(The total budget for the mission was estimated at 4,200 million rubles.) As expected, NPO Lavochkin, the prime developer of the nation's planetary probes, was awarded the contract.
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Since the FST was to be the first wind tunnel constructed with an elliptic throat and two drive propellers mounted side-by-side, the designers requested that a 1/15-scale model of the FST be constructed for studies of the flow circuit and guidance in the shaping of the tunnel lines and airflow turning. The request was approved, but it was noted that the NACA did not have sufficient shop space for construction of the model tunnel. Instead, management suggested that the model be built outdoors with a protective roof. Construction of the proceeded in a vacant area between two NACA power plant buildings behind the NACA administration building in 1929 using a lumber framework and a tarpaulin-covered roof. After a highly successful test program which provided vital design information, the model tunnel was moved to the FST building after the full-scale article was constructed.
Brave New World : Chapter One by Aldous ..
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A , the dimension (physical height) of an average man, and the human population of Earth (red, blue/white, & white respectively).
A graphic of the indicating which of the planets the message is coming from (yellow).
A graphic of the Arecibo radio telescope and the dimension (the physical diameter) of the transmitting antenna dish (purple, white, & blue).
Since it will take nearly 25,000 years for the message to reach its intended destination (and an additional 25,000 years for any reply), the message is viewed as a demonstration of human technological achievement, versus a real attempt to enter into a conversation with extraterrestrials.
第34章 Chapter One(4)-美妙的新世界在线阅读-阿道司· …
In the 1970s Langley conducted a major inspection and rehab of the FST uncovering alarming fatigue cracks and evidence of major vibratory issues within the mounting structures of both drive motors. The non-symmetric airflow in the tunnel (both propellers rotated in the same direction) was identified as a major factor causing the problem, and Langley requested that NASA Headquarters attempt to have the model tunnel returned to Langley for additional studies of altering the flow properties in the FST. However, return of the tunnel was resisted (the problem actually was discussed at levels as high as the Secretary of State Henry Kissinger) and the tunnel remained in Portugal. NASA proceeded to have a second model tunnel constructed under contract in Canada, and that tunnel was located in the hangar annex of the FST and used to evaluate many structural modifications to mitigate the flow-induced structural problems. Several modifications to the FST came from the model investigation including large guide vanes located around the periphery of the inlet of the tunnel exit cone.
The National Harm Service morphing into the Mental …
Work on the FST proceeded rapidly, and it was completed and ready for operation in May 1931, when it was the NACA centerpiece of the Sixth Annual Aircraft Engineering Conference. The largest wind tunnel in the world at that time, the FST had a unique design, with the building’s steel framework visible on the exterior of the building. The enormous facility measured 434 feet in length, 222 feet in width, and 97 feet in height, and immediately became a recognizable landmark at Langley. The semi-elliptical test section measured 30 feet high by 60 feet wide with an open jet (that is, no walls immediately adjacent to the test section) and allowed the installation of aircraft with wingspans up to 40 feet. The tunnel was powered by two 35 feet 5 inch diameter propellers, each driven by a 4,000-horsepower electric motor, which could circulate air through the test section at speeds between 25 and 118 mph. The air circuit was of the double-return type, in which the airflow from the propellers was split right and left into two streams, doubling back between the test section and the building’s walls, then reuniting before entering the throat of the test section. Extensive tuning of airfoil-shaped turning vanes in the tunnel circuit resulted in satisfactory flow properties in the test section. In addition to testing full-scale aircraft the FST had considerably lower turbulence than the VDT.