The website includes a video [0] that explains how it works in more detail too.
It's quite interesting how they evade issues with landing and lifting the plane, lifting the plane by shooting it off a rail seems like a common approach but landing it by catching it using a small hook at the tail of the plane isn't that common I presume.
On their website it says "Gas combustion vehicles break down, get stuck in traffic jams that prevent urgent response, and put human drivers at risk behind the wheel, particularly when the route is rough and treacherous. Zipline’s drones are battery powered and fly quickly and directly to their destinations, leaving ground vehicles behind."
That sounds like an unfair comparison, a more accurate comparison would have been to gas powered drones. Is it still the case for gas powered drones that they're more unreliable than electrical drones? It's probably because of the weight of a gas powered engine in such a small drone no?
Ok, the first 4 were lost but this is a huge journey with limited fuel and bad weather. And navigation was a problem too.
The big benefit of gas powered in larger vehicles is both the easy fast refueling and the higher energy density of fuel. Combustion engines for model airplanes are heavier than their electric counterparts because you can only scale things down so much, you still need to contain a constant fire and the associated pressure.
And in this usecase the slow recharge isn't really an issue anyway. It also makes sense for marketing reasons, being 'green'. Even though if fuel were used, you could probably run this entire company for a year on the fuel a semi truck would burn to drive 100km :) I don't think it would be a bad thing for the environment if a company like this would use fossil fuel, it's still a lot less wasteful than the alternatives.
I wonder if a pulse jet (as used on the V-1) would be an option?
I've seen hobbyist level plans for them, and a pulsejet requires zero moving parts, so reliability should be excellent. The geometry of the engine does all the work.
I doubt slow recharge is even an issue since they can just pop in a new charged battery pack and put the depleted one on a charger. With swappable battery packs a drone can be relaunched within minutes.
> landing it by catching it using a small hook at the tail of the plane isn't that common I presume.
A lot of military drones have a hook at the end of one wing, and they hang a vertical wire under tension from a boom arm, with a differential gps receiver at the top of the wire. Ends up it's all accurate enough for the drone to catch the wire. I presume zipline went with their more complex approach as wings strong enough to just snag and stop would be past their weight limits.
> That sounds like an unfair comparison, a more accurate comparison would have been to gas powered drones.
It's a comparison for customers, showcasing the difference between zipline's solution (electric drones) and the existing solution (gas trucks) to the problem zipline is trying to solve (medical logistics). If gas drones or electric trucks were to enter the space then it should be updated.
It's quite interesting how they evade issues with landing and lifting the plane, lifting the plane by shooting it off a rail seems like a common approach but landing it by catching it using a small hook at the tail of the plane isn't that common I presume.
On their website it says "Gas combustion vehicles break down, get stuck in traffic jams that prevent urgent response, and put human drivers at risk behind the wheel, particularly when the route is rough and treacherous. Zipline’s drones are battery powered and fly quickly and directly to their destinations, leaving ground vehicles behind." That sounds like an unfair comparison, a more accurate comparison would have been to gas powered drones. Is it still the case for gas powered drones that they're more unreliable than electrical drones? It's probably because of the weight of a gas powered engine in such a small drone no?
[0] https://www.youtube.com/watch?v=jEbRVNxL44c