That was quite a large boat. Sean highly suspected we could still take it out, but was not yet sure if we wanted to. He decided to spend a minute or two on observations, telling everything of note on the radio. Of particular interest:
1. Any signs of whom this boat belongs to? People onboard, mutant air support, flags, whatever...
2. What is the type of the boat and relevant details about it? A TL7/8 cargo vessel? Passenger vessel? A steambot from a museum? Some sort of conversion?
3. Any warlike modifications to it? Armor plating? Gun mounts?
4. Where it seems to be heading? Assuming Sean got to the river wherever it was closest to his original position, the actual pier might be some distance away. Or the boat might head to the far side of the river or something, or be turning right now, for example...
5. What is the terrain at the pier? How much distance those disembarking will have between the boat and the cover? Can we navigate safely hidden somewhere about there, e.g. to plant some radio mines?
6. How wide is the river here? What is the condition of the dam? Is the water up to power plant operation levels or ways down or what? Can the dam be safely crossed out of view of the boat?
7. Not an observation, but just a note: how long it would take us to fold down the nets, start the cars and get lost?
8. Any effect from the rain on these long-distance observations? Expected effect from the rain on long-distance shooting?

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The boat should be ~500 yards away when Sean is done with the first pass of observations. I'm not sure how many rolls would be needed. Sean is in no hurry, so could repeat with more time on any topic(s) he's not immediately sure about. Skill is 15 with an extra +3 to offset range penalties, so the boat itself would be observed at an effective skill of 13 before extra time. Even better about the pier, river and such. People and guns might be problematic if they are not in plain view (an x8 scope means those in plain view should be observed just fine). All of the above is before rain modifiers, whatever they are.