Dryden's 60 Years of Flight Research

the speed of aircraft increased dramatically during World War two after the war the quest for speed continued but was stymied by a sound barrier an aerodynamic phenomenon that resulted in loss of aircraft and pilots the wind tunnels at that time could not provide accurate data near Mach 1 the only means available to understand the unknowns facing pilots at transonic and supersonic speeds was to build specialized research aircraft with enough structural strength to withstand the unknown forces with its ideal flying weather the Muroc Army Airfield in Southern California was the perfect location for operating these research aircraft Rogers dry lake with an area of 44 square mile served as a runway that stretched for miles in any direction in September of 1946 the first group of engineers from the National Advisory Committee for Aeronautics or NACA arrived at Muroc they were to assist the Army Air Force in a supersonic flight program involving the xs-1 their new home was much different than the one they had left in Virginia the facilities were as rugged as the desert landscape initially named NACA Muroc flight test unit the staff had a single hangar and leaned two offices while housing consisted of wartime barracks some personnel left due to the harsh conditions but those who stayed established a tradition of innovation and creativity the Bell xs-1 its fuselage patterned on the lines of a 50 caliber machine gun bullet was designed to fly at speeds in excess of Mach 1 the Air Force with NACA support conducted an accelerated test program with the first x1 with the goal of quickly reaching Mach 1 the rocket-powered xs-1 later redesignate 'add x1 was carried aloft by a modified b-29 as the b-29 climbed to altitude the excess one pilot entered the cockpit on the historic day of October 14 1947 captain Charles Chuck Yeager seated in the excess one as it dropped away from the b-29 lit the rocket engines as the plane accelerated it pulled away from the p80 chase plane trailing a long white contrail as the speed increased a Mach meter needle past 0.98 then suddenly jumped off scale signifying supersonic flight captain Yeager had become the first person to break through the sound barrier piloting the XS 1/2 Mach 1.06 naca flu ii x1 in a more cautious step-by-step build up program Herbert Hoover not the 31st President became the first civilian NACA pilot to reach Mach 1 on March 4 1948 originally painted Orange the ex ones were repainted white for better tracking visibility against the blue sky this remains the case even today for most research aircraft the x1 program laid the foundation for NACA x' and later NASA's flight research other aircraft exploring the transonic region of flight included the Douglas d558 phase 1 sky streaked and phase 2 skyrocket in a joint NACA Navy program the phase 1 was a conventional 1940s design with a turbojet engine to explore the transonic regime vortex generators seen now on many military and commercial aircraft were first developed on the d558 phase 1 the d558 phase 2 in contrast was a swept wing aircraft designed to explore supersonic flight though turbojet turbo jet and rocket and rocket only versions were built the rocket only version of the d558 phase 2 launched from the b-29 was much more productive gathering supersonic research data though it was against NAC a policy to set speed or altitude records Scott Crossfield convinced management to attempt an assault on Mach 2 with a d558 phase 2 rocket-powered skyrocket in preparation for its record flight at the edge of its envelope the sky rocket was fitted with engine nozzle extensions for more thrust skin was waxed to reduce drag and the aircraft chill to allow more fuel to be carried on the cold winter morning of November 20 1953 after the sky rocket dropped from the b-29 Rossville lit the rockets and climbed to 62 thousand feet flying a perfect flight plan he piloted the d558 phase 2 to its maximum speed of Mach two point zero zero five and became the first man to exceed twice the speed of sound versions of the x1 continued to perform high-speed flight research the most notable one now sits on a post in front of the main building at Dryden it is the x1 II it was modified in-house from the first NACA x1 to conduct research on very thin wings at high speeds it first flew in December 1955 and continued mach-2 flights to the end of 1958 while the rocket-powered aircraft attracted much of the public's attention these were not the only research vehicles being tested in the 1950s some of these revolutionary vehicles looked rather strange even by today's standards one such example was the douglas x3 stiletto which was developed to test very thin low aspect ratio wings at high speeds however the planned high thrust jet engines did not materialize it was severely underpowered with the substitute engines it was difficult to control and could only reach supersonic speed by putting the aircraft in a deep dive although not entirely successful the x3 did make significant contributions similar wings were used successfully on the f-104 the x3 was one of the first aircraft to use titanium its incredible high landing speed of 260 knots also necessitated the development of high speed aircraft tires the Northrop x4 tested a semi tail as swept-back wing configuration engineers hoped that eliminating the horizontal stabilizers would ease control problems at transonic speeds but at speeds approaching Mach 1 the aircraft handled poorly it was likened to driving over a washboard Road this configuration would prove to be impractical until the arrival of digital flight computers 20 years later the bell x5 was designed to test the feasibility of changing the sweep angle of an aircraft's wings in flight such a capability would give an aircraft good low-speed control with the wings extended while at high speeds the wings could be swept back to reduce drag an extensive flight test program with the x5 showed these predictions were justified and the concept has since been used successfully on aircraft like the f-111 f-14 b1 and others this first decade of Flight Research at Muroc was an exciting period with many milestones achieved and signaled the bright future to come as the quest for speed and altitude continued the Air Force Navy and the NACA later NASA contracted with North American aviation to build a new vehicle this new vehicle the x-15 would probe the hypersonic speed regime that is faster than Mach 5 and perform flight research at the edges of the Earth's atmosphere to perform its mission the x-15 structure was made from a nickel chrome alloy called inconel X it could retain its strength up to a cherry-red 1,200 degrees Fahrenheit a temperature that would melt aluminum and make stainless steel useless the x-15 was powered by an XLR 99 variable thrust rocket engine with a thrust range from twenty eight thousand to fifty seven thousand pounds before each flight the pilots trained 8 to 10 hours in a ground-based simulator the x-15 s flight envelope demanded precise control during all phases of flight the powered phase the flight out of the atmosphere and especially the re-entry the pilots trained for the multitude of possible malfunctions of the rocket engine systems and displays the appreciation of the ground-based flight simulator was fully realized first in the x-15 program a flight began with the pilot climbing into the x-15 attached under the wing of the b-52 on the ramp the b-52 then taxied out and took off slowly climbing to 45,000 feet heading for the northeastern corner of Nevada once there the b-52 turned back toward Edwards and launched the x-15 once clear of the b-52 the pilot lit the rocket engine and began his particular flight profile climbed for altitude for instance or a speed run in spite of launching in northeastern Nevada the x-15 s flight to Rogers dry lake lasted an average of just 10 minutes the engine consumed the entire fuel supply in less than two minutes after which the airplane was a high-speed glider with a lift-to-drag ratio of about 4 to 1 the pilot was busy the entire flight and had very little time to enjoy the scenery things happen fast at Mach 5 plus and this was no airplane to fall behind on maintaining a proper angle of attack was critical if the pilot was to reach the designated altitude under an overshooting were startling ly easy and both had a dramatic effect on the final altitude reached by the aircraft the bottom portion of the ventral fin the vertical stabilizer underneath the aft portion of the fuselage was too tall to permit landing with it attached so it was jettisoned moments before landing then retrieved and used again the x-15 had no brakes for landing just two skids that popped out at the aft end of the fuselage and a nose gear with two wheels that was not steerable the x-15 came down quickly and its pilot had only one chance at landing as do shuttle pilots today you for its record speed flight the x-15 was fitted with two external propellant tanks which could be jettisoned and covered with a silicon ablative coating painted white unlike the shuttle tiles the ablative absorbed the additional heating from the high-speed by charing rather than insulating even then surprisingly shock impingement around a dummy ramjet on the lower ventral tail cause some serious local damage to the skins the ablative coating proved to be impractical for a reusable reentry vehicle since the old coating would have to be stripped and a new coating reapplied for each flight with flight starting in 1959 and extending to 1968 it was and still is considered the most successful of all experimental research aircraft the x-15 program added to the historic foundation of aerodynamics sometimes measurably often intangibly in ways that were not imagined it pushed the piloted records to an altitude of 67 miles and speed to Mach 6.78 of the 12 X 15 pilots earned their astronaut wings the x-15 provided much new insight into the once-feared region of flight outside the atmosphere it also gave engineers critical data on the unique challenge of reentry re-entry compounds the effects of aerodynamics and spaceflight maneuvering and proved to be more demanding of both pilot and aircraft than anything encountered before many of the mysteries of re-entry flight were solved by the x-15 in sharp contrast to the high speeds and altitudes of the x-15 a strange-looking vehicle appeared at the center the low-speed m2 f1 a lifting body vehicle had no wings and resembled a bathtub a Dryden engineer Dale Reid sought to validate this new reentry concept with a manned research aircraft rather than using a ballistic reentry trajectory like a Mercury Gemini or Apollo capsule with very limited maneuvering range a lifting body vehicle had an estimated landing footprint the size of California the tubby vehicle shape was taken from reentry lifting body shapes that were being tested at the NASA Ames Research Center after seeing Reid's two foot model fly center director Paul Bickle authorized an in-house effort to build the man m2 f1 in the spring of 1963 Milt Thompson made the first flight of the m2 f1 towed behind a hot rod Pontiac Catalina convertible later an R for D Navy dc-3 was used for tows to higher altitudes flights released from behind the r4d at 12,000 feet lasted just two minutes until landing the m2 f1 would lead to bigger things in the future if the m2 f1 was strange the lunar landing research vehicle was out of this world during the 1960's NASA had embarked on a journey to the moon the Apollo program's mission was to land men on the moon and return them safely to earth no one on the Apollo program one of the first lunar landing with its high pilot workload in psychological stress to be the first time an astronaut team flew a lunar landing descent profile to help train astronauts for this difficult task Dryden engineers Don bellman and Jean Matranga along with Bell aerospace conceived of an in-flight simulator to train the astronauts it became known as the lunar landing research vehicle LL RV the LL RV was a free flying simulator held aloft by a turbofan jet simulating the moon's gravity and maneuvered with hydrogen peroxide thrusters first delivered in late 1964 the LL RV was flown by the Dryden research pilots Joe Walker Don Malek and the Army's Jack kluever during that time the team made significant modifications to the craft some to better mimic the lunar module in its layout others to make the vehicle safer or more capable perhaps most significant of all the vehicle was a pure fly-by-wire craft controlled by three analog computers with no mechanical backup during its 198 flights at Edwards it had flown as long as 9 and 1/2 minutes and reached a maximum altitude of nearly 800 feet it was then turned over to Houston in December of 1966 for training the Apollo astronauts propeller or forward as they say the rest is history on July 20th 1969 former Dryden Center pilot Neil Armstrong set the Apollo lunar module down on the moon the eagle has landed the success of the m2 f1 encouraged NASA headquarters to approve development of heavy weight lifting bodies which would be launched from the b-52 and powered by an XLR 11 rocket engine although the lightweight m2 f1 could simulate the low lift-to-drag ratio it could not simulate the high speeds that a heavy weight vehicle could achieve the initial program involved building two different vehicles the m2 f2 proposed by NASA Ames Research Center and the HL 10 proposed by NASA Langley Research Center the first flight of the m2 f2 occurred on July 12 1966 with NASA pilot Milt Thompson at the controls from the start it was apparent that the m2 f2 at handling problems several times the aircraft rolled back and forth violently as it descended each time however the pilot was able to regain control despite these problems flights continued through the remainder of 1966 and into the new year while the m2 f2 was cautiously expanding its envelope NASA pilot Bruce Peterson piloted the first flight of the HL 10 in December of 1966 Peterson discovered that the vehicle was barely flyable only by keeping the HL 10 speed up was he able to maintain control this first flight in the words of Langley engineers once again demonstrated the value of flight tests as proof of concept the vehicle was grounded while engineers at NASA Langley and Dryden could come up with a fix although the HL 10 was grounded the m2f 2 program pressed on other pilots join the program in May of 1967 during the 17th flight of the m2 f2 the handling problems came to a head during a violent crash the m2 f2 was significantly damaged in the pilot Bruce Peterson was seriously injured Peterson eventually lost an eye to the accident but otherwise recovered this accident became the opening scene for the 1970s hit TV series the Six Million Dollar Man following the accident the vehicle was rebuilt in-house by Dryden technicians and renamed the m2 f3 the most significant change was the addition of a center fin which greatly stabilized the aircraft at low speeds and solved the recurring problem of poor lateral control analysis of flight and wind tunnel data from the first HL 10:00 flight suggested flow separation on the outboard fins after the leading edges of the outboard fins were modified the HL 10 made its second glide flight in March of nineteen sixty eight and now handled as well as an f-104 in February of 1970 Air Force pilot Peter ho took the HL 10 to a speed of mach 1.8 6 the highest speed reached by any piloted lifting body that same month NASA pilot bill Dana took the HL 10 to 90,000 30 feet the highest of any heavy weight lifting body another lifting body x24 a was sponsored by the air force and joined the flight test program first flown in April of 1969 by Air Force pilot Gerald Gentry the vehicle resembled a potato with three fins its shape would be later used in the design of the x-38 crew return vehicle the final lifting body tested at Edwards was the x24 bee this aircraft was actually the original x24 a airframe but with a sleek new outer shell grafted on the once potato-shaped a vehicle now looked like a flatiron with a long nose and flat underside this design gave the x24 be a much better lift to drag ratio the initial glide flight was made in August of 1973 with NASA pilot John manky at the controls the earlier lifting bodies and the x-15 it all landed on the lakebed partially due to the lack of nosewheel steering with which the ex 24b was now equipped in August of 1975 on its 27th flight Menke made a precise landing on the Edwards concrete runway demonstrating the ability of an unpowered reentry vehicle to make a pinpoint landing bill Dana made the final powered ex 24b flight in September of 1975 which was the last manned rocket plane flight made at Dryden in the 1960s the US had a supersonic transport SST program in competition with the British French Concorde SST Dryden contributed to that program through its supersonic flight research utilizing the xb-70 and the yf-12a the xb-70 was originally conceived as a Mach 3 strategic bomber with an operational altitude of 70,000 feet only to experimental prototypes have been built by the time the Defense Department cancelled the program the large size of the xb-70 made it an ideal testbed for joint NASA Air Force SST research after a tragic accident destroyed the xb-70 - the program proceeded with the less capable xb-70 one though limited to Mach 2.5 it yielded data on a number of issues facing SST designers including aircraft noise operational problems control system design sonic booms high-altitude turbulence and correlation of wind tunnel and flight data in a similar fashion the lockheed yf-12 a black birds ability to sustain Mach 3 cruise speeds allowed NASA to expand its research capabilities and contribute to the SST program the yf-12 Flight Research Program generated supersonic data on aerodynamics propulsion controls structures and subsystems it also provided critical data in other areas such as upper atmosphere physics noise tests and measurements materials and handling qualities one particularly interesting experiment focused on heat transfer and exposed and insulated and chilled hollow cylinder instantly to Mach three flight conditions yf-12 flight research data was complemented by a series of Windtunnel tests laboratory experiments and analyses as a result the combined ground and flight research generated vast amounts of information that was later incorporated into supersonic aircraft design the first slide of the F 8 digital fly-by-wire aircraft in May of 1972 by NASA pilot Giri career assured in a radical new flight control concept until the conception of the fa digital fly-by-wire vehicle mechanical systems which range from steel control cables to hydraulics had been used to transmit a pilot stick and rudder inputs to the control surfaces although some electronic fly-by-wire systems had been flight tested these aircraft still retain the mechanical links as backup the lunar landing research vehicle being the exception by the late 1960s digital computers have become more available and offered a lighter more capable and flexible fly-by-wire system Brydon engineers proposed such a digital system be developed and flight tested the computer initially used was from the Apollo 15 command module digital computer but was later replaced with 380 101 general purpose digital computers these were state-of-the-art computers in the mid-1970s each had 32k of memory operated at 0.48 megahertz weighed nearly 48 pounds and cost $130,000 this system demonstrated fault tolerance by continuing normal operation after certain computer failures the amazing contributions of the revolutionary f8 digital fly-by-wire program were quick to follow today fly-by-wire is used in almost every modern aircraft including fighters bombers transports and airliners another f8 was also flying at Dryden during this time the supercritical wing aircraft the supercritical wing grew out of Richard Wickham's innovative research at the Langley Research Center the wing featured a flattened top surface with a downward curve at the trailing edge the flattened top reduced the tendency to generate shock waves and the downward curve at the trailing edge restored the lift loss by flattening the top the first flight of the f8 supercritical wing was made in March of 1971 by NASA pilot Tom McMurtry the flight test data confirmed Windtunnel results that the wing had lower drag than conventional wings at speeds just below Mach 1 the reduced high-speed drag offered increased cruise speed improved fuel efficiency and a longer range in the decades since supercritical wings have appeared not only on airliners but fighters heavy transports and business jets the third decade was a busy period with long lasting results the lifting body vehicles made great contributions to what would become the Space Shuttle both the digital fly-by-wire and supercritical wing research opened up a new era in aircraft design most modern aircraft in the sky today utilize some element of design that was pioneered at Dryden during this exciting period of flight research just as the x-15 defined the second decade at Dryden the Space Shuttle defined the center's role within NASA two decades later the approach and landing tests of the prototype orbiter enterprise brought a level of attention to Dryden that exceeded even that of the x-15 era the enterprise was to be launched from the back of a modified 747 airliner with the orbiter gliding to a landing the approach and landing tests or alt would validate the vehicles low-speed aerodynamics and systems including the orbiters fly-by-wire control system early in the morning of august 12 1977 tens of thousands of visitors streamed onto Edwards Air Force Base and lined the east shore of Rogers dry lake to view the first free flight of the shuttle after-tax saying from the mate demate device and taking off from the main runway the orbiter 747 combination climbed to 30,000 feet with the orbiter on its back the 747 went into a slight dive and the enterprise gently separated as the 747 Bank to the left the Enterprise Bank right and glided to a successful landing on Rogers dry lakebed two more free flights were made in the following months each one with the aerodynamic fairing installed on the aft end of the enterprise intended for use during ferry flights to Kennedy on the fourth flight the orbiters fairing was removed and the descent was steeper and faster than on earlier flights the fifth and final free flight in October 1977 was to demonstrate a safe landing on the Edwards main runway instead of the lake bed each side of the runway was lined with employees and guests of Dryden for a closer view the release and glide were uneventful but his Enterprise neared the runway a problem surfaced the fly-by-wire computer system had a slight delay responding to pilot commands and rapid control inputs led to a pilot induced oscillation or pio at landing the vehicle touched down on the main gear then bounced back into the air it touched down again and bounced again more shallowly then touched down again and coasted to a stop needless to say the spectators along the runway including Prince Charles got more than they had expected this pio tendency was soon corrected with a Dryden develop Pio suppression filter that is software changes to the flight control computer here the f8 digital fly-by-wire vehicle proved to be invaluable testing various solutions until the best one was determined three and one-half years later in April of 1981 the excitement at Dryden was at a fever pitch again with tens of thousands of spectators lining the east shore of Rogers dry lake and a thousand or more News personnel scattered around a loud double sonic boom signaled the return of the space shuttle Columbia back from a two-day mission to space Edwards Air Force Base was and continued to be the primary landing site for the Space Shuttle until 1984 since then Edwards is considered the primary backup landing site for the shuttle between 1979 and 1982 Dryden successfully demonstrated a very unique aircraft called the ad one the ad one featured a wing that could be pivoted obliquely from 0 to 60 degrees during flight rather than sweeping both wings back to fly more efficiently at supersonic speeds the whole wing of the ad 1 rotated which greatly simplified the mechanical design while the ad 1 was not specifically designed for high speeds it demonstrated the concept for a possible future high-speed design during this decade aircraft efficiency became more important with the increasing cost of fuel projects like the kc-135 winglets an active and passive laminar flow control projects on the Jetstar the f-111 and F 14 aircraft were explored while laminar flow control concepts have not been used yet on commercial transports winglets have had wide use on many Boeing and Airbus airplanes new technologies for fighter aircraft were also being tested in this decade using two small remotely piloted aircraft called high mat highly maneuverable aircraft technology vehicles only 23.5 feet long it featured a close coupled canard and a narrow elastic tailored composite wing technologies use later in this decade on the x-29 the digital fly-by-wire control system used an auto pilot to fly precise maneuvers to gather large quantities of quality data in a short time hi Matt research brought about far-reaching advances in digital flight control systems which can monitor and automatically correct potential flight hazards the hi map successfully achieved its goals of a 100% increase in aerodynamic efficiency over 1973 technology and maneuverability that would allow a sustained 8g turn at point nine Mach and an altitude of 25 thousand feet by comparison at the same altitude and speed and f-16s maximum sustained turning capability is about 4.5 G's as a tribute to the hi Matt contributions one vehicle now hangs in the Smithsonian Institution's National Air and Space Museum in 1984 NASA and the Federal Aviation Administration FAA teamed up for a flight experiment called the controlled impact demonstration or CID the project's goal was to crash a Boeing 720 airliner to test a fuel additive designed to suppress post-impact fire the additive called anti misting kerosene or a MK demonstrated the ability to inhibit ignition and flame propagation of fuel in simulated crash tests but researchers knew an actual crash would provide more realistic conditions a special site was constructed on Rogers dry lake and cameras were set up to document the tests from every angle including inside the passenger cabin for even more crash data on December 1 1984 with only test dummies extensive instrumentation and 76 thousand pounds of amk on board the old Boeing jet flown remotely by a Dryden pilot Fitz Fulton was crashed onto the specially prepared area of the lake bed with the aircraft touchdown iron posts embedded in the lake bed tore open the fuel tanks the results were surprising the CID impact ended with a spectacular fireball enveloping and destroying the aircraft and everything in it with the FAA on the verge of requiring all US commercial airlines to use a Mk the NASA test discovered that the additive didn't work once again the benefit of flight tests was realized the x-29 a forward swept wing program marked the return of the explains to Dryden after a nine-year absence the two-phase program ran from 1984 to 1992 the first phase concentrated on the proof of concept at low angles of attack and high speeds the second phase of the x29 a program the high angle of attack tests is covered in the fifth decade to x29 a aircraft were built as technical demonstrators to test a forward swept wing with advanced composites variable camber and a thin supercritical airfoil also tested was highly unstable and highly augmented multi-surface controls that required an extremely high gain triple redundant digital control computer with analog backup the fiber strands of the composite aeroelastic tailored wing on the x 29a were specifically aligned to allow it to twist under load the twisting relieve the loads at the tip preventing structural divergence or breakage at high speeds the digital flight control computer system provided sufficient artificial stability and predictable handling qualities in a very unstable aircraft moreover its supercritical wing contributed to good manoeuvring and cruise characteristics in the transonic range despite these accomplishments the predicted higher lift-to-drag ratio did not materialize being about equal to or slightly less than the then-current fighter aircraft the fourth decade brought much publicity to Dryden with the space shuttle flights controlled impact demonstration and the revolutionary x-29 a each of these projects came to Dryden from outside agencies for the world-class expertise and facilities all were successful though not always in the way expected in the words of Hugh L Drive flight research separated the real from the imagined problems and made known the overlooked and the unexpected during the fifth decade at the NASA Dryden Flight Research Center the f-18 high angle of attack vehicle or Harv x-29 a and X 31 explored the region of high angle of attack extensively historically most combat aircraft easily lost control in this flight regime and frequently entered an undesirable spin angle of attack limiters were often implemented to prevent flight in potential spin regimes the f-18 Harve was the number six pre-production f-18 aircraft and had been used previously by the Navy for spin testing it was brought to Dryden in pieces on a flatbed trailer it had been cannibalized and was missing over 400 parts Dryden mechanics and technicians restored the f-18 and named it silk first to indicate its transformation from a sow's ear carcass of missing parts the f-18 Harv was flown in three configurations the standard f-18 with thrust vectoring and with thrust vectoring and actuated for body strikes data was gathered on aerodynamics controls and propulsion the Harv project produced some of Dryden's best surface and smoke flow visualization coming-out flow the flow visualization and surface pressure data was used to improve and validate computational fluid dynamics CFD and Windtunnel research the thrust vectoring greatly improved the handling qualities at high angles of attack and the Harv easily achieved its design point of 70 degree angle of attack in stabilize flight prospect ring also greatly enhanced the mu of the harv in mock aerial combat the actuated nose straight concept proved to be a powerful and precise yaw control device at high angles of attack the Harv program successfully developed new control design and handling qualities criteria for high angle of attack flight the x31 was the first international x-series aircraft with an international test team consisting of DARPA the US Navy the German Ministry of Defence Rockwell International and Deutsche aerospace as the complexities of the program increased Dryden and the Air Force joined the team and the personnel and aircraft were moved to Dryden the x31 was designed for super maneuverability and used lightweight graphite epoxy thrust vectoring veins instead of the heavy inconel metal veins of the heart the aircraft could perform controlled roles at 70 degrees angle of attack and post all 180 degree turns at minimum radius a maneuver known as the herps maneuver or j-turn it performed many mock aerial battles with Dryden f-18s and Nellis f-15s and f-16s as a final show of its capability the x31 demonstrated it's exhilarating post-stall maneuvering at the paris air show in 1996 creating quite a stir in contrast to the f18 Harv and x31 the x-29 a vehicle exhibited good high angle of attack characteristics without the need for thrust vectoring at 45 degrees angle of attack the vehicle demonstrated much better than predicted control and maneuverability at high angle of attack the flow on the wingtips of a forward swept wing remains attached and the ailerons remain effective conversely for a conventional swept back wing the wingtip flow becomes separated before the rest of the wing and the ailerons quickly lose effectiveness even at 67 degrees the maximum angle of attack achieved the x-29 a displayed limited the flight research into laminar flow control at Dryden culminated an experiment on the f-16xl number two active and passive laminar flow experiments had been tested previously on the f-104 f-111 f-14 f-18 flight test fixture Jetstar and the f16 excel number one for the proposed high-speed civil transport laminar flow control offered the single most significant potential improvement in lift over drag ratio of all the aerodynamics technologies considered a successful application could result in significant benefits in reduced takeoff gross weight fuel burn cruise drag engine size emissions and sonic boom on the f-16xl number two a titanium glove perforated with millions of microscopic laser drilled holes was attached to the left wing air was drawn through the tiny hose to ducting to a suction pump in the fuselage this process results in a smooth laminar boundary layer on the surface and results in much lower friction drag than the normal turbulent boundary layer flight test results showed that laminar flow was successfully achieved to nearly the goal of 50% cord in the support of the space shuttle program a convair CV 990 aircraft was modified to test space shuttle tires at various loads sideslip angles and landing speeds these tests were performed to expand the landing envelope of the shuttle a specially designed landing gear was manufactured and installed between the main gear of the CV 990 and could simulate vertical loads of up to 150,000 pounds sideslip up to 15 degrees and landing speeds up to 240 knots a series of tests with the CV 990 were conducted at Edwards and at the Kennedy Space Center Florida in 1993 and 1994 the tests demonstrated that the crosswind limits on the orbiters could be safely increased from 15 to 20 knots expanding the orbiters landing options the Dryden tests also resulted in changes to the runway surface roughness at the Kennedy Space Center during the mid to late 80s and early 90s a series of integrated flight propulsion control research experiments were performed on a NASA f-15 the standard analog control augmentation system CAS was replaced with a digital electronic flight control system but not replacing the standard mechanical flight control system the engines were also specially equipped with digital electronic engine controls projects like the highly integrated digital electronic control project and performance seeking controls project demonstrated significant improvements in thrust range and engine life could be achieved by integration of digital flight engine and Inlet control systems the f-15 also successfully tested a self-repairing flight control system where our control system failure could be detected isolated and the control system reconfigured to obtain satisfactory aircraft performance this particular technology holds significant promise for survivability in a hostile environment in july 1989 a mcdonnell douglas dc-10 airliner lost all means of conventional control when its tail-mounted engine exploded at 37,000 feet severing the aircraft's hydraulic lines the crew learned in real-time how to control the aircraft by varying the thrust on the two remaining wing-mounted engines with emergency equipment waiting the crew attempted to land at the Sioux City Iowa Airport although the flight ended in a fiery crash nearly two-thirds of the passengers survived due largely to the crews heroic efforts the accident inspired a Dryden engineer Bill Berchem to initiate a new project dubbed propulsion controlled aircraft see a bertram and vision software that integrated engine thrust with the digital flight computer to control the aircraft during flight tests engine thrust was commanded by the pc a software to respond to the pilots control inputs which he made using small thumb wheels on the mode control panel in april 1993 nasa pilot Gordon Fullerton successfully landed an f15 using only the engines with the PCA system following that success in August 1995 the program reached its zenith this time Fullerton demonstrated the PCA system in a series of successful landings using only engine power for control on a McDonnell Douglas md-11 airliner while much of Dryden's research during this decade focused on high angle of attack programs significant advancements were made on space shuttle tires and on the benefits of integrating digital flight and engine control systems the sixth decade brought a new focus to Dryden in addition to atmospheric flight research a series of space related projects and unpiloted vehicle concepts were initiated the Ames dc-8 and ER two airborne science aircraft were also transferred to Dryden in 1997 beginning a new era of earth science research f-18 active aeroelastic wing or AAW program investigated the benefits of aerodynamically twisting flexible wings to improve roll maneuverability of high-performance aircraft at transonic and supersonic speeds like this wing warping concept is similar to the technique the Wright brothers used on their early fliers the f-18s wings were modified to increase their flexibility by replacing the wing covers with thinner ones leading edge flap actuators were added to the wing to operate the outboard segment separately from the inboard segments to accommodate these changes the flight control computer software was modified conventional use of control surfaces at high speeds can result in unfavourable wing twisting and reduced control from a phenomena called aileron reversal AAW use the outboard leading-edge flaps and existing ailerons to impart the aerodynamic force necessary to provide the desired roll force AAW control technology can substantially increase control power and reduce aerodynamic drag and aircraft structural weight in future aircraft a derivation of the self-repairing flight control system program a decade earlier the intelligent flight control system or ifcs flown on a highly modified f-15 incorporates the earlier program self learning concepts into flight control software using a neural network it is capable of manipulating far more control surfaces at a faster rate than the first generation self repairing flight control system but ifcs technology is capable of more than simply making a damaged aircraft flying ball for example intelligent flight controls could lead to rapid prototyping of aircraft control laws the autonomous formation flight or AFF program extended the symbiotic relationship of migrating birds by exploiting the performance benefits of aircraft formations the traditional V formation allows all birds but the lead to reduce drag and conserve energy using differential GPS to guide AFF pilots into position a NASA f-18 flew in the wing upwash generated by a lead f-18 and demonstrated a 14% fuel savings at cruise altitude better than the project goal of 10% the automated aerial refueling project aar an outgrowth of the autonomous formation flight program evaluated the capability of an f-18 a aircraft as an in-flight refueling tanker for unmanned air vehicles the project focused on developing accurate analytical models derived from actual flight test data to aid in development of an autonomous aerial refueling system at all the positive closure a little low coming up coming up got it she got it the first ever autonomous probe-and-drogue airborne refueling operation was successfully performed on August 30th 2006 by the autonomous airborne refueling demonstration or Aard project okay we're in pilots were onboard the receiver fa-18 for safety purposes and to fly the aircraft to initial test conditions now you need to give it another 10 feet a global positioning satellite based relative navigation coupled with an optical tracker provided the precise positioning required to put a refueling probe into the center of a 32 inch basket dangling in the air stream behind an airborne tanker as a testament to the autonomous system Dryden pilot dick Ewers and flight test engineer Marty trout assumed a look ma no hands position on the final refuelling demonstration as important as the successful engagements the system also identified and safely recovered from each mr. Tait detected amazement came back on at all I did not do anything projects like the AFF and Aard have helped to establish Dryden's leadership in autonomous aircraft development and flight research I've got it he's got it and we have five four three two one launch launch launch required the x-38 prototypes mark the return of lifting bodies to the Dryden Flight Research Center 10,000 feet like the x-15 and previous lifting bodies the prototypes were dropped from the center's venerable b-52 B bomber the x-38 crew returned vehicle or CRV was conceived as a lifeboat for the International Space Station the x-38 was largely based on the x24 a although it's landing profile would differ significantly once the x-38 CRV had entered the atmosphere and slowed to subsonic speeds it would deploy a large parafoil for landing during flight tests guided by a GPS autopilot the x-38 prototypes demonstrated precise touchdowns on the dry lake bed at Edwards Air Force Base research flights of the prototypes were conducted from 1998 to 2002 when the program was cancelled due to changes in space policy other next generation space vehicle demonstrators met a similar fate the Lockheed Martin x-33 venture star was designed to research the flight characteristics of a full-scale reusable launch vehicle the x-33 was a fully reusable single-stage-to-orbit vehicle that was to operate much like an airliner the orbital sciences x34 technology testbed vehicle was developed to demonstrate key technologies that could be integrated into the reusable launch vehicle program both programs were cancelled in 2001 before either had a chance to fly research platforms of the early 1990s did not satisfy many of NASA's altitude and endurance requirements for earth science missions NASA created a program to mature the technologies necessary to seed the uninhabited air vehicle UAV industry and use this new generation of aircraft for high risk experiments that were previously not feasible for manned missions the program was called the environmental research aircraft and sensor technology arrest two such aircraft were the turboprop-powered General Atomics Aeronautical Systems Inc Altair predator B and the piston engine powered Aurora flight sciences Corp Perseus B both of these ear a stair craft were remotely piloted and designed to fly as high as sixty thousand feet and on missions lasting up to 24 hours or more less conventional ear assed UAVs included the many solar powered flying wings built by Aero vironment Inc Pathfinder plus and Helios prototypes were just two of these aircraft and were used for such missions as observing crops monitoring shoreline testing communications and providing new C detect and avoidance technologies which allows UAVs to steer clear of other aircraft go ahead nasa - we've been watching you bounce around 96 and a half for quite a while now and I think what - probably of all it's uh records flight congratulations I think it's time to room the Helios prototype achieved an ear ass goal by reaching an altitude of ninety six thousand eight hundred sixty three feet in August 2001 as part of NASA's airborne science program Dryden used a modified dc-8 aircraft as a flying laboratory to collect data in support of experimental projects serving the worldwide scientific community originally based at the NASA Ames Research Center the airborne science aircraft were moved to Dryden in 1997 Carol Ella two-five-zero still undone orcas your honor actually we want to hold this altitude the dc-8 flies three primary types of missions sensor development satellite sensor verification and basic research studies of the Earth's surface and atmosphere the dc-8 has flown all over the world allowing scientists to successfully address today's planetary issues including global warming and deforestation in 2006 the university of north dakota began operating the dc-8 under contract and nasa dryden flies to lockheed ER to earth resources research aircraft as high-altitude flying laboratories in the sub orbital science program under the agency's science mission directorate like the dc-8 the er-2 s were moved to Dryden from Ames in 1997 the aircraft collect information about our surroundings including earth resources celestial observations atmospheric chemistry and dynamics and oceanic processes the aircraft also use electronic sensors for research and development satellite calibration and satellite data validation since the airborne science programs inaugural flight on August 31 1971 NASA u2's and er 2s have flown more than 4,500 data missions and test flights to support the scientific research endeavors of NASA other federal agencies states universities and the private sector since the late 1950s the supersonic combustion ramjet has been seen as the means to achieve low-cost access to space and high-speed transportation the scramjet can operate between Mach 5 and near orbital speeds it is far more efficient than a rocket as it burns oxygen from the atmosphere rather than having to carry its own supply but while the potential of a scramjet is great so are the engineering difficulties after some four decades of study and ground research the technology was ready for an actual flight of a scramjet powered aircraft three two one launch launch launch sequencer Rosetta the X 43 made aviation history in March of 2004 with the first successful flight of a supersonic combustion ramjet or scramjet powered airplane at hypersonic speeds speeds greater than Mach 5 or 5 times the speed of sound after being dropped at 40,000 feet from the b-52 the x-43 was accelerated up to near Mach 7 and 94 thousand feet by a pegasus booster ready SEP ready to SEP Tapp separation the x-43 then separated and operated its scramjet for approximately 11 seconds during this time the x-43 accelerated and achieved performance very close to the pre-flight prediction the next and final flight of the x-43a introduce greater unknowns unlike the previous flight the scramjet engine could not be ground tested at Mach 10 for the complete burn because wind tunnels could only simulate those conditions for a thousandth of a second at a time computer analysis predicted that the aerodynamic heating at Mach 10 was twice that at Mach 7 for this flight additional thermal protection in the form of reinforced carbon-carbon composite material had to be added to the leading edges of the x-43 vertical fins launch on my mark in November 2004 the x-43a and Pegasus were dropped from the b-52 after being accelerated to Mach nine point six and one hundred nine thousand feet altitude the vehicle separated and the x-43a successfully sustained the desired cruise speed again the flight data correlated well with pre-flight predictions ERV is stable at this time nasa dryden remains the premier aeronautical flight research center of the nation and not simply because of its location and accomplishments over the decades with a can-do attitude it has developed an extraordinarily knowledgeable workforce with diverse specialties from subsonic to hypersonic aerodynamics atmospheric to exo-atmospheric physiology powered and unpowered as well as piloted and unpiloted aircraft in the process Dryden has pioneered a host of new technologies and methodologies related to aeronautics its engineers have been awarded patents and national research awards and it's pilots have been recognized with Collier and Harmon trophies just as important is Dryden's vast experience in developing and executing all manner of flight research programs small and large national and international in-house or through partnerships these are the attributes that continue to make Dryden the place to come for world-class flight research you

Channel: AIRBOYD

Views: 62,836

Rating: 4.8532109 out of 5

Keywords: boeing, #avgeek, luftfahrt, airport, The, Body, #AVGEEK, EM-0093-01, airbus, aviation, X-Plane, Early, Space, airplane, FAA, history, aeroplane, Technology, plane, Era, cockpit, airline, takeoff, flying, Lifting, Shuttle, airboyd, NTSB, Demonstration, chemtrails, Vectoring, Boeing, planes, Thrust, prop, AOPA, X-15, Alpha, pilot, #airboyd, jet, yt:quality=high, Airbus, landing, High

Id: NIrt0L8O4cM

Length: 72min 23sec (4343 seconds)

Published: Mon Jan 18 2010