Contragravitic

Earthian flight engineers have harnessed chemicals and fire and are hoping to harness the atom. But the CFM is evidently driven by a vastly superior form of energy which permeates it with contragravitic influence. The whole thing is nebulous; fabulous; fantastic. To Earthians with inquiring minds it often becomes an irresistible challenge[.]

Source: wiktionary

A true contragravitic vehicle, the Kodiak's substantial element zero core allows flight by entirely countering the vehicle's mass.

Source: wiktionary

Kane played around with the light globe’s control until he induced it to fly through the open hatch. It was fascinating to watch the device, which flew easily and quickly yet never let itself get closer than twenty or thirty centimetres to any surface. It clearly contained a contragravitic drive, but anything so small was unknown on Russalka. That it wasn’t even new technology to the Terrans was unsettling.

Source: wiktionary