Sixty-years ago this week, the USAF/Boeing YB-52 Stratofortress (S/N 49-231) all-jet strategic bomber took to the air on its maiden flight. The crew for this historic event consisted of Boeing’s Alvin M. “Tex” Johnston (command pilot) and USAF Lt Col Guy M. Townsend (co-pilot). The B-52 was designed by the Boeing Company for the United States Air Force in the 1940’s. Its mission was to provide the Strategic Air Command (SAC) with a global nuclear strike capability. As originally designed, the B-52 featured a top speed of 513 mph at 35,000 feet and a range of 6,005 nm for a gross take-off weight of 280,000 lbs. Power was provided by an octet of Pratt and Whitney J-57 turbojets; each of which generated a maximum sea level thrust of about 10,000 lbs. With a fuselage length of 160 feet, the B-52 was configured with a huge wing having a span of 185 feet and a leading edge sweep of 35 degrees. The initial pair of prototype B-52 aircraft (S/N 49-230 and S/N 49-231)received the designation of XB-52. However, the second XB-52 (S/N 49-231) was subsequently designated as the YB-52 and was the first B-52 airframe to fly. It did so on Tuesday, 15 April 1952. This 2.35-hour maiden flight originated from Boeing Field near Seattle, Washington and recovered at Larson AFB, Washington. The big airplane performed well on its initial foray into the wild blue yonder and it was clear from the start that USAF and Boeing had a winner. Indeed, the Stratofortress would go on to a storied career whose length and breadth could not have been foreseen by its creators. The type’s speed, range and gross weight would increase over the years. New and more powerful engines would provide the improved performance. A total of 744 copies of the B-52 were built in eight (8) different production versions (B-52A through B-52H); roughly 90 of which are still flying. Amazingly, three (3) generations of Air Force pilots have flown the aircraft. With a service period that began in the Cold War and extends into the present, the B-52 Stratofortress holds the distinction of being the longest serving bomber aircraft in the history of military aviation.
Forty-seven years ago this week, the first International Telecommunications Satellite (Intelsat I) was launched into a geosynchronous orbit by a Thrust-Augmented Delta (TAD) launch vehicle. Popularly known as Early Bird, the satellite holds the distinction of being history’s first commercial communications orbital platform. It was also the first satellite to provide direct and quasi-instantaneous communication between the North American and European continents including transmission of television, telephone, and telefax signals. Fired into orbit from LC-17A at Cape Canaveral, Florida on Tuesday, 06 April 1965, Early Bird consisted of a 28-inch diameter cylinder measuring 23-inches in height. Spin-stabilized about its longitudinal axis, the satellite weighed just 85 lbs. Power was provided by an array of 6,000 solar cells covering its external surface. Early Bird was capable of handling 240 two-way telephone circuits or a single TV channel via a pair of 6-watt transmitters. Though primitive by today’s standards, Early Bird functioned well its role as a communications satellite. Among its many accomplishments, the satellite helped make possible the first live television broadcast of the splashdown of a manned spacecraft when Gemini 6 returned to earth in December of 1965. Early Bird was deactivated in January of 1969 following a 48-month service period that began on Monday, 28 June 1965. This service duration was well beyond the type’s original design life of 18 months. When the Atlantic Intelsat satellite failed at a most inopportune moment, Early Bird was returned to operational status on Sunday, 29 June 1969 to support the Apollo 11 mission. This reactivation period was brief and ended on Wednesday, 13 August 1969. With the exception of a short period of reactivation in 1990 to honor its 25th launch anniversary, Early Bird has silently orbited the Earth ever since. The Intelsat Program grew remarkably following the fledging flight of Early Bird so long ago. Indeed, more than 120 Intelsat and Intelsat-derivative satellites have been orbited by a variety of American, Russian, French and Chinese launch vehicles since 1965.
Forty-nine years ago this week, the United States successfully conducted the fourth Saturn I test flight designated as Saturn-Apollo No. 4 (SA-4). Launched from LC-34 at Cape Canaveral, Florida on Thursday, 28 March 1963, SA-4 reached an apogee of 70 nm, attained a maximum speed of 3,670 mph and flew 216 nm downrange during the brief 15 minute suborbital mission. The Saturn I measured 180 feet in length, featured a maximum diameter of 21.4 feet and weighed 1,123,600 l bs at lift-off. The first stage propulsion system consisted of an octet of H-1 engines generating a total sea level thrust of 1,600,000 lbs. Nominal burn time was 150 seconds. Part of the early Apollo Program, SA-4 was the last flight to fire just the first stage rocket engines. As with the previous three launches, the primary goal of SA-4 was to validate the structural integrity of the Saturn I vehicle. However, a significant additional objective of SA-4 was to verify the GNC system’s ability to properly handle an engine-out anomaly during first stage operation. As such, one of the H-1 engines was programmed to intentionally shutdown at approximately T+100 seconds. The GNC system did indeed respond properly to this anomaly by rerouting propellants to the remaining seven (7) engines which burned longer to compensate for the loss of thrust. SA-4 also employed a nonfunctional second stage which incorporated the external shape of the ultimate second stage design. This included the presence of vent ducts, fairings, simulated camera pods and various externally-mounted antennae. SA-4 also fired a retrorocket system that would be employed to aid separation of various rocket stages on later flights. Despite dire warnings in some quarters, the shutdown H-1 engine remained intact despite the build-up of heat caused by the lack of cooling propellant flowing around the nozzle. This survivability feature underscored the robustness of the clustered engine concept employed in the Saturn series of space boosters. Interestingly, the engine-out compensation capability demonstrated on SA-4 was in fact successfully employed during a pair of later Apollo missions; Apollo 6 and Apollo 13.
Fifty-years ago this week, a supersonic flight test of the B-58A Hustler’s crew escape system was successfully conducted with a black bear named Yogi as the test subject. Ejection took place with the test aircraft maintaining a speed of 850 mph at 35,000 feet. The USAF/Convair B-58A Hustler was the world’s first operational supersonic strategic bomber. With a GTOW of 176,000 lbs and powered by a quartet of General Electric J79-GE-5A turbojets, the aircraft featured a maximum speed of Mach 2 at 40,000 feet. The Hustler air crew consisted of a pilot, bombardier/navigator and defensive systems officer seated in separate, tandem flight stations. When the Hustler entered the operational inventory in 1960, standard ejection seats were used for air crew emergency egress. However, the chances of surviving a supersonic ejection in the B-58A or any other aircraft were quite low due to severe wind blast and exposure effects. The resolution of this issue came in the form of an encapsulation system that protected the crew member during ejection, deceleration, parachute deployment and landing. Upon activation, clamshell doors would close and seal the crew member in the escape capsule. The entire assembly was then fired out the top of the aircraft and into the air stream. Flight testing of this system was initially performed using bears due to the similarity of their internal organ arrangement with that of a man’s. On Wednesday, 21 March 1962, a 2-year old female black bear named Yogi served as the first live test subject. The tranquilized bear survived the ride upstairs, the ejection event, 7.5 minute parachute descent and landing with no apparent ill effect. Subsequent testing with other bears helped prove the escape system’s airworthiness. Although many sources claim that this was the first supersonic ejection of a live creature, such is not the case. That particular distinction (if it can be called that) goes to North American Aviation pilot George F. Smith who bailed out of his stricken F-100 Super Sabre at 777 mph on Sunday, 26 February 1955. Although battered and terribly injured in the process, Smith survived and lived to fly another day.
Forty-one years ago this month, the first long-tank thrust-augmented Delta rocket with six Castor-2 strap-on boosters was launched from LC-17A at Cape Canaveral, Florida. Known as Delta M-6, the thrust-augmented launch vehicle was capable of placing 1,000 lbs in geosynchronous transfer orbit (GTO) or about 2,850 lbs in low earth orbit (LEO). Three of the solid strap-on boosters were ignited on the pad along with the MB-3-3 first stage liquid rocket motor which generated 195,000 lbs of vacuum thrust. Each solid rocket strap-on produced 58,000 lbs of vacuum thrust and burned for 37 seconds. At T+38 seconds, the remaining three strap-ons were air-ignited just as the ground-ignited motors were burning out. All of the Castor-2 solid rockets separated from the launch vehicle shortly after burnout of the trio of air-ignited motors. The ground-ignited boosters went first, followed 5 seconds later by the air-ignited set. The primary payload for the Delta M-6 mission was the Explorer 43 satellite which was inserted into a highly-elliptical orbit on Saturday, 13 March 1971. Orbital parameters included an apogee of 122,146 statute miles a perigee of 146 statute miles and an orbit inclination of 28.75 degees. Outfitted with a dozen specialized instruments, Explorer 43 obtained detailed scientific measurements of solar ray, cosmic ray, electrical field and energetic particle activity in space. These data allowed scientists to study the cislunar environmnt during a period of decreasing solar flare activity. Explorer 43 performed well right up to the day it reentered the Earth’s atmosphere on Thursday, 02 October 1974.
Forty-three years ago this month, the Apollo Lunar Module (LM) flew in space for the first time during the Apollo 9 earth-orbital mission. This technological achievement was critical to the success of the first lunar landing mission which occurred a little over 4 months later. The Apollo Lunar Module (LM) was the world’s first true spacecraft in that it was designed to operate in vacuum conditions only. It was the third and final element of the Apollo spacecraft; the first two elements being the Command Module (CM) and the Service Module (LM). The LM had its own propulsion, life-support and GNC systems. The vehicle weighed about 32,000 lbs on Earth and was used to transport a pair of astronauts from lunar orbit to the lunar surface and back into lunar orbit. The spacecraft was really a two-stage vehicle; a descent stage and an ascent stage weighing 22,000 lbs and 10,000 lbs on Earth, respectively. The descent stage rocket motor was throttable and produced a maximum thrust of 10,000 lbs while the ascent stage rocket motor was rated at 3,500 lbs of thrust. On Monday, 03 March 1969, Apollo 9 was rocketed into earth-orbit by the mighty Saturn V launch vehicle. The primary purpose of this mission was to put the first LM through its paces preparatory to the first lunar landing attempt. During the 10-day mission, the crew of Commander James A. McDivitt, CM Pilot David R. Scott and LM Pilot Russell L. “Rusty” Schweickart fully verified all moon landing-specific operational aspects (short of an actual landing) of the LM. Key activities included multiple-firings of both rocket motors and several rendezvous and docking exercises in which the LM flew as far as 113 miles from the CM/SM pair. By the time the crew splashed-down in the Atlantic Ocean on Thursday, 13 March 1969, America had a new operational spacecraft and a fighting chance to land men on the moon and safely return them to Earth by the end of the decade.
Fifty-two years ago this week, the Strategic Air Command (SAC) fired its first USAF/North American AGM-28 Hound Dog cruise missile. A USAF/Boeing B-52G Stratofortress from the 4135th Strategic Wing at Eglin AFB, Florida served as the air-launch platform. The AGM-28 Hound Dog was a turbojet-powered cruise missile designed to penetate enemy air space and deliver a 1 megaton-yield thermonuclear warhead. The vehicle measured 42.5 feet in length, 2.33 feet in diameter and had a wing span of 12 feet. Launch weight was 10,140 lbs. The type’s non-afterburning Pratt and Whitney J52-6 turbojet was rated at 7,500 lbs of sea level thrust and could propel it to a maximum speed of about 1,430 mph (Mach 2.1). Interestingly, the AGM-28’s turbojets were run at full power, making the B-52 carrier bomber a 10 engine aircraft. Following take-off, the Hound Dog’s engines were shutdown and its fuel tanks topped-off. The Hound Dog’s flight envelope was such that it could cruise anywhere between tree-top level and 55,000 feet. Two vehicles were externally-carried by the B-52 launch aircraft; one each from the right and left wing pylon stations. Maximum post-launch flyout range was about 617 nm. North American Aviation began development of the missile in 1957 and the first powered flight occurred in April of 1959. A series of flight tests ensued that proved the missile’s various systems including radar, guidance, navigation and control. These developmental activities culminated with the first SAC shot on Monday, 29 February 1960 and establishment of an Initial Operating Capability (IOC) shortly thereafter. A total of 772 Hound Dog airframes were built and served in the SAC inventory through 1976. The Hound Dog served well as a deterent to nuclear confrontation between the United States and the Soviet Union; no Hound Dog was ever fired in anger.
Forty-seven years ago today, NASA’s Ranger 8 spacecraft successfully completed a mission to obtain high-resolution photographs of the lunar surface. The flight was the penultimate mission in the Ranger Program, the goal of which was to help scientists better understand the topography of potential Apollo lunar landing sites. Ranger 8’s mission began with launch from LC-12 at Cape Canaveral, Florida on Wednesday, 17 February 1965. The Atlas-Agena B launch vehicle placed Ranger 8 along a direct hyperbolic trajectory that would allow the spacecraft to intercept the Moon nearly 65 hours later. The mission aim point was situated in the Mare Tranquilitatis region of the lunar surface. All of the action would take place in the final 23 minutes of flight as a complement of six (6) vidicon cameras snapped photos all the way to impact. A pair of the cameras featured a full scan capability; one wide-angle, one narrow-angle. The remaining four (4) cameras were partial scan systems; two wide-angle, two narrow-angle. Ranger 8 arrived at the Moon on Saturday, 20 February 1965. The first of 7,137 high-resolution photos was taken at an altitude of 1,388 nm above the lunar surface. The last photo, featuring a resolution of about 5 feet, was imaged when the Ranger 8 spacecraft was only 525 feet above the surface; a mere 0.09 seconds before a 6,000-mph impact with the Moon. Impact occurred only 10 nm from the mission aim point. This was exceptional accuracy considering the trip from Earth was over 205,000 nm. While Ranger 8’s mission was brief and its end violent, the photographic bounty transmitted back to Earth helped make possible America’s first manned lunar landing on Sunday, 20 July 1969. The landing site? None other than Mare Tranquilitatis.
Fifty-three years ago this week, the U.S. Navy’s first production Martin P6M-2 SeaMaster flyingboat took-off from Chesapeake Bay on its maiden flight. Martin chief test pilot George A. Rodney was at the controls of the 4-man, swept-wing naval bomber as it took to the skies on Tuesday, 17 February 1959. Featuring a fuselage length of 134 feet, wingspan of 102 feet, and a wing leading edge sweep of 40 degrees, the P6M-2 had a GTOW of about 175,000 lbs. Armament included an ordnance load of 30,000 lbs and twin 20 mm, tail-mounted cannon. Power was provided by a quartet of Pratt and Whitney J75-P-2 turbojets; each delivering a maximum sea level thrust of 17,500 lbs. The SeaMaster’s demonstrated top speed at sea level was in excess of Mach 0.90. This on-the-deck performance is comparable to that of the USAF/Rockwell B-1B Lancer and USAF/Northrup B-2 Spirit and exceeds that of the USAF/Boeing B-52 Stratofortress. P6M pilots reported that the aircraft handled well below 5,000 feet when flying at Mach numbers between 0.95 and 0.99. While designed for low altitude bombing and mine-laying, the aircraft was flown as high as 52,000 feet. As a result, the Navy even considered the SeaMaster as a nuclear weapons platform. Despite the type’s impressive performance and capabilities, the SeaMaster Program was cancelled in August of 1959. Budgetary issues and the emerging Fleet Ballistic Missile System (Polaris-Poseidon-Trident) led to this decision. Loss of the P6M SeaMaster Program was devastating to the Glenn L. Martin Company and resulted in this notable aerospace business never again producing another aircraft.
Fifty-years ago this week, the NASA TIROS IV meteorological satellite was successfully orbited by a United States Air Force Thor-Delta launch vehicle. Launch took place from LC-17A at Cape Canaveral, FL on Thursday, 08 February 1962. The TIROS (Television Infra Red Observation Satellite) Program marked the first use of satellite technology to provide near-continuous photographic coverage of global cloud formations from space. Historically, TIROS photos were instrumental in helping mature the science/art of global weather forecasting. The TIROS IV mission was designed to maintain an operational TIROS in orbit for an extended period and to obtain improved photographic data to be used in weather forecasting during the northern hemisphere hurricane season. The cylindrical spacecraft measured 42 inches in diameter and 19 inches in height. Constructed of aluminum and stainless steel, TIROS IV weighed 285 lbs. A bank of 63 onboard batteries was charged via an array of 9,260 solar cells that covered the vehicle’s external surface. The satellite carried an upgraded lens system to improve the clarity of photos taken by its twin cameras. As a result, TIROS IV photos were the best to date in the TIROS Program. An international facsimile transmission network was also instituted that allowed the US Weather Service to share photos with weather services worldwide. From its nearly circular orbit of 420 nm above the surface of the Earth, TIROS IV snapped over 32,000 photos over the course of its 161-day mission.
