NASA’s Lewis Research Center conducted extensive research programs in the 1960s and 1970s to develop systems that provide electrical power in space. One system, the Brayton cycle engine, converted solar thermal energy into electrical power. This system operated on a closed-loop Brayton thermodynamic cycle. The Brayton system relied on this large mirror to collect radiation from the sun. The mirror concentrated the Sun's rays on a heat storage receiver which warmed the Brayton system’s working fluid, a helium-xenon gas mixture. The heated fluid powered the system’s generator which produced power.     In the mid-1960s Lewis researchers constructed this 30-foot diameter prototype of a parabolic solar mirror for the Brayton cycle system. The mirror had to be rigid, impervious to micrometeorite strikes, and lightweight. This mirror was comprised of twelve 1-inch thick magnesium plate sections that were coated with aluminum. The mirror could be compactly broken into its sections for launch.
Solar Collector Mirror for Brayton Power System
One of NASA's unmanned, remotely controlled aircraft, the Perseus B, is seen here before its first flight at the Dryden Flight Research Center, Edwards, California.
Perseus B on lakebed before first flight
National Advisory Committee for Aeronautics (NACA) design engineers added the Icing Research Tunnel to the new Aircraft Engine Research Laboratory’s original layout to take advantage of the massive refrigeration system being constructed for the Altitude Wind Tunnel. The Icing Research Tunnel was built to study the formation of ice on aircraft surfaces and methods of preventing or eradicating that ice. Ice buildup adds extra weight, effects aerodynamics, and sometimes blocks airflow through engines.         The Icing Research Tunnel is a closed-loop atmospheric wind tunnel with a 6- by 9-foot test section. The tunnel can produce speeds up to 300 miles per hour and temperatures from about 30 to –45⁰ F. Initially the tunnel used a spray bar system to introduce moisture into the airstream. NACA engineers struggled for nearly 10 years to perfect the spray system.    The Icing Research Tunnel began testing in June of 1944. Initial testing, seen in this photograph, studied ice accumulation on propellers of a military aircraft. NACA reserach also produced a protected air scoop for the C–46 transport aircraft. A large number of C–46 aircraft were lost due to icing while flying supply runs over the Himalayas during World War II.
Early Testing in the Icing Research Tunnel
Set up of a Brayton Cycle Power System test in the Space Power Facility’s massive vacuum chamber at the National Aeronautics and Space Administration’s (NASA) Plum Brook Station in Sandusky, Ohio. The $28.4-million facility, which began operations in 1969, is the largest high vacuum chamber ever built. The chamber is 100 feet in diameter and 120 feet high. It can produce a vacuum deep enough to simulate the conditions at 300 miles altitude.  The Space Power Facility was originally designed to test nuclear-power sources for spacecraft, but it was never used for that purpose.   The Space Power Facility was first used to test a 15 to 20-kilowatt Brayton Cycle Power System for space applications. Three different methods of simulating solar heat were employed during the tests.    Lewis researchers studied the Brayton power system extensively in the 1960s and 1970s. The Brayton engine converted solar thermal energy into electrical power. The system operated on a closed-loop Brayton thermodynamic cycle with a helium-xenon gas mixture as its working fluid. A space radiator was designed to serve as the system’s waste heat rejecter. The radiator was later installed in the vacuum chamber and tested in a simulated space environment to determine its effect on the power conversion system. The Brayton system was subjected to simulated orbits with 62 minutes of sun and 34 minutes of shade.
Brayton Cycle Power System in the Space Power Facility
Technicians set up test hardware inside the test section of the Icing Research Tunnel at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The Icing Research Tunnel was built in the early 1940s to study the formation of ice on aircraft surfaces and develop methods of preventing or eradicating that ice. Ice buildup is dangerous because it adds extra weight, effects aerodynamics, and sometimes blocks air flow through engines.  The Icing Research Tunnel is a closed-loop atmospheric wind tunnel with a 6- by 9-foot test section. The tunnel can produce speeds up to 300 miles per hour and temperatures from 30 to -45 °F. NACA engineers struggled initially to perfect a spray bar system to introduce moisture into the airstream.    The tunnel was shut down in the late 1950s as the center focused its energy exclusively on space. Industrial customers began using the tunnel sporadically, then steadily, in the 1960s. Boeing, Aerojet, Lockheed, Sikorsky, Beech and others ran tests during the 1960s. Boeing analyzed engine inlets for the CH-47 Chinook, CH-46 (Sea Knight) and CH-113. This photograph was taken during a series of 100 ice-phobic coatings for the Federal Aviation Administration. They found that many of the coatings reduced ice adhesion to the test sample, but they could not be used for aircraft applications.
Setup in the Icing Research Tunnel Test Section
A National Advisory Committee for Aeronautics (NACA) researcher measures the ice thickness on a landing antenna model in the Icing Research Tunnel at the Aircraft Engine Research Laboratory. NACA design engineers added the Icing Research Tunnel to the original layout of the new Aircraft Engine Research Laboratory to take advantage of the massive refrigeration system being built for the Altitude Wind Tunnel. The Icing Research Tunnel was built to study the formation of ice on aircraft surfaces and methods of preventing or eradicating that ice. Ice buildup adds extra weight, effects aerodynamics, and sometimes blocks air flow through engines.       The Icing Research Tunnel is a closed-loop atmospheric wind tunnel with a 6- by 9-foot test section. Carrier Corporation refrigeration equipment reduced the internal air temperature to -45 degrees F and a spray bar system injected water droplets into the air stream. The 24-foot diameter drive fan, seen in this photograph, created air flows velocities up to 400 miles per hour.    The Icing Research Tunnel began testing in June of 1944. Early testing, seen in this photograph, studied ice accumulation on propellers and antenna of a military aircraft. The Icing Research Tunnel’s designers, however, struggled to develop a realistic spray system since they did not have access to data on the size of naturally occurring water droplets. The system would have to generate small droplets, distribute them uniformly throughout the airstream, and resist freezing and blockage. For five years a variety of different designs were painstakingly developed and tested before the system was perfected.
Engineer Measures Ice Formation on an Instrument Antenna Model
CAPE CANAVERAL, Fla. – During a free-flight test of the Project Morpheus vehicle at the Shuttle Landing Facility at NASA’s Kennedy Space Center in Florida, the vehicle lifted off the ground and then experienced a hardware component failure, which prevented it from maintaining stable flight. No one was injured and the resulting fire was extinguished by Kennedy fire personnel. Engineers are looking into the test data and the agency will release information as it becomes available. Failures such as these were anticipated prior to the test, and are part of the development process for any complex spaceflight hardware.    Testing of the prototype lander had been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free-flight test at Kennedy Space Center. Morpheus was manufactured and assembled at JSC and Armadillo Aerospace. Morpheus is large enough to carry 1,100 pounds of cargo to the moon – for example, a humanoid robot, a small rover, or a small laboratory to convert moon dust into oxygen. The primary focus of the test is to demonstrate an integrated propulsion and guidance, navigation and control system that can fly a lunar descent profile to exercise the Autonomous Landing and Hazard Avoidance Technology, or ALHAT, safe landing sensors and closed-loop flight control. For more information on Project Morpheus, visit http://morpheuslander.jsc.nasa.gov/. Photo credit: NASA
KSC-2012-4346
CAPE CANAVERAL, Fla. – During a free-flight test of the Project Morpheus vehicle at the Shuttle Landing Facility at NASA’s Kennedy Space Center in Florida, the vehicle lifted off the ground and then experienced a hardware component failure, which prevented it from maintaining stable flight. Engineers are looking into the test data and the agency will release information as it becomes available. Failures such as these were anticipated prior to the test, and are part of the development process for any complex spaceflight hardware.    Testing of the prototype lander had been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free-flight test at Kennedy Space Center. Morpheus was manufactured and assembled at JSC and Armadillo Aerospace. Morpheus is large enough to carry 1,100 pounds of cargo to the moon – for example, a humanoid robot, a small rover, or a small laboratory to convert moon dust into oxygen. The primary focus of the test is to demonstrate an integrated propulsion and guidance, navigation and control system that can fly a lunar descent profile to exercise the Autonomous Landing and Hazard Avoidance Technology, or ALHAT, safe landing sensors and closed-loop flight control. For more information on Project Morpheus, visit http://morpheuslander.jsc.nasa.gov/. Photo credit: NASA
KSC-2012-4344
CAPE CANAVERAL, Fla. – During a free-flight test of the Project Morpheus vehicle at the Shuttle Landing Facility at NASA’s Kennedy Space Center in Florida, the vehicle lifted off the ground and then experienced a hardware component failure, which prevented it from maintaining stable flight. No one was injured and the resulting fire was extinguished by Kennedy fire personnel. Engineers are looking into the test data and the agency will release information as it becomes available. Failures such as these were anticipated prior to the test, and are part of the development process for any complex spaceflight hardware.    Testing of the prototype lander had been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free-flight test at Kennedy Space Center. Morpheus was manufactured and assembled at JSC and Armadillo Aerospace. Morpheus is large enough to carry 1,100 pounds of cargo to the moon – for example, a humanoid robot, a small rover, or a small laboratory to convert moon dust into oxygen. The primary focus of the test is to demonstrate an integrated propulsion and guidance, navigation and control system that can fly a lunar descent profile to exercise the Autonomous Landing and Hazard Avoidance Technology, or ALHAT, safe landing sensors and closed-loop flight control. For more information on Project Morpheus, visit http://morpheuslander.jsc.nasa.gov/. Photo credit: NASA
KSC-2012-4345
A Bell P-39 Airacobra in the NACA Aircraft Engine Research Laboratory’s Icing Research Tunnel for a propeller deicing study. The tunnel, which began operation in June 1944, was built to study the formation of ice on aircraft surfaces and methods of preventing or eradicating that ice. Ice buildup adds extra weight to aircraft, effects aerodynamics, and sometimes blocks airflow through engines.       NACA design engineers added the Icing Research Tunnel to the new AERL’s original layout to take advantage of the massive refrigeration system being constructed for the Altitude Wind Tunnel. The Icing Research Tunnel is a closed-loop atmospheric wind tunnel with a 6- by 9-foot test section. The tunnel can produce speeds up to 300 miles per hour and temperatures from about 30 to -45⁰ F.   During World War II AERL researchers analyzed different ice protection systems for propeller, engine inlets, antennae, and wings in the icing tunnel. The P-39 was a vital low-altitude pursuit aircraft of the US during the war. NACA investigators investigated several methods of preventing ice buildup on the P-39’s propeller, including the use of internal and external electrical heaters, alcohol, and hot gases. They found that continual heating of the blades expended more energy than the aircraft could supply, so studies focused on intermittent heating. The results of the wind tunnel investigations were then compared to actual flight tests on aircraft.
Vultee YA–31C Vengeance at the NACA
A Bell P-39 Airacobra in the NACA Aircraft Engine Research Laboratory’s Icing Research Tunnel for a propeller deicing study. The tunnel, which began operation in June 1944, was built to study the formation of ice on aircraft surfaces and methods of preventing or eradicating that ice. Ice buildup adds extra weight to aircraft, effects aerodynamics, and sometimes blocks airflow through engines.     NACA design engineers added the Icing Research Tunnel to the new AERL’s original layout to take advantage of the massive refrigeration system being constructed for the Altitude Wind Tunnel. The Icing Research Tunnel is a closed-loop atmospheric wind tunnel with a 6- by 9-foot test section. The tunnel can produce speeds up to 300 miles per hour and temperatures from about 30 to –45⁰ F.  During World War II AERL researchers analyzed different ice protection systems for propeller, engine inlets, antennae, and wings in the icing tunnel. The P-39 was a vital low-altitude pursuit aircraft of the US during the war. NACA investigators investigated several methods of preventing ice buildup on the P-39’s propeller, including the use of internal and external electrical heaters, alcohol, and hot gases. They found that continual heating of the blades expended more energy than the aircraft could supply, so studies focused on intermittent heating. The results of the wind tunnel investigations were then compared to actual flight tests on aircraft.
Bell P-39 in the Icing Research Tunnel