Wrong County
Last time I checked Farnborough was in Hampshire not Surrey so how is it Farnborough built but designed and manufactured in Surrey?
The Ministry of Defence has bought a third solar-powered Zephyr-S surveillance drone for £4.3m, and says it “performs more like a satellite than a conventional UAV”. With its 25 metre wingspan covered in solar panel cells, this latest Zephyr-S is the third unmanned aerial vehicle (UAV) to be delivered as part of the MoD's £13m …
My guess is transporting a fully built plane with a 25m wingspan is hard. Far easier to design and manufacture the components in Surrey and then do the final build (bolting it together) in a hanger at Farnborough airport. That or some parts are designed and manufactured in Surrey others are manufactured in Farnborough, or perhaps just sloppy journalism, take your pick.
Very different flying over Arizona in summer and Scotland in winter. Storing enough power during a long day to get through a short night may not be difficult but when the numbers reverse impossible.
So it could end up flying continuously through June but not lasting a single day/night in December.
It won't even fly one day if it can't gather enough surplus energy during daylight hours to keep it aloft after dark.
The can't be allowed to descend from the high altitude otherwise they're hazardous to everything else in the airspace.
Once you have a week in the air over Arizona there's no reason you can't fly for "12 months" (unless that 45 days happens to be centred on Jun 22 - in which case you might find it can't stay aloft in December.)
This drone is for airliners to report their positions. We need to deploy maybe millions of this drone to receive pings from all for airliners. Remember the MH370 missing boeing jet? It only pinged 2 satellites every hour, and when it went missing, the search area was narrowed to, like, 3 million square miles. If we had millions of this spy planes all over the world, we would have pin point the plane.
The original prototype (built prior to Airbus aquiring the Zephyr business) flew continuously for two weeks without landing, and as I understand things, it didn't need to land when it did, it was just that the agreed trial period had finished. 45 days isn't a stretch for an improved design.
I have no doubt that it can: 1) fly at 70,000ft; 2) fly for 45days; 3) carry a 5kg payload, but I bet it'll turn out that it can't do all three at the same time. I even have doubts that it will be able manage any two at the same time.
(This is not based on any deep knowledge of aero-tech, just my experience of UK military projects.)
In addition... setting aside for now the planned replacement of TETRA with 4G I cannot see any useful purpose being servied by fitting this thing with TETRA equipment. To what possible end? Even flying at 35,000 feet would be pushing it for communicating with small portable terminals with 1 Watt maximum power and helical aerials; even vehicle installations are limited to 1 Watt as well. And TETRA systems tend communicate "sideways" not up and down and that would reduce the effectiveness as well. At 70,000 feet the range would be simply too great.
At the same time a TETRA transmitter on a drone could cause trouble by accessing cell sites over a huge area; IIRC helicopter installations (obviously flying at more modest heights) caused difficulties that required a rethink over how airborn access to TETRA had to be organised.
Sounds more like a marketing ploy than a serious proposal.
"Even flying at 35,000 feet would be pushing it for communicating with small portable terminals with 1 Watt maximum power and helical aerials"
It really shouldn't be a huge problem, given that amateurs can work the ISS, orbiting at 400,000 m, with a 5 watt 2m / 70cm handheld transceiver.
Note that an amateur directly under the ISS is working with a disadvantage due to distance of about 400 times compared with a UAV at 20,000 m - nasty, that inverse square law.
It's a fractal thing: Keep zooming in and terrorists, communists, russian agents and those pesky "not-at-the-present sponsored-by-us"-jihaddis will keep popping out right down to Planck-scale resolution.
Maybe beyond Planck - except now they got tentacles.
"Get many terrorists and enemies of the state in the Arizona desert, do they?" Ever stop to think that the Arizona desert offers a very similar operational environment to Afghanistan and the Middle East? Or that the UK has used conventional drones for flying defensive observational patrols over bases in Afghanistan, a role the Zephyr could do non-stop for weeks at a time? Ah, didn't think so.
"....I don't think so...." Ah I can guess what the problem there is. Nevada is actually a very good training environment for desert flying, which is why the RAF routinely sends pilots and planes out to Nevada to gain experience. Ah, experience - beats wishful thinking every time!
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