Redbull hangár

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2011. december 12., hétfő

House of applied sciences – My visit at Joanneum university’s aviation department in Graz

III. part

Text and phtos: Gabriella

In the first and the second part of the Joanneum report, you could read about the development of an unmanned aerial vehicle and the flight simulator among other things. This is the spectacular side of study aviation, but students need the theoretical principles, like applied maths and physics and strong knowledge in the field of avionics. And how does it connected to such topics like commercial flights without pilots and the catastrophe of the Brazilian Air France flight? You will learn by the end of this post.

Dr. Messnarz and the basics

If you read the first part of my report, you have already met Dr. Bernd Messnarz’s name. He is responsible for the university’s flight simulator and teaches applied maths and physics among others. Sounds too abstract? Check our conversation and you will learn its practical side.

Gabriella: Applied mathematics and physics are mysterious fields for an ordinary person. Could you explain to me with concrete examples why it is important to learn it to the students?
Bernd Messnarz:  When our students start the aviation, they are not primarily interested in mathematics or physics, so it is a very important point to tell them in the first or second semester what is good, for example the logarithm or in physics the Newton laws for example. I always try to give examples what will be the application of a mathematically technique later on.



In teaching I have this picture and the topic is the cockpit of an Airbus 380 and the students know, that there is a lot of flight control and a lot of computing in there. It begins with a lecture which called Flight Control Systems, but at the beginning, the basic here is physics, the famous axioms of Newton which is the basis of flight control system. It governs all the mechanics. Then you also need the physics and also the mathematics here, where we deal with differential equations later on. The next step is informatics, because they use computing to do numerical calculations. This is the way up to the flight engineering, let’s say.

G: In my translation, it means to me, that future pilots must know the basics too, because they cannot belong to computers completely, because there can be situations where they need the basic knowledge. That’s why seems to me crazy that idea of the big boss at Ryanair, that only one pilot is enough on a flight, because an advanced flight control could do everything and the pilot should just supervise it. What is your opinion about it?
BM: It’s possible to be enough. An aircraft would be able to fly without a pilot in future, but it’s more mental reason to have the pilots. But if there are some unforeseen events, the computer cannot react. A program can only react what is programmed for, but if there an unexpected event, you need a human operator. But a computation point of view, aircrafts can fly alone even nowadays. It can automatically take off and land.

G: You mentioned the mental reasons as an obstacle. If you think of yourself, would you trust in just a computer as a passenger sitting on an airplane?
BM: No, not really. But you also need to trust in a computer already today, because they overtook so many tasks and are very much involved in flying.

G: And even a pilot cannot avoid every accident.
BM: Yes, just remember the famous Air France flight which fell down above the Atlantic in 2009. Because of the icing of the pitot tubes, the sensors got wrong signals and even the pilot could not solve the situation.

G: One of my pilot friends told me, that at this concrete event, the captain should have known the solution, but there was something of a chaos in the cockpit and didn’t do that maneuver which could have helped.
BM: Maybe the training is not good today, they should train the pilots more to avoid such events like this. For example, that they don’t trust the machine that much.

The quadrocopter



G: Are you involved in the JXP project?
BM: No, but I can tell you more about a project with the micro UAV. Before we was going to build the JXP with a span width of 7 meters and weight with 23 kg, we knew, that we cannot test the flight algorithm with a big airplane. So we have here this model or this RC aircraft, but equipped this with electronics and can fly totally autonomously. We have sensor on it, there is the pitot to the velocity and inside is the autopilot routine, which is equipped with sensors to measure the altitude. The altitude is also measured by barometric. The students built it within their project. At the beginning of this year we had the first autonomous flight on that field which is opposite the laboratory. The plain flied on circles autonomously, only with GPS control. It has crashed at our last test (we tried out something which was not successful), so we have to build it up again, but as it costs only 90 EUR so won’t be that expensive and the electronics still works.
Our other project is the quadrocopter, which can also fly totally autonomously, equipped with a lot of sensors (for example a GPS) then this is the magnetic sensor and beside there is the inertial measurement. This is on the front side of the quadrocopter. You can program this with weight points and GPS grid points and it would hold a certain position in the air. You can mount a camera for example on a road crossing and you can use the picture of the camera to count the traffic which can be interesting for the engineers who design the motorways. It can hold its position in the air if there is windy or dusty. Its vario is stable like in a helicopter. Comparing it with a fixed wing aircraft, it’s much easier to test the quadrocopter, because you go outside and just start it, but when you have a fixed winged aircraft, you always have to look for a bigger place. This is its main advantage for us here. And for example when we collect GPS data or something like that from the flight trajectory, I can also use this data to informatics lesson. I tell them about this project and we have real data which we collect ourselves. Because when students work on this project, they are in their fifth or sixth semester.

Professor Flühr  - present and future of avionics

Professor Holger Flühr teaches avionics and it definitely seems to me, that he loves his chosen field. As it has turned out by the end of our chat, it is a very rich topic.


Professor Flühr in the middle (photo: FH Joanneum)

Holger Flühr: First of all, it is necessary to stress that although “avionics” means mainly the electric devices on the aircraft, also all the electronics on ground has to be covered, too. The cockpit electronics relies to the systems on the ground and they interact heavily.  Think of a flight from point A to point B: the pilot needs navigation systems to know where he is and where to fly. This interaction is ensured by navigation systems on the ground and the equipment on board. On the other hand, if you think of an air traffic controller sitting in the tower at an airport, he needs information on air traffic around the airport and the surrounding airspace. It is mandatory to know all the aircraft, all the flights within a certain airspace. This information is provided by the systems on ground, the radar systems. So, on one hand, all the systems we need inside an aircraft are covered by the topics of avionics, and so are the ground systems necessary to navigate an aircraft or for surveillance of the airspace. These systems are covered in my lectures and in our research work.

Gabriella: Does teaching avionics mean lifelong learning even to the teacher taking account the fast innovation of this industry?
HF: Definitely. We teach some very basic technologies - this is what we deal with during the first semesters, from the beginning of the studies. Then we have advanced topics where technology can make progress very fast. So it’s a very broad range of aspects. We try to build a bridge of knowledge for our students, so they have knowledge on the basic principles and they should use it to understand the more advanced systems. This is my basic idea how to things can set up during our studies.

G: Joachim told me, that you wrote a book recently about avionics. Could you tell me more about it?
HF: The book (“Avionik und Flugsicherungstechnik”, Springer-Verlag, 2010) is mainly about air traffic control technology and it’s a very broad approach to this subject. On one hand it is dedicated to our students, it should help them to better understand what they hear about during the lectures. But it is also dedicated to engineers who would like to start working in the aviation industry. I can give you an example from my background. I started electric engineering and biomedical engineering which is completely different from aviation. When I started with FH JOANNEUM almost nine years ago, I found it rather difficult to find good literature as a starting point to get familiar with the aircraft systems used in aviation. My opinion is: the technology in the background of aircraft systems is the same as with commercial electronic systems. What is completely different is the regulatory framework. You have a lot of regulations, a lot of legalization and all these things are not known to electronic or mechanic engineers. The book targets to overcome this issue. It should give a good base, a good understanding on how the aviation industry works, while focusing to the electronic aspects.

G: What do you think about the future of avionics? What can be de main directions in the field of development?
HF: There are several directions which can be seen even today. There is a big trend called “all electric aircraft”. It’s known, that kerosene won’t be available in 50 or 100 years from now. There’s an ongoing research to find out how an aircraft has to be configured in the future to get the same performance as today – but without relying on kerosene, with using hydrogen or other means to the aircraft. Such an aircraft will mainly consist of electronic systems. There could be a fuel cell, there could be an electrical-driven propeller which powers the aircraft and most systems will be powered in an electrical way in the future, too. The same direction can be seen in the automotive industry with electro mobility.
The other actual thing today is the improvement of the European air navigation system. Today, European airspace is divided in many small sectors compared with the US airspace, which is rather one big sector. This is something which will change in the future, there’s currently a big research project called “Single European Sky ATM Research (SESAR)” financed by the EU. This will change air traffic management dramatically in the future. There will be new technologies available for communications, for navigation, and for surveillance. I think, the complete airspace will look different in let’s say 20 years from now.
On the aircraft electronics side, I think modern systems like computer networks will be much more present in the aircraft of tomorrow. Most likely there will be separated high-speed networks both in the cockpit and in the cabin for the passengers’ convenience.  The aircraft network will be connected to a network on the ground, everything will be integrated into an overall “aviation” network.

G: I have already asked Dr. Messnarz about the following question and I would be eager to your opinion too. What do you think about commercial flights without pilots?
HF: From a technical point of view, it would be possible today. We already have airports where such systems are present today, e.g. for automated landings. You can drive from A to B by autonomously operating trains. The security of the system can be ensured by technology. But from a psychological point of view, it is problematic. I think, that most people would avoid choosing an airline using such an approach.

G: The number of flights is growing constantly all over the world and the airports are more and more crowded. Air traffic is getting a difficult task to handle day by day. Do you think, that there will be improvements on this field too?
HF: I think, it’s a future field for research. And it is necessary, because there is big need for improvements e.g. in environmental protection. It’s known, that the air traffic will increase in the future due to the increase of the industries in China, India, Brazil and so on.  So there is a big demand for additional air traffic in these regions. There will be a 5 or 6 % growth in the next years and this leads to the point, where we have to figure out how to set up the system in the future to be environmental friendly, avoiding noise when approaching to or departing from an airport. There are many issues open for research.

G: Do you have a favorite topic in the field of avionics?
HF: My background is communications engineering, so I’m really interested in new system to communicate let’s say between an aircraft and ground station. One of my research topics   is dealing with systems for unmanned aircraft. We are developing a communication system which is very reliable and robust to ensure the communication from a ground station to unmanned aircraft, even under worst circumstances.

The JXP prototype (photo: FH Joanneum)

G: Is it part of the JXP project?
HF: Mid to long term, it is going to be implemented in the JXP, yes. In the first step, we target to test the system on ground. For this, we have a test bed, which is located in our lab. Here, we use a small model of an aircraft with movable flaps. Our developments are getting connected to that model to prove the systems work correctly and to show that it is a safe and reliable technology. In the second step, we will most likely use a rotorcraft, Mr Messnarz’s quattrocopter, or another micro UAV which could carry the communications equipment to be tested. After the second step, we will implement it to JXP and the long term goal could be that the JXP can be flown completely autonomously.

G: Could you tell me exact example to the bad communication between the ground station and the aircraft which can be improved?
HF: The most critical points of the communication between ground and aircraft are A: not reliable, B: not secure. Today, everybody can monitor the communication between the air traffic controllers and the pilots using a FM radio. When you think of an airport, there could be a security risk today, which is not really known to the public. Somebody could buy a portable transmitter and could try to talk to the pilot or the controller, which is of course prohibited by law. This could eventually lead to dangerous situations. It’s an old technology, amplitude modulation which is used in aeronautical communications was implemented in the mid of the last century. Compared with modern digital communications systems like GSM mobile phones or WLAN, it’s a very unsecure mean of communication. We target to establish a communication system which operates reliable even under harsh environments and when interferences are present.

G: Is there a communication system what can be reliable even in bad weather conditions?
HF: We have some tricks to improve availability of communication systems under harsh environments.  In many cases interferences are only affecting certain frequency ranges or bands. In our system, we use a redundant approach. We try to use 2 or 3 links in different frequency bands. So in case one system is interfered, the other systems still work in parallel. Then there are modern modulation technologies. It’s a way to code the information which has to be transmitted onto a certain frequency.  Using this technology, the interference can be less strong, than with older systems.
Another possibility would be to implement back-up systems in the aircraft. In that case - if the communication link really got lost - the aircraft “knows” what to do in case of emergency. For example it can fly some circles or it can try to land on a certain place autonomously.

G: Are you involved in the ant-icing research at the university?
HF: Only partially. The topic of icing is not really considered in my working group, but we contributed with a small project. We figured out how a special sensor system behaves under icing conditions. Some years ago there was the Air France accident. Icing of the air data sensors could have contributed to that accident. In this research project, we were working together with a company developing a new kind of air data sensor and we made some test for them to find out how the sensors perform under such conditions. So we used the test equipment and experience of the anti-icing group, we tested the sensor, and we gave some indications to the company for further research.

G: Are there other ongoing projects at the Avionics department which you would like to mention?
HF: We think about a new system of inertial navigation, a system which combines future satellite navigation systems with an inertial navigation system which is working completely autonomously on the aircraft side.  This is one research project which could start in the future.  It could be the case that we look more into optical communications in the future. Such communication systems using infrared light could replace electronic data buses and networks in the future.

In the next and last part of my report, you will learn Simon Jauk and Andreas Tramposch and their research projects. You can get direct information about the other side of life at the university through the interview with a student.

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