The cooldown for mortars/arty is faster than the time it takes for for mortars/arty to even start being bombarded on the map.

If you call in a mortar/arty and wait for the cooldown to call it in again, you will be able to then call in a second mortar/arty barrage before your last firesupport even starts being bombarded on the map.

The time it takes for fire support to arrive on the map is too long.
Most of the time it will end up killing your teammates instead of supporting them because it comes too late.

Arty and mortar are not bad in pvp, but there are no points to use them in coop, the most useful thing is helicopters and bomb drone.
Compare to Day of Infamy, they indeed need a time buff.

Yeah I don't know why they made it slower, was fine before.

I'd be willing to bet it's because they made the mortars physically visible from launch time to the time they arrive. (although it often bugs out and you can't see them coming for me) If you look into the sky you can see rockets and mortars as they fall. They would need to somehow speed up the entire visual, rather than just arbitrarily reducing "arrival time".

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