[Salmo]

i know what he means, the time delay is only good for 10 seconds. mine ordnance should be able to have delays of hours

Maybe not hours, but in the context of a 1 hour mission, say a delay of 1 - 20 minutes.

Mines - Should be proximity activated ie. go off when a moving object is close or hit the spot.

Time-fused ordinance - (1) time delay say 1-20 minutes to explode.
(2) multiple small ordinance with random time delay say 1-20 minutes. This was actually used in WW2 to drop on airfields so the enemy was kept busy trying to clear the airfield of bombs and aircraft could not land or takeoff because they never new when a bomb on the runway would go off.