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Comment by bsamuels | Hacker News Reader

I want to know how big the motors are going to be compared to the Mavic Pro. I've flown 5" race quads that were <250g and working against the wind can be a constant battle if you have gusts >10mph.

Traditionally DJI drones have had very underpowered motors so they can get those high flight time numbers; seeing the 30 minute flight time quote here doesn't give me much confidence that it will fly well with anything other than perfect wind conditions.

I can't wait to tear one apart and see what kinds of compromises/trade offs they've made compared to their larger drones.

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It's not a race drone. That's a completely different audience. What do you mean underpowered? Compared to what?

possibly to hold position in wind?

And doing so without losing altitude.

A drone needs to tilt to work against the wind, but this also increases its wind loading.

Let's say you're flying a race drone in windy conditions. you're aiming for a gate that you're going to fly straight through when a large gust of wind hits. You now have to compensate for that wind to correct your trajectory, and that can take a LOT of thrust depending on how large the gust was and how fast you need to correct the trajectory.

It's possible for the maneuver to require so much sideways thrust that you will bleed some altitude and start to fall to the ground (granted on a racing drone this is probably measured in centimeters for most maneuvers, but you get the idea)

Racing drones usually have a thrust:weight ratio of 8:1 or so, but the large Mavik Pro has a thrust:weight of 2.5:1, and their smaller Spark a ratio of ~2:1. You need a minimum TWR of about 2:1 to be flyable.

If the Mavic Mini has a similar TWR as the spark, then it's very unlikely you'll be able to fly it in any sort of windy conditions.

ok and what does all of this looks like when you're not comparing it against a race drone? Parent comment makes a good point I think, in that the Mavic line has never been geared towards "race drones" so comparing/judging those models based on a certain category that they qualify themselves out of is kind of moot.

I'm in the market for a drone at the moment (eyeing the mavic air over the mini to be honest) for holiday type shots, all this racing stuff is pointless as far as I'm concerned. I can't figure out based on your comment whether the wind will screw a wide shot or not, it might not make it through a circle, but i'll never get this drone through this sort of activity anyway.....

If I have a drone with 8:1 TWR and I have to bump my throttle by 20% to compensate for wind, a drone that has a TWR of 2:1 is gonna lose altitude and fail to maintain position.

I realize now that the way I described it in my parent post doesn't make very much sense

I don't think you can do anything about the wind in a <10kg design.

I saw some quads with lateral DOFs that used swashplates and piston engines in the 40-50kg class, but then you basically have a helicopter with 4x the problems of a helicopter.

Can’t speak for this one, but I have the Mavic 1 and 2 and both can handle very high winds well IMO.

The full size Mavik drones benefit from having much more mass holding them against the wind. The amount of drone surface that interacts with the air scales roughly squared, and the mass scales roughly cubic.

A simpler way of stating it is that when you have a heavy drone and a light drone with the same thrust to weigh ratio, the heavier drone will be able to hold its position much easier than the lighter drone in a gust.

Sure, but it's a super-lightweight drone targeted at Instagrammers mucking around with it. I think giving up performance against strong wind would be a given. Their demo shots all look reasonably close to the ground.

I was responding to: "Traditionally DJI drones have had very underpowered motors" - I'm sure there are tougher drones out there, but underpowered for what? I shoot video and photo for commercial purposes with mine and find that it handles wind very well, rain too. Incredible given the size means you can fold it down into a backpack and not lug around a Pelican case.

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