25/2022: Fundamentals of Aerospace Engineering Part 2 Ending

 FIFTH CHAPTER: ORIENTATION AND CONTROL IN THREE DIMENSIONS

In this chapter, we will start on a new topic in aeronautical engineering flight mechanics. We'll also provide an overview of spacecraft controllability, suborbital flight profiles, orbital flight vehicles, and also atmospheric flight vehicles like aircraft, etc.

Laws of Motion

A simplified review of the laws of the Three Laws of Motion was proposed by Sir hase Newton in 1665 and they help to explain how an object flies and reaches its destination.

How does this work for a rocket? The force of its powerful engines acts to push down on the ground, and the reaction from the ground pushes the rocket upwards with an equal force. In the next section, we'll derive some equations for a straightforward cruise based on this rule.

Fundamentals of Aerospace Engineering (Beginner's Guide) Orbits are a path around an object in space, so for instance, the orbiter moon is said to und Earth. That's because Earth is orbiting around the Sun. The International Space Station orbits Earth. An object bet is called a satellite. The path of an orbit is curved, somewhere between a circle and an oval, but technically speaking it's called an ellipse. A comet, for example, follows a very long and thin ellipse-sometimes it is close to the Sun and moving quickly, but mostly it is very distant from the Sun and moving slowly. The moon's orbit, on the other hand, is almost circular. Why are there these differences? To find out we'll look at the three laws about the Sun and planets developed by Johannes Kepler (1571-1630). 

1. The Law of Ellipses (The path of the planets about the Sun is elliptical in shape, with the center of the Sun being located at one focus). 

2. The Law of Equal Areas (An imaginary line drawn from the center of the Sun to the center of a planet will sweep out equal areas in equal intervals of time).

3. The Law of Harmonies (The ratio of the squares of the periods of any two planets is equal to the ratio of the cubes of their average distances from the Sun).

Kepler was able to develop these three laws describing the motion of planets in a Sun-centered solar system after studying the data that had been carefully collected by his mentor, Tycho Brahe. Modern science no longer accepts his explanations of the underlying reasons for these orbits, but the actual laws themselves are still accepted as accurate descriptions of what happens.

 

You know now from Newton's First Law of Motion that a moving object will continue moving unless something pushes or pulls on it. So for example, a satellite would fly off into space without gravity, and with gravity, it is constantly pulled back toward Earth. This tug-of-war between its velocity and gravity keeps the satellite in orbit.

Height is how far up something is. Interestingly, objects at different heights orbit at different speeds. The ISS at about 320 km above Earth, must move about 800 kph- and takes about 90 minutes to orbit once around Earth. The Moon, much higher at about 400,000 km from Earth, must move about 3,500 kph - and takes about 28 days to orbit once around Earth. Earth takes a year to orbit the Sun once -but Pluto takes about 248 Earth years to orbit the Sun once!

Moving in Orbits.

When a satellite's speed is balanced by the pull of Earth's gravity, it will hit the Earth but without the speed and gravity balancing each other, it will either fly off into space in a straight line or fall back to Earth. Satellites orbit the Earth at different heights, different speeds, and along different paths. The most common types of the orbit are geostationary and polar.

Sun-synchronous orbit is a nearly polar orbit around a planet, in which the satellite passes over any given point of the plant's surface at the same mean solar time. A geosynchronous orbit (sometimes abbreviated as GSO) is the orbiting earth of a satellite with an orbital period that matches the earth's rotation on its axis, which takes about 23 hours, 56 minutes, and 4 seconds (sidereal day). The term geosynchronous may be used to mean geostationary which is not correct but a common mistake. 

Geostationary orbits, in fact, are orbits in which the satellite is always positioned over the same spot on the earth. Many geostationary satellites are above a band along the equator, with an altitude of 22 thousand miles which is about a fraction of the distance to the moon.

A Low Earth Orbit (LEO) is an earth-centered orbit with an altitude of 2,000 km or less, or with at least 11.25 periods per day and an eccentricity, of less than 0.25 Most of the manmade objects in space are in LEO. Medium Earth Orbit (MEO) in the region of space around earth above low earth orbit and below geosynchronous orbit (as you see in figure 5.3); the orbit is home to several manmade satellites. 

A stationary satellite travels level with the equator from west to the west (Le in the same direction as the spinning Earth) and at the same rate. Consequently, from the Earth, it looks stationary since it always sits above the same location. A polar-orbit satellite travels from pole to pole (i.e. from north to south to north again). It can scan the entire globe, one strip at a time, while the Earth spins underneath it.

Why Don't Satellites Crash Into Each Other? Actually, they can! Because satellites in space are monitored by NASA and other U.S. and international organizations, collisions are fortunately rare. Moreover, each satellite is launched into an orbit designed to avoid other satellites. However, orbits can change over time, and the chances of a crash increase as more and more satellites are launched into space and left to stay there for years at a time. The first and so far only accidental collision between two man-made satellites occurred in February 2009, when two satellites, an American and a Russian, collided high above the planet. Both were totally destroyed.

Sometimes the path and speed of a spacecraft are altered by using the relative movement and gravity of a planet or other astronomical object. This is called a gravitational slingshot, a gravity assist maneuver, or a swing-by. It's usually used to save propellant, time, and expense. Several robotic spacecraft have used this maneuver, so they could reach their targets much further away from the Sun. Voyager 2 was launched in August 1977 and flew by Jupiter for reconnaissance, and for a gravity assist boost so it could Teach Saturn, Voyager 1 was launched the following month, used the same Martinique, and reached Jupiter before Voyager 2. 

Voyager 2 then obtained a gravity amit hot from future and another one later from Uranus, to get all the way to Neptune and beyond Geller got a gravity at boost from Venus and two from Earth, while orbiting the Sun at the way to its destination, Jupiter took two gravity may bonete from Venus, one from Earth, and another from Jupiter to gain enough momentum to reach Saturn.

The gravity mist technique usefully adds or subtracts momentum to spacers orbit It has generally been used in solar orbit, to increase spacecraft's velocity and propel it outward in the solar system, much farther away from the Sun than its launch vehicle would have been capable of Sensex flyby can also decrease a spacecraft's orbital momentum, the Callien special decreased its energy, relative to Jupiter, with gravity assist flyby from the Jovian moon la in this way, it was possible to decrease the mass of tock propellant needed for insertion into a Jupiter orbit. Comets and other bodies in the solar oth naturally experience changes in their orbits, when they pass diose by a planet or a moon

The tarp Voyager spacecraft provide classic examples. They were launched from a Titan-III/Centaur, destined for Saturn and beyond. But they could only reach Jupiter, which is halfway to Saturn. If Jupiter had not been there at the right time, they would have reached aphelion (ie. farthest orbital point) near Jupiter's orbital distance of about 5 AU (ie. 5 Astronomical Units or 750,000,000 km) from the Sun. Their perihelion (ie. nearest orbital point) would have been about Earth's orbital distance of 1 AU (150,000,000 km from the Sun). They would have remained in that orbit until a planet or something else caused it to change.

But of course, their launch times were planned so that Jupiter coasted by at just the right time! The spacecraft felt Jupiter's gravity and started falling toward it. The spacecraft's velocity brought it to close behind Jupiter in its solar orbit, but not close enough for impact. As Voyager traveled away from Jupiter, it slowed down again concerning Jupiter, and eventually reached the same speed it had had on its way in. The spacecraft approaching and departing from Jupiter is like a bicyclist speeding up while going downhill into a valley, and then slowing down again for the uphill road leaving the valley.

This is a vector diagram showing the situation in two simplified dimensions: magnitude of velocity and direction of the velocity. The magnitude and direction of the spacecraft's trajectory on its way towards Jupiter are shown in the lower right. Its magnitude and direction on its way out away from Jupiter are shown in the upper left. You can see that the direction of the spacecraft's velocity has changed because of the accelerating force of Jupiter's gravitation - but not its magnitude.

Note that Vis and Viss represent velocity before and after being noticeably changed by Jupiter's presence. Near the middle of the diagram, the long arrow alert to Jupiter indicates where there's a significant, but temporary, increase in the magnitude (speed) as its orbital direction changes. Note that these speeds are all concerning Jupiter.

Let's look at this in terms of the cyclist again - but ignoring air friction and vehicle friction, etc., as they are virtually absent in the spacecraft's situation. Va shows the cyclist approaching a downhill grade into the valley. Four shows that the cyclist has slowed down again at the top of the ensuing uphill grade. Indeed. After going through the valley, the cyclist's direction might have changed, but in the end, there's been no lasting change in speed. However, for someone watching this from beyond Jupiter's perspective something else has happened.

In the cartoon, the child sees his tennis ball moving away from him at 50 kph. So does the Sun, sitting on the station platform. The engineer driving the train sees the ball coming at 100 kph since the train is moving 50 kph concerning the ground. The train and ball interact at 100 kph. The ball rebounds from the front of the train at nearly the same 100 kph, but this can be added to the 50 kph speed of the train, which it acquired from the frame The result, seen by a stationary observer, approaches a total of 150 kph. In the same way, the velocity of a spacecraft is added to the velocity of the massive spending planet, so it "rebounds'' with an even higher velocity in the case of the spacecraft though, it is a gravitational, rather than a mechanical interaction that this to happen.

Suborbital Flight Mechanics

In outer space, suborbital flight mechanics, equation derivations and the basics are the same as they are for atmospheric flight, the only difference being that in outer space there's no atmosphere and no significant drag above 24,500 m. Flights are similar too, but during the planned, but not executed, Lynx Mark 1 (XCOR) flight, for example, participants would have experienced an exhilarating profile. rocket ride to space, out-of-this-world views, and the feeling of weightlessness. In the daytime, the sky would have been black and the Earth's curvature along with the thin blue line of the atmosphere would have been visible.

After re-entry, participants would have continued to enjoy this view until they descended to lower altitudes before landing on the same runway where the space plane had taken off from. Figure 5.8 below provides a graphic overview of the planned flight profile,

When the California-based company XCOR Aerospace was in the race competing in the emerging suborbital spaceflight market, they were developing the XCOR Lynx a suborbital horizontal-takeoff, horizontal-landing (HTHL), rocket-powered spacecraft It was planned that the Lynx would carry one pilot, one ticketed passenger, and/or a payload above a 100 km altitude. In March 2014, the passenger ticket was projected to cost $95,000.

At the time, the XCOR Lynx Space Flight vehicle's stats were remarkable. It was to have broken the sound barrier and flown supersonic 58 seconds after taking off. Immediately after take-off, it was to have climbed at a 75° angle with a constant push of 3Gs, Its maximum speed during space flight was to have been Mach 29 or 3,550 kph (2,200 mph). After 3 minutes of rocket-like acceleration, the Lynx spacecraft was to have reached 58 km and then switched off its engine. It would still have had enough speed to reach the maximum of 103 km (338,000 ft) in about another 1.5 minutes. The view the passengers would have had up there would have been absolutely stunning. The whole trip would have been an experience never to be forgotten. As the astronauts say: it's that view back to Earth that changes lives.

The Lynx flights were to have started in 2014 from Curacao (in the Caribbean) and the Mojave Desert (USA), however, XCOR Aerospace changed its plans, and finally, in 2017 it went bankrupt.

Future of Manned Suborbital Spaceflight:

Private companies such as Virgin Galactic, XCOR, Armadillo Aerospace, Airbus, Blue Origin, and Masten Space Systems continue to take an interest in suborbital spaceflight. NASA and others continue to experiment with scramjet-based hypersonic aircraft and they might eventually be used with flight profiles for suborbital spaceflight. Some non-profit groups like ARCA SPACE (New Mexico) and Copenhagen Suborbital (Denmark) are also attempting rocket-based launches.

Air Flight Mechanic

Preflight: This portion of the flight occurs on the ground where flight checks, push-back from the gate, and taxis to the runway occur. You take your seat, stow your hand luggage, and do up your seat belt.

Takeoff: The aircraft is powered up and accelerates down the runway.

Departure: The plane becomes airborne and ascends to a cruising altitude. Cruise: The aircraft travels through one or more airspace centers (i.e. zones) and nears the destination airport. Aircraft spend most of the duration of a flight doing this.

At this point in the flight profile, we'll derive equations for a normal cruise flight with a zero angle of attack (i.e. the aircraft is flying in the same direction as the movement of the air) and steady-state (i.e. at a constant speed). It is very easy, but do you have any idea about how to start? Yes, of course - Newton's Third Law of Motion is the key, and it's very simple. [41]

EF=MxA

When you are reminded of laws of motion, do not take another step before you draw a free body diagram, i.e. a diagram that shows the relative magnitude and direction of all the forces acting upon the object in the given situation. 

Once you've done the free body diagram, you're almost there!

• ΣFx=M*A

• ΣFy=M*A  

• The forces are divided into two vectors X and Y, so

• Thrust-Drag M*A=0 (i.e. there's no acceleration)

• Lift-Weight=M*A=0 (i.e. there's no acceleration)

• So, the lift is equal to weight and drag is equal to thrust.

If you're motivated to do so, you can start deriving equations for the climbing approach and any other situation. However, that's beyond the scope of this book Descent: The aircraft descends and is maneuvered to the destination airport.

• Approach: The aircraft is aligned with the designated landing runway.

• Landing: The aircraft lands on the designated runway breaks, slows down, taxis, to the destination gate, and parks - and then the flight is safely finished! Something is missing from all isn't them! We're saying the aircraft flies from an airport, takes off, cruises and goes to another airport, descends, approaches, and lands, but do you know how the aircraft really controls itself where there's no asphalt surface for it to dive on? It's time now to delve into aircraft controllability.

Aircraft Control

We'll start with aircraft. Let's suppose you're flying across the United States, perhaps from Los Angeles to San Diego. Your flight is halfway there and cruising at Flight level 330, which is at about 10 km altitude (33,000 ft). Now imagine that your airplane encounters a technical problem and all engines suddenly stop working. Though we are hypothesizing, this could actually occur if the fuel ran out, or if we flew through a cloud of volcanic ash. In 1998 British Airways Flight 9, a Boeing 747, for example, flew through a cloud of volcanic ash above Indonesia which resulted in the failure of all four engines. In this situation, there is no other option but to start a gliding flight.

How far do you think gliding aircraft can glide? A typical commercial aircraft can glide more than 170 km from a 10 km altitude! Thus in this specific scenario, the pilot could actually choose to glide either to LA or to SD safely. Now that is impressive, isn't it! Don't worry if your guess was incorrect. A solid understanding of flight mechanics can allow you to make this kind of calculation using some basic knowledge about the aircraft.

Depending on the type of aircraft flown there are different ways for controlling its direction, altitude, and the general controllability of its flight. You might be surprised to know that although electronic control devices are advanced today, mechanical cables and rods are used to transmit the forces from the cockpit to the aircraft's control surfaces.*

Cockpit

The pilot controls the aircraft from the cockpit (flight deck), which is usually near the front of an aircraft and is enclosed these days, except on some small aircraft. As you see, the cockpit is the place where the instrument panel contains the flight instruments. The controls that enable the pilot to fly the aircraft are there too. The cockpit is a wonderful and exciting place to visit!

You may ask the flight crew if you can visit it at a suitable time, and afterward, you will understand that a simple flight has to be very organized and that it's not always an easy job. At first sight, you'll notice that there are more than a hundred control systems for managing a flight.

Roll

Aircraft Control Surfaces Since aircraft function in a three-dimensional world, it is necessary to control their attitude (orientation) in flight. For the purpose of analysis, a flying aircraft is thought of as a particle. freedom (i.e. it can move independently in six possible ways in three-dimensional space). It can move along three perpendicular axes (i.e. forward/backward, up/down, left/right) and also rotate about those same perpendicular axes (i.e. pitch, yaw, and roll).

An aircraft's center of gravity is the point where its average mass is located. It's useful to define a three-dimensional coordinate system through this point with each axis perpendicular to the other two. Using that we can then define the aircraft's attitude by the amount of rotation along these principal axes. Rotation about the lateral axis is called pitch, rotation about the longitudinal axis is called the roll, and rotation about the vertical axis is yaw. Have you looked at an aircraft's moving surfaces carefully? Do you know what they're called and what they do? 

Earlier, you learned how an airfoil creates forces. Smaller airfoils such as elevators, rudders, ailerons as well as flaps are the control surfaces used to control aircraft. These are the basic means for making one fly smoothly and go wherever we want - there are other control surfaces, but these four are enough for the basics

Ailerons primarily control roll. The left aileron goes up and the right aileron goes down, if the pilot moves the control stick to the left, or turns the wheel counterclockwise. Lift on a wing is reduced, if its aileron is raised, and increased if its aileron is lowered. As a result, moving the control stick to the left causes the left wing to drop and the right-wing to rise.

The elevators primarily control pitch. These are the moveable parts at the back of the horizontal stabilizer on the aircraft's tail, and they move up and down together. The elevators go up if the pilot pulls the control stick backward, and

down if the control stick is pushed forward.

Poder

As you see, pulling the control wheel pushes the elevators which means the tail goes down and causes the nose to pitch up. The aircraft's wings will then fly at a higher angle of attack, which in turn, generates more lift - and also more drag

The rudder primarily controls yaw. It is part of the aircraft's tail assembly and is usually mounted on the trailing edge of the vertical stabilizer. The rudder turns to the left, if the pilot pushes the left pedal, and to the right if the right pedal is pushed. A right-turning rudder pushes the tail left and causes the nose to yaw to the right. If the rudder pedals are centered, the rudder returns to neutral and stops the yaw.

After the aileron, elevator, and rudder, the flap is the next important surface that helps to control an aircraft. You can see a fully deployed flap. It raises the Maximus If the flaps are deployed they deflect down, thereby increasing the effective curvature of the wing. They are generally used during low speed, high angle of attack flight especially at take-off and descent for landing Although high lift flaps are not used as ailerons at all on commercial aircraft. Sometimes they function primarily as ailerons. On some aircraft. aliens will "droop" when the flaps are deployed, thus acting as both a flap and a roll-control onboard aileron

These four are the primary surfaces for controlling an aircraft, but others help the flight go as expected too: spoilers, air brakes, slats, and trim tail. In a helicopter, it's a completely different ball game, which we learn neat

Helicopter Control

Unlike an airplane that forces air over a pair of fixed wings to fly, a helicopter does so by spinning a rotor blade at high speed. They are highly maneuverable aircraft, whose invention is attributed to Leonardo da Vinci (1452-1519) Russian-born Igor Sikorsky (1889-1972) developed the first practical design in the 1930s.

Typically, helicopters are used these days for military transportation and air-sea rescue. They fly upward against the force of gravity by using their motors to throw air down beneath them. Each blade in a helicopter's rotor is an airfoil, just as the wings of an airplane are.

The lift produced by the rotor aims straight upward for Collective pitch, but with a device called the Cyclic pitch control, the pilot can tilt the rotor blades to make the helicopter fly in a particular direction-using Cyclic pitch. Although most of the lift force still points upward, some of it now points to the front, back, left or right, tilting the entire helicopter and pushing it in that direction. Two disks, the upper and lower swash plates, transmit the intentions of the pilot in the cockpit to the rotor blades

The lower swashplate does not rotate but can tilt or move up and down. The upper swashplate spins with the rotors on ball bearings on top of the lower wash plate. When the pilot pushes the controls, the lower swashplate nudges the upper swashplate, and the blades are tilted in turn by a system of control mods. Everyone knows that a helicopter's rotors rotate, but did you know that they can also swivel back and forth as they rotate? That demands some

impressively intricate machinery!

You can see what is going on by using your arms and your body. For the rotation, stand up with your arms stretched out horizontally, and rotate your whole body slowly on the spot. For the swiveling, swivel your arms at the shoulders while you continue rotating. You're now mimicking what a helicopter does with its blades - except that its blades swivel 3 to 4 times every second while they are rotating! The main parts that achieve all of this are numbered in 

1. The blades are shaped like airfoils so they generate lift as they spin. 

2. Each blade can swivel as it spins.

3. Each blade can swivel as it spins. Vertical rods push the blades up and down, making them swivel as they rotate. 

4. A central axle connected to the engine makes the entire blade assembly rotate.

5. The cap above the rotors is missile proof to protect against enemy attacks.

6. Two turbo-shaft jet engines sit on either side of the rotors. If one engine fails, there should still be enough power from the other one to

According to the Laws of motion, any force (or action) produces an equal force (or reaction) in the opposite direction. This means the torque (rotating force) produced by a rotor's blades tends to turn the fuselage (main body) in the opposite direction. All helicopters have either a second propeller or another device to counteract the torque from the main blade. In most helicopters, a tail rotor balances the torque by pushing in the opposite direction to the main rotor. Some helicopters have two rotors mounted on the same shaft, which counter-rotate to cancel the torque.

Miscellaneous ways of Transportation

Jetman is called an Aerospace Transportation Vision in social media: Yves Rossy had the idea and then built a wing-suit system comprising a backpack equipped with semi-rigid airplane-type carbon-fiber wings that spanned roughly 2.4 meters (7.9 ft).

It was powered by four Jet-Cat P200 jet engines which he'd made from large model aircraft engines fueled by kerosene. He was then referred to in the press by various monikers, such as The Airman, Jetman, Rocketman, and Fusionman. In 2008, Rossy made a flight over the European Alps, reaching a top descent speed of 304 kph (189 mph), and an average speed of 200 kph (120 mph).

In November 2009, Rossy attempted flying across the Straits of Gibraltar, hoping to be the first person to fly between two continents using a jetpack. At about 1,950 m (6,500 ft) above Tangier in Morocco, he launched himself from a small plane and headed towards Atlanterra, Spain. The flight should have taken about a quarter of an hour, but because of strong winds and banks of clouds, he ditched into the sea. He was picked up ten minutes later by his support helicopter - just 5 km from the Spanish coast, flown to a hospital in Jerez, and soon released unhurt. The Spanish Coast Guard retrieved the jet pack, which had its own parachute and afloat.

Flight mechanics is the most applied part of aerospace engineering. Aircraft performance provides the lead for having satellites an operational reality in orbit, aircraft as transport vehicles, Jetman flying over the top of Mount Fuji - all of this occurs within the field of aerospace science! So now we'll review the fundamentals before you learn more of this miracle worker that makes things work in the aerospace industry.

Conclusion

In this chapter, we've explored the basic physical laws that govern flight in atmospheric flight and air travel and how the two are different, what their similarity and how the flight mechanic rules play a critical role in both of these. In the next chapter, we will learn about the systems and methods for communicating with spacecraft.

SIXTH CHAPTER: COMMUNICATION WITH SPACECRAFT

Humankind is exploring the universe using all available means: powerful telescopes on Earth and in space to study stars, astronauts to the Moon, an International Space Station orbiting Earth, even machines to other planets like Mars or Saturn! This is great, but how do we talk with them when they are so distant from us? If we can't talk to them, it won't matter what interesting things they might be doing because we won't know anything about them! So at the end of the day, it does not matter if we send a person or a machine to do the job. If we cannot communicate with them, no science will be done, as we'd have no interesting information about what they are seeing and measuring!

A lot of engineering is necessary to develop solutions to help us to communicate with our spacecraft. In this chapter, we will talk about how we use electromagnetic waves to communicate with our machines and our astronauts. We use electromagnetic waves to send information. Because space is "full" of vacuum no sound can be sent back to Earth. Because electromagnetic waves travel very quickly, we can learn what is happening in places very distant from Earth in the quickest way possible.

Data Transfer Using Electromagnetic Waves

Electromagnetic waves are very strange. Both visible light (the colors you see with your eyes) and X-rays (used for making radiographies) are electromagnetic waves. But it gets even stranger. It turns out that mobile phones, television, and many other devices communicate using electromagnetic waves. We use the same type of waves to both see and communicate! And how do electronic devices communicate using electromagnetic waves? How can we get information into them? By something called modulation.

Modulation of Electromagnetic Waves can be sensed by the receiver, so the information that was modulated into the waves can be extracted. For instance, NASA's Cassini mission, which was recently orbiting Saturn, needed to modify electromagnetic waves to send us information about what it saw there on Saturn. Can you imagine if we'd had no means to talk to Cassini? We would not have been able to learn as much as we know now about Saturn

Cassini modified electromagnetic waves by using its transfer-which is just a fancy name for the device we use to transmit and receive data by modulating and demodulating electromagnetic waves (From now on we will refer to this electromagnetic wave as the carrier as they carry the information) After that Consent these electromagnetic waves using its antenna very quickly back to Earth. There is a place we call the ground station, big antennas received a tiny signal and the information Cassini modulated into its carrier was extracted. To talk to Cassini we used the same big antenna and powerful amplifiers. An amplifier is a device that creates a powerful signal out of a weaker one And this is basically how we talk to spacecraft!

You might be wondering why we said we receive a tiny signal here on Earth Fait question! Well, it turns out that once it leaves the spacecraft anteria the electromagnetic wave distributes its power throughout space in an ever-expanding spherical shape The further the wave goes, the bigger that sphere becomes and the bigger the area the signal is distributed over.

Spacecraft

Our spacecraft is very distant from Earth so the sphere is very big and the signal gets too tiny. When the wave loses its power we say that the signals are attenuated

As a result, all our spacecraft need to be able to modify electromagnetic waves so they can send information to Earth and extract data from the signals coming from Earth. This is why all these machines are equipped with receivers (for taking the incoming signal and extracting information from it) and transmitters (for taking what they want to say and putting it into an electromagnetic wave). into an

They also need amplifiers and antennas. If you look at a picture of a satellite you will always see some kind of antenna so it can talk with us on Earth. The top of Cassini in Figure 6.4 has a white plate, for instance. That is its main antenna.

When it comes to talking to distant machines we should use parabolic antennas because they concentrate all the radiated energy into a small point in the sky. It is not very different from those antennas you can see on any house roof for watching satellite TV.

Ground Stations

You might be wondering what we use back on Earth to receive spacecraft signals. Special places called ground stations are in charge of receiving and dealing with our spatial data. As our machines are so distant from Earth, transmitted signals are so faint that it is very difficult to properly receive information. It is not only a matter of signal power, but time too: we are used to receiving instantaneous replies while using modern electronics gadgets, but when it comes to deep space spacecraft, it takes some time (sometimes even a day) to receive a reply.

To communicate with our electronic explorers, it is necessary to apply a wide variety of complicated telecommunications techniques. It is interesting to note that many of these deep space techniques are applied to modem everyday systems. The best example of this is with current mobile phones: LTE (4G) technology uses physical principles derived from arraying techniques, which have been studied in the aerospace sector to overcome the fact that big receiving power is necessary for receiving weak signals from spacecraft. We will talk more about this later.

If you have ever come across a ground station, you will have seen big dish antennas pointing to the sky. The farther the spacecraft is, the bigger the antennas need to be. For instance, both NASA and ESA (European Space Agency) use ground stations networks to communicate with all these machines that are so distant from Earth. They use thirty-four and seventy-meter diameter antennas (the heights of 12 and 23-story buildings!) to receive and transmit information.

These ground stations are placed around 120 longitudes from each other to operate 24/7 without losing a single bit of data. If you take a look at the globe of the Earth in.

Depending on what type of spacecraft we want to track we place our ground stations at different locations. For instance, if we want to track satellites orbiting Earth with polar orbits, which is widely used for weather and defense satellites, we will place them as close as we can to the Earth Poles. This will ensure the maximum possible number of satellites pass over the ground station. This is why you can find them in places like Svalbard, Norway.

Here is a ground station in Svalbard. The white bubbles are called radomes. They cover ground station antennas and protect them from bad weather (like snow, wind, etc.). Nevertheless, we need more than huge antennas and many ground stations, if we want to communicate with other planets. Math is mandatory for doing this job! We will discuss further some nice tricks we can use so we can hear our spacecraft. At the end of the day, talking to a distant spacecraft is pretty much like talking to some friends in a noisy place. You have to use your imagination to find out ways to be able to talk to them properly.

One thing we usually do is cup our hands behind our ears to hear better. By doing this, we are somehow amplifying the incoming signal. Well, Figure 6.7 Polar Orbit [own work] this is the main point of having huge antennas - they're like having huge ears for listening to the sky. It is important to note that sound and electromagnetic waves are not the same things at all, but big ears are a nice way of visualizing the purpose of these antennas though.

Sound waves are mechanical waves, so they need a medium for propagating through space. The same thing does not apply to electromagnetic waves, so they can be used for telecommunication in space. By looking into how these waves behave we can even learn things about other planets, as you will see later on in this chapter. Let's go back to our example of talking to some friends in a crowded place. You could try to shout to be heard - which is why very powerful amplifiers are used at this kind of ground station. NASA also has spacecraft outside the Solar System, like Voyagers I and II, which left the Earth in the 70s containing a gold disc of information about us, designed by Carl Sagan.

Now things start to get tricky! Another way to help your friends to communicate is to use a made-up code, for instance repeating each phrase twice. That will increase the probability of being heard. If your friends do not hear you the first time you say something, they might the second time. They could even get one part of the sentence in the first try and the other part in the second! By doing this, you are adding what is called redundancy to the message

Mostyn telecommunication systems use redundancy to enhance communication Special codes called Forward Error Correction Codes are designed to add redundancy in a controlled manner to messages. It does increase the amount of information that we send through our channel (i.e. doubles it, if we are sending the message twice as in this simplified model) but on the other hand, it will increase the probability of successful communication. Success is measured by engineers using a test called a BER (Bit Error Rate), which allows us to measure the probability of receiving a bit of digital information wrongly. By applying Forward Error Correction Codes we will get a better BER ratio.

Antennas

There are many types of antennas. If we want to know how one particular antenna radiates, we need to look at its radiation pattern. Radiation pattern calculation is quite complicated, but we will look at some radiation pattern types. Depending on the application we could need to radiate to a single point or to all points in the sky. For example, if we want to use an antenna in a wifi repeater, we will need one that radiates to all points around it. There are two ways of increasing the signal gain of the antenna being used. We can use one big antenna and/or synthesize the signals from an array (Le group) of separated antennas.

Big Cassegrain Antennas electromagnetic waves into a single point. Its biggest part is the main reflector, which captures electromagnetic waves, so the bigger this part is, the greater the gain will be. We define gain as the ability to amplify incoming signals. After bouncing off the main reflector surface, signals go to the sub-reflector, which is the metallic structure above the antenna, fixed there by the four metallic legs. Signals are then sent to the center of the main reflector, where they are typically captured and passed to electronic systems.

Since radiation pattern calculation is complicated, we can't go into much detail about it here, but we can at least use a valid approximation to talk about the relationship between how big a dish is and the gain that an antenna has:

Gα (n'd/ X)²

where d is our antenna diameter, it is the irrational number pi and A is our signal wavelength. From the equation, we see that the bigger the antenna is, (d is in the numerator) and the higher the frequency is, (higher frequencies have a smaller wavelength) the more the gain will be.

Therefore, according to this equation, we know that we want big antennas and higher frequencies. An antenna that is 70 m in diameter can amplify a maximum of 551×105 times the incoming signal. (Please note that there are technical issues that make operating big antennas and high frequencies complicated - but we are not dealing with them here.)

An antenna that is 34 m in diameter can amplify a maximum of 129×10* times the incoming signal at a frequency of 32 GHz. As this equation does not take into account many issues that occur for real antennas, these are maximum values that will not be met in reality.

Wave Features

When it comes to signals, everything has to do with waves. Because of this, concepts like frequency, amplitude, and especially phase need to be well understood to really master what is going on in a parabolic antenna.

To properly address this matter, we will make a one-page quick review of waves. We will start with a classical wave-as shown in Figure 6.10-and will now talk about wave features.

Amplitude: This is the maximum value the wave reaches on the vertical, i.e. y-axis. In our example, at point 0.0, A-1. Amplitude is related to wave power, so the higher the amplitude, the more powerful the wave is. It turns out we can modify wave characteristics, such as wave amplitude to send information. This is called Amplitude Modulation (AM) and it is the simplest way to modulate the wave. The distance (when it comes to space, not time) between two amplitude maximum values is called wavelength and is denoted by the Greek letter lambda, A.

The wave amplitude is formed by the former amplitude of the faster blue wave times our information (which this time, as a matter of fact, is another wave, the red wave). Therefore, to use AM, we just have to multiply the information and the wave. The blue wave is the carrier and the other red wave, that modifies the carrier amplitude as time goes on is the envelope. But amplitude is not the only feature we can modify to transmit information using electromagnetic waves. This is the oscillation state at any given point, both space (r") and time (73 The same values will occur many times in space and time, as simple waves are periodic. A and I will tell us how long it will take for a value to be repeated both in time () and space (A). Phase is very important when it comes to combining signals. Let me show you why. By observing the wave we will see what happens if we change its initial phase from 0 tons. The green wave can be seen to be moving the blue wave a little bit to the right or to the left in the graph.

If we tried to combine them by adding them together, we'd obtain a value for all given times and would be a so-called destructive combination. We could measure a phase difference at any particular point by comparing the wave oscillating state at that point to a given reference. You can see both waves are not equal. They have the same frequency and amplitude but a different phase.

If the phase was the same, then adding them together would give us a wave with a greater amplitude, which would be a powerful wave, i.e. a powerful signal. This is called constructive combination. We need to pay great attention to phase, as it is important for combining signals - as you will see in the section below called Arraying Antenna.

Modifying the wave phase is also a good method for modulating a carrier and sending information. In fact, this is widely used in the aerospace industry and is called Phase Modulation (PM). In the first graph in Figure 6.13 below you can see a binary signal (1 and 0 values) represented by a red line. We superimposed this value over a normal cosine wave and then merged them. You can see the result in the lower graph. Note that every time the red line rises or lowers. (representing a '1' or a '0' respectively), the phase of the carrier changes in the result. 

Phase Modulation (own work Frequency: This is also a very important characteristic of a wave. It lets us know how many cycles per second a wave is performing. It is measured in Hertz (Hz) Fig 14 Waves with two frequencies. We can also modify carrier frequency to encode information into a magnetic wave This is called Frequency Modulation (FM). There is an

evenly proportional relationship between frequency and wavelength All the wave features can be modified to transmit information. The techniques for this are called modulation techniques.

Other Things We Learn from Wave Features states that we can learn other things based on these three wave characteristics (amplitude, phase, and frequency) too. An electromagnetic wave undergoes some modifications of its characteristics depending on the medium it is going through and the interfaces between those mediums.

Because of that, we can even learn about another planet's atmosphere by sending a signal from our spacecraft to Earth if the signal travels through its atmosphere This is called the Radio Occultation Technique. To do that it is necessary to first extract the Earth's atmospheric influence out of the signal so we can distinguish between modifications introduced by its atmosphere and those that come from far beyond Earth's protective atmosphere.

Parabolic Antenna Shape

Now that we have a deeper knowledge about waves we will return to our big Cassegrain antenna and analyze its shape called a parabolic antenna because of the shape of the main reflector. It is designed with this particular shape to ensure a constructive combination can occur at a particular point on the antenna. Let's take a closer look at the antenna shape to truly understand what is going on in the Plane.

Mathematically Q P: F, and Q PF and Q PF are the same lengths and that applies regardless of which P point you decide to use as long as P is on the parabolic-shaped surface. This is important because this means all the paths our signal could travel along from the plane of Q to point F, that pass through the parabolic surface, are the same length. So, if the waves are at the same oscillation state at plane Q then their phase will be the same at point F too. Therefore we can collect many waves present at plane Q and concentrate them at point F

As the oscillation state will be the same for all of them at F, then a constructive combination will take place and, as we've seen already, this means we will obtain a powerful signal. The higher the number of waves that are combined at 1, the stranger the signal will be. If our antenna is big more waves present at plane Q will be steered to F and properly combined. We, therefore, end up with our own conclusion: the bigger the antenna is the greater its amplifying factor

Arraying Antenna

As we've seen previously, it's advantageous to concentrate signals and combine them with the same phase. And the bigger the area we use to collect these signals e the bigger the antenna) the bigger the amplifying factor combines them in phase. Then, why would we use just one antenna?

If we use more collecting surfaces and then combine the collected signals with the same phase we will mathematically, create a bigger antenna. It is possible to use two big and separated antennas to record a signal coming from a far point and then combine them with the proper phase. To do it we'd have to generate the same effect a parabolic surface creates in waves that bounce on its main reflector

We would also have to introduce a particular extra delay, as combining signals from two distant antennas involves another issue. It turns out when it comes to signals from a point far distant from Earth and antennas are distant from each other that the wavefront will not reach both antennas at the same time.

Gmund Station & Figure 16 Geometric delay between two ground stations receiving the same spacecraft signal town work

This is an issue. Because there is a delay in the system between Ground Stations A and B. If we try to combine the signals recorded at both antennas for a given time, without taking the delay into account, we will not obtain a constructive combination. We will not be sensing the same oscillation state and therefore not obtain the desired constructive combination. We would have to record signals during a period and then try to introduce a delay into one set of them, to minimize the relative phase between both of them. By doing this we will maximize wave amplitude in the resulting combination.

What we are doing is to correct the geometrical delay the signal is undergoing. To properly do this, the influence of the atmosphere above both antennas has to be taken into account too. An interesting consequence of this fact is that to obtain the proper geometrical delay-in order to know the path difference between these two antennas as seen by the wave-it is necessary to know the horizontal distance between both antennas¹2.

This horizontal distance has to be accurate in terms of wavelengths, which uses distances beneath the centimeter scale. This combination also allows us to learn. about the movements of the Earth's Tectonic Plates: by trial-and-error, we can introduce different delays to the signal until we obtain a maximum value in the combination. That way we will know the distance between antennas. If we monitor the evolution of these distances over time, we will be measuring the movement between ground stations (i.e. between two sites on the Earth's surface). This physical principle is widely used in geodetics (the science of measuring the earth).

Three Data Types in Spacecraft Telecommunication

A ground station performs three main tasks when it comes to spacecraft on missions: Tracking, Telemetry, and Command - known as TTC.

1. Tracking

The ground station follows a spacecraft as it goes through the sky above our heads, and meanwhile receives some interesting data about the spacecraft's movement and position. This data is very important and will be used to decide orbital maneuvers.

It is necessary to avoid any possible crash with planets, moons, or other 11 Phase differences between both waves. This is a trigonometric issue related to the signal source point in the sky and the horizontal distance between both antennas.

Spacecraft while keeping our spacecraft where it is supposed to be in fact, if you are used to watching satellite TV, that is only possible because a group of people works very hard to make sure the satellite is where it is supposed to be, so you can point your antenna to a well-known point in the sky and watch your favorite TV shows. This applies even to geostationary satellites which are supposed to be always at a fixed point in the sky. Orbital station-keeping maneuvers are necessary to ensure satellites remain where they are supposed to be.

Doppler is a physical principle widely used in modern devices. For instance, it is used with radars to learn the radial speed (.e. how quickly the target is getting closer to us or further away from us). Radial speed slightly modifies the way we perceive the received frequency coming from the spacecraft. If the spacecraft is moving closer to us, we will perceive a slightly higher frequency, and if it is. moving away from us, we will perceive a slightly lower frequency.

Have you ever wondered how astronomers know the Universe is expanding? Here is the answer: the Doppler effect! Radiation coming from stars moving away from us has a slightly lower frequency than it should have. When it comes to visible light from those stars, we see non-red colored stars in red (or with an unusually higher red content), as those frequencies are lower than they should be. This is called the redshift. Blueshift happens when an object is moving closer to us.

Sequential Ranging: So far so good. We know how fast our spacecraft is moving in the radial direction. But how far away is it? This is a very interesting question and we have another tool, called ranging that will help us to know. Now, imagine you are in a dark cavern. You don't know where the walls are and you are not able to see them. What could you do to know how far you are from the wall?

If you had a baseball ball then you could throw it at the wall (let's assume you know what direction you should throw it). Your ball hits the wall quickly and then comes back to you. If you had a good clock to measure how long it took for the ball to get back to you and you know the ball speed (that's the tricky part, then you'd be able to work out the distance between the wall and yourself. Depending on how accurately you can measure time with your watch you will be able to measure the distance to the wall very precisely. Let t be the time it takes the ball to get to the wall and back. Let the ball speed (let's also assume it is constant the whole time, even when it is bounced on the wall). Then we know that din (txt). If you want to know how far you are from that dark cavern wall, you have to take into account that b is two times the distance to the wall, as your ball traveled to the wall and back again. So if de is the distance to the wall, then:

da = di/2

For spacecraft we know how fast light travels in a vacuum: it is well-known physic constant, Ca. Now let's get back to satellites. A special signal, called a ranging signal, is sent with data. Spacecraft need some time (a very small amor signal and send it back to Earth. t of time) to get that, so we measure how long it takes for the signal to get to the spacecraft and back and how long the spacecraft needs for processing this signal and sending it back to Earth. As it was for you standing in the middle of a dark cavern, measuring time accurately is very important.

Because of this, a special type of clock called an atomic clock is needed. It allows us to accurately know when we send our ball (the ranging signal) to our spacecraft and when we receive it. What we will measure are, in fact, phase differences. (If you're not sure what a phase in a carrier signal is, see the Wave Features section in this chapter.) To avoid inaccuracies resulting from the fact that you don't know how many entire cycles your signal has undergone before getting back to you, different frequencies are used. The larger the number of frequencies, the smaller the inaccuracy.

Delta DOR: We are almost there now! We know how fast our spacecraft is moving, and how far it is. But where in the celestial sphere is it? Should we point antennas to the South... East...? Well, you will have had a basic idea from the very beginning, because if, for instance, you are tracking something orbiting Mars your spacecraft will be positioned where Mars is positioned in the Sky. That is fine, but if you want something more accurate than that, if you are receiving your maximum signal", you can be sure very accurately whereabouts on the day your spacecraft is (depending on your antenna radiation pattern). However, we will need something even more accurate than that to land safely on the Martian surface! How can we decrease that error? roding something called Delta DOR which is based on arraying, We will perform measurements using two ground stations at the same time, and then, by properly combining the signals, we will know very precisely from what point in the sky the signals are coming,

2. Telemetry

All spacecraft instrument data and spacecraft status is sent back to Earth and binary data. Raw data that comes out of spacecraft devices (cameras, radars...) is sent to Earth and is known as telemetry data. After processing this data, the science we read in newspapers is generated.

3. Command

Every time we want to order the spacecraft to do something, we will transmit information to it. Every time we want to tell the spacecraft to do something, to turn on a thruster, activate some instrument, or maybe perform a satire update, we will do it by sending data to it. This is widely known as a command.

Conclusion

In this chapter, you learned about the methods that we use to communicate with spacecraft, as well as some of the physics that underlies those techniques. In the next chapter, we will be shifting our focus to ways that you can get more involved in the aerospace industry and boost your career.

SEVENTH CHAPTER: CAREER OVERVIEW IN THE AEROSPACE INDUSTRY

Jens Strahmann, Former Head of the Airbus High Lift Department and current Vice President of PACAVI Aircraft Conversion, advises what a career in aerospace engineering would look like, what experience in this industry would bring, and how being open-minded helps us move along with the tremendous technology of the aerospace engineering world. It's Like to Be a Scientist/Engineer in Aerospace. What is Industry? We'll look at this question from several different angles.

1. Experience - what does it mean?

2. Projects come and go Synergies: using new

3. an airworthy environment 

4. Being open-minded and critical techniques in

5. What is doable- and what will remain as an idea only?

6. Not invented here 

7. Young professionals and old managers

8. Small, medium, large companies 

9. Team and individual 

10. Timing for new ideas

11. Innovation cycle: aeronautics, astronautics, and automotive

12. How do I start?

1. Experience

Experience means learning from bad and good - failure or success. The experience of failure you will never forget and is character-forming. Experience from success grows your motivation and provides a positive attitude. Feedback is the tool for improvement! Even negative feedback can be good feedback.

The right level of experience is key:

• too much will reduce your decision-making risk

• too little will result in trivial mistakes

Suggestion: A senior mentor who helps eliminate trivial mistakes but encourages decision-making ability is important for a young professional's career.

2. Projects Come and Go

New projects are the fluid for energizing your mind-motor. Every scientist is interested in challenging new projects, but be aware that you are dealing with projects of the right size In aeronautics or astronautics the maturation cycle can be especially long.

Young scientists have started their careers in huge projects in big companies and the project has come to fruition 25 years later or worse, the project was canceled after 10 to 15 years and ended in the big banana. Even if they'd gathered a vast amount of experience, in the end, it was for nothing and could drag them into a big hole mentally.

Starting in projects with time schedules of some months might be better. Starting in small/medium-sized innovative organizations provides you with fast and direct feedback which is essential for your future personal development. Really new and innovative ideas are coming from small/medium enterprises anyway.

3. Synergies: Using New Techniques in an Airworthy Environment

By starting in small companies, you will acquire a lot of innovative, sometimes disruptive knowledge that is key for your future career. This knowledge could be essential for your next profession.

Even if, at a first glance, the acquired skills have nothing to do with the new project, very often they do. It might be the tools used, the processes, the network of people and companies, or the mindset. In fact, using disruptive knowledge from an earlier project paired with a new subject could raise synergies nobody has envisioned.

Flight control for nearly 100 years was dominated by analog techniques, but by adding the up-and-coming digital processors, reliable data-storage, and specific program languages it has now become possible to control aircraft using fly-by-wire (i.e. totally electronic) techniques.

This used to be a disruptive brand-new approach. Today nobody would even argue about the feasibility of digital aircraft control and soon Passenger aircraft will be flown unmanned using a combination of next-generation network technologies, fly-by-wire, GPS, and satellite communications.

4. Being Open-minded and Critical

Being a team player does not mean you do not challenge obviously wrong decisions! The secret is how you challenge them. It is very important to discuss the issue in a very respectful way, even if you are young and you are 100% sure to be right (what else) Being open-minded, asking, and trying to understand are factors in being an exciting person. You are leading by asking and showing social competence if you retain the talent for being open-minded and cooperative.

5. What is doable - and What Will Remain an Idea Only?

Pretty often great ideas get stuck in the company's gearbox. The traction is somehow too weak. The decision process takes forever! Momentum is soon gone. Innovations brought to the market like iPod, iPad, iPhone have been great successes, but the company that won the race was not the one that had dominated the market for several years.

Compare Nokia and Apple. Both companies had different starting points for approaching their smartphone. Apple had a convincing, innovative but risky approach. Nokia chose the safe-way (never touch a running system) and lost completely, even though the prerequisites were clearly on their side. The consequences for Nokia were dramatic: the wrong path led them to insignificance.

The innovation cycle for smartphones is very, very short and once you lose track, even money cannot rescue your company. This was t "unpleasant" for the upper management, but dramatic for all their employees. Senior Technical Engineers at Nokia knew that for sure, but they could not convince their managers to accept their arguments.

Even though in the past technical director's guided companies, today it's financers, lawyers, and economists who are in the driver seats. If only money, no risk, "let's take the safe-way", and a lack of real research are the guiding principles. Only start-ups with disruptive ideas can be the real innovators. The results of this phenomenon can be seen today. The only chance the big companies have is to buy the start-ups and consume their products.

This is happening even in the aerospace industry. The modern lightweight battery, technology inspired by the satellite industry, was developed by computer, cellphone, or small car manufacturers. Modern innovative LED lighting came from consumer electric appliances, not from aircraft cabin lighting companies or even Original Equipment Manufacturers (OEMs) 3D printed parts are used all over in industry, and finally (half-heartedly) the aircraft Industry is adopting the technique - but is hiding its more innovative usage behind Airworthiness Regulations.

6. Not Invented Here

Especially in large enterprises clustered in several locations and/or countries and even more especially if you are not working in that central location-it is very difficult to spread your inventions or ideas for solving a problem.

The journey could be very long and exhaustive. A solution might be a mentor, a sponsor, a network of open-minded colleagues, or better a gray eminence. None of these supporters come for free, so meetings, training, or coaching will help to form a group of supporting staff. This will help to overcome the phrase: "Not invented here in the center". Even if the management will never admit that the company works centralized, you can be 100% sure it is!

7. Young Professionals and Old Managers

What is the difference between a young professional and an old (experienced) senior manager? It is how they approach a task or a problem. In a long-lasting career, an experienced manager has developed a method for solution-finding. It is a method formed by failure, success, and the decision-making process and has cost the company a lot of money. Recently tools have been created to support systematic failure analysis, knowledge transfer, retention of knowledge. All these processes could help minimize the legacy process of trial and error.

The idea behind them is to shorten the experience cycle. Good intentions are sometimes poorly realized. Much better would be the pairing of a senior manager with young talent for a dedicated transition time and follow-up period. This would need strategic personnel planning and future market orientation, which might be difficult in an industry environment dominated by short-term and/or extremely short profit and loss cycles. After all, what kind of strategy can you form if you do not know if the company will still exist in the next three months!

Unfortunately, industries and OEM with medium/long innovation cycles do not behave differently - not even when it is really necessary.

8. Small, Medium, and Large Companies

There are different advantages and disadvantages to working in small, medium or large companies. 

For mainstream companies (medium or large organizations), the pros include:

• an uncluttered organization

• an established hierarchy

• existing processes

• existing tools educated staff

For a specific organization, the pros include: a dedicated group with special knowledge

• smaller/more effective units

• better change processes (i.e. better reactivity)

• more flexible units dedicated documentation

• more effective configuration-control

• independence from "elephant" processes

• prototype character visibility

There are pros and cons for both organizational types. A lesson learned in big organizations with complicated interfaces between development. production and flight testing have not proven to provide the most effective type of certification within the shortest time. A better organization therefore might be a dedicated clearly-arranged center including specific production and specific development with a dedicated responsible test center. This would anyone minimal s is minimal Interferences with production and would not edit the mainstream manufacturing process. This might be the leanest approach

9. Team and Individual

Employment will usually start in a team approach. Learning from others is smart-but doing things the same way as the others are not smart enough. It is important to find your own way of working and being a valuable add-on to the team effort. This is not limited to expertise or knowledge, personality and social competence are of equal importance. Inspiring the team with your specific personality is sometimes even more important.

For example, if your view on a problem is optimistic and solution-oriented rather than pessimistic, it makes your mind open to nonstandard solutions. As someone wisely said: The difference between an optimist and a pessimist is that a pessimist is an optimist with too much experience:

The real assets of successful enterprises are their personnel, but on the other hand, its biggest problems come from that person as well! That sounds paradoxical initially, but only an effective balance between both will be successful.

Real team spirit is the basis of an enterprise but does not forget that a team consists of individuals, who are different and want to make a career. Nearly all employment starts in a team in which persons take responsibilities and only real team-players will be successful.

10. Timing for New Ideas

Having a great idea does not automatically mean you are successful. The timing for realizing ideas has to be right too. Very often ideas are brilliant but they do not match the company's environment. What does that mean? In huge operation idea spaces, idea processes, idea brokers, idea integrators, and so on are formalized to canalize the ideas for evaluation purposes

Senior experts judge and filter new ideas and pick up or dismiss them.

Sometimes good or bad coincidences can judge your concept, which can be frustrating because those experts do not have the vision of the originator. The time required for presenting ideas is sometimes limited and some aspects do not get recognized as a result. What to do?

• Find a sponsor for your idea

• Use your network and enlarge it.

• Present your concept idea on a level so others can understand Don't be too technical-make it easy to understand and simple to repeat to others.

• Be engaged show confidence and show your eyes sparkling with joy.

If these suggestions do not work, you have only two options:

• drop the idea-OR if you are convinced about your idea 

• put it into a broader space outside of your direct sphere of influence. Find people and organizations with the same spirit and make it your own business.

One thing is not allowed: being frustrated/destructive and belonging to the other 60% of the employees who have already internally quit their job. That is not good for the economy, your company, and most importantly-not good for you!

11. Innovation Cycle: Aeronautics, Astronautics, and Automotive

An innovation cycle defines an idea or an invention that has been realized economically. In the 1950s, 60s, and up to the 80s, astronautics was the leading technology driver and innovations appeared everywhere: the moon landing, satellites, shuttle, space station Technologies stemmed from those huge programs and influenced navigation to communicate flight guidance and control, computer technologies, and digitalization

Digital flight control was one of the major innovations that inspirest aeronautics. The reproduction of systems, lightweight computers, digital navigation, reliable data storage, and digital communication made it possible to establish fly-by-wire in commercial transport aircraft. Today all new developments for commercial aircraft are fly-by-wire, instead of the old analog flight control. Astronautical and aeronautical technologies have advanced by decades compared with automotive technologies.

That has changed in the last few years. Electric driven and controlled cars being is only an intermediate step) will dominate the market shortly. The force of competing companies, scientists, engineers, and money involved is enormous and fuels shorter innovation cycles. Efforts to research energy storage, 3D printing, and autonomous driving are relevant for the future of any car manufacturer.

Even German car manufacturers are investing a lot of money in these developments, as they know full well that their current leading position in car manufacturing worldwide is in danger. The innovation cycle started by TESLA is heating up and has started a revolution rather than an evolution. The car will not only be a transport but communication and living center in the future.

If you miss the trend or innovation you could be soon out of the market no matter how big your company is. 

As a matter of fact, astronautics/aeronautics will use innovations and new developments stemming from automotive in the next decade, unless new horizons come from deep space exploration or manned missions to other planets.

12. How do I Start?

This is always a good question! Often the university or the company has been named the most important factor. That might still be the case, but only for exposed non-open positions. Today the most successful and shortest way is to take the initiative yourself! If you have the chance of talking to engineers/managers during a conference, fair, exhibition, or talk, use it to let others commit to you. Be engaged, a bit devoted. friendly, optimistic, and interested in everything. If contact is started that way, hang in there and commit to an internship, hands-on training master thesis, or other employment. Never ask for money or a vacation! Money will come and vacations will happen.

It would be helpful to know what you want. That sounds easy, but in most cases, it is not. For example, a young pilot in education had to wait for his job because of a waiting list. He could have waited forever, but after seeing a sign on the wall of a building saying Flight Test, he invited himself to the company and managed to talk to the senior Flight Test Engineer.

Explaining where he was coming from and that he wanted to work for the company no matter what - because he wanted to fly missions and everything close to that. After a few appointments, he managed to work for the company and had the experience of his lifetime - being heavily involved in development testing for an aircraft prototype. Only a few years later he was the Lead Technical Pilot for a big Airline.

If you know what you want and demonstrate engagement you will gain the commitment of someone, who will act as a mentor. Somebody promoting you is more effective than promoting yourself.

Make the difference - good luck!