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Home For the Fourth

Thirty-six 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 and patriotic touch to the celebration of our nation’s 206th 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. This mission stands as the first occasion in which a Space Shuttle launch would occur precisely on-time. The Columbia orbiter 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 of the Orbital Maneuvering System (OMS) engines 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 optimistically 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 space history has taught us, manned spaceflight still comes with a level of risk and danger that exceeds that of military and commercial aircraft operations. Despite its unparalleled accomplishments and enduring legacy, the Space Shuttle was never operational in the true and desired sense.

Posted in Aerospace, History

Flying by Knight

Sixty-one years ago this week, USAF Major William F. “Pete” Knight made an emergency landing in X-15 No. 1 at Mud Lake, Nevada. Knight somehow managed to save the hypersonic aircraft following a complete loss of electrical power as the vehicle passed through 107,000 feet during the climb.

The famed X-15 Program conducted 199 flights between June 1959 and October 1968. North American Aviation (NAA) built three (3) X-15 aircraft. Twelve (12) men from NAA, USAF and NASA flew the X-15. Eight (8) pilots received astronaut wings for flying the X-15 beyond 250,000 feet. One (1) aircraft and one (1) pilot were lost during flight test.

The X-15 flew as fast as 4,520 mph (Mach 6.7) and as high as 354,200 feet. The basic airframe measured 50 feet in length, featured a wing span of 22 feet and had a gross weight of 33,000 pounds. The type’s Reaction Motors XLR-99 rocket engine burned anhydrous ammonia and liquid oxygen to produce a sea level thrust of 57,000 pounds. The X-15 used both 3-axis aerodynamic and ballistic flight controls.

An X-15 mission was fast-paced. Flight time from B-52 drop to unpowered landing was typically 10 to 12 minutes in duration. The pilot wore a full pressure suit and experienced 6 to 7 G’s during pull-out from max altitude. There really was no such thing as a routine X-15 mission. However, all X-15 missions had one factor in common; high danger.

On Thursday, 29 June 1967, X-15 No. 1 (S/N 56-6670) made its 73rd and the X-15 Program’s 184th free flight. Launch took place at 1828 UTC as the NASA B-52B launch aircraft (S/N 52-0008) flew at Mach 0.82 and 40,000 feet near Smith Ranch, Nevada. Knight, making his 10th X-15 flight, quickly ignited the XLR-99 and started the climb upstairs.

The X-15 was performing well and Knight was enjoying the flight until 67.6 seconds into a planned 87 second XLR-99 burn. That’s when the engine suddenly quit. A couple of heartbeats later, the Stability Augmentation System (SAS) failed, the Auxiliary Power Units (APU’s) ceased operating, the X-15’s generators stopped functioning and the cockpit lights went out. This was the total hit; a complete power failure.

Pete Knight was now just along for the ride. No thrust to power the aircraft. No electrical power to run onboard systems. No hydraulics to move flight controls. Even the reaction controls appeared inoperative. The X-15 continued upward, but it wallowed aimlessly in the low dynamic pressure of high altitude flight. At this point, Knight considered taking his chances and punching-out.

The X-15 went over the top at 173,000 feet. On the way downhill, Knight was able to get some electrical power from the emergency battery. This meant that he now had some hydraulic power and could utilize the X-15’s flight control surfaces. Knight next tried to fire-up the APU’s. The right APU would not respond. The left APU fired, but the its generator would not engage.

As the X-15 descended and the dynamic pressure built-up, Knight was able to maneuver his stricken X-15. He headed for Mud Lake in a sustained 6-G turn. As he leveled off at 45,000 feet, Knight instinctively knew he could now make the east shore of the Nevada dry lake. But it was tough work to fly the X-15. Knight ended-up using both hands to fly the airplane; one hand on the side stick and one hand on the center stick.

While Knight was trying to get his airplane down on the ground in one piece, only he and his Maker knew his whereabouts. The X-15 flight test team certainly didn’t, since Knight’s radio, telemetry and radar transponder were now inop. Further, the X-15 was not being skinned tracked at the time of the electrical anomaly. Just before he touched-down at Mud Lake, Knight’s X-15 was spotted by NASA’s Bill Dana who was flying a F-104N chase aircraft.

Pete Knight made a good landing at Mud Lake. The X-15 slid to a stop. After a struggle with the release mechanism, he managed to get the canopy open. Hot and soaked with perspiration, Knight somehow removed his own helmet. A ground crewman usually did that for him. But there were no flight support people at his X-15 landing site on this day.

As he attempted to get out of the X-15 cockpit, Knight pulled an emergency release. To his surprise, the headrest blew off, bounced off the canopy and smacked him square in the head. Undeterred, Knight got out of the cockpit and onto terra firma. In the meantime, a Lockheed C-130 Hercules had landed at Mud Lake. Wearily, Pete Knight got onboard and returned to Edwards Air Force Base.

Post-flight investigation revealed that the most probable source of the X-15’s electrical failure was arcing in a flight experiment system. This system had been connected to the X-15’s primary electrical bus. The solution was to connect flight experiments to the secondary electrical bus.

Reflecting on Knight’s amazing recovery from almost certain disaster, long-time NASA flight test manager Paul Bickle claimed the fete was among the most impressive of the X-15 Program. Indeed, it was Pete Knight’s clearly uncommon piloting skill and calmness under pressure that gave him the edge.

Posted in Aerospace, History

A Prelude to Space

Sixty-one years ago this month, USAF Captain Joseph W. Kittinger successfully completed the first Manhigh aero medical research balloon mission. During his 6.5-hour flight, Kittinger reached an altitude of 95,200 feet above mean sea level.

Project Manhigh was a United States Air Force biomedical research program that investigated the human factors of spaceflight by taking men into a near-space environment. Preparations for the trio of Manhigh flights began in 1955. The experience and data gleaned from Manhigh were instrumental to the success of the nation’s early manned spaceflight effort.

The Manhigh target altitude was approximately 100,000 feet above sea level. A helium-filled polyethylene balloon, just 0.0015-inches thick and inflatable to a maximum volume of over 3-million cubic feet, carried the Manhigh gondola into the earth’s stratosphere. At float altitude, this balloon expanded to a diameter of roughly 200 feet.

The Manhigh gondola was a hemispherically-capped cylinder that measured 3-feet in diameter and 8-feet in length. It was attached to the transporting balloon via a 40-foot diameter recovery parachute. Although compact, the gondola was amply provisioned with the necessities of flight including life support, power and communication systems. It also included expendable ballast for use in controlling the altitude of the Manhigh balloon.

The Manhigh test pilot wore a T-1 partial pressure suit during the mission. The garment provided protection in the event that the gondola cabin lost pressure at extreme altitude. The pilot was connected to a variety of sensors which transmitted his biomedical information to the ground throughout flight. This allowed medicos on the ground to keep a constant tab on the pilot’s physical status.

The flight of Manhigh I took place on Sunday, 02 June 1957 with USAF Captain Joseph W. Kittinger as pilot. The massive balloon carrying Kittinger and his gondola was released at 11:23 UTC from Fleming Field Airport, South Saint Paul, Minnesota. In less than 2 hours, Kittinger’s huge balloon reached its design float altitude of 95,200 feet above sea level.

Radio communication problems complicated the Manhigh I mission. While Kittinger could hear the ground, the ground could not hear him. However, the resourceful pilot managed to work around this issue by communicating with the ground via Morse code.

Though balloon, gondola and pilot were functioning quite well, the Manhigh I mission had to be cut short due to rapid depletion of the gondala’s oxygen supply. Post-flight investigation revealed that this anomaly was caused by accidental crossing of the oxygen supply and vent lines prior to the flight.

Kittinger made a safe and uneventful landing near Indian Creek, Minnesota; located roughly 60 nm southeast of the launch site. The recovery crew was quick to the scene and extracted the plucky pilot from the sealed balloon gondola which had fallen over on its side. The official mission elapsed time (MET) was recorded as 6 hours and 32 minutes.

The flight of Manhigh I was a significant technical accomplishment that materially contributed to the advancement of manned spaceflight. Indeed, a TIME Magazine article, entitled “Prelude to Space” and dated 17 June 1957, captured the essence of the achievement. A man had been subjected to space-equivalent physiological conditions for a protracted period, had functioned well in that environment, and then returned safely to earth without ill effect.

For his significant efforts during the Manhigh I mission, Captain Joseph W. Kittinger received the USAF Distinguished Flying Cross.

Posted in Aerospace, History

Final Flight: XB-70A Valkyrie

Fifty-two years ago this month, XB-70A Valkyrie Air Vehicle No. 2 (62-0207) and a NASA F-104N Starfighter (N813NA) were destroyed following a midair collision near Bartsow, CA. USAF Major Carl S. Cross and NASA Chief Test Pilot Joseph A. Walker perished in the tragedy.

On Wednesday, 08 June 1966, XB-70A Valkyrie Air Vehicle No. 2 took-off from Edwards Air Force Base, California for the final time. The crew for this flight included aircraft commander and North American test pilot Alvin S. White and right-seater USAF Major Carl S. Cross. White would be making flight No. 67 in the XB-70A while Cross was making his first. For both men, this would be their final flight in the majestic Valkyrie.

In the past several months, Air Vehicle No. 2 had set speed (Mach 3.08) and altitude (74,000 feet) records for the type. But on this fateful day, the mission was a simple one; some minor flight research test points and a photo shoot.

The General Electric Company, manufacturer of the massive XB-70A’s YJ93-GE-3 turbojets, had received permission from Edwards USAF officials to photograph the XB-70A in close formation with a quartet of other aircraft powered by GE engines. The resulting photos were intended to be used for publicity.

The mishap formation, consisting of the XB-70A, a T-38A Talon (59-1601), an F-4B Phantom II (BuNo 150993), an F-104N Starfighter (N813NA), and an F-5A Freedom Fighter (59-4898), was in position at 25,000 feet by 0845. The photographers for this event, flying in a GE-powered Gates Learjet Citation (N175FS) stationed about 600 feet to the left and slightly aft of the formation, began taking photos.

The photo session was planned to last 30 minutes, but went 10 minutes longer to 0925. Then at 0926, just as the formation aircraft were starting to leave the scene, the frantic cry of Midair! Midair Midair! came over the communications network.

Somehow, the NASA F-104N, piloted by NASA Chief Test Pilot Joe Walker, had collided with the right wing-tip of the XB-70A. Walker’s out-of-control Starfighter then rolled inverted to the left and sheared-off the XB-70A’s twin vertical tails. The F-104N fuselage was severed just behind the cockpit and Walker died instantly in the terrifying process.

Curiously, the XB-70A continued on in steady, level flight for about 16 seconds despite the loss of its primary directional stability lifting surfaces. Then, as White attempted to control a roll transient, the XB-70A rapidly departed controlled flight.

As the doomed Valkyrie torturously pitched, yawed and rolled, its left wing structurally failed and fuel spewed furiously from its fuel tanks. White was somehow able to eject and survive. Cross never left the stricken aircraft and rode it down to impact just north of Barstow, California.

A mishap investigation followed and (as always) responsibility (blame) for the mishap was assigned and new procedures implemented. However, none of that changed the facts that on this, the Blackest Day at Edwards Air Force Base, American aviation lost two of its best men and aircraft in a flight mishap that was, in the final analysis, preventable.

Posted in Aerospace, Final Flight, History

Walking Around the World

Fifty-three years ago this week, Gemini Astronaut Edward H. White II became the first American to perform what in NASA parlance is referred to as an Extra Vehicular Activity (EVA). In everyday terms, we simply call it a “spacewalk”.

White, Mission Commander James A. McDivitt and their Gemini spacecraft were launched into low Earth orbit by a two-stage Titan II launch vehicle from LC-19 at Cape Canaveral Air Force Station, Florida. The Gemini-Titan IV (GT-4) mission clock started at 15:15:59 UTC on Thursday, 03 June 1965.

On the third orbit, less than five hours after launch, White opened the Gemini IV starboard hatch. He stood in his seat and mounted a camera to capture his historic space stroll. He then cast-off from Gemini IV and became a human satellite.

White was tethered to Gemini IV via a 15-foot umbilical that provided oxygen and communications to his EVA suit. A gold-plated visor on his helmet protected his eyes from the searing glare of the sun. The spacewalking astronaut was also outfitted with a hand-held maneuvering unit that used compressed oxygen to power its small thrusters. And, like any good tourist, White also took along a camera to photograph the event.

Ed White had the time of his all-too-brief life in the 22 minutes that he walked in space. The sight of the earth, the spacecraft, the sun, the vastness of space, the freedom of movement all combined to make him excitedly exclaim at one point, “I feel like a million dollars!”.

Presently, it was time to get back into the spacecraft. But, couldn’t he just stay outside a little longer? NASA Mission Control and Commander McDivitt were firm. It was time to get back in; now! He grudgingly complied with the request/order, plaintively lamenting: “It’s the saddest moment of my life!”

As Ed White got back into his seat, he and McDivitt struggled to lock the starboard hatch. Both men were exhausted, but ebullient as they mused about the successful completion of America’s first space walk.

Gemini IV would eventually orbit the Earth 62 times before splashing-down in the Atlantic Ocean at 17:12:11 GMT on Sunday, 07 June 1965. The 4-day mission was another milestone in America’s quest for the moon.

The mission was over and yet Ed White was still a little tired. But then, that was really quite easy to understand. In the time that he was spacewalking outside the spacecraft, Gemini IV had traveled almost a third of the way around the Earth.

Posted in Aerospace, History

IX. SPACE

Fifty-seven years ago this month, President John F. Kennedy boldly proposed that the United States conduct a manned lunar landing before the end of the 1960’s. The President’s clarion call to glory was delivered during a special session of the United States Congress which focused on what he called “urgent national needs”.

The transcript of that historic speech given on Friday, 25 May 1962 indicates that the ninth and last issue addressed by President Kennedy was simply entitled SPACE. The most stirring and memorable words of that portion of the 35th President’s long ago address to the nation may well be these:

“I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth. No single space project in this period will be more impressive to mankind, or more important for the long-range exploration of space; and none will be so difficult or expensive to accomplish.”

Although he did not live to see the fulfillment of that monumental goal, history shows that 8 years, 1 month, and 26 days later, the United States of America indeed landed men on the moon and returned them safely to the earth before the decade of the 1960’s was concluded.

Mission Accomplished, Mr. President.

Posted in Aerospace, History

Spaceman in the Arena

Fifty-six years ago to the day, Mercury Astronaut M. Scott Carpenter orbited the Earth three times aboard his Aurora 7 Mercury spacecraft. In doing so, Carpenter became the second American to reach Earth orbit.

Project Mercury was America’s first manned spaceflight program. A total of six (6) flights took place between May of 1961 and May of 1963. The first two (2) flights were suborbital missions while the remainder achieved low Earth orbits. In February of 1962, John H. Glenn, Jr. became the first American to orbit the Earth during the Mercury-Atlas 6 (MA-6) mission.

Deke Slayton was to fly the Mercury-Atlas 7 (MA-7) mission. However, before that happened, the dreaded flight surgeon cabal grounded Slayton for what they deemed was a heart murmur. Despite Slayton’s utter incredulity and vehement protests, the decision held. Project Mercury officials maintained that the space program could ill afford the negative political fallout occasioned by the death of an astronaut on-orbit.

With Slayton grounded indefinitely, NASA selected Malcom Scott Carpenter to pilot the Mercury-Atlas 7 mission. Carpenter was member of the Original Seven selected by NASA for the Mercury Program in 1959. He was well prepared for the flight since he had just trained as Glenn’s MA-6 backup. As was the practice at that time, Carpenter named his Mercury spacecraft. The appellation he gave his celestial chariot was Aurora 7.

The launch of MA-7 took place on Thursday, 24 May 1962 from LC-14 at Cape Canaveral, Florida. Lift-off time was 12:45:16 UTC. Ascent performance of the stage-and-a-half Atlas D booster was nearly flawless as it inserted Aurora 7 into a 140-nm x 83-nm elliptical orbit. Having been cleared for at least 3 orbits, Carpenter quickly got down to the business of spaceflight.

Much of the activity on the first and second orbits involved Carpenter maneuvering his spacecraft, conducting scientific experiments and observing the Earth from space. Among other discoveries, he discerned that John Glenn’s mysterious “fireflies” were simply particles of ice and frost that had accumulated on the shadow side of the spacecraft. When the spacecraft structure was bumped or vibrated, these particles would disperse from the external surface of the spacecraft and float away into space. Once in the presence of strong sunlight, the particles appeared to glow or be luminescent.

A combination of the astronaut’s spacecraft maneuvering and an intermittently malfunctioning pitch horizon scanner left Carpenter with less than half of his maneuvering fuel left at the start of the third and final orbit. Carpenter compensated admirably by barely using his thrusters during Orbit 3. Indeed, nearing the time of retro-fire, Aurora 7 still had 40 percent of his fuel remaining in both the manual and automatic flight control systems.

As retro-fire approached, the intermittent pitch horizon scanner malfunction reappeared at a most inopportune moment. The automatic stabilization and control system suddenly would not hold Aurora 7 in the proper attitude for retro-fire; heat shield 34 degrees above the horizon at zero yaw angle. Carpenter subsequently switched to manual mode in an attempt to align the spacecraft properly for retro-fire.

When nominal time for retro-fire came, the retro-rockets did not automatically ignite. Carpenter had to do that manually. But he was 3 seconds late. Worst, Aurora 7 was still yawed 25 degree to the right. And to top it off, retro-thrust was 3 percent low. All of this meant that Aurora 7 would overshoot the nominal landing point by 215 nautical miles.

The trip down through the atmosphere was sporty in that Carpenter ran out of attitude control system fuel early during the descent. This meant that there was no means to propulsively damp the side-to-side oscillations that the Mercury spacecraft normally exhibited during reentry. These oscillations became dangerous when they exceeded about 10 degrees. That is, the spacecraft could tumble end-over-end if left unchecked.

Carpenter simultaneously eyed the altimeter and spacecraft angle-of-attack. As the latter built-up dangerously, his only recourse was to manually fire the drogue earlier than planned in attempt to arrest Aurora 7’s oscillatory motion. He did so at 25,000 feet. The spacecraft’s side-to-side oscillations were stopped. Carpenter then deployed his main parachute at 9,500 feet. Splashdown occurred at 17:41:21 UTC at a point 108 nautical miles northeast of Puerto Rico.

Since Aurora 7 was listing badly and help was about an hour away, Carpenter extricated himself from the spacecraft and deployed his life raft. While a radio beacon helped recovery forces locate him, there was no voice communication between the astronaut and his rescuers. Carpenter was on the surface of the briny deep nearly 3 hours before being picked-up by rescue helicopters and safely delivered to the carrier USS Intrepid. Some six (6) hours later, Aurora 7 was brought onboard the USS John R. Pierce.

Mercury-Atlas 7 was Scott Carpenter’s only space mission. A combination of factors, including less than amicable relations with Mercury Mission Control management, led to this being the case. During the intervening years, many stories alluding to pilot error or inattention as the cause of Aurora 7’s landing overshoot have been circulated. Indeed, much like Gus Grissom’s experience with the loss of his Liberty Bell spacecraft, these stories and explanations have been around long enough that they are now accepted as the “truth”.

Criticism of another’s performance comes easily in this world. However, as Theodore Roosevelt once pointed out, it really is “The Man in the Arena” who counts most. It is he and he alone who faces and reacts to the actual moment of trial. No one but he knows the true nature of the reality of that moment and the vicissitudes thereof. While others may criticize, we go on record here to acknowledge and honor M. Scott Carpenter for his heroic and pioneering contributions to early American manned spaceflight.

Posted in Aerospace, History

Project Mercury Finale

Fifty-five years ago today, NASA Astronaut Leroy Gordon Cooper successfully returned to earth after completing 22 orbits of the home planet. Designated Mercury-Atlas No. 9 (MA-9), Cooper’s flight was the final orbital space mission of the fabled Mercury Program.

Cooper’s eventful space mission began with lift-off from Cape Canaveral’s LC-14 at 13:04 hours UTC on Wednesday, 15 May 1963. Splashdown of his Faith 7 spacecraft occurred 70 miles southeast of Midway Island in the Pacific Ocean on Thursday, 16 May 1963. Mission total elapsed time was 34 hours 19-minutes 49-seconds.

While the first 19 orbits of the MA-9 mission were mostly unremarkable, the final three orbits severely tested Cooper’s mettle and piloting skills.

By the time that he manually initiated ripple-firing of the retro motors at the end of the 22nd orbit, Cooper was flying a dead spacecraft. The electrical system was not functioning, the environmental control system was saturated with carbon dioxide, and even the mission clock was inoperative. Temperatures in the spacecraft exceeded 130F.

Cooper had to align his spacecraft for retro-fire using the horizon as a reference, used a watch for timing, and manually operated the reaction control system to counter dangerous spacecraft oscillations during the retro burn.

Cooper also manually controlled Faith 7 during entry and initiated deployment of the drogue and main parachutes.

Incredibly, Cooper landed within 5 miles of the recovery ship USS Kearsarge. In so doing, he established the record for the most accurate landing in the Mercury Program. Gordon Cooper was the last American astronaut to orbit the Earth alone.

Posted in Aerospace, History

Saving America’s Skylab

Forty-five years ago this month, Astronauts Pete Conrad, Joe Kerwin and Paul Weitz became the first NASA crew to fly aboard the recently-orbited Skylab space station. Not only would the crew establish a new record for time in orbit, they would effect critical repairs to America’s first space station which had been seriously damaged during launch.

Skylab was America’s first space station. The program followed closely on the heels of the historic Apollo lunar landing effort. Skylab provided the United States with a unique space platform for obtaining vast quantities of scientific data about the Earth and the Sun. It also served as a means for ascertaining the effects of long-duration spaceflight on human beings.

A Saturn IVB third stage served as Skylab’s core. This huge cylinder, which measured 48-feet in length and 22-feet diameter, was modified for human occupancy and was known as the Orbital Workshop (OWS). With the addition of a Multiple Docking Adapter (MDA) and Airlock Module (AM), Skylab had a total length of 83-feet.

Skylab was also outfitted with a powerful space observatory known as the Apollo Telescope Mount (ATM). This unit sat astride the MDA and was configured with a quartet of electricity-producing solar panels. The OWS had a pair of solar panels as well. The entire Skylab stack weighed 85 tons.

The Skylab space station (Skylab 1) was placed into a 270-mile orbit using a Saturn V launch vehicle on Monday, 14 May 1973. Upon reaching orbit, it quickly became apparent that all was far from well aboard the space station. The micro-meteoroid shield and solar panel on one side of the OWS had been lost during ascent. The other OWS solar panel was stuck and did not deploy as planned.

With the loss of an OWS solar panel, Skylab would not have enough electrical energy to conduct its mission. The station was also heating up rapidly (temperatures approached 190 F at one point). The lost micro-meteoroid shield also provided protection from solar heating. Sans this protection, internal temperatures could rise high enough to destroy food, medical supplies, film and other perishables and render the OWS uninhabitable.

NASA engineers quickly went to work developing fixes for Skylab’s problems. A mechanism was invented to free the stuck solar panel. A parasol of gold-plated flexible material, deployed from an OWS scientific airlock, was then fashioned and tested on the ground. This material would cover the exposed portion of the OWS and provide the needed thermal shielding.

The onus was now on the Skylab 2 crew of Conrad, Kerwin and Weitz to implement the requisite fixes in orbit. On Friday, 25 May 1973, the Skylab 2 crew and their Apollo Command and Service Module (CSM) were rocketed into orbit by a Saturn IB launch vehicle. They quickly rendezvoused with Skylab and verified its sad condition. It was time to get to work.

The first order of business was to try to free the stuck solar panel. As Conrad flew the CSM in close proximity to Skylab, Kerwin held Weitz by the feet as the latter leaned out of the open CSM hatch and attempted to release the stuck solar panel with a pair of special cutters. No joy in spaceville. The solar panel refused to deploy.

The Skylab 2 crew next attempted to dock with Skylab. They tried six times and failed. The CSM drogue and probe was not functioning properly. The crew had to fix it or go home. With great difficulty, they did so and were finally able to dock with Skylab. The overriding objective now was to enter Skylab and successfully deploy the parasol thermal shield.

With Conrad remaining in the CSM, Kerwin and Weitz sported gas masks and cautiously entered Skylab. The temperature inside of the OWS was 130 F. Fortunately, the air was found to be of good quality and the pair went to work deploying the thermal shield through a scientific airlock. The deployment was successful and the temperature started to slowly fall.

It would not be until Thursday, 07 June 1973 that the stuck solar panel would finally be freed. On that occasion, Conrad and Kerwin donned EVA suits and spent 8 hours working outside of Skylab. Their initial efforts with the cutters were unsuccessful.

Undeterred, Conrad and Kerwin improvised and were able to cut the strap that restrained the solar panel. Then, heaving with all their might, the pair finally freed the solar panel. In obedience to Newton’s 3rd Law, as the solar panel deployed in one direction, the astronauts went flying in the other. Happily, they were able to collect themselves and safely reenter the now adequately-powered Skylab.

Skylab 2 went on to spend 28 days in orbits; a record for the time. This record was quickly eclipsed by the Skylab 3 and Skylab 4 crews which spent 59 and 84 days in space, respectively. Skylab was an unqualified success and provided a plethora of terrestrial, solar and human factors data of immense importance to space science. These data played a vital role in the design and development of the ISS.

Skylab was abandoned following the Skylab 4 mission in February of 1974. The plan at the time was to later reactivate the station and raise its orbit using the Space Shuttle when the latter became operational. Unfortunately, a combination of a rapidly deteriorating orbit and delays in flying the Shuttle conspired against bringing this plan to fruition. Skylab reentered the Earth’s atmosphere and broke-up near Australia in July of 1979.

Posted in Aerospace, History

Freedom in Space

Fifty-seven years ago this week, United States Navy Commander Alan Bartlett Shepard, Jr. became the first American to be launched into space. Shepard named his Mercury spacecraft Freedom 7.

Officially designated as Mercury-Redstone 3 (MR-3) by NASA, the mission was America’s first true attempt to put a man into space. MR-3 was a sub-orbital flight. This meant that the spacecraft would travel along an arcing parabolic flight path having a high point of about 115 nautical miles and a total range of roughly 300 nautical miles. Total flight time would be about 15 minutes.

The Mercury spacecraft was designed to accommodate a single crew member. With a length of 9.5 feet and a base diameter of 6.5 feet, the vehicle was less than commodious. The fit was so tight that it would not be inaccurate to say that the astronaut wore the vehicle. Suffice it to say that a claustrophobic would not enjoy a trip into space aboard the spacecraft.

Despite its diminutive size, the 2,500-pound Mercury spacecraft (or capsule as it came to be referred to) was a marvel of aerospace engineering. It had all the systems required of a space-faring craft. Key among these were flight attitude, electrical power, communications, environmental control, reaction control, retro-fire package, and recovery systems.

The Redstone booster was an Intermediate Range Ballistic Missile (IRBM) modified for the manned mission. The Redstone’s uprated A-7 rocket engine generated 78,000 pounds of thrust at sea level. Alcohol and liquid oxygen served as propellants. The Mercury-Redstone combination stood 83 feet in length and weighed 66,000 pounds at lift-off.

On Friday, 05 May 1961, MR-3 lifted-off from Cape Canaveral’s Launch Complex 5 at 14:34:13 UTC. Alan Shepard went to work quickly calling out various spacecraft parameters and mission events. The astronaut would experience a maximum acceleration of 6.5 g’s on the ride upstairs.

Nearing apogee, Shepard manually controlled Freedom 7 about all 3 spacecraft axes. In doing so, he positioned the capsule in the required 34-degree nose-down attitude. Retro-fire occurred on time and the retro package was jettisoned without incident. Shepard then pitched the spacecraft nose to 14 degrees above the horizon preparatory to reentry into the earth’s atmosphere.

Reentry forces quickly built-up on the plunge back into the atmosphere with Shepard enduring a maximum deceleration of 11.6 g’s. He had trained for more than 12 g’s prior to flight. At 21,000 feet, a 6-foot drogue chute was deployed followed by the 63-foot main chute at 10,000 feet. Freedom 7 splashed-down in the Atlantic Ocean 15 minutes and 28 seconds after lift-off.

Following splashdown, Shepard egressed Freedom 7 and was retrieved from the ocean’s surface by a recovery helicopter. Both he and Freedom 7 were safely onboard the carrier USS Lake Champlain within 11 minutes of landing. During his brief flight, Shepard had reached a maximum speed of 5,180 mph, flown as high as 116.5 nautical miles and traveled 302 nautical miles downrange.

The flight of Freedom 7 had much the same effect on the country as did Lindbergh’s solo crossing of the Atlantic in 1927. However, in light of the Cold War struggle against the world-wide spread of Soviet communism, Shepard’s flight arguably was more important. Indeed, Alan Shepard became the first of what author Tom Wolfe called in his classic book The Right Stuff, the American single combat warrior.

For his heroic MR-3 efforts, Alan Shepard was awarded the Distinguished Service Medal by an appreciative nation. In February 1971, Alan Shepard walked on the surface of the Moon as Commander of Apollo 14. He was the lone member of the original Mercury Seven astronauts to do so. Shepard was awarded the Congressional Space Medal of Freedom in 1978.

Alan Shepard succumbed to leukemia in July of 1998 at the age of 74. In tribute to this American space hero, naval aviator and US Naval Academy graduate, Alan Shepard’s Freedom 7 spacecraft now resides in a place of honor at the United States Naval Academy in Annapolis, Maryland.

Posted in Aerospace, History
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