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AE1110x - Introduction to Aeronautical Engineering

Exercise 1 What do we mean when we say that Aeronautical Engineering is multidisciplinary? A)  You need a lot of people to build an aircraft B)  Designing an aircraft requires knowledge on many domains C)  Various perspectives lead to different visions on how an aircraft should look like. D)   Aeronautical Engineering is a very difficult field of science.

Exercise 2 Below you see a picture of six different aircraft designs. Which picture belongs to which field of  expertise?

Figure 1: ’Ideal’ aircraft designs according to various disciplines.

Exercise 3 In this lecture the first powered, heavier-than-air, flight ever has been discussed: The Wright Brothers’ flight with the Flyer I. This exercise serves as an illustration of the progress made since. 1) Look up what the distance (in metres) flown by the Wright brothers in their first flight was. 2) Now to get a sense of the progress, look up what the distance covered (in kilometres) by the longest non-stop scheduled flight (as of November 2013) is.

Exercise 4 What is/are the distinct features of modern aircraft?  (Multiple answers can be correct) A)  The use of bigger engines B)  The use of new airfoils C)  The use of new materials D)  The use of longer fuselages E)  The distinct design for passenger/cargo transport

Exercises Lecture 1 - Introduction & Ballooning 

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AE1110x - Introduction to Aeronautical Engineering

Exercise 5 Which of the following are advantages of the thick wing profiles, used from the 1930s onwards (like in the Fokker V II shown below)?  (Multiple answers can be correct)

Figure 2: The Fokker F VII (Image courtesy of  Kitchener.lord , CC - BY - NC - ND) A)  Thick wings provide more lift B)  Thick wings are easier to make structurally stiff enough C)  Thick wings are easier to maintain D)  Thick wings make an aircraft more agile E)  Thick wings can hold more fuel

Exercise 6 Earlier on you’ve looked up yourself the staggering difference between the distance travelled by the Wright brothers and modern aircraft. Another example of the progress made is the travel time of  the Hindenburg of an Atlantic crossing. Look up the record time (in hours) set for a double Atlantic crossing by the Hindenburg.

Exercise 7 What is the main reason that airships experience a high drag when moving? A)  Airships are not very aerodynamically shaped B)  Airships are primarily designed to hang still in the air C)  Airships fly at low altitudes, where the air density is high D)   Airships have an enormous volume

Exercise 8 What is the modified equation of state which we will use in our lectures?

Exercise 9 A typical volume of a modern hot air balloon is 2500 cubic metres, and a typical maximum temperature of the hot air is 120 degrees Celsius. Given these figures, and an outside air temperature and density of 15 C and 1.225 kg/m3 respectively, compute the maximum mass (in kilograms) of  the balloon, basket and payload. ◦

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Exercises Lecture 1 - Introduction & Ballooning 

AE1110x - Introduction to Aeronautical Engineering

Exercise 10 Suppose that, on a day when the outside temperature is 15 degrees Celsius, we fill a balloon with pure nitrogen gas, of which the molar mass is 28 grams per mole. Now suppose that we want to heat up a second (equally large) balloon containing air, such that it generates the same amount of  lift. To what temperature (in degrees Celsius) should we heat up the second balloon?

Exercise 11 Some say that the hot air balloons with which the Montgolfier brothers performed their first flight had a volume of 1700 cubic metres and could lift 780 kilograms (that includes the balloon, basket and payload). Assume that the balloon took off on a day when the sea level pressure was 1013.25 hPa. Given an outside temperature of 10.0 degrees Celsius, compute the temperature of the air (in degrees Celsius) in the balloon.

Exercise 12 Others say that the Montgolfier brothers’ balloon was 23 metres high and 14 metres wide. Calculate the temperature of the air in the balloon (in degrees Celsius) for this situation as well.   (Assume  the balloon to be spherical, and then elongated by a factor 23/14 in height).

Exercise 13 During the lecture Mr. Hoekstra posed the question: "How many hot air party balloons could you safely carry before getting airborne?" This is exactly what we will find out now!   (Before making  this exercises, first make an educated guess!) Suppose that a party balloon is spherical, has a radius of 16 centimetres and is filled with helium. Furthermore suppose that we do our experiment under standard atmospheric conditions, when the air density is ρ = 1.225kg/m3 . How many of these balloons should a 75 kilogram human carry in order to become airborne?

Exercises Lecture 1 - Introduction & Ballooning 

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