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Area of a plane in square meters

Hello,

I was doing an investment case earlier todayand was told to calculate the area of a plane in square meters. Suffice to say that I lost all confidence at tat point. How would you calculate the surface area of a plane? 

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Deleted
Coach
on May 07, 2018
Current partner @ Andreessen Horowitz (VC firm). Ex-Mckinsey, ex- strategy guy at Google.

So you'll just need to brush up a bit on your high-school geometry / trigonometry / mensuration.

Best to solve these by drawing it out on a piece of paper. Roughly, a plane is:

- a long cylinder of radius R

- wings

- few other parts but mostly negligible so mention them + say we'll ignore or add 10% to final ans.

For cylinder, the radius is obviously changing, but you can do a rough estimate of an average R that's midway between the min (at the nose) and max (at the center). Then surface area is 2*pi*r*length + some rough estimate of the two edges, say 5% extra.

For wings, it's a standard triangle roughly  right-angled. Assume the sides, and make an estimate.

HTHs

Deleted user
on May 07, 2018

Agreed with suggested approach. Do remember to multiply wings by four, not just 2 (top and bottom surface).

Also no need to specify whether the wing has a right angle (it does not) or not and put yourself in hot waters unneccesarely, just assume how much the wing is sticking out from the fuselage (height of triangle) and how long is where it attaches to it (base). Then area of triangle (whether with a right angle or not) is height*base/2.

Hope it helps,

Andrea

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