Flights in San Francisco

Clarify question

• Assumed - we are talking about an average day. Nothing to with time of the year

‍

Required numbers

• Number of runways operational
• Operational time
• Time between each landing / take off
• Un-suitable weather and wind
• Is the airport saturated - close to operational capacity?

‍

Estimating the numbers

• Total runways = 4. At a given time, mostly only 2 are used
• Peak operations are for 18 hours. Assuming rest 6 hours operations are close to zero.
• One hour = 3600 seconds
• Time between landing / take off = 60 seconds
• Assume 50:50 distribution of landing and take off
• Unsuitable conditions for weather and wind = 10%
• Assuming airport has achieved about 80% of operational capacity

‍

Estimate with equation

• Number of landings = # of runways * peak operations (in seconds) * landing % * (100 - unsuitable%) * % of Operational capacity achieved / Time between landing or take off
• = 21836000.50.9*0.8 / 45 = 775 flights lands per day

‍

State your assumptions

• I assumed 60 seconds difference between each flight landing / take off.

‍

Sense Check

• 775 per day translates to 775 / 18 per hour = 43 per 60 minutes. Less than a flight per minute.
• You generally see at least one flight land in the airport every one minute during peak hour. So you are close, good to go

‍