives were made for the fins on configuration

Network inference analysis identifies an APRR2-like gene linked to pigment accumulation in tomato and pepper fruits

Carotenoids represent some of the most important secondary metabolites in the human diet, and tomato (Solanum lycopersicum) is a rich source of these health-promoting compounds. In this work, a novel and fruit-related regulator of pigment accumulation in tomato has been identified by artificial neural network inference analysis and its function validated in transgenic plants. A tomato fruit gene regulatory network was generated using artificial neural network inference analysis and transcription factor gene expression profiles derived from fruits sampled at various points during development and ripening. One of the transcription factor gene expression profiles with a sequence related to an Arabidopsis (Arabidopsis thaliana) ARABIDOPSIS PSEUDO RESPONSE REGULATOR2-LIKE gene (APRR2-Like) was up-regulated at the breaker stage in wild-type tomato fruits and, when overexpressed in transgenic lines, increased plastid number, area, and pigment content, enhancing the levels of chlorophyll in immature unripe fruits and carotenoids in red ripe fruits. Analysis of the transcriptome of transgenic lines overexpressing the tomato APPR2-Like gene revealed up-regulation of several ripening-related genes in the overexpression lines, providing a link between the expression of this tomato gene and the ripening process. A putative ortholog of the tomato APPR2-Like gene in sweet pepper (Capsicum annuum) was associated with pigment accumulation in fruit tissues. We conclude that the function of this gene is conserved across taxa and that it encodes a protein that has an important role in ripening

Low-Speed Wind Tunnel Tests of Two Waverider Configuration Models

A definitive measurement of the low-speed flight characteristics of waverider-based aircraft is required to augment the overall design database for this important class of vehicles which have great potential for efficient high-speed flight. Two separate waverider-derived vehicles were tested; one in the 14- by 22-Foot Tunnel and the other in the 12-Foot Low Speed Tunnel at Langley Research Center. These tests provided measurements of moments and forces about all three axes, control effectiveness, flow field characteristics and the effects of configuration changes. The results of these tunnel tests are summarized and the subsonic aerodynamic characteristics of the two configurations are shown

From the Singular to the Plural: Exploring Diversities in Contemporary Childhoods in sub-Saharan Africa

The challenges that sub-Saharan Africa has faced in the post-colonial period have come to characterise the way the region is perceived. These narratives are especially evident in the various ways children’s lives are discussed, leading to a particular focus on childhoods in difficult circumstances or at the margins. This has eclipsed the mundanities of everyday life for many children whose lives are not characterised by ‘lacks’. This article seeks to move beyond an overwhelming focus on childhoods defined by what they lack by illustrating the multitude of childhoods which exist in the continent