I am not a professional travel agent. I like travel (a lot) & have been a passenger on many commercial airline flights. My reference to “bluer/blue-er” flights in this post means better for air quality/the atmosphere. Aiming for constant improvement there. Following are some of my thoughts after what I have read (on internet) as recent good news for eco-aviation / bluer flights. Your own thinking & conclusions are also necessary.

Boeing may be partly offsetting their current woes in the news with something I read about this week. As apparently reported in an online tech publication: “NASA & Boeing have teamed up to develop an ‘ultra green’ aircraft”; a “hybrid electric the size of a Boeing 737”. With electric engines included, it is said that it could be “70% more efficient than its all-fossil-fuel counterparts”. Reported: that it would have foldable wings. Though it is said that this concept aircraft may not be realized until: “between 2030 & 2050”. May they be encouraged to speed that timeline up for all of us.

Some current (general) problems:
– Consider the “technically already outdated Airbus A380” with 4 engines that “burn 32 tons of kerosene every hour”.
– & Consider jet contrails (short for “condensation trails” or vapour trails: line-shaped (cirrus) clouds that may be produced by aircraft engine exhaust or changes in air pressure). May be drawn by legacy jets still flying today. Often created at common flying altitude (~ 6 miles) & said to be particularly harmful to the climate. Because they can intensify the greenhouse effect. 

Sustainable Aviation Fuel (“SAF”) or partial SAF may currently be the best option known for long-haul flights. Shorter flights are now getting other options: 

Hydrogen Planes: Progressing past Sustainable Aviation Fuel (“SAF”), a “next step…[that] could be much larger & more radical”: propulsion utilizing hydrogen. There are several estimable entities working on the (many?) unsolved challenges. Hydrogen fuel could be especially clean/sustainable “if it is produced with the help of solar or wind energy”. & Said to be “particularly suitable for regional & short-haul” flights. 

E-Planes: The potential(s) of electric power (currently, for regional & short-haul flights) could be huge. Battery-powered electric planes: probably ready sooner than hydrogen-fuelled planes. Smaller planes, for now. A Wikipedia Wiki currently lists (I counted) almost 90 (!) aircraft “whose primary flight power is electrical”. The first credited “crewed free flight by an electrically powered aeroplane”: in 1973. Most crewed electric aircraft today though, are still only experimental prototypes. A “Swedish company .. is currently developing… one with 30 seats”. & I read that back in Sept. 2017, UK’s Easy Jet announced it was developing an electric 180-seater, for 2027. “Sluggish charging” is reported to be a big challenge for electric planes. For electric aircraft feasibility, it appears essential that power storage be improved. “Further advances in battery technology” needed. I believe I have seen news that advances are starting to happen. & A few E-planes are already in production.

Future Airports: There can be an “almost complete absence of engine noise” in an E-plane. Then: noise might no longer be such a limiting factor for where we situate our airports of the future. Everyone, including residents currently living in flight paths and/or in proximity to airports, would likely much welcome that. Runways for E-planes are likely to be shorter, lowering the general cost of future airports.

Can air travel possibly become a “greenest means of transport”? (& sooner rather than later?). It appears that many are working towards that goal. Regarding short haul travel, a “bold [new] vision is for flying … more environmentally friendly than train travel”. Hopeful stat.: by 2023, the number of sustainable aircraft concepts (of all kinds) under development .. was estimated at up to 700.  & Also: “fully electric airships are expected to be available again” within about a decade.