Infinite Flight Glitch
The infinite flight glitch, often abbreviated IFG, is a technique in Jak 3 which can be used to gain unlimited height and fly for an unlimited distance. It is performed by using the Light Jak Flight ability and alternating flapping the wings and using the Light Jak Shield ability in a regular rhythm.
Historically, the infinite flight glitch was used in Palace Ruins and Dark ship to skip large sections, however its use has since become redundant, the former due to a Jetboard proxy being found, and the latter due to the Jetboard hover, a much faster alternative, being discovered.
Technical
Using this glitch drains light eco slowly, so it is only able to go an unlimited distance and height with the Infinite Light Eco secret unlocked. However, it can still go very far without the secret.
It is much slower than the Jetboard hover, but allows the player to change direction, ascend, and descend at will, making it the more versatile option for exploration prior to the discovery of cheat mode.
Discovery
The infinite flight glitch can be found documented in many articles across the internet. It is unknown who discovered it.
Other Notes