If quadcopters would be better you would’ve seen countless designs for the military by now.

Quad Copters work well in toys and any similar application because they fly primarily based on their insanely high trust to weight ratio.

Helicopters don’t levitate on thrust.

Things simply don’t scale in this manner, the cost of the components isn’t even the issue here the cost of maintaining a system that is certified for manned flight is, buying a helicopter is cheap keeping it flight worthy is the expensive part especially when it comes to commercial application.

Literarily nearly every commercial aircraft has about as many maintanance hours as flight hours and in fact many have more.

Just to put into perspective here is what the Airforce considers an aircraft that is efficient to maintain:

>Reliability and maintainability are two outstanding benefits of the C-17 system. Current operational requirements impose demanding reliability and maintainability. These requirements include an aircraft mission completion success probability rate of 92 percent, only 20 aircraft maintenance man-hours per flying hour

While smaller aircraft don’t require as much as 20 hours per each flight hour they would still require plenty of it to make scalability very difficult.

Those things don't scale up. What works in a toy won't work in a larger aircraft. Look at rotor disk loading versus power efficiency for example.

To gain a better intuitive understanding of the problem, consider why we can't use selective breeding to create a mouse the size of a horse.

Sure, the mechanical components don't scale up. I wasn't referring to upscaling a toy drone. But, if - and it's an if until someone actually solves all the problems - someone comes up with an electric airframe that works well enough for personal transportation - then I think it's more likely than not to have economies of scale to kick in and drive the cost down together with commoditization of personal flight.

Sure, there are lot of if's there. But mainly my guess "an electric 'quadrocopter' will be cheaper for personal transport than helicopter" is based on two things: * it will become popular, hence driving unit costs down * the vehicle will be cheaper to operate than a combustion engine powered helicopter

I think there are two separate issues: electric vs. combustion, and quadrocopter vs. traditional helicopter.

> But mainly my guess "an electric 'quadrocopter' will be cheaper for personal transport than helicopter" is based on two things: * it will become popular, hence driving unit costs down

Why? Is this because of the electric part or the quadrocopter part and how does either make it more likely to be popular?

> * the vehicle will be cheaper to operate than a combustion engine powered helicopter

Again are you getting this from the electric aspect or the quad aspect, and what's the reasoning?

I don't know. I'm pretty sure lots of aeronautics engineers have an actual professional answer to this. I mainly hoped with my comment that someone that had actually ran the numbers could chime in.

Taneq's answer above sounds fairly credible so I'm probably wrong about this.