Higher ground has no advantage and its actually disadvantage?

[Ramibuk]

So i put a machine gunner at second floor in a barn as it should be great spot for defending.He saw alien behind bush wall but when i tried to shoot him but it says 100% block,so i thought i will wait a turn and then shoot trough it with a few bursts.So you can imagined how suprised it was when alien start shooting without penalty(hit with all bullets(RIP)) through it and killed my guy.Bush wasnt damaged.It looked like this: (x mean nothing)

Alien,x,x,x,bush fence,x,x,cover,barn(Soldier on second floor)

Another weird thing is shooting while hiding behind corner,alien is shooting right into my soldier but i got 100% block to shoot back...

A,W,W,W,W,x,x,x,x,x,x,x

x,x,x,x,x,x,x,x,x,x,x,x,x

x,x,x,x,x,x,x,W,W,W,W,S

[aplomado]

Cover right next to an individual doesn't block that individual's shooting (simulating shooting a gun over/through cover I guess).

[ViewThePhenom]

Allows you to shoot over cover.

Grants sight range increase.

You don't have any defensive bonuses, so don't leave your units out of cover on rooftops.

[Ramibuk]

Point is that bush has 100% block from my position,but alien can shoot trough it.And he isn't behind it but 3 or 4 squares behind.My soldiers can never shoot through bush walls,they must destroy it first.I should take screenshoot ,but i rage quit.

[Ramibuk]

Allows you to shoot over cover.

Well as I said in first post its not true.Alien down at ground can shoot over it,soldier upstairs cant.

EDIT also i send another soldier upstairs,but he still get 100% block...

[vaultdweller]

You can shoot over cover from higher ground in some cases, but the effect is not as pronounced as it often looks like it should be. All actors and props fill the volume of their tiles (vertically and horizontally), regardless of how they are drawn - whether it's a tall wall or a log on the ground, it still occupies the full volume of that tile. Moving to higher ground will let you shoot over cover if the trajectory for the projectile can reach the target without passing through the covering tile ('cube' would be a better term than 'tile' really).

In your case, the higher ground wasn't high enough to shoot over the wall, but it didn't put you at a disadvantage, either. The alien didn't shoot over the cover, it shot around it. It would have been able to hit you at ground level, too. The trajectory for shooting around cover seems unintuitive to some. I believe the path of the projectile is calculated from the best possible corner of the shooter's tile, to the center of the target's tile. This means that a shooter can often shoot around the corner of cover, and be completely protected from return fire.

[Hathur]

Elevation isn't quite as advantageous as one might expect, but it is still considerably helpful.

Using either buzzard armour or sentinel armour, I find it a must to have a scout with a sniper rifle use high ground as often as possible. It provides significant extended sightlines and most of the time (but not always) makes it easier to hit a target. Far more often than not I am able to shoot over or ignore cover that an alien has vs were I on the ground directly below (particularly helpful on urban maps. Fly on top of a building and fairly safely pick off aliens that are on the other side of a high wall. Works quite well most of the time.

At the very least, it provides a safer method of performing recon or getting line of sight on an enemy for your snipers at the rear lines.

[BuzuBuzu]

I agree that firing mechanics from elevated positions are not very intuitive, and from my experience parking someone on a roof very often turns into a turkey shoot for the aliens. Shooting at ground level means you often have a clutter of objects to shoot over, but when you're elevated it usually means there's at most one piece of cover between you and a clear shot.

However the real value of elevated positions in my opinion is that they you see far more of the map and enemies than from ground level (although in most instances it's very unrealistic, like being on a southern edge of a building roof and being able to see every single thing below the northern edge of the same building). This really lets you increase your situational awareness and Buzzard armor is in my opinion the single coolest item in terms of gameplay in the game.

Like others have said already, if you do leave someone in an elevated position, make sure they're crouched behind at least one piece of cover or not within sight of aliens.