• Question: Did u ever help working on a rocket?

    Asked by Star2006 to Eimear, James, Jonathan, Lána, Willi on 27 Feb 2018.
    • Photo: Lána Salmon

      Lána Salmon answered on 27 Feb 2018:

      Rockets are really cool. I unfortunately haven’t worked on any – I have learned the equations for how they get off the ground and how they use planets to propel them in different directions! Our satellite, EIRSAT-1, will hopefully fly on a rocket in 2020 to the International Space Station. That will be really cool. Willi, who is also on the EIRSAT-1 team, has worked on rockets. I’ll let him tell you about what he does, and how his work will be used on EIRSAT-1 to stabilise the satellite in the same was as his work helps to stabilise rockets!

    • Photo: William O'Connor

      William O'Connor answered on 27 Feb 2018:

      One of my projects is working on ways to control rockets (we call them “launchers”).
      We are specialising in how to control the launcher when it is not very rigid (that is, it is a bit wobbly). Why is it wobbly? Because you want the rocket itself to be as light as possible, and if it is light, then it is not very rigid, and can bend and vibrate.
      An extra complication is that there is usually liquid fuel on board, and it can start “sloshing”, that is, moving from side to side, like when you carry a basin of water it can start sloshing.
      When it is going up, a rocket is like balancing a brush on your finger. You are pushing at the bottom, and if you don’t do it right, it will fly all over the place, like a balloon when the air is coming out the back.
      So the control system needs to be clever, to keep the rocket going on the right path (“trajectory”), while also controlling any tendency to sway or slosh or do any kind of dance.

    • Photo: Eimear Tuohy

      Eimear Tuohy answered on 27 Feb 2018:

      No. I just work with the data the satellites send back to the ground stations.

    • Photo: James Geary

      James Geary answered on 27 Feb 2018:

      Yes, I have worked on the design and development of the Ariane 5, Ariane 6 and Vega launchers. For Ariane 5 I worked for an Irish company called Devtec that designed and developed mechanical supports for the cryogenic engine Vulcain from SEP in France.

      I did some of the early phase A development support to Ariane 6. On big development projects we split the activities into phases and put gates between the phases as design reviews in order to access if the project is ready to pass to the next phase.

      The following are the phases used by ESA:
      Phase A: Feasibility phase to establish if a mission is possible
      Phase B: Definition phase setting the missions key requirements
      Phase C: Development phase establishing the design and supporting justifications e.g. analysis and test
      Phase D: Production phase is building the system
      Phase E: Deployment phase is launch and operations

      I supported some anomaly investigations on Vega during the development phase linked to welding porosity on a component.

      Now I mostly work on spacecrafts but have to liaise with the launch authority in the preparation of the launch safety submission. This document outlines the main design and build characteristics of the spacecraft that you are wishing to launch on a spacecraft and also details all related hazards e.g. type of propellant, operations at launch site before launch.

      The launch authority will need to approve this document before you receive the authorisation for launch on their spacecraft. For Ariane 5 the French government also approve the document as the launching state is also liable after lift off.