rotor

Mazda built, raced, and won Lemans in 1991 with a 4-rotor equipped car called the 787B.

A uniform rod is not a good analog for a rotor blade.

The pictures only show the tail section -- that's the rear rotor in the photos..

If you're high enough, you can get enough rotor speed to turn that into enough lift to slow down the drop.

Ask a RX8 owner about rotor apex seals sometime.

The action of unspooling the cord and pulling on the rotor hub drives each rotor to overcome the drag force.

I don't like the look of that helicopter with flimsily attached wooden rotor blades.

How does this perform cross wind compared to a traditional micro quad?That main rotor will act like an umbrella does in a gust of wind.

The rotational inertia of the rotors is proportional to the length of the rotor blade to the fifth power.

Mass is not linearly proportional to length, because a longer rotor needs to be a lot heavier to be structurally sound.

Another idea that is being researched is having multiple quadrotor copters flying in co-operation.

He quickly burst the concept by pointing out to me that his autonomous helicopter has a 6 foot diameter rotor made of carbon fiber.

" It doesn't inertially support itself in the air until the rotor is spun up, and the rotor can only be spun up when it's fully constructed between the endpoints.

In a normal landing the rotor downwash would spread out across the ground but in this case the walls channeled the moving air back up and into the rotor again, causing it to lose lift.

You can fix this by turning each of the 4 rotors into a conventional helicoptor rotor with collective pitch control, but at that point it makes sense to just go with a helicopter.

The multi-rotor drones are basically uncontrollable without computers; you need a reasonably powerful processor, which in turn means a fairly high-capacity battery.