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Comment by njoubert | Hacker News Reader

Ah, tailsitters. Everyone loves the theory, then the practical realities of the takeoff position exposing the entire wing surface to the prevailing wind quickly kills real-world applications. I remember back during the 3D Robotics heyday watching Chris Anderson repeatedly run down to set his tailsitter upright, take a few steps back, only to watch it fall over again.

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Martin UAV is looking like the one to beat in medium range right now, and it's a pretty slick tailsitter design. If I was a betting man, I'd say that it's going to eat ScanEagle's lunch sometime in the next few years, or get bought. Which, ugh, the latter seems more likely, sad to say.

I'm not with Martin, but scuttlebutt is that the flight controls take into account takeoff and landing winds, then use that to adjust the flight attitude on approach and takeoff, since the wind can add to the effective airspeed for rotation.

Once it tags the ground the flight procedures have it nail itself to the pad double quick. That's about the only dodgy part, but they've done it from the back of a speeding truck and it looked fine. Hell of a lot finer than "drive the plane into a rubber band hanging from a stick".

There are commercially available tailsitter UAVs primarily used for mapping purposes:

https://www.atmosuav.com/product/mapping-drone-marlyn?view=w...

It transitions into forward wing flight after take off. It does achieve a greater flight distance/flight time per battery compared to the same size of thing as a quadcopter, but NOT as great of endurance as something like a 2 meter wingspan VTOL with four lift motors + single thrust motor, such as:

https://www.foxtechfpv.com/foxtech-loong-2160-vtol-mapping-p...

I (as someone without a need for any drone and therefore without having looked at enough prices of drones to have any gut instinct here) was curious how much that first one you linked - the Marlyn UAV - might cost, since the company only says to contact them for pricing.

This page [1] suggests $17k, is that likely on the money (pun intended, sorry) or just a random scam site?

[1] https://volatusdrones.com/products/atmos-marlyn

don't think that's a scam site, though it probably has a healthy profit margin. that price is within the range of normal for a fully built surveying drone for use by people who aren't interested in getting into the technical details of pixhawk/ardupilot/arducopter stuff and building their own. They're sold to surveying companies, mining companies etc.

go look at pricing for the DJI Matrice 30 (M30) for some comparisons...

Can't you take off from a closed box? For landing the flight controller should be able to compensate for the wind and come down in a somewhat vertical position.

For vertical takeoff and landing the wing surface is mostly irrelevant, right? Seems like if you gave the rotors a “landing configuration” where they rotated 90 degrees you could lay the wing flat on the ground.

The wings look like they have smaller control surfaces the full wings are not. But to make cheap drones that are dropped or launches from a cheap taco holder its probably fine.

This is the distinction between tilt wing aircraft and tilt rotors. The former were explored in the 60s and found impractical. The latter took longer to develop but are now practical.

The original comment is spot on: hovering vertically with a big wing also vertical just doesn't work well in the real world. That said, the situation might be different for very small drones, for similar reasons to why you don't build full size quadcopters.

Movable motors would greatly increase the complexity and weight.

The Harrier, Osprey and the carrier variant of F-35 are real world aircraft that point the thrust vector at the ground for takeoff and landing, then rotate it to the back for forward flight.

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