Aircraft Design MCQ – Conceptual Sketch Sizing – Takeoff-Weight Buildup
1 - Question
The subsequent step after the requirements in conceptual design phase is _____
a) design take-off gross weight
Explanation: The Conceptual design often begins with the mission requirements of the aircraft. Once the requirements are set, next step is to estimate the design take-off gross weight. This is done due to the fact that weight will directly affect the vital performance parameters.
2 - Question
The “Design take-off gross weight” and “maximum take-off weight” are always interchangeable.
Explanation: During the conceptual design process design take-off gross weight is calculated based on requirements. Based on the mission profile we can use terms interchangeably in general. However, it is not the case for each and every mission.
3 - Question
Design take-off gross weight includes ______
a) only fuel weight
b) only crew weight
c) only payload weight
d) crew, payload and fuel weights
Explanation: Design take-off gross weight is total weight of the aircraft to be designed. It is the combination of all possible weights of an aircraft. Hence, from the given options, it is easy to say that it includes every type of weight.
4 - Question
Avionics systems are an example of ____ weight.
Explanation: Crew weight is the weight of all crew members. Passenger weight includes the weight of the passenger. Empty weight will include avionics, subsystems, power plant etc…
5 - Question
Take-off gross weight of an aircraft is summation of _____
a) empty and payload weight
b) fuel, payload, crew, empty and miscellaneous weight
c) fuel and crew weight
d) only passenger and crew weight
Explanation: Typically, take-off gross weight is the maximum possible weight of aircraft during take-off. It includes weight of crew, passenger, fuel, empty and some miscellaneous weight.
6 - Question
In general, the fuel weight is represented by a fraction of total take-off weight.
Explanation: For given Aircraft, we know the typical values for crew and payload. However, we do not know fuel weight as well as empty weight. Hence, they are represented in terms of the fraction of total take-off weight. This can simplify the calculation.
7 - Question
A general aviation aircraft is flying with crew load of 115lb, payload of 220lb and fuel weight of 100lb. Find out the design take-off gross weight of the aircraft, given 95lb empty weight.
Explanation: Given, Crew load = 115lb Payload weight = 220lb Fuel weight = 100lb Empty weight = 95lb Now, the design take – off gross weight is given by, W0 = Wcrew + Wpayload + Wfuel + Wempty W0 = 115+220+100+95 So, W0 = 530lb.
8 - Question
A jet airliner aircraft is flying with crew load of 150kg, payload of 520lb and fuel weight of 500lb. Find out the empty weight if design take-off gross weight of the aircraft is given 1525lb.
Explanation: Given, Design take-off gross weight, W0 = 1525lb Crew load = 150kg = 150*2.205lb = 330.693lb Payload weight = 520lb, fuel weight = 500lb Now the design take – off gross weight is given by, W0 = Wcrew + Wpayload + Wfuel + Wempty 1525 = 330.693 + 520 + 500 + Wempty So, Wempty = 174.307lb = 79 kg.
9 - Question
Cessna 172R has total gross weight of the 1110.98kg with fuel capacity of 210 kg and weight of crew and passenger is 125kg. Find out empty weight fraction.
Explanation: Given, Design take-off gross weight, W0 = 1110.98kg Crew and payload weight = 125kg Fuel weight = 210kg. Here, first we need to find the empty weight and then we can find empty weight fraction. Now the design take – off gross weight is given by, W0 = Wcrew + Wpayload + Wfuel + Wempty 1110.98 = 125 + 210 + Wempty So, Wempty = 775.98kg Hence, empty weight fraction = (Wempty / W0) = 775.98/1110.98 = 0.6984.
10 - Question
A Jet transport aircraft is flying with crew load of 175kg, payload of 1400kg and fuel weight of 500kg. Find out Fuel to empty weight fraction, if design take-off gross weight of the aircraft is 5600lb.
Explanation: Given, Design take-off gross weight, W0 = 5600lb = 2539.6825kg Crew load = 175kg Payload weight = 1400kg, fuel weight = 500kg Now the design take – off gross weight is given by, W0 = Wcrew + Wpayload + Wfuel + Wempty 2539.682 = 175+ 1400 + 500 + Wempty So, Wempty = 464.682kg Fuel weight fraction = Wfuel / W0 Empty weight fraction = Wempty / W0 Now fuel to empty weight fraction = Wfuel / Wempty = 500/464.682 = 1.076.