Flying-type Pokemon and their moves are more situational compared to other moves, which says a lot in a glorified rock-paper-scissors style of gameplay.
While there are some exceptions, such as Yveltal's Oblivion Wing or Lugia's Aeroblast, most Flying-type moves don't hit much without some type of drawback. The merits of using Flying-type moves, however, comes from their utility.
Note: This article is subjective and reflects the opinion of the writer.
What are the top 5 Flying moves in Pokemon?
#5 - Fly
This is an honorary placement more than anything. Fast travel is a feature unlocked by players in more recent games. Before Generation VII, getting the Fly HM was one of the most freeing and glorious moments of the game.
Unlike most other HMs, Fly was a useful move in battle. With a base power of 90 and the fact that it can receive STAB (Same Type Attack Bonus), Fly hit pretty hard. While taking an extra turn to attack was annoyingly slow, it could be used strategically to avoid dangerous attacks like a charged-up Bide or Solar Beam.
#4 - Brave Bird
Brave Bird is one of two de facto moves to go for if the player wants pure power in a Flying-type move. The other is Hurricane. However, since Hurricane requires a rain team to work effectively (or just one really good Pelipper), Brave Bird takes this spot on the list instead.
With a power of 120 and 100% accuracy, Brave Bird is basically guaranteed to cripple the opponent. However, there is a major downside as the player takes severe recoil damage. This isn't a move that you can use to sweep a party with unless you stop for a Roost midway through.
#3 - Roost
Roost is an exceedingly useful move that restores half of the user's HP. This is great for both tanky Pokemon that want to stall out their opponents and for Brave Bird users that need a little pick-me-up in the middle of their one-hit KO sweep.
In addition to restoring HP, Roost removes the user's Flying-typing (if it has one to begin with). While this makes the user no longer immune to Ground-type moves, it also removes the Pokemon's weakness to Electric, Ice and Rock-type moves. On top of that, if a pure Flying-type Pokemon Roosts, they become Normal type. Under the right circumstances, this could be used to completely dodge dangerous Ghost-type moves.
#2 - Aerial Ace
Aerial Ace is not particularly powerful as it only has 60 base power. Despite this, however, it is an exceedingly useful move during regular gameplay.
Normally obnoxious threats like a Double-Team spammer or a Pokemon with Sand Veil are easily dealt with via Aerial Ace. One of the best things about Aerial Ace is the fact that many Pokemon can learn it. Aerial Ace is one of those TMs that you boot up out of curiosity to then find that most of your team can learn it.
With so many Pokemon having access to this useful evasion counter, Aerial Ace has more than earned its place on this list.
#1 - Defog
Defog is a move that is often overlooked by casual players. Having said that, all of Defogs primary uses are much more prominent in competitive play, so it can't really be helped. It also doesn't help that it's a forced HM in Generation IV, or that the in-game description for Defog so criminally underexplains the extent of its capabilities.
This utility move, as explained in the games, lowers an opponent's evasiveness and clears barriers such as Reflect and Light Screen. This alone makes it decent since it can deal with Double-Team spammers and defensive set-ups.
However, what the games don't tell you is that Defog also clears the opponent's hazards, such as Spikes, Toxic Spikes and Stealth Rock. On top of that, as of Generation VIII, it also clears opponent-created terrains.
Admittedly, these effects aren't as useful in a casual playthrough. However, Defog's overwhelming usefulness on the competitive stage, as well as its usefulness in dealing with annoying evasiveness Pokemon in casual play, makes it well-deserving of this first-place spot.