Question

The DFW International Airport currently operates with one runway. Airplanes arrive at a rate of 19 per hour and the average landing time is 2.5 minutes. The estimated average fuel consumption for an aircraft stacking in the air is 17 liters per minute, and a liter of fuel costs $7. What is the average cost of fuel burned by an aircraft waiting to land?  

Answer 1

Given data	Values	Units
No. of aircraft landing in an hour	19	hour
Landing time	2.5	minutes
Fuel consumption	17	liters/minutes
Fuel cost	7	USD
Solution	Value	Formula
No. of aircraft landing in a minute	0.32	No. of aircraft landing in an hour / 60
One aircraft landing in how many minutes	3.16	1/ No. of aircraft landing in a minute
One aircraft is landing in 3 minutes 16 seconds
For every aircraft landing time is 2.5 minutes
So, the total time each aircraft is in air (minutes)	0.66	3.16-2.5
Fuel consumption/aircraft (liters)	11.22	Total time each aircraft is in air * Fuel consumption
Fuel cost/aircraft (USD)	78.54	Fuel consumption/aircraft * Fuel cost

• 19 planes are landing in one hour on the runway, which means, 1 plane is landing every 3 minutes 16 seconds
• The landing time is 2 minutes 50 seconds for each plane, which means each plane is in the air for a net time of approx 1 minute (0.66 min)
• Calculating fuel consumption and fuel cost for this time in the air, we get average fuel burnt by an aircraft waiting to land is 78.54 USD

Excel file is attached