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'Windmill': China tests world’s first megawatt-level airship to capture high winds
(interestingengineering.com)
This is a most excellent place for technology news and articles.
500 to 1,000 meters AGL is going to be a problem for aircrafts. You need remote areas to have no interference bc these are big balloons.
Paint the balloons red and put lights on them so aircraft don't hit them.
Why red? Paint it like a brick wall so they can pass through.
Because it makes the blood stains less noticeable.
/s