Hmmm. If, rather than flying close to sea level, you flew at high altitude (above commercial airliners), and kept it relatively small, I suspect that you could do this and no one would notice unless you told them.
Though at high altitudes the winds are such that it would be less of an airship and more of a steerable balloon.
This is an interesting article from a couple of days ago about tracking diy balloons long distance: https://spectrum.ieee.org/explore-stratosphere-diy-pico-ball.... Given the tracker can be built for $14 it might be worth it to test a version with just the custom hydrogen enclosure and tracker and see how far it gets.
A new sailing record was set recently, which didn't _quite_ beat 40 days - it took them 40 days and almost 11 hours.
If you've ever seen a SailGP boat flying up out of the water on their hydrofoils and doing 100kmh - imagine a 32m long 26m wide ocean going trimaran doing the same thing in a non stop circumnavigation of the globe. I think they _averaged_ 27knots or 50kmh!
And when the world was still flooded with money and the music was awesome (so 2004), Jeremy Clarkson did a series about inventions, one of them being the jet plane, and he flew commercial around the world in 120 hours: https://www.youtube.com/watch?v=o8D_UzMhjH8
> Finally, can it be flown legally? Most of the trajectory can pass over the oceans, but skipping land completely would take too much of a detour, and likely be incompatible with prevailing winds. Although the political climate may be hostile, it is still legal to fly civil craft over other countries.
Ha! It’s also going to be funny when he discovers going over India requires parallel diplomatic clearance by his embassy and if he misses the slot, bye bye record. Repeat problem for multiple countries along the route.
Fair points. I am aware that it is a UAV, and that there are some harsh regulations around the world (e.g. drones are completely banned in Morocco). I am also willing to accept my vast ignorance. I don't know exactly what regulations apply to an autonomous airship: balloon, UAV, recreational amateur aircraft? Actual laws for the handful of countries involved in the actual trajectory (Nicaragua, Thailand, Egypt perhaps) are not easy to find online. So I changed the first paragraph to:
"Finally, what are the legal implications of flying an airship drone over foreign air spaces? This very complex area clearly requires in-depth study and careful consideration, and it lies completely out of my depth. The primary objective is just to avoid being shot down since I'm not planning to visit any foreign countries in person, so allow me to just touch over the main issues."
Hydrogen containment: you might want to look at topping up hydrogen along the way. Have a small compartment inside the gas bag with lithium shavings and a small servo that can release water into this compartment.
You'll get about 1/15-th of the lithium+water mass as hydrogen. So if you want to replenish 1 m^3 of hydrogen at STP (or around 1/8-th of the gas bag volume), you'll need around 600 grams of reagents.
Though at high altitudes the winds are such that it would be less of an airship and more of a steerable balloon.
A new sailing record was set recently, which didn't _quite_ beat 40 days - it took them 40 days and almost 11 hours.
If you've ever seen a SailGP boat flying up out of the water on their hydrofoils and doing 100kmh - imagine a 32m long 26m wide ocean going trimaran doing the same thing in a non stop circumnavigation of the globe. I think they _averaged_ 27knots or 50kmh!
https://youtu.be/ffqhFyaCUFA
If you _haven't_ seen the SailGP boats and are curious, here's somewhere to start: https://youtu.be/BQWOoP-Iwn8
Also FYI the link to "Aves Æternæ" is broken.
PCAAD: Too Microsoftie.
- Piloted Intelligent Circumnavigation Airship for Research and Development
- Prototype Integrated Control Autonomous Route Drone
- Programmable Intelligent Circumnavigation Aeronautical Remote Device
- Piloted Intelligent Craft: Autonomous Route, Data-driven
- Primary Intelligence Control And Route Determination
- Precision Integrated Circumnavigation And Remote Deployment
> Finally, can it be flown legally? Most of the trajectory can pass over the oceans, but skipping land completely would take too much of a detour, and likely be incompatible with prevailing winds. Although the political climate may be hostile, it is still legal to fly civil craft over other countries.
So no, it's not legal in many ways.
"Finally, what are the legal implications of flying an airship drone over foreign air spaces? This very complex area clearly requires in-depth study and careful consideration, and it lies completely out of my depth. The primary objective is just to avoid being shot down since I'm not planning to visit any foreign countries in person, so allow me to just touch over the main issues."
You'll get about 1/15-th of the lithium+water mass as hydrogen. So if you want to replenish 1 m^3 of hydrogen at STP (or around 1/8-th of the gas bag volume), you'll need around 600 grams of reagents.