 You know what's more futuristic than the jetpacks who were promised in the 1960s? Jetpacks on the moon! And we almost saw them as part of the later Apollo missions. Hello everyone, I'm Amy. Welcome to the Vintage Space, my little corner of the internet where we talk about all things mid-century that fascinate me, many of which are space-based, like lunar jetpacks. But before we dive in, or rock it in, let's take a look at the need for mobility when exploring the lunar surface. The Apollo lunar surface missions had limitations. The biggest was consumables in the lunar module. The spacecraft could only support two men for up to three days, so that was the longest the astronauts could possibly stay on the surface. Their EVAs or moonwalks were also limited by what they could hold in their backpacks, properly the Apollo Portable Life Support System. The PLSS is what turned the lunar EVA suits into little wearable spacecraft, giving the astronaut inside oxygen, water for drinking and cooling, as well as power they needed for the suit's systems, including communications with each other and mission control on Earth. Each EVA was planned to maximize the use of those consumables, because once their power was low and their oxygen levels were low, the astronauts had no choice but to go back to the lunar module. There was another limitation to how much the astronauts could explore. It was easy to get lost. If they lost sight of the lunar module, there was nothing to tell them in this foreign lunar terrain how to get back to the lunar module. All this meant that a landed crew could only explore the area close to the lunar module. But there was interest in getting a look at features and sites further than a stone's throw from where they landed. NASA did want to get good science out of these missions, after all. Extending the astronauts' ability to cover ground thus became a goal for later Apollo missions, once the actual landing had been accomplished. NASA started researching mobility aids in the summer of 1967, but it wasn't until early 1969 when the first lunar landing was imminent and longer lunar stays around the corner that the agency finally started pursuing actual hardware. One leading idea was personal flying units. NASA awarded two lunar flying unit study contracts, one to Bell Aero Systems and one to North American Rockwell, a company that was also building the command service module. Fleshed out bids came back to the space agency after five months. Bell wasn't new to the idea of personal flying systems when NASA awarded its study contract. In addition to some early research with the agency, the company had developed its own rocket belt. This was a wearable hydrogen peroxide propulsion system that provided 300 pounds of thrust and made more than 3,000 successful demonstration flights. Bell built off its prior experience for its lunar flying system. Its proposal called for the astronaut to stand on a little platform supported on four legs similar to those on the lunar module, so basically a small stool. There was no seat, but with the lower lunar gravity, legs would be excellent shock absorbers. It was the same rationale Grumman had used when designing the lunar module with the astronauts standing at the controls. Safety straps helped anchor the astronaut in place in front of a central console where the controls were housed. The controls were similar to those in the lunar module. The astronaut operated a handle. His inputs activating two throttleable engines mounted on either side of the console. The engines were designed to generate between 50 and 300 pounds of thrust, which in the lower lunar gravity was more than enough to listen astronaut in his EVA suit along with an array of instruments and tools. Following NASA's own guidelines, the fuel tanks feeding the engines would be filled from excess hypergolic propellant from the lunar module's descent stage. Once landed, that stage served as a launch pad for the ascent stage, so siphoning off the excess fuel was just making good use of existing mission supplies. Grumman even built an extra fuel allowance into the stage for safety. On a nominal mission, there could be anywhere between 300 and 1,500 pounds of propellant left after landing. To get the flyer to the moon, Bell designed it to fold into one of the storage bays in the lunar module's descent stage where the crew could recover it and set it up like they did all their surface instruments and experiments. And in an ideal setup, a mission would carry two of these flying platforms, one for exploration and one as a backup should something fail. In the event one astronaut took the flyer out and got stuck, his crewmate could take the backup out to recover him. Adding a pallet would turn the one-man flyer into a two-man flyer. Bell's proposal anticipated later versions that could carry a heavier payload. It even imagined modifying the system to carry astronauts on Mars or in an emergency serve as rescue vehicles if the lunar module's ascent engine failed. Bell put the total cost at $29.2 million in 1969 with operational readiness slated for 1973. MUSIC North American system was also a four-legged platform similar to Bell's, also designed to fold into the lunar module's descent stage for storage on the way to the moon. But instead of side-mounted engines, this proposal called for a cluster of four engines at the vehicle's center of gravity, each of which could generate up to 105 pounds of thrust. Right above that engine cluster was a shock-absorbing seat. This setup did two things. First, it added stability to the vehicle, making it potentially safer for the operator. Second, because the engines were centrally mounted, if one failed, the system could still fly on three. The downside was that the engines being mounted lower on the flyer increased the risk of regolith and rocks getting kicked up to potentially do some damage. North American's solution was a special fabric launch pad. The astronaut could lay this blanket down, pull the flyer on top of it, then take off. He'd have other pieces of the same material with him, so he could fly to some distant spot. For a safe landing, he would just have to cut the engines early to avoid kicking up dust during his descent. After he'd explored the area, he could lay out his spare launch fabric, drag the flyer over top of it, and take off again. North American system weighed about 1,075 pounds, but in the moon's lower gravity, it was fully reasonable for the astronaut to drag it onto that launch platform. The North American's proposal didn't have a backup or emergency orbit capability like Bell's did. It did have a higher altitude capability, 2,000 feet compared to Bell's proposed 100 feet. This meant the system could give the astronauts a better lay of the land and send them to interesting spots on hillsides while still keeping them close enough to walk back to the lunar module if something failed. As we know, neither proposal yielded anything that went to the moon. In October of 1969, NASA awarded a contract to Boeing to build a lightweight car astronauts could drive on the moon. The Apollo lunar roving vehicle, or more commonly known simply as the lunar rover, was, like the proposed flying platforms, stored folded in the lunar module's descent stage. I have a video about how that worked right up here. It went from contract to flight readiness in less than two years, making its debut on Apollo 15, which launched on July 26th of 1971. And the rover made a huge difference. On Apollo's 11, 12 and 14, crews covered a total combined distance of 4.4 miles on foot. With the help of the lunar rover, and in part because these later lunar missions had longer stays on the moon, Apollo 15 covered 17 miles and Apollo 16 covered 16.8 miles. On the last mission, Apollo 17's Gene Cernan and Jack Schmidt drove the furthest from the lunar module four and a half miles away and covered a total of 22.2 miles. I hope you guys enjoyed this little look at lunar technology that never flew. That is going to do it for me for today. I want to remind you guys that my two books Fighting for Space and Breaking the Chains of Gravity are indeed available however you like to consume books. I've got links to both in the description below. I also want to say a very special thank you to my Patreon supporters and YouTube members. You guys truly make it possible for me to continue creating this content, so thank you so much for your continued support. I want to thank each and every one of you for spending a little bit of your day here with me, and I'll see you next time.