You could call the Block 5 the new, improved version of SpaceX’s work-horse, the Falcon 9, and you would be right. In fact, SpaceX CEO Elon Musk says the Block 5 rockets will eventually be able to fly up to 10 times without the need for any maintenance after landings.
The newly minted Block 5 edition of the Falcon 9 is equipped with about 100 upgrades for greater power, safety, and reusability than its Block-4 predecessor, according to Reuters.
After a 24-hour delay of the May 10 debut launch due to “a standard ground system auto-abort” that halted the countdown 58 seconds before liftoff, the Block 5 edition lifted off successfully May 11 at 4:14 p.m.
The Block 5 landed its first stage 11 minutes later on the unmanned platform vessel, “Of course I still love you,” in the Atlantic Ocean and deployed Bangladesh’s first telecom satellite, Bangabandhu-1, to geostationary transfer orbit just under 34 minutes later.
Bangladesh Prime Minister Sheikh Hasina in a livestream appearance from her country’s capital, Dhaka, hailed the successful launch: “Today is a very delightful and glorious day for our motherland, Bangladesh, and Bangalee nation,” she said. “With the launching of Bangabandhu Satellite-1, we are hoisting our national flag in space.”
Learning the lessons from 2016 event
SpaceX had put a great deal of effort into creating very reliable COPVs, or composite overwrapped pressure vessels. COPVs are used to store helium to pressurize the propellant tanks in the launcher’s second stage.
In September 2016, a Falcon 9 exploded during preparations for a static fire test and destroyed a telecom satellite for Israeli fleet operator Spacecom. SpaceX engineers and technicians were able to trace the cause of the explosion to liquid oxygen in the upper stage tank that got trapped between the COPV overwrap and liner and ignited either from friction or other mechanisms.
SpaceX, working with NASA, has worked long and hard to redesign the pressure vessels to address the agency’s concerns about using that design on later Falcon 9 commercial crew launches.
“This is by far the most advanced pressure vessel ever developed by humanity,” Musk said. “It’s nuts. I’ve personally gone over the design; I can’t count how many times. The top engineering minds at SpaceX have agonized over this … I think we are in a good situation.”
The new COPVs now have a “burst pressure” that’s “more than twice what they are actually loaded to on the pad,” says Musk. SpaceX also has a backup plan that involves switching from high-strength carbon fiber with an aluminum liner to the superalloy Inconel, but Musk believes this won’t be necessary.
The Block series Falcon 9 rockets
Basically, the Block 5 will be the rocket used to send astronauts to the International Space Station (ISS) for NASA. But in order to make the Falcon 9 certified for carrying humans, SpaceX had to make a huge number of improvements to the rocket’s design.
“There are thousands and thousands and thousands of requirements,” Musk said. Not only does the space vehicle have to be able to handle more loads during launch – but the tolerance level for small failures has to be much higher. This means very few “small failures” are allowed.
According to Musk, NASA is requiring that the Block 5 be flown at least seven times, without making any major changes to the rocket, before people can ride on it. And don’t think all these changes and requirements haven’t made Musk a bit nervous, either.
“The reason that it’s so hard to make an orbital rocket work is that your passing grade is 100 percent,” he said. “And you can’t fully and properly test an orbital rocket until it launches, because you cannot recreate those conditions on Earth… Man, anyway, I’m stressed.”
But the Block 5 will also be used to launch U.S. Air Force global positioning satellites and other high-value, military and national security payloads. So it looks like the Block series will be kept busy.
But looking ahead, Musk sees the Falcon 9 doing about 300 more launches before it is retired. Then, the bulk of SpaceX’s missions will be done on the company’s next big rocket, the BFR.
