How many commercial flights fly in a day?

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How many commercial flights fly in a day?

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absahai · Answer 1 · 2022-05-08T11:33:23+0000

Assumptions:

We are talking globally
We are talking about passenger flights and nothing else

No. of flights flying in a day will be directly proportional to the airport capacity of making the flights fly i.e.

the number of available runways
how busy is the airport and hence runway capacity

	# of airports	# of runways	Frequency of take-off	Total flights per day
Heavy Traffic (HT)		4	Every 5 minutes
Heavy Traffic (HT)		2	Every 10 minutes
Intermediate Traffic		2	Every 15 minutes
Intermediate Traffic		1	Every 20 minutes
Low Traffic		1	Every 30 minutes

Total number of airports

Airports are generally directly proportional to a country’s land mass - the bigger and developed a country is - the more airport it has. NA has phenomenal number of airports and boasts airports with most runways Chicago 8, Dallas -6 but not many airport even have 2 runways, for e.g. London Heathrow airport has only 2 runways.

To get get to the number of airports globally I will segregate the countries in three groups.

North America - (Reason for keeping NA as a separate group as it has phenomenal number of airports 5000 and hence qualifies as a standalone entity. Combining it with any other group will heavily skew the group characteristic)
1. 50 HT airports with avg of 4 runways
2. 50 HT airports with avg of 2 runways
3. 400 IT airports with avg of 2 runways
4. 1500 IT airports with avg of 1 runway
5. 3000 LT airports with avg of 1 runway
Top 9 countries with maximum area (Russia, Canada, China, Brazil, AUstralia, India etc)

On an average a country in this group have ~200 airports each i.e. total of ~2000 airports. Breakup:

HT with 4 lanes (5%) = 100
HT with 2 lanes (15%) = 300
IT with 2 runways (20%) = 400
IT with 1 runway (20%) = 400
LT with 1 runway (40%) = 800

3. Rest of the world (190 countries) have average of ~50 airports each i.e. a total of ~10000 airports. Going by the same distribution:

HT with 4 runways (5%) = 500
HT with 2 runways (15%) = 1500
IT with 2 runways (20%) = 2000
IT with 1 runway (20%) = 2000
LT with 1 runway (40%) = 4000

Lets do the math:

	# of airports	Runways	Frequency of take off	Frequency per day	Total flights per day
Heavy Traffic (HT)	50+100+500 = ~ 700	4	Every 5 minutes	12*24 = 288 ~ 300	7003004 = 840,000 ~ 900,000
Heavy Traffic (HT)	50+300+1500=~ 2000	2	Every 10 minutes	6*24 = 144 ~150	20001502 = 600,000
Intermediate Traffic	400+400+2000~ 3000	2	Every 15 minutes	~100	30002100 = 600,000
Intermediate Traffic	1500+400+2000 ~ 4000	1	Every 20 minutes	~75	= 4000175 = 300,000
Low Traffic	3000+800+4000 ~ 8000	1	Every 30 minutes	~50	= 400,000

Total flights per day = 2,800,000

Self check: This number is way off. I overestimated number of airports with 4 runways and 2 runways. This number is far far less. ALso, I think I can skip altogether 2 runways for Intermediate traffic as that would be covered in the Heavy traffic one.

The actual number is ~ 100,000 flights