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Weight buildup

1. Passenger = 77 adult males

To consider the worst case scenario which is the heaviest possible case, all passengersare considered to be adult and male.

Total weight of passenger = 15400 lbs.

2.

Luggage for 1 person = 2 unitsMaximum weight for 1 luggage = 70 lbs.

Maximum weight for luggage = 10780 lbs.

Total payload weight = 26180 lbs.

3. Weight of crew = 2 flight attendants + 2 crew members FAA has regulated the number of crew for transport aircraft. Based on FAR Part 125,

Section 125.269,for airplanes having more than 50 but less than 101 passengers, two flight

attendants are required.

FAR Part 119, section 119.3:Crew for each crew member required by the Federal Aviation Regulations (A) For male

flight crewmembers--180 pounds. (B) For female flight crewmembers--140 pounds. (C)

For male flight attendants--180 pounds. (D) For female flight attendants--130 pounds.

(E) For flight attendants not identified by gender--140 pounds.

Total weight crew = 750 lbs

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Mission profile

Boeing 737-100 as a reference modal Conventional type, turbofan.

Initial take-off weight estimations

The data unknown now is for cruising and for loitering. Fuel weight fractions for these mission segments are estimated based on the statistics. Table

above illustrates typical average ratio values for fuel fractions of take-off, climb, descent, andlanding.

Loiter

DescentClimb

Take-off

Cruise

Landing

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Cruising ratio,

Where,

By using historical data, Bombardier Q400, maximum range is 1600 mile, so for this preliminarydesign studies, we take1500 mile as cruising range.

Since we are in preliminary design stage, and the aerodynamic aspect of the aircraft and alsopropulsion system are not determined yet, so we resort to historical value and employ the data

for similar aircraft for

Taking From Flight Mechanics,there are differences between an economic cruising flight and a

flight to maximize range.

o Almost no aircraft is cruising to maximize the range, since it ends up having a longertrip and have some operational difficulties. Most transport aircraft are

recommended to fly with the Carsons speed that is 32% higher than the speed for

maximizing range.

o On the other hand, in a cruising flight with the Carsons speed, the lift-to-drag ratioslightly less than the maximum lift-to-drag ratio; i.e.:

o In a cruising flight, the maximum engine thrust is not normally employed. This is to

reduce the cost and the engine specific fuel consumption (C).

From table below we can get specific fuel consumption

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In general, the unit of C in the range equation must be 1 over time unit (e.g. 1/sec). Taking Turboprop,

Cruise Weight Fraction, Loitering ratio,

Where,

Taking

Taking high bypass ratio Turbofan, The speed for maximum endurance (VEmax) for a prop-driven aircraft happens when the aircraft isflying with the minimum power speed. Since the aircraft has not yet been fully designed at preliminary

design phase, the calculation of minimum power speed cannot be implemented. Hence, the

recommendation is to use a reasonable approximation. The minimum power speed for most prop-

driven aircraft is about 20% to 40% higher than the stall speed.

Loitering Weight Fraction,

Now we can calculate After that we can calculate Next start to calculate

Where a and b are found in Table below and the assumption is that the either aircraft structure or

majority of aircraft components are made up of aluminum.

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Taking a and b as -8.2e-7 and 0.65

By using all the data required, we can finally calculate our

(

)

The following two equations must be solved simultaneously. This is a trial and error technique, as

shown in Table below. It is observed that after 15 trials, the error reduces to only 0.2% which is

acceptable. This technique produces a similar result (WTO = 174930 Ib)

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The iteration process,

Reference

https://www.google.com.my/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&ved=0CDUQFjAC

&url=http%3A%2F%2Ffaculty.dwc.edu%2Fsadraey%2FChapter%25204.%2520Preliminary%2520Design.

pdf&ei=BPJiUvrzDYrqrAep8oDIDg&usg=AFQjCNE4r1T4FQR4STAZlOSrWGhpHsy3kg&bvm=bv.54934254,d

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