Airbus Zephyr 8 solar powered UAV is up.
By - lothcent
been up since the 16th.
things I find amazing is that loiter speed that I've seen down around the 10-11 knot range while at 55k alt.
but I am confused by the payload capability
(11 lbs) and what good this plane is at other than flying high, slow and for quite a long time.
the glossy press releases all point out possible uses- but a 11 lb payload capability really strikes all the glossy promises off unless I am missing something
for remote sensing / observation, you can actually do quite a lot with 11 lbs
main thing this is competing with is observation satellites in low earth orbit, where weight is also a huge concern, so there's already been a huge push to make components smaller and more power-efficient (since your entire payload is also going to be drawing from the solar panels)
the big downside of satellites in LEO is they have a ~90 minute orbit. so if there's one particular region of the world you care about, your satellite gets maaaybe 10 minutes over that region, then 80 minutes over other parts of the world you don't care about. and depending on the orbital inclination it may or may not be back over your area of interest after that 90 minute orbit, either. you also need a network of ground stations around the world if you want to stay in constant contact with it...or a complicated system where the satellite uses geosync satellites as relays to the ground.
you can of course mitigate that by launching lots of satellites, but that gets real expensive, real fast. in theory you could send a satellite up to geosync orbit and give it a constant view of one part of the Earth, but that's also *hugely* expensive and requires much more powerful optics to get the same resolution.
with this, you've got nice slow loiter capability over a large area, with no wasted time over the rest of the globe. you can upgrade / tweak / swap out the payload while it's on the ground, which isn't possible for current satellites ([except for highly classified military stuff...](https://en.wikipedia.org/wiki/Boeing_X-37)). you're also shielded from a substantial amount of radiation compared to LEO, so you don't need components to be as rad-hardened, and if they fail you can just swap them out on the ground.
also, they'll keep improving the weight limit. components are only going to get smaller and lighter at the same time as the payload capacity keeps increasing.
Sorry, missed the previous post.