New plans and new problems with the NASA SLS rocket

New plans and new problems with the NASA SLS rocket https://i1.wp.com/www.eresviral.com/wp-content/uploads/2018/10/1539572807_Nuevos-planes-y-nuevos-problemas-con-el-cohete-SLS-de-la-NASA.png?fit=260%2C146&ssl=1

New plans and new problems with the NASA SLS rocket







All of NASA's manned space projects for the next few decades have one element in common: the SLS rocket and the Orion spacecraft. Of these two elements depends the future Gateway lunar station and the proposed manned travel nebula to Mars from 2030. Tax by the Congress to the Obama administration after the cancellation of the Ares V of the Constellation Program, the SLS (Space Launch System) had not accumulated too many delays in his, on the other hand, slow and expensive development. But in recent years the term SLS has become synonymous with delays and cost overruns. First 2017 was considered as the date for the first launch, but shortly thereafter it was delayed to 2018 and then at the end of 2019. Currently no one expects it to take off before the beginning of 2021, although NASA still officially maintains the June 2020 date of face to the public.



The SLS Block 1 (NASA).



In the middle of this year NASA also decided to confirm the change in the dates of introduction of the different versions of the SLS. Recall that this rocket comes in three variants: Block 1, capable of placing a minimum of 70 tons in low orbit, Block 1B, with capacity for 105 tons, and Block 2, which may be up to 130 tons in LEO. The difference between Block 1 and Block 1B is that the first one uses the ICPS as a second stage (Interim Cryogenic Propulsion Stage), while Block 1B must make use of the EUS (Exploration Upper Stage). In principle the Block 1 version should only be used in the first mission of the SLS, the EM-1 (Exploration Mission 1), which will launch the Orion around the Moon. However, NASA has changed its mind and will use it in at least two more missions, including the first manned mission of the system, EM-2.



Variants of the SLS (NASA OIG).





Rocket SLS Block 1 (NASA).



This decision aims to give more time to improve and lighten the EUS, which was already beginning to accumulate delays in a dangerous way, and, in passing, also gives the agency more time to build a second service tower. The tower that is currently under construction caused a small political earthquake last February when it was learned that it would cost more than 900 million dollars and that the works to make it compatible with the Block 1B version would force to delay the launching of the second mission of the SLS several years. The government authorized last spring the construction of the second tower that will allow to launch the SLS Block 1B from the ramp 39A of the Kennedy Space Center, so it will no longer be necessary to modify the current tower for the missions of this version. The problem is that now we have to certify the ICPS stage for manned flights for the EM-2 mission, which is going to be more headaches.



Stage Cryogenic Propulsion Stage (ICPS) for the SLS based on the second stage of Delta IV Heavy (NASA).





Modifications of the tower for the Block 1B version (right) (NASA).



Anyway, NASA plans to carry out the second mission of SLS Block 1 in 2022. In this mission the Europa Clipper probe will be launched to Jupiter, while in 2023 the third Block 1 will take off in the EM-2 mission, which will take four astronauts around the Moon aboard the Orion ship. The Block 1B version equipped with the EUS stage will debut in 2024 in the EM-3 mission, which will launch a manned Orion along with two modules of the Gateway lunar station. These modules (the module of use of NASA and the European module SPRIT) will be coupled to the PPE propulsion module that will have been previously launched in 2022 by means of a conventional vector. The new NASA calendar allows to develop a lighter EUS that will be able to increase the payload of a lunar trajectory by approximately two tons. In return, this new scheme requires launching the EUS on a manned mission without having been tested before.



Mission EM-1 (NASA).





Emblem of the EM-1 (NASA).



But if NASA thought that with this new plan the problems of the program were going to disappear, it was wrong. In a recent audit, the management of NASA and the role of the main contractor of the SLS, which is none other than Boeing, is criticized very harshly. The report blames the multinational for the main delays and cost overruns, including embarrassing episodes such as the faulty installation of the world's largest welding machine - for the central stage of the SLS - in which the characteristics of the soil were not taken into account. placed. The audit is devastating with Boeing in terms of its role in the construction of the central stage («We found Boeing's poor performance is the main reason for the significant cost increases and schedule delays to developing the SLS Core Stage»), But also criticizes other aspects that are the responsibility of NASA.



This is for now the only completed element of the central stage of the SLS of the EM-1 mission (NASA).



The fact is that NASA has spent 11,900 million dollars in the SLS. And Boeing will have to spend a total of 8.9 billion until 2021 for the system to be operational. That is, twice the number initially planned. And that's not to mention the delays and problems associated with the Orion ship, which are not exactly few. The management of the SLS seems to be out of control, but no one considers the cancellation of the project, which is too important to be dropped. However, NASA must take drastic measures if it does not want the first mission of the SLS to be forever three years in the future.

Expected missions of the SLS:



Early 2022 (officially June 2021): EM1 mission of the SLS Block 1 with an unmanned Orion spacecraft around the Moon.

2022: loading mission of the SLS Block 1 with the Europa Clipper probe.

2023: EM-2 mission in an SLS Block 1. First manned mission in the system.

2024: manned mission EM-3 with elements of the Gateway station. First flight of the Block 1B version with the EUS stage.



References:



https://oig.nasa.gov/docs/IG-19-001.pdf

        .

  !function(f,b,e,v,n,t,s)

  {if(f.fbq)return;n=f.fbq=function(){n.callMethod?

  n.callMethod.apply(n,arguments):n.queue.push(arguments)};

  if(!f._fbq)f._fbq=n;n.push=n;n.loaded=!0;n.version='2.0';

  n.queue=[];t=b.createElement(e);t.async=!0;

  t.src=v;s=b.getElementsByTagName(e)[0];

  s.parentNode.insertBefore(t,s)}(window, document,'script',

  'https://connect.facebook.net/en_US/fbevents.js');

  fbq('init', '369524843414444');

  fbq('track', 'PageView');

    .


SOURCE LINK ERESVIRAL.COM 
https://www.beviral.online