As you may know, in 2018 ESA will launch its satellite, Solar Orbiter, with the purpose of studying our Sun more closely. Above Earth had the chance to meet and interview Claire McCrorie, British Engineer working for Airbus Defense and Space, the company responsible for the satellite construction.
Solar Orbiter’s mission
With the aim to understand more about our Sun, Solar Orbiter’s purpose is to study the heliosphere and how it works but also to learn more about solar activity.
The heliosphere is a « bubbule of gas » generated by the solar wind (atomic particle projection). The solar wind is responsible for magnetic storms and also the aurora borealis that you can see on Earth.
To perform its mission, Solar Orbiter will travel to the Sun with a closest approach of a record 42 million kilometres. Because of the many and varied science instruments it carries, it will analyse the sun like no one before.
The Solar Orbiter spacecraft is divided into two main parts :
The Spacecraft « platform » (picture on your left), wich hosts the Payload.
The Payload (picture on your right) which is the part with all the scientific instruments wich perform the experiments.
Claire McCrorie, who is working on Solar Orbiter, was kind enough to answer our questions.
Interview by Cyril Plou for © Above Earth.
Claire, can you introduce yourself in few lines ?
My name is Claire McCrorie and I work for Airbus Defence and Space near London, in the UK. My ‘official’ job title is Solar Orbiter Operations and FDIR architect. I’ve been with the company for 15 years, starting off in Portsmouth (on the south coast of England) where I worked on both navigation and telecommunications spacecraft, and then moving to Munich where I worked on the first Galileo satellites, Galileo being the European satellite navigation system.
Can you explain what is your job exactly?
My responsibilities are two-fold. Firstly I’m responsible for the operations of the spacecraft. This means that I have to write the user manual – just as when you buy a TV, a spacecraft comes with a user manual. This is provided to the operators in order to allow them to fly the spacecraft. ESOC – the European space agency’s operations centre in Darmstadt in Germany will operate Solar Orbiter. The user manual consists of a description of the spacecraft – what it looks like mechanically and thermally, but more importantly what the software does and how the data on-board flows – how do the equipment talk to each other, how do we make the solar arrays move so they don’t get too hot, how do we move the antennas to allow them to communicate with Earth.
In addition to the user manual, we provide what we call flight control procedures. These are the procedures that the operators follow when flying the spacecraft. They will consist of a sequence of steps including commands to be sent to the spacecraft and then checks of information coming back from the spacecraft to confirm that the commands were successful and that everything is ok on-board. The procedures are used for nominal operations, so the things that are necessary to ensure that the mission is carried out – management of the data and memory stores, switch on and configuration of the science instruments, movement of the solar arrays and antennas, as well as how to recover from failures and put the spacecraft back into a nominal safe configuration.
The second part of my job involves something called FDIR. This stands for failure detection, isolation and recovery. Once a spacecraft is launched obviously it’s very difficult to fix if it goes wrong (unless you are the Hubble and you send the space shuttle!), therefore we try to ensure, by design, that we can recover failures autonomously by clever software. Firstly we ensure that almost all of the units on-board have ‘spares’, therefore if one breaks we have another to use. Then we analyse each equipment to determine what the likely failures are. We find the best way to detect those failures – by pieces of information provided by the unit, or by other units, and then we design software which monitors that information and when it shows something has gone wrong implements an on-board procedure which switches off the failed equipment and uses the other one. We therefore ensure that the spacecraft is always safe. My job is therefore to design this failure management concept and ensure that it is correctly implemented in software.
All procedures and tools you put in place are tested later, is that there are often surprises and what they are due in general?
We test as far as possible on Ground – the procedures that we use for flying the spacecraft are either tested on the spacecraft on ground, or where that’s not possible then we test them on a simulator. That way we are confident that everything we have designed works.
Having said that, there are always surprises! As I mentioned before when we look at failures we do an analysis to determine what is likely to go wrong, but usually once in space we find that it’s something completely different, or a combination of different things happen at once leading to a situation we could never have imagined! But that’s what keeps the job exciting, and if we have a solid operational and failure management concept we can always find a way to solve the problem and recover nominal spacecraft operation.
All internal instruments of the probe are built by several different EU countries, you get to assemble them? Is working with different countries for the same project complicated from a technical point of view ?
It certainly has its challenges! There are 10 instruments on Solar Orbiter and of course they all operate a little bit differently – no matter how hard you try to standardise data interfaces and other aspects there’s always going to be some variation if you have 10 different teams in many many different countries. But it keeps the job interesting, and it means that no two days are ever the same!
The middle of the engineering and astrophysics is a sector where there are a lot of men, is it difficult for a woman to “make” her place?
I haven’t found it too difficult. I started with physics and maths classes at school where I was one of very few girls, and then university was the same. For me it’s become normal to be in the minority. But I have found the space industry to be open and accepting and although it’s true that I often see surprise on people’s faces when I don’t fit the typical mould for a space engineer, it has always turned quickly to acceptance when it’s clear that I can do my job just as well as they can
Have you always wanted to work in the sector or is it coincidence?
I pretty much always wanted to do it. I wanted to fly in the navy when I was younger, but my eyesight wasn’t good enough. So, next best thing to flying planes was designing them. I was good at physics and maths so applying to study aeronautical engineering seemed logical. And then when studying there were a few courses on space systems towards the end – and you can’t help but be excited by learning about space. So, I went on to do a post grad in ‘Astronautics and Space Engineering’. Once you’ve done that there’s really no option but a career in the space industry..!
Un immense merci à Claire pour son temps et ses explications !!
A great thank’s to Claire for her time and her explanations !