Sixty-one years ago this month, the United States Army’s Bumper-WAC No. 7 two-stage rocket reached a maximum speed of 8,213 ft/sec (Mach 9). This concluding flight of the Bumper Program was flown from the Long-Range Proving Ground (LRPG) in Florida.
The Bumper Program was a United States Army effort to reach flight altitudes and velocities never before achieved by a rocket vehicle. The name “Bumper” was derived from the fact that the lower stage would act to “bump” the upper stage to higher altitude and velocity than it (i.e., the upper stage) was able to achieve on its own.
The Bumper Program, which was actually part of the Army’s Project Hermes, officially began on Friday, 20 June 1947. The project team consisted of the General Electric Company, Douglas Aircraft Company and Cal Tech’s Jet Propulsion Laboratory. A total of eight (8) test flights took place between May 1948 and July 1950.
The Bumper two-stage configuration consisted of a V-2 booster and a WAC Corporal upper stage. The V-2′s had been captured from Germany following World War II while the WAC Corporal was a single stage American sounding rocket. The launch stack measured 62 feet in length and weighed around 28,000 pounds.
Propulsion-wise, the V-2 booster generated 60,000 pounds of thrust with a burn time of 70 seconds. The WAC Corporal rocket motor produced 1,500 pounds of thrust and had a burn time of 47 seconds.
The flight of Bumper-WAC No. 1 occurred on Thursday, 13 May 1948. This was an engineering test flight in which the WAC Corporal achieved a peak altitude of 79 miles. Unfortunately, the next three (3) flights were plagued by development problems of one kind or another and failed to achieve an altitude of even 10 miles.
Bumper-WAC No. 5 was fired from WSPG on Thursday, 24 February 1949. The V-2 burned-out at an altitude of 63 miles and a velocity of 3,850 feet per second. The WAC Corporal accelerated to a maximum velocity of 7,550 feet per second and then coasted to an apogee of 250 miles. With generation of a very thin bow shock layer and high aerodynamic surface heating levels, this flight can be considered as the first time a man-made flight vehicle entered the realm of hypersonic flight.
Three (3) more Bumper-WAC missions would follow Bumper-WAC No.5. While Bumper-WAC No. 6 would fly from WSPG, the final two (2) missions were conducted from an isolated Florida launch site in July of 1950. The hot, bug-infested Floridian launch location, springing-up amongst sand dunes and scrub palmetto, would one day become the seat of American spaceflight. It was known then as the Long-Range Proving Ground (LRPG). Today, we know it as Cape Canaveral.
Bumper-WAC No. 7 was supposed to be the first rocket fired from the LRPG. However, Bumper-WAC No. 8 got that honor when No. 7 experienced a glitch on the pad. No. 8 was fired at 13:29 UTC on Monday, 24 July 1950. The mission failed when the rocket motor of the WAC upper stage did not ignite.
On Saturday, 29 July 1950, Bumper-WAC No. 7 was launched from the LRPG. The resulting flight achieved the highest kinematic performance of the Bumper Program. The WAC upper stage burned-out at 8,213 ft/sec (Mach 9) and flew 150 miles downrange. The maximum velocity within the atmosphere was more than 3,200 mph – a record for the time.
The Bumper Program successfully demonstrated the efficacy of the multi-staging concept. Bumper also provided valuable flight experience in stage separation and high altitude rocket motor ignition systems. In short, Bumper played a vital role in helping America successfully develop its ICBM, satellite and manned spaceflight capabilities.
While its historical significance, and even its existence, has been lost to many here in the 21st Century, the Bumper Program played a major role in our quest for the Moon. As such, it will forever hold a hollowed place in the annals of United States aerospace history.
On 11-15 July 2011, White Eagle Aerospace returned to the National Air & Space Intelligence Center (NASIC) outside of Dayton, OH to hold its Fundamentals of Earth Reentry professional short course. NASIC, headquartered at Wright-Patterson Air Force Base, is the principal provider of foreign aerospace intelligence to the US Department of Defense. This marks the third technical training course held at Wright-Patterson Air Force Base, OH.
Fundamentals of Earth Reentry Short Course
National Air & Space Intelligence Center (NASIC)
Wright-Patterson Air Force Base, OH
11 – 15 July 2011
Fundamentals of Earth Reentry is designed and taught by J.Terry White, company founder and Aerosciences Instructor at White Eagle Aerospace. This intensive training program is designed for the aerospace professional seeking expert instruction in the basic principles, science and technology of entry into the Earth’s atmosphere. The course provides the basic technical knowledge needed to intelligently address the critical aspects of atmospheric entry from suborbital and orbital flight.
White Eagle Aerospace is honored to serve NASIC, the military and civilian personnel of both the United States Air Force and the US Department of Defense. The WEA team wishes to thank each student who attended the Fundamentals of Earth Reentry course and expresses sincere gratitude to Mr. Nathan Setters, Ms. Jennifer Toth and Ms. Aurea Rivera (Technical Director, NASIC Data Analysis Group) for their invaluable assistance in facilitating this course.
Fifty-years ago this week, Mercury Seven Astronaut Vigil I. “Gus” Grissom, Jr. became the second American to go into space. Grissom’s suborbital mission was flown aboard a Mercury space capsule that he named Liberty Bell 7.
The United States first manned space mission was flown on Friday, 05 May 1961. On that day, NASA Astronaut Alan B. Shepard, Jr. flew a 15-minute suborbital mission down the Eastern Test Range in his Freedom 7 Mercury spacecraft. Known as Mercury-Redstone 3, Shepard’s mission was entirely successful and served to ignite the American public’s interest in manned spaceflight.
Shepard was boosted into space via a single stage Redstone rocket. This vehicle was originally designed as an Intermediate-Range ballistic Missile (IRBM) by the United States Army. It was man-rated (that is, made safer and more reliable) by NASA for the Mercury suborbital mission. A descendant of the German V-2 missile, the Redstone produced 78,000 lbs of sea level thrust.
Shepard’s suborbital trajectory resulted in an apogee of 101 nautical miles (nm). With a burnout velocity of 7,541 ft/sec, Freedom 7 splashed-down in the Atlantic Ocean 263 nm downrange of its LC-5 launch site at Cape Canaveral, Florida. Shepard endured a maximum deceleration of 11 g’s during the reentry phase of the flight.
Mercury-Redstone 4 was intended as a second and confirming test of the Mercury spacecraft’s space-worthiness. If successful, this mission would clear the way for pursuit and achievement of the Mercury Program’s true goal which was Earth-orbital flight. All of this rested on the shoulders of Gus Grissom as he prepared to be blasted into space.
Grissom’s Liberty Bell 7 spacecraft was a better ship than Shepard’s steed from several standpoints. Liberty Bell 7 was configured with a large centerline window rather than the two small viewing ports featured on Freedom 7. The vehicle’s manual flight controls included a new rate stabilization system. Grissom’s spacecraft also incorporated a new explosive hatch that made for easier release of this key piece of hardware.
Mercury-Redstone 4 (MR-4) was launched from LC-5 at Cape Canaveral on Friday, 21 July 1961. Lift-off time was 12:20:36 UTC. From a trajectory standpoint, Grissom’s flight was virtually the same as Shepard’s. He found the manual 3-axis flight controls to be rather sluggish. Spacecraft control was much improved when the new rate stabilization system was switched-on. The time for retro-fire came quickly. Grissom invoked the retro-fire sequence and Liberty Bell 7 headed back to Earth.
Liberty Bell 7’s reentry into the Earth’s atmosphere was conducted in a successful manner. The drogue came out at 21,000 feet to stabilize the spacecraft. Main parachute deployed occurred at 12,300 feet. With a touchdown velocity of 28 ft/sec, Grissom’s spacecraft splashed-down in the Atlantic Ocean 15 minutes and 32 seconds after lift-off. America now had both a second spaceman and a second successful space mission under its belt.
Following splashdown, Grissom logged final switch settings in the spacecraft, stowed equipment and prepared for recovery as several Marine helicopters hovered nearby. As he did so, the craft’s new explosive hatch suddenly blew for no apparent reason. Water started to fill the cockpit and the surprised astronaut exited the spacecraft as quickly as possible.
Grissom found himself outside his psacecraft and in the water. He was horrfied to see that Liberty Bell 7 was in imminent peril of sinking. The primary helicopter made a valiant effort to hoist the spacecraft out of the water, but the load was too much for it. Faced with losing his vehicle and crew, the pilot elected to release Liberty Bell 7 and abandon it to a watery grave.
Meanwhile, Grissom struggled just to stay afloat in the churning ocean. The prop blast from the recovery helicopters made the going even tougher. Finally, Grissom was able to retrieve and get himself into a recovery sling provided by one of the helicopters. He was hoisted aboard and subsequently delivered safely to the USS Randolph.
In the aftermath of Mercury-Redstone 4, accusations swirled around Grissom that he had either intentionally or accidently hit the detonation plunger that activated the explosive hatch. Always the experts on everything, especially those things they have little comprehension of, the denizens of the press insinuated that Grissom must have panicked. Grissom steadfastly asserted to the day that he passed from this earthly scene that he did no such thing.
Liberty Bell 7 rested at a depth of 15,000 feet below the surface of the Atlantic Ocean until it was recovered by a private enterprise on Tuesday, 20 July 1999; a day short of the 38th anniversary of Gus Grissom’s MR-4 flight. The beneficiary of a major restoration effort, Liberty Bell 7 is now on display at the Kansas Cosmosphere and Space Center. The spacecraft’s explosive hatch was never found.
As for Gus Grissom, ultimate vindication of his character and competence came in the form of his being named by NASA as Commander for the first flights of Gemini and Apollo. Indeed, Grissom and rookie astronaut John W. Young successfully made the first manned Gemini flight in March of 1965 during Gemini-Titan 3. Later, Grissom, Edward H. White II and Roger B. Chaffee trained as the crew of Apollo 1 which was slated to fly in early 1967. History records that their lives were cut short in the tragic and infamous Apollo 1 Spacecraft Fire of Friday, 27 January 1967.
Fifty-six years ago this month, the USAF/Republic XF-84H experimental turboprop fighter took to the air for the first time. The test hop originated from and recovered at Edwards Air Force Base, California.
The turbojet-powered XF-84H was a variant of Republic Aviation’s F-84 Thunderstreak. An Allison XT40-A-1 turboprop engine, rated at 5,850 hp, served as the power source for this novel aircraft. The XT40 drove a variable-pitch, 3-blade, 12-foot diameter propeller at 3,000 rpm. Thrust level was changed by varying blade pitch.
Owing to its high rotational speed and large diameter, the outer 2 feet of the XF-84H propeller saw supersonic velocities. The shock waves that emanated from the prop produced a deafening wall of sound. The extreme sound level produced intense nausea and raging headaches in ground crewmen. As a result, the XF-84H was dubbed the “Thunderscreech”.
The prop wash from the aircraft’s powerful turboprop necessitated the use of a T-tail to keep the horizontal tail and elevator in clean air flow. The engine’s extreme torque was partially countered by differential deflection on the left and right wing flaps and by placement of the left wing root air intake a foot ahead of the right intake.
A pair of XF-84H prototype aircraft (S/N 51-17059 and S/N 51-17060) was built by Republic Aviation. The first flight of an XF-84H took place on Friday, 22 July 1955 at Edwards Air Force. The flight was made by Republic test pilot Henry G. “Hank” Beaird, Jr. in Ship No. 1 (S/N 51-17059). The flight was cut short by a forced landing.
A total of twelve (12) test flights were made in the two Thunderscreech prototypes; eleven (11) in Ship No. 1 and one (1) in Ship No. 2. Total flight time accumulated by these experimental airframes was 6 hours and 40 minutes. The majority of flights experienced forced landings for one reason or another.
The XF-84H suffered from reduced longitudinal stability and poor handling qualities. The aircraft was also plagued by frequent engine, hydraulic system, nose gear and vibration problems. Faced with the type’s obvious non-viability, USAF opted to cancel the XF-84H Program in September of 1956.
Historical records indicate that the XF-84H reached a top speed of 520 mph during its brief flight test life. This figure was a full 120 mph short of the aircraft’s design speed. Nonetheless, the XF-84H held the speed record for single-engine prop-driven aircraft until Monday, 21 August 1989. On that date, a specially modified Grumman F8F Bearcat established the existing record of 528.33 mph.
Twenty-nine years ago today, the Space Shuttle Columbia landed at Edwards Air Force Base to successfully conclude the fourth orbital mission of the Space Transportation System. Columbia’s return to earth added a special touch to the celebration of America’s 207th birthday.
STS-4 was NASA’s fourth Space Shuttle mission in the first fourteen months of Shuttle orbital flight operations. The two-man crew consisted of Commander Thomas K. Mattingly, Jr. and Pilot Henry W. Hartsfield who were both making their first Shuttle orbital mission. STS-4 marked the last time that a Shuttle would fly with a crew of just two.
STS-4 was launched from Cape Canaveral’s LC-39A on Sunday, 27 June 1982. Lift-off was exactly on-time at 15:00:00 UTC. Interestingly, this would be the only occasion in which a Space Shuttle would launch precisely on-time. The Columbia weighed a hefty 241,664 lbs at launch.
Mattingly and Hartsfield spent a little over seven (7) days orbiting the Earth in Columbia. The orbiter’s cargo consisted of the first Getaway Special payloads and a classified US Air Force payload of two missile launch-detection systems. In addition, a Continuous Flow Electrophoresis System (CFES) and the Mono-Disperse Latex Reactor (MLR) were flown for a second time.
The Columbia crew conducted a lightning survey using manual cameras and several medical experiments. Mattingly and Hartsfield also maneuvered the Induced Environment Contamination Monitor (IECM) using the Orbiter’s Remote Manipulator System (RMS). The IECM was used to obtain information on gases and particles released by Columbia in flight.
On Sunday, 04 July 1982, retro-fire started Columbia on its way back to Earth. Touchdown occurred on Edwards Runway 22 at 16:09:31 UTC. This landing marked the first time that an Orbiter landed on a concrete runway. (All three previous missions had landed on Rogers Dry Lake at Edwards.) Columbia made 112 complete orbits and traveled 2,537,196 nautical miles during STS-4.
The Space Shuttle was declared “operational” with the successful conduct of the first four (4) shuttle missions. President Ronald Reagan and First Lady Nancy Reagan even greeted the returning STS-4 flight crew on the tarmac. However, as history has since taught us, manned spaceflight still comes with a level of risk and danger that exceeds that of military and commercial aircraft operations. It will be some time before a manned space vehicle is declared operational in the desired sense.