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commercial passenger aircraft worldwide

I would like to share my approach to the question number of commercial passenger aircraft worldwide.

1. #Passengers per year / 2. #Passengers with one aircraft per year.

1.1. #Passengers in developed countries + 1.2. #Passengers in undeveloped countries
to 1.1. => 1.1.1. #Passengers per year for leisure flights + #Passengers per year for business trips
1.1.1 
Assumption: every 5th lives in a developed country => 1.6b., 10% belong to the upper income class, 50% to the middle and 40% to the lower.
upper class: 160 m; of the upper 10%, each flies 2x per year (assumption based on personal observations)
middle layer: 800m; from the middle layer everyone flies 1x per year - 1x every 2 years = on average 0.5 per year
lower layer: 640m: from the lower layer everyone flies every 5 years => 0.2x per year 
= 320m + 400m + 128m = 888m passengers per year for leisure flights

Business trips: 50% of leisure flights = 444m

= approx. 1.3 b passengers per year

1.1.2. 
Assumption 4/5 live in undeveloped countries and only 5% of them can afford to fly = 320 mio, people fly 1x every 2 years (assumption based on personal experience / reading) 
= 160m passengers per year

1.1. = approx. 1, 5b passengers per year


1.2.#passengers on one aircraft per year = #passengers that fit on average on one aircraft x #flights per year per aircraft wing

Assumption an average passenger aircraft has capacity for 300 passengers

Operating days: 36 (5 days for maintenance and breakdowns)
14h / day an aircraft flies from Frankfurt to New York) 
Assumption: 80% are domestic flights 20% (based on observations at the airport)
=> 4.5 x 0.8 + 1.5 x 0.2 = approx. 4 / day 
4 x 360 = 1,440 / year

300 x 1,440 = approx. 430,000 passages per aircraft per year

1.5 b / 430,000 = approx 3,500 aircraft 
 

2
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4
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Top answer
Ian
Coach
on Apr 16, 2023
Top US BCG / MBB Coach - 5,000 sessions |Tech, Platinion, Big 4 | 9/9 personal interviews passed | 95% candidate success

Hi there,

I think overall you've done a nice job here!

8 or 9 out of 10!

Here's what I like:

  1. Overall approach is logical (# of passengers ==> flights ===>planes)
  2. You have estimated not assumed (even though you said the word assumed…please avoid using that word!)
  3. Your segments mostly make sense
  4. Your numbers are reasonable
  5. I love how you split domestic + international

Some small edits:

  1. Careful cutting out middle income countries (China, Brazil, etc. have way more than 5% of their population flying…)
  2. Careful saying upper class only flies twice a year - that's so low!

Otherwise, excellent.

Hagen
Coach
on Apr 17, 2023
#1 recommended coach | >95% success rate | 8+ years consulting, 8+ years coaching and 7+ years interviewing experience

Hi there,

I would be happy to share my thoughts on it:

  • First of all, I think both your overall, very nuanced approach and most key assumptions for this market size estimation are great.
  • However, I think that your assumptions for the frequency of flights of the "upper class" and the share of the population in "undeveloped" countries who are flying at all are both significantly too low.

If you would like a more detailed discussion on how to best prepare for your upcoming interviews, please don't hesitate to contact me directly.

Best,

Hagen

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