The Angry Alligator on Gemini 9A

"The answer is not throwing away the fairings or even trying to catch them.
The best way is to never get rid of them in the first place
- Peter Beck


These days we've got so many rocket launch startups all striving to bring their launch vehicles to fruition, but sometimes it feels as though they've all roughly converged to the same general design. Obviously I know each has their nuances, like Relativity's 3D printing and Astra's barebones architecture, but at least visually they all look more or less the same: two stage configuration, RP-1/LOX engines, conical fairing, etc. But once in a while, a new rendering pops up that makes me do a double take, like, "Oh man, they're really gonna try build that thing, that's wild!" 

So when I saw the fairing design on Rocket Lab's upcoming Neutron rocket, you can bet I was pretty excited! Unlike a typical rocket where the upper stage is stacked on top of the booster, Neutron is planning to encapsulate the ENTIRE second stage within the surrounding booster. And rather than jettisoning the nose cone after passing through the atmosphere, the unique four-petal fairing will simply hinge open to release the second stage. Already affectionately dubbed "the hungry hippo", this design will hopefully eliminate the cost of recovering and refurbishing the fairing separately from the first stage

I see the hippo, but honestly what it reminds me of is the Piranha Plant from Super Mario!

And yet, while Rocket Lab's design is daring and innovative, as soon as I saw the rendering I knew I'd seen something similar from an old NASA mission. Sure enough, I found it: the Augmented Target Docking Adapter on Gemini 9A!

By 1966, the buildup to the moon landings was well underway; Project Mercury had proven human beings could successfully operate in orbit, and now NASA needed Gemini to demonstrate longer duration spaceflights and more complex maneuvers like rendezvous and docking. But Gemini 9A was beset with problems right from the start; the original crew was supposed to be Elliot See and Charles Bassett, but just four months before the mission, both men were killed in a plane crash. The two astronauts were flying from Texas to inspect the Gemini spacecraft being constructed by McDonnell Aircraft in St. Louis, but poor visibility due to rain and fog combined with pilot error on the part of See caused them to miss the runway and crash their T-38 Talon into the side of one of the McDonnell buildings, killing them instantly. Despite their tragic demise, the plane crash didn't damage the spacecraft or cause any other delays to the mission, so NASA pressed forward and moved the backup crew of Thomas Stafford and Eugene Cernan to the prime crew

Prime crew in front, backup crew in rear

The initial objective of Gemini 9 was to dock with the Agena Target Vehicle (ATV) that would be launched separately ahead of the crew. Gemini 8 had done something similar, but that mission was aborted promptly after docking when a stuck thruster sent Neil Armstrong and David Scott spiraling out of control, nearly killing them. Unfortunately, any hope of Gemini 9 improving upon 8 was quickly dashed when the Atlas rocket launching 9's ATV malfunctioned, sending the spacecraft crashing back down to Earth. NASA quickly scrambled and launched the backup Augmented Target Docking Adapter (ADTA), then replanned Stafford and Cernan's mission to dock with the ADTA instead, renaming the mission from Gemini 9 to Gemini 9A. Once the ADTA was safely in orbit, Stafford and Cernan then blasted off into orbit on their Titan II rocket and rendezvoused with the ADTA

A fantastic illustration of the original Agena Target Vehicle (ATV) above and the replacement Augmented Target Docking Adapter (ADTV) below

As Stafford and Cernan drew closer to the ADTA, they saw to their dismay that the fairing halves had failed to separate, preventing them from docking. With the two conical pieces jammed ajar, Stafford commented, "it looks like an angry alligator out here rotating around." It was apparent that the fairing's explosive bolts had fired, but there were loose electrical wires tied to two steel bands that were still holding the fairing halves together. The astronauts brainstormed ways to resolve the problem with Mission Control, but every solution they came up with was deemed way too risky: if they sent Cernan out on an EVA to cut the wires, they were afraid the sudden release of tension would whip out dangerous wiring and sharp edges that could easily puncture his spacesuit. Stafford even asked if they could ram the ADTA with the Gemini capsule to try force the fairings to open, but Mission Control ruled it out, fearing they would damage their spacecraft

The reason for the faulty wiring was quickly discovered: multiple miscommunications and last-minute design changes to both the ADTA and the Atlas rocket resulted in the fairings being installed by a crew of McDonnell technicians completely unfamiliar with the design, rather than the Douglas and Lockheed crew as originally intended. And even though there had been a Douglas engineer on-site contracted by NASA to certify the installation, the McDonnell crew refused to let him inspect their work despite the protests of both NASA and Douglas

The jammed fairings on the ADTA, as seen from Stafford and Cernan's Gemini capsule

With the ADTA docking abandoned, Stafford and Cernan focused on the other mission objective: the Air Force had designed the Astronaut Maneuvering Unit (AMU), which was essentially a jetpack that Cernan was supposed to test out during an EVA. Cernan began preparing for his spacewalk, but after pressurizing his suit, "the suit took on a life of its own" and became so stiff that it moved like "a rusty suit of armor." As he struggled to climb outside towards the back of the spacecraft, he quickly became exhausted as his heartrate skyrocketed to 180 bpm, so much so that the flight surgeon was afraid he would pass out

At this point everyone knew it would've been incredibly risky to proceed to with the AMU test. Not only was Cernan exhausted, but his spacesuit's cooling system had been completely overwhelmed, and as Cernan overheated his suit visor fogged up entirely. Stafford ordered him to abandon the test and get back inside, and after Cernan miraculously managed to get back to the cockpit area blind, Stafford literally had to grab onto his legs and help cram him and his overpressurized spacesuit back into the hatch

Cernan in the middle of his incredibly challenging spacewalk with the AMU, which you can see on the right during pre-flight testing

Fortunately for the tired crew, finishing the EVA was the last of their travails as their reentry was smooth and precise. Post-flight medical examination found Cernan had lost an astonishing 13 pounds during the spaceflight, and when they sent his spacesuit back to Houston, there was "about a pound or a pound and a half of water in each boot" worth of sweat! 

While not quite successful, NASA still learned many valuable lessons from Gemini 9A. Later Gemini missions were able to dock far more successfully, and the Apollo spacesuit switched to a more robust water-cooled design rather than Gemini's air-cooled spacesuits, which proved extremely effective for the astronauts that walked on the moon!

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