Flight Beacons

See the data pack in action on Youtube.

This data pack brings flight, similar to creative flight, into survival Minecraft. The Flight Beacon gives flight to players within a 32 block radius of it. Moving horizontally enables a Levitation status effect to keep the player airborne at the same height, with movement aided by the Speed status effect. Vertical movement is enabled by stopping still, at which point a Shulker will be summoned below the player for them to stand on, and the Levitation effect is removed. Crouching on the Shulker will cause it to teleport downwards 1 block, and jumping will bring it upwards with you.

To activate and deactivate a Flight Beacon, deal between 0 and 5 damage to it (0 to 2.5 hearts). Flight Beacons have a slow regeneration effect, so they'll recover from activation and deactivation. Dealing enough damage quickly will break a Flight Beacon, causing the item used to place it to drop so it can be placed again.

Once the players goes beyond the area of effect of the Flight Beacon, its effects will wear off, and the player is given 30 seconds of Slow Falling. The same thing happens to flying players if the last Flight Beacon they're in range of is deactivated.

As for Version 7, Flight Beacons can be created by renaming a Chorus Flower in an Anvil to "Flight Beacon". Prior to Version 7, Flight Beacons had a chance to drop from Shulkers.

If you wish to test this data pack out in creative before deciding to add it to your world, you can give yourself a flight beacon with the command "/function flight_b:give_beacon". Please note that you will then need to switch your gamemode to survival for an activated flight beacon to effect you correctly.

More information about data packs and how to use them can be found on the official Minecraft Wiki.