Elon Musk spoke at the MIT Aeronautics and Astronautics Department’s 2014 Centennial celebration. The October 22-24 Centennial Symposium featuring some of the most illustrious names in aerospace reflecting on past achievement, celebrating today’s innovative research and education, and offering their perspectives on what lies ahead.
SpaceX CEO Elon Musk said his company will make a first attempt to land the booster stage of its Falcon 9 rocket on a floating platform during the upcoming ISS resupply mission. If the attempt is successful, the company plans to refurbish and reuse the booster stage, making spaceflight history and paving the way for a significant reduction in the cost of access to space.
Propellant only makes up a tiny percentage (in the case of a Falcon 9 rocket, about 0.3 percent) of the cost of the craft, so being able to reuse all the hardware for multiple flights could potentially slash the cost of spaceflight by a factor of 10 or more.
SpaceX and Tesla CEO Elon Musk has said that, on the fifth resupply mission planned for December 9th, the reusable rocket program is ready to go one step further: instead of a soft water landing, the first stage will attempt for the first time to propulsively land on a floating platform in the middle of the Atlantic Ocean.
“Before we boost back to the launch site and try to land there, we need to show that we can land with precision over and over again,” said Musk. “So for the upcoming launch we’ve got a chance of landing on a floating platform. We have a huge platform that is being constructed at a shipyard in Louisiana right now which is 300 feet long by 170 feet wide (90 by 50 meters).”
“If we land on that [platform], I think we’ll be able to refly that booster,” Musk continued. “It’s probably not more of a 50 percent chance of landing it on the platform [on the first try], but there’s a lot of launches that will occur over the next year, at least a dozen, so I think it’s quite likely, probably 80 or 90 percent likely, that one of those flights will be able to land and refly.”
The steerable fins provide control during fly back. They can be seen deploying about a minute and 15 seconds into the flight. This test flight of the Falcon 9 Reusable (F9R) occurred on June 17th, 2014.
There was an analysis of a reusable launch system where the cost of developing the reusable launch system was $36 billion. If Spacex is successful they will have developed reusability for about $100 million.
“The payload penalty for full and fast reusability versus an expendable version is roughly 40 percent,” Musk says. “[But] propellant cost is less than 0.4 percent of the total flight cost. Even taking into account the payload reduction for reusability, the improvement is therefore theoretically over a hundred times.”
A hundred times is an incredible gain. It would drop cost for Musk’s Falcon Heavy rocket—a scaled-up version of the Falcon 9 that’s currently rated at $1000 per pound to orbit—to just $10. “That, however, requires a very high flight rate, just like aircraft,” Musk says. “At a low flight rate, the improvement is still probably around 50 percent. For Falcon Heavy, that would mean a price per pound to orbit of less than $500.
Falcon Heavy is particularly amenable to reuse of the first stage—the two outer cores in particular, because they separate at a much lower velocity than the center one, being dropped off early in the flight.
Bringing down the cost of rocket launches isn’t just about reusability; as Musk’s quote suggests, it’s also about turnaround time. The original premise of the space shuttle program was that the vehicle would be turned around within days; it ended up being months, which is one of the reasons that it never met its cost goals.
What about a reusable Falcon? Musk says he expects “single-digit hours” between landing and next flight, at least for the lower stages. “For the upper stage, there is the additional constraint of the orbit ground track needing to overfly the landing pad, since cross-range [the distance to a landing site that it can fly to either side of its original entry flight path] is limited. At most this adds 24 hours to the upper-stage turnaround.”
Translation: One of the other reasons that the shuttle was so expensive was that it had very large wings to give the vehicle a thousand miles of cross-range. The Air Force demanded this feature, which would have allowed the shuttle to return to its launch site after a single orbit, though it was never used. But SpaceX doesn’t mandate that cross-range feature. Therefore its craft would have to wait a little bit for the Earth to rotate and bring the landing site around again, but this would make SpaceX missions cheaper because the rockets don’t have to carry so much propellant in this stage.
What does it imply for flight rate? “Multiple flights per day for first stage and side boosters,” Musk says. “At least one flight per day for the upper stage” (which costs much less, anyway).
So what does that mean for ticket prices in the future? Musk tells us that with daily flights, the cost will run about $100 per pound. For the average male, that means about 20,000 bucks. Start saving your money.
Is there demand for forty thousand flight per year ? 100 space flights per day at $100 per pound ?
Those launches were for about $2000-8,000 per pound.
There are new far more capable cubesats. Having a lot of lower cost payload would boost demand for low cost launches.
Planetary Resources is making $1 million space telescopes.
Bigelow Aerospace wants to launch inflatable space stations for space hotels and for space stations for every nation with a space program.
Daily launches of one reusable rocket is 365 launches. If you have 100 reusable rockets all flying daily then you need demand for 36,500 launches. If the payload capacity is 8 to 50 tons. This would be 180,000 tons to 1.8 million tons.
There would be need for more launch facilities.
There would need to be a system for rapidly prepping the payloads. Some kind of standard container system for loading them. A space version of a shipping container.