A lot of the problems you bring up can be solved and will be, I've been working on long range multicopters so trust me I speak from experience.
At 200ft with low KV motors and big props they are nearly silent or at least quiet enough that they blend into the background. If you fly following surface streets you remove a lot of the "drone falling on someone possibility" and insurance can handle damage to cars if something were to go wrong. Keep in mind they can also be fitted with parachutes and airbags that can be deployed for safety.
Right now the biggest holdbacks are losing GPS lock (flyaways are not fun) sense and avoid (don't hit stuff) and battery life.
You can easily build a multicopter with current tech able to fly 5km+ and back in under 10min (I've done it) the issue is that due to the weight of the batteries you don't end up with much payload left to speak of. As better battery tech is rolled out and other stated problems are solved drone based logistics will be viable, I give it 5 maybe 10 years max and am very bullish on it.
Is there a reason that these use batteries rather than combustion engines?
Are you expecting the drones to use hardened GPS modules resistant to hijacking and not get DDoS'd by someone broadcasting fake GPS at their take off area?
I have been working on my quads since 2011 and have three.
Aside from their main downside (energy density), which is improving each year and now reaching 265 Wh/g, electric batteries provide many improvements. First of all, electric motors are more efficient than gas-powered motors. Secondly, gas-powered motors are fairly heavy, so you need a bigger and thus more expensive quadcopter. Thirdly, it is difficult to control a gas-powered quadcopter at the speed of an electric quadcopter.
TL;DR It's possible but difficult to make a gas-powered quadcopter, since it'll be heavy and difficult to control. At that point, it doesn't make much sense to use a quadcopter, since two of their biggest advantages are how easy they are to control and how light they can be.
Also, it would make no sense for you to "DDoS" a GPS module. DDoS = distributed denial of service. You're probably thinking of jamming (broadcasting garbage data so the GPS can't receive anything) or spoofing (broadcasting fake data.)
> Thirdly, it is difficult to control a gas-powered quadcopter at the speed of an electric quadcopter.
I disagree with you there. Collective pitch quadcopters with combustion engines have been done. With CP quads you lose one benefit of traditional quadcopters, which is their simplicity (basically, they're four electric motors with a computer that tells each one how fast to spin), but that benefit is more applicable to hobbyists than to commercial package delivery.
Ease of use, complexity and reliability. I'm referring to drones < 10kg. There's a point in large systems where gas becomes a more competitive option but for smaller multicopters it's not.
Interesting. But the real question we need to ask ourselves right now is: are these drones capable of delivering burritos? Because if so, imagine the possibilities...
At 200ft with low KV motors and big props they are nearly silent or at least quiet enough that they blend into the background. If you fly following surface streets you remove a lot of the "drone falling on someone possibility" and insurance can handle damage to cars if something were to go wrong. Keep in mind they can also be fitted with parachutes and airbags that can be deployed for safety.
Right now the biggest holdbacks are losing GPS lock (flyaways are not fun) sense and avoid (don't hit stuff) and battery life.
You can easily build a multicopter with current tech able to fly 5km+ and back in under 10min (I've done it) the issue is that due to the weight of the batteries you don't end up with much payload left to speak of. As better battery tech is rolled out and other stated problems are solved drone based logistics will be viable, I give it 5 maybe 10 years max and am very bullish on it.