Apex Legends' new Legend, Valkyrie, is distinguished by her ability to fly around the map in bursts using her jetpack. Although the Legend has only been in the game for a few days, players have already found a way to stretch her flying capabilities to new lengths.
Valkyrie's jetpack can be spent in one sustained burst, in short bursts, or in longer bursts, with each providing different advantages, but none of the three makes a big difference in how far she can fly.
On the other hand, if the player holds down Valkyrie's tactical ability as they're flying, they'll be able to fly for nearly twice as long and far as normal. To cancel the tactical, the player must use a melee attack to drop down. This technique allows you to cover more ground, but makes Valkyrie fly more slowly, thereby exposing her to more danger.
Respawn Entertainment has confirmed the technique is intentional and not an exploit, so players are free to use it as they will.