Ion flight.
http://news.mit.edu/2018/first-ionic-wind-plane-no-moving-parts-1121
Unlike turbine-powered planes, the aircraft does not depend on fossil
fuels to fly. And unlike propeller-driven drones, the new design is
completely silent.
“This is the first-ever sustained flight of a plane with no moving
parts in the propulsion system,” says Steven Barrett, associate
professor of aeronautics and astronautics at MIT. “This has
potentially opened new and unexplored possibilities for aircraft which
are quieter, mechanically simpler, and do not emit combustion
emissions.”
The team’s final design resembles a large, lightweight glider. The
aircraft, which weighs about 5 pounds and has a 5-meter wingspan,
carries an array of thin wires, which are strung like horizontal
fencing along and beneath the front end of the plane’s wing. The wires
act as positively charged electrodes, while similarly arranged thicker
wires, running along the back end of the plane’s wing, serve as
negative electrodes.
The fuselage of the plane holds a stack of lithium-polymer batteries.
Barrett's ion plane team included members of Professor David
Perreault’s Power Electronics Research Group in the Research
Laboratory of Electronics, who designed a power supply that would
convert the batteries’ output to a sufficiently high voltage to propel
the plane. In this way, the batteries supply electricity at 40,000
volts to positively charge the wires via a lightweight power
converter.
Once the wires are energized, they act to attract and strip away
negatively charged electrons from the surrounding air molecules, like
a giant magnet attracting iron filings. The air molecules that are
left behind are newly ionized, and are in turn attracted to the
negatively charged electrodes at the back of the plane.
As the newly formed cloud of ions flows toward the negatively charged
wires, each ion collides millions of times with other air molecules,
creating a thrust that propels the aircraft forward.
This was the simplest possible plane we could design that could prove
the concept that an ion plane could fly,” Barrett says. “It’s still
some way away from an aircraft that could perform a useful mission. It
needs to be more efficient, fly for longer, and fly outside.”
It's the newest thing, and since your caster is a giant electricity generator, they should be able to do this. Either with their fingers to look really talented, or with specially designed suits.
This has a rather unique and terrifying benefit that it is completely silent, so your lightning mage is also a perfectly silent flying assassin, able to go anywhere and hurl bolts on unsuspecting foes.
