Gathering at the Stratobowl once again, the U.S. Army Corps and National Geographic Society were preparing for a second Explorer expedition. It would be the first of two that were scheduled to occur during the summer of 1935; one set for July, the other for August.
In the February issue of the National Geographic Magazine, the flights were announced, as were the flight crew. Signing on for a second round were Captain Orvil A. Anderson and Captain Albert W. Stevens. Major William E. Kepner would be unable to reprise his role, and was replaced by Captain Randolph P. Williams.
Learning from the first Explorer expedition, an improved balloon design was created, but similar to the first, hydrogen would once again be used. This would end in catastrophe. But the failure would prove to be eye opening, and helped with the success of Explorer II.
Setting the Stage
Through the night of July 11, 1935, the second Explorer balloon was filled with hydrogen. As with the flight of Explorer I, the balloon was set to launch early in the morning. But it would never make it off the ground.
On July 12, as the gondola was being set to be attached, the balloon exploded, ending the expedition abruptly. It would nearly be the end of the Explorer expeditions as a whole. However, the fault in the design was discovered; the rip panel was too large. The designers, Goodyear-Zepplin employees, set out to correct the design flaw, allowing the mission to continue.
But other factors would further delay launch. Throughout rest of the summer, the Stratobowl would lack favorable weather. In order to launch, an absence of wind was needed overnight, as the balloon was inflated, while the day of the launch had to be cloudless, and the ground wind at the landing area couldn’t be more than 15 miles an hour.
It wouldn’t be until November 10 that everything came together. By then, temperatures had dropped in the area, but it was a factor that could be worked through, even though it caused a problem that nearly grounded the mission.
The new balloon, which was considerably larger than the Explorer I balloon, was made of two and two-thirds acres of a new rubberized cotton. Learning from previous mishaps, helium was used to inflate.
Having been stored at around 50 degrees Fahrenheit, as it was spread out for inflation, it quickly began to cool, dropping down to near 0 degrees on the frigid night. As the balloon began to inflate, and grew in size, a tear began to form, which ended up being 17 feet long.
Goodyear-Zepplin technicians, inspecting the rip, decided that it could be safely patched. Using a 2-inch strip of tape, as well as a five-inch patch, which were cemented along the tear, the tear was repaired and the rest of the inflation proceeded without any additional problems.
Ready to Launch
Working by floodlights throughout the night of the 10th, 1,685 cylinders of helium would be used to fully inflate the balloon. Standing in wait to be attached was the new gondola. Like the balloon, the gondola was also larger. In order to reduce weight, only two of the three man crew would take flight in the Explorer II: Anderson would be pilot and Stevens flight commander and scientific observer. Williams would take on ground operations.
At 7:01 a.m., on November 11, the seven-and-a-half-ton Explorer II would launch in front of nearly 40,000 people. Many of them would get a bit of surprise.
As the balloon reached about 200 feet above the ground, a strong wind burst blew it towards the cliffs of the Stratobowl. Immediately, the crew began dumping ballast. Some 750 pounds would pour from the Explorer II, with much of it falling on the heads of spectators. To many on the ground, it would appear as if streams of water were pouring down as it took only three seconds for the ballast to be released.
With the ballast gone, the Explorer II would launch quickly out of the Stratobowl and into the sky. Once they reached 16,000 feet, Anderson and Stevens left the gondola in order to inspect their rigging. Finding no issues, they would reenter, and pressurize the gondola. With everything set, Anderson and Stevens would break records, reaching an altitude of 13.71 miles.
As with Explorer I, the crew stayed in contact with both reporters and the ground below, but the record breaking flight would be downplayed, as one reporter said, “There is still plenty of chance for them to crash and they have to come down alive to make it a record.”
Scientific Study
At such a height, Explorer II was above 96% of all the air in the atmosphere, which allowed them to conduct their primary mission, which was to study the atmosphere and cosmic rays. Carrying sixty-four different scientific instruments, the scientific benefits of the flight wouldn’t be matched until Apollo 8.
Quite possibly the most significant breakthrough that the Explorer II flight made though was that it demonstrated that humans could make it to space, that they could be protected from the environment of the stratosphere. With the flight equipment having been tested, it would give the United States an edge when it was improved on in World War II, and eventually would lead to the success of the space program.
It would also be on this flight that the first photo of the curvature of the Earth, as well as the curved top of the troposphere, were taken. The only hiccup they experienced was when they attempted to turn the capsule once they had reached the peak of their climb.
Using an arm-mounted fan, the goal was to turn the capsule in order to allow their instruments to obtain readings from different directions, but since the air was so thin, they were unable to do so.
Landing
Around noon, Anderson began releasing helium from the balloon, in order to start their descent. For the first 30,000 feet, the descent was gentle, but as they hit around 40,000 feet, where the air density increased, the balloon and its crew began to drop rapidly, at 600 feet per minute.
Describing the landing, Stevens stated: “We donned the football helmets loaned us by the Rapid City School, stretched a safety belt across the gondola, and then as the gondola nearly touched the ground, we pulled together on the ripcord. The top of the bag instantly opened. It deflated so quickly that the gondola turned over on its side. Hanging to the safety rope we swung to the center of the car, while objects of all descriptions, that had been on the floor, hurtled by us. We groped around with our feet and found that we were standing on some of our instruments.”
Finally, the gondola touched down about 12 miles south of White Lake, South Dakota. They had traveled over 230 miles across the state in eight and a half hours, and even though they had a rocky landing, were unhurt. Before Anderson and Stevens could exit the gondola, they were surprised to see eager spectators peering into the portholes.
Thousands of people had been tracking their flight, and as they began to land, they converged on the site. Moments later, members of the Fourth Calvary, from Fort Meade, arrived at the landing site. They would help members from the Civilian Conservation Corps camp at Lake Andes to manage the crowd, and secure the equipment.
It was now official, Explorer II had successfully broken a number of altitude records. But it would also be the end for the Explorer expeditions. While Stevens had wanted to continue the flights, he also acknowledged that they were not only expensive, but risky. Realistically, there also wasn’t much more that could be gained by another expedition in the immediate future.
The information gathered from the mission also had to be analyzed. It wouldn’t be until 1956 that another balloon, as part of United States Navy’s Project Strato-Lab, would be launched from the bowl. That flight, the Strato-Lab I, would reach an altitude of 76,000 feet, setting a new record for a manned balloon flight.
However, that launch would get much less coverage, and would seem to many to be less impressive. Using information from Explorer II, the United States Air Force had already designed planes that were reaching altitudes of 90,000 feet.
Two years after the Strato-Lab I flight, the Explorer name would once again be used. On January 31, 1958, Explorer I, the first United States unmanned satellite, was launched and escaped the earth’s gravity.
Eventually, on July 20, 1969, man would land on the moon. A feat that Captain Stevens wouldn’t have imagined back in 1935. When questioned about flights that could thrust free of earth’s gravity, he had labeled them impossible. But unknown to him, and his crew, the cotton balloon, and metal ball they used to reach up to the heavens, would provide the United States with the data they needed in order to not only escape from earth, but to land on another heavenly body.