Boeing vs Space X: the race to low orbit | Science | The USA Print


The launch of the new Starliner crewed capsule, carried out at 6:54 p.m. Eastern time in the US (00:54 a.m., Spanish peninsular time) this Thursday, is the second attempt to certify Boeing’s effort to compete with Space X in the transportation of astronauts to orbit. The first was at the end of 2019, when both companies were neck and neck in that race. But then the mission did not go well. The Starliner (baptized Calypso, like Jacques Cousteau’s research vessel) entered orbit, but failed to dock with the International Space Station. problems of software.

It took a year and a half to solve all the problems that the first version of the capsule presented. The second flight was planned for the summer of 2021, but when everything seemed ready and the vehicle was already on the launch pad, a new problem was discovered: 13 of the propulsion system valves were stuck.

The cause of the problem was attributed to the near tropical climate of Cape Canaveral. Not because of the moisture itself, but because the water vapor reacted with a component of the fuel (nitrogen tetroxide) to produce nitric acid. It corroded the Teflon on valve seals and metal parts until they seized. The repair was so labor intensive that Boeing decided to replace the entire propulsion module. If it had been a car, it was like changing the whole engine.

Apart from the cost of the repair, Boeing had to hire a new rocket to repeat the launch. In total, about 600 million dollars for a project that was losing the race against Elon Musk’s company. The Space X capsule is now fully approved for manned missions: it has flown four crews to the Space Station plus a couple of charter flights for private clients.

Abandoning the use of Russian Soyuz capsules, NASA has established contracts with both companies to cover “taxi” services to the Space Station. Boeing got the lion’s share: $4.4 billion for six flights; Space X is much cheaper, thanks to the fact that it uses its own recoverable rockets: 3,500 million for nine launches.

The current mission is essentially an engineering test. It does carry some cargo to the ISS: a couple of hundred kilos of supplies, but the real goal is to verify that it can assemble automatically and that, once attached to the station, there will be no serious incompatibilities.

Automatic encounter is a technique that the Russians have mastered for more than 50 years. Its Progress freighter shipments, first to the Mir station and then to the ISS, are already routine operations. Instead, the Americans have always preferred astronauts to direct the operation manually. Only the Space X Dragons and now the Starliner are prepared to do so without pilot intervention.

Being a very delicate maneuver, all precautions are few. The Space Station is surrounded by a series of virtual spheres in which no vehicle is allowed to enter until all its systems have been verified to be working properly. The first covers three kilometers around the ISS; the second, two. The “prohibited passage” is 200 meters. All capsules must stop there before receiving final clearance for docking. If you are curious about how this last phase is carried out, Space X offers a very realistic simulator. on this website. Plays pretty much the same software carried by astronauts aboard Dragon capsules.

Both Starlink and Dragon are designed for low orbit operations. For longer trips, to the Moon, for example, the Orion will be used, which someone defined as “an Apollo on steroids” due to its resemblance to the lunar ship of the sixties.

Orion’s maiden flight may take place in June, though that’s not certain, as the carrier rocket has yet to pass its leak test. It is about filling your fuel tanks at very low temperatures. The cold causes the sheet metal to shrink and reveal cracks that would otherwise be unnoticeable. This is what happened a few weeks ago, when the rocket and capsule had to be returned to the assembly building for repairs.

Raphael Clement He is an industrial engineer and was the founder and first director of the Barcelona Science Museum (now CosmoCaixa). He is the author of ‘A small step to [un] man’ and ‘The other Apollos’ (Dome Books).

You can follow MATTER in Facebook, Twitter and Instagramor sign up here to receive our weekly newsletter.


Please enter your comment!
Please enter your name here