# What is the typical fuel consumption per nautical mile of a mid-size aircraft carrier cruising at 20 knots ?

First in order to solve this, we must gather some statistics:

For one, let’s use an example plane (a lot of mid-size planes have different engines and body styles, so the calculations will be different for all of them).  I’m going to use the Boeing 787-8 for this equation.

Now, let’s find out the 787’s data (this is a wikipedia citation [first citation]):

Maximum fuel capacity: 33,528 US gal

Cruising Speed: Mach 0.85 (567 mph, 490 knots)

If we take the Maximum fuel capacity, and divide it by the Range, fully loaded statistic, we should find out the nmi/gal ratio: which is 4.38 mni/gal or knots/gal.

Since the “Cruising Phase” of aircrafts in general takes up most of the fuel consumption, the 787’s fuel will be mostly drained by that.

The deal is, this is a difficult set of calculations, as fuel consumption is generally a ratio per hour of a plane, not distance, or necessarily speed (That’s why you take the maximum flight ability and the maximum fuel capacity together).

A plane that cruises at 20 knots will probably be a completely different type of mid-sized plane, and will have different calculations altogether (which I could not find specific data on; hence using the 787).

There is a good forum for pilots that analyzes the situation completely (second citation).