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Comment by matsemann | Hacker News Reader

> The 20 min flight time is a lie, Joshua Bardwell measured 10 minutes hovering.

To be fair, hovering time is often lower than flight time for copters.

So 10 minutes up, then 10 minutes falling?

Anything with rotors generates extra lift when moving vs hovering, so it requires less power to hold altitude when moving vs hovering.

Imagine if you stopped the blades but the craft is still traveling forward... lift is being generated by the air flowing over one side of the rotor just liked a fixed wing aircraft.

At the extremes some full size helicopters can't climb straight up, they have to have forward motion to generate enough lift to climb. This allows use of a smaller motor to bring operating cost down.

In the case DJI drones the battery times are usually quoted with some amount of forward speed.. it generates a longer run time than a hover test.

There's also simply the effect of not staying in a downstream you created.

A drone/helicopter accelerates air downward, and it's easier to accelerate still air than air that's already moving downward.

in this case the drone is so fragile that the only way to get 10mins of flight from it without breaking it, is to hover

I dont know why this comment was downvoted I found it both funny and informative

It's obviously hyperbole - but the problem is that without the hyperbole, the comment communicates nothing substantive. How was it informative?

it informs you that you're going to crash it when you try to actually fly it, and it will break badly. fpv drone frames are usually made from thick carbon fiber, with replaceable arms, and are designed for durability and repairability and they still get wrecked in crashes. so even if i put it in a funny way, it's not as much an hyperbole as much as a fact: unless you're pretty much hovering, you're going to end up with a very expensive and unserviceable pile of broken electronics and plastic

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