... for airship enthusiasts: how long would it take a 60kt-capable airship to reach destination against a 60kt headwind? No prizes offered.
My friend Tommy ferried the Goodyear blimp from Los Angeles to Phoenix to broadcast for a ballgame, so he had a big money deadline. The winds out of the north were so strong it took him five hours to cross the highway to get a mile to Blythe airport.
When LTA can be faster than sustained low altitude winds, then they will have a better chance of viability.
They have been using heliostats for logging in the US Pacific Northwest for for more than 20 years. Sikorsky Skycranes, too.
GB