NASA Head Tells Why Agency Continues To Develop SLS Heavy Launch Vehicle


Comparison of Falcon Heavy, Saturn V, SLS, and Falcon 9
After Elon Musk developed and successfully tested the Falcon Heavy heavy launch vehicle, NASA was constantly asked uncomfortable questions. They relate to the organization’s own heavy rocket, called the Space Launch System (SLS). The fact is that not only the development of a rocket, but also its launches cost a lot of money. According to some estimates, NASA spends as much on a SLS project a year as would be enough for a couple of dozen Falcon Heavy launches. Even US President Donald Trump, who, in principle, is loyal to the agency, was “price of the matter”.

NASA usually did not answer and did not talk about the reasons for continuing to finance such an expensive project as SLS. But, for example, one SLS launch is now estimated at approximately $ 500 million, while the cost of launching the Falcon Heavy is only $ 90 million. But it was no longer possible to remain silent, so the head of the agency had to give a reasoned and detailed answer to accumulated questions.

The head of NASA’s manned flight division, William Gerstenmeyer, said: “After the Falcon Heavy passed the successful tests, we are constantly asked the question - why, instead of SLS, we will not buy 5-6 SpaceX rockets and will not start working with them. What is the reason that we continue to spend money? ” According to Gerstenmeyer, the reason is in the different capabilities of the missiles. SLS it is capable of bringing up to 26 tons of payload to a lunar orbit, but Falcon Heavy is capable of less - it will “transport” from 18 to 22 tons of cargo to the moon. True, the cost of a kilogram of cargo launched into Falcon Heavy’s orbit is still much lower than that of SLS.

But we are not talking about small loads, when it comes to the moon. According to Gerstenmeyer, large and heavy blocks will be used to build a near-moon orbital station, and here the capabilities of SLS will be very useful. But when the station will be assembled, then the team and cargo to it will be able to deliver Falcon Heavy.


NASA is planning several modifications for SLS, but they will cost just space amounts

It is worth noting that almost immediately a detailed comment was given on this answer. According to third-party experts, people cannot always be in the orbiting lunar station. The fact is that the radiation level there is much higher, and the team will be able to stay at the station for a short time. Well, the orbital station for the Moon itself will be small, they plan to assemble it from relatively small modules, for the launch into space of which the Falcon Heavy capabilities are quite enough. The heaviest module will be the energy one, called the Power and Propulsion Bus. Its mass is only 9 tons. And Falcon Heavy can lift about twice as much, and this is by most conservative estimates.

In a further speech, Gerstenmeyer continued to argue that the main calculation is based on the fact that SLS can output much heavier loads at a time. “We are developing a plan to use SLS as a launch vehicle, which can launch large and bulky cargo into space, putting it all at once,” Gerstenmeyer said. He believes that it is far from always that certain types of cargo can be divided into separate elements in order to bring them to the estimated position in several launches.

In principle, all this is correct, but the problem is that there is no SLS operation plan yet, and it is unlikely to arise in the near future, since NASA simply does not have “monolithic and heavy” cargoes that require SLS. For experts, Gerstenmeyer’s words were not very convincing. As far as you can understand, the agency continues to work on SLS because a lot of money has already been spent, and it will be difficult to explain to the government why the missile, which cost the taxpayers a huge amount, was never built, and there is no special need for this missile.

Some experts believe that the rocket simply “eats” NASA alive, forcing it to allocate more and more funds. Nothing good is likely to end.