Forward Observer
Defaults: IQ-5, Artillery (any)-5, and others.
This is the skill of being a "spotter" for artillery. It includes locating targets (with map and compass at TL6-, global positioning systems and satellite imagery at TL7+), marking targets (using smoke, a laser designator, etc.), matching ordnance to target for best effect, and calling in corrections to any fire you personally observe.
Failure means the ordnance misses the target; critical failures result in severe "collateral damage" or "friendly fire" incidents. The very worst critical failures (GM's decision) drop the ordnance on your position!
At higher tech levels, Forward Observer is less about observing targets and more about operating specialized technology such as drones, GPS, and laser designators. To remotely pilot a drone or use a laser designator to direct "smart" munitions onto a target, make a DX-based skill roll. At TL7+, Forward Observer defaults to Electronics Operation (any)-5.
Modifiers: Equipment modifiers; -2 if you are unfamiliar with the artillery (e.g., aircraft bombs when you are used to naval guns); -3 per 500 yards between you and the target – but divide the actual range by the magnification of any vision aid first.