Name the existing propulsion concepts for Aircrafts
Name the two main tasks of aircraft engines
Name the formula for thrust.
How can the thrust be increased?
What has to be taken into account when placing the control surface around the engine?
Name the formulas for
Jet performance
Effective power
Dissipation
State the internal efficiency formula
Name the for reasons why the internal eff. is always <1
Define the external efficiency.
What other name can be used for it?
Formula and equations for fuel consumption at standstill
Propeller engine equations
Thrust
Jet Power
Calculation of propeller thrust
Bernoulli equation
continuity equation
Final equation
Equations for standstill of propeller engine
thrust
jet stream velocity
continuity
Vr
mfuel
bF
Propeller efficiency
Inner efficiency
specific consumption
Difference in total efficiency between Jet and Propeller.
Name the predominant arrangement of piston engines (until ww2) and one special feature.
What advantage occurs from that special feature?
What disadvantages occur?
Name todays predominant arrangement of piston engines.
What Type of aircrafts still use them?
What is the reason for the engines to still be at the state of art of the 1960s ?
Name the specialty when it comes to ultra light aircrafts
History of jet engines
Name the first operational and certified Turbo-fans
Define the Bypass-ratio and name typical values (beginning and today)
Name two advantages and two disadvantages of turbo fans over turbo jets.
State 3 advantages of the RR Three-Spool concept
Which problems occur with increasing bypass ratio?
How are these problems solved in modern aircrafts?
What are the advantages of this concept?
What is the trend for next gen turbo-fans? (i.e. GE eCore)
What are the main fields of use for turbo-props?
Thrust distribution prop/jet?
2 Advantages
2 disadvantages
Name the current trend for turbo-props.
What is the main purpose for shifting from turbo-props to open rotors (udf)
Explain the structure of a UDF engine
Name 4 benefits from electric propulsion concepts
Name the (dis)advantages of electric propulsion concepts regarding
Energy density
storage
refueling
efficiencies
State the critical enabling value for on-demand air mobility missions regarding energy density
Explain the four stages of electrification
Power/Energy- Hybridization points A, B, C
Hydrogen
Efficiencies
Refueling
Name the main reason why hydrogen is not yet being used in aviation.
What other difficultie occurs in the adaption?
State:
The main advantage of electrical/hydrogen concepts
The main difficultie for both
The main environmental problem
Explain the concept of a Ram-jet
What needs to be installed additionally for the concept to work.
Name the three inlet concepts for ram-jets
Name the three main use-cases for ram jets.
Explain the special feature of the P&W J58 hybrid engine
Explain the concept of the Scramjet
What is a thrust rating?
Why are they needed?
Name the three certified and the two not certified ratings.
Explain
Maximum take-off thrust
Go-around thrust
Maximum continous thrust
Explain the maxiumum climb thrust and the maximum cruise thrust.
Explain the difference between thrust ratings and airline guidelines
What is a thrust curve?
Explain the T/To - M Diagramm
Thrust curve of turbo-jets
Typical 2-spool turbo-fan thrust curve
Last changeda year ago
