An Airbus 310A with a mass of 140000 kg sits on a runway It

An Airbus 310A with a mass of 140,000 kg sits on a runway. It takes off and flies to an altitude of 10500 m with a speed of 850 km/hr. If aviation fuel provides 43 MJ of energy per kg, how much fuel is required? Ignore friction for now.

Answer: 426 kg

Now lets put efficiency and drag into the last question. Drag (friction) is on the order of 9.7x10⁴ N and the efficiency of a jet engine is roughly 30%. It takes an airbus roughly 75 seconds to get to its altitude and during that time it covers 17.5 km. Using the data from the previous question calculate the more realistic amount of fuel needed.

Solution

Doing the calculations, the amount of drag increases to work to be done, by 9.7*10^4 x distance

= 1697.5 MJ

The amount of fuel reqd in order to overcome this drag is about 3.95 Kg so total fuel reqd is about 430 Kg

At efficiency of 0.3, the amount of fuel needed is 430/0.3 = 1433.3 Kg approx