Retro Aircraft Revival

Though the Concorde made its final flight 20 years ago, interest has been growing in resuming supersonic air travel. Current prototypes aim to overcome challenges of cost, noise, and sustainability. NASA and Lockheed Martin are testing a model that distributes its sonic boom more evenly, reducing sound pollution. The private sector is also developing new models, and one company has already completed construction of a factory to produce supersonic jets in North Carolina. But there's debate over how environmentally friendly these jets can ever be, given their rate of fuel consumption. Though it remains to be seen how viable and pervasive supersonic jets will be, their usage could affect travel behavior, airport design, and climate change mitigation efforts.

Blimps are also seeing a possible resurgence. A number of prototypes and concepts are under development, including seven-pound mini blimps proposed as helicopter alternatives. Several companies have completed test flights or promise to soon. The broad applicability of blimps is not yet known, though this more sustainable form of aviation may have implications for tourism and long-haul freight transport.