The Physics of Mandalorian Jetpacks (Hint: They Aren’t Jetpacks)

1 year ago 134

Let’s say you don’t need to fly quite so far. What about a jet engine? These are the things you mainly see on commercial airliners, but very small jet engines can also be used to make a real-life jetpack.

Just like rockets, jet engines produce thrust by shooting mass out the back, which is mostly just air. The energy comes from combusting jet fuel, which is similar to kerosene and is made from petroleum. The increase in the momentum of this ejected matter produces a forward-pushing force.

There is a big difference though: The jet engine sucks air in through the front of the engine. The oxygen in this air is used in a combustion reaction with the fuel to provide energy that increases the exiting speed of the air-fuel mixture. This means that the jet engine only needs to carry fuel, and not oxygen. However, this also means that the jet engine can only work in an environment that has its own oxygen. It won't work in outer space; it won't work underwater.

Well, what about the Mandalorian jetpacks—are they jet engines or rocket engines? I'm going to say they are rockets. First, you need to bring air in for jet engines to work, and you don't really see an air intake on the top of the jetpack. (Maybe it's just super small.) Second, we have seen that these jetpacks work underwater, like when Bo-Katan went underwater to save Din Djarin in the Living Waters on Mandalore. That rules out jet engines.

So, I'm declaring these jetpacks to actually be rocket packs. But since “jetpacks” sounds cool, we can continue to use the term, even though we know it's wrong.

Rocket Thrust

Let's make some approximations in case we ever want to actually make a jetpack like we see in the Star Wars universe. We can look at scenes in The Mandalorian to see how these flying machines perform.

The first thing you are going to want to do with a jetpack is to just hover above the ground. I mean, what better way to demonstrate your superiority over other people than to just rise above them and stare down as they stand helplessly below you? In this type of move, you would have an acceleration of zero meters per second per second. Newton's second law says that the net force is equal to the product of an object's mass and its acceleration. So, an acceleration of zero means the net force must also be zero.

For a hovering Mandalorian, there would be two forces. There's the downward-pulling gravitational force that we can calculate as the mass (m) multiplied by the gravitational field (g). Then there's the upward-pushing force from the jetpack (the thrust). So, if we just estimate the mass and gravitational field, that will give us the thrust force needed for hovering.

The mass seems like a simple estimation. A typical adult human would have a mass of about 75 kilograms. Of course, a Mandalorian wears armor and a jetpack. Let's just say this other stuff has a mass of 25 kg, for a total of 100 kg, which is a nice number.

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