Wooded Streams and LOS Across Them.

Tim Niesen

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JR, What that I am saying is if a unit is in Crest status on one side of a woods-stream hex, would not the woods on the other side of the woods-stream hex at Crest level block LOS to the other unprotected side of the Crest entrenchment? Tim
 

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JR, I understand that a Unit in a Crest entrenchment does not have TEM or protection from FFMO if an entry unit fires down that stream. Although does this not differ if the unit is in Crest status along and down a number of woods-stream hexes downstream. Tim
 

Brian W

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JR, What that I am saying is if a unit is in Crest status on one side of a woods-stream hex, would not the woods on the other side of the woods-stream hex at Crest level block LOS to the other unprotected side of the Crest entrenchment? Tim
No. You are subdividing a single location and trying to draw a different LOS to within that location. That does sometimes happen in ASL, but it is rare (bypass LOS), and this is not one of those cases. Your Crest unit could get TEM from the woods or from the Crest status, or no TEM at all depending on the firing unit's LOS.

I find that many people forget about Crest status not when seeking the TEM, but when planning moving the next turn--being at crest can save 1-3mf for infantry leaving the depression.
 

jrv

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JR, I understand that a Unit in a Crest entrenchment does not have TEM or protection from FFMO if an entry unit fires down that stream. Although does this not differ if the unit is in Crest status along and down a number of woods-stream hexes downstream.
Elevation can also negate the crest TEM. A unit adjacent to the depression at crest level always has LOS INTO the stream and so does not use the crest TEM. Likewise a unit at range one at elevation one sees INTO the stream and does not use the crest TEM.

JR
 

Tim Niesen

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I can see where Crest status helps in the exit from a depression. Even though getting out of the entrenchment costs a movement point, the hex entered does not double in cost. Tim
 

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I can see where Crest status helps in the exit from a depression. Even though getting out of the entrenchment costs a movement point, the hex entered does not double in cost.
One of the more common uses for crest status is to avoid Advance vs. Difficult Terrain when advancing out of a depression hex into woods, building, brush or other two MF terrain. If you start IN the depression the cost of entering these terrain types will be four MF (double of two MF for going up a level), which will be Advance vs. Difficult Terrain. If you can end up in crest at the end of the MPh, the cost to enter the next hex will be three MF (one MF to exit foxhole and two MF to enter the terrain), avoiding Advance vs. Difficult Terrain (unless inexperienced, carrying extra PP, wounded SMC, etc.).

JR
 

Tim Niesen

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I am still not sure I completely understand LOS and woods-stream hexes. Other than what Brian explained. If point A is on one side of a woods stream hex, and point B is on the other side of the same woods stream hex. Point A cannot see point B. Yet somehow Point A can see the Crest area on the other Crest side of the intervening woods stream hex. I can see how that ATT could shoot from point A to the whole steam woods hex. But I would think that direct fire from point A to the opposite Crest side of the intervening stream woods hex would be akin to firing at a concealed or HIP target. But my understanding of ASL physics is limited. Tim
 

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Think of it this way with hexes A, B (woods-stream) and C in a row. You fire from A. You can fire at anything in B, but the woods bit in B stops fire from any fire affecting C.

There are a few cases where you could not fire at an adjacent hex, like firing from a Pillbox through the NCA, but as a general rule firing at an adjacent hex is always allowed. The thing about a unit being in Crest on the opposite bank is that it still is in hex B. It in real life might be closer to C than A within the B hex, but it still is in B.

If B was simple woods then anywhere in B is vulnerable to A but anything in C is not. Think of the B-C side as a magical barrier to A's fire. Now let B be woods-stream again. The only difference in real life is that there is some "open ground" in the form of the stream. Indeed A would be "shooting them in the back" if it fired on a unit on a Crest at the B-C side.

So you have A, A-B hexside, possible Crest at A-B side, IN stream, unit in Crest at B-C side, B-C hexside and finally C. IE the Crest status is before the magical B-C hexside barrier.
 

jrv

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I am still not sure I completely understand LOS and woods-stream hexes. Other than what Brian explained. If point A is on one side of a woods stream hex, and point B is on the other side of the same woods stream hex. Point A cannot see point B. Yet somehow Point A can see the Crest area on the other Crest side of the intervening woods stream hex. I can see how that ATT could shoot from point A to the whole steam woods hex. But I would think that direct fire from point A to the opposite Crest side of the intervening stream woods hex would be akin to firing at a concealed or HIP target. But my understanding of ASL physics is limited. Tim
First when you shoot at a non-stream woods hex, which side of that hex is the target really on? Perhaps they are on "this" side of the woods, but perhaps they are on the "other" side from the firer. ASL makes that all abstract; you have LOS to every part of the hex (ignoring bypass around an obstacle). If you can see through a "solid" woods hex, you should be able to see through a "hollow" woods hex that has a stream through it.

Second although the ASL artwork makes it look as though there are dozens of trees from one side of a woods hex to another, in fact the scale of the map is 40m per hex. How many trees is that? Just as a rough number say that trees are roughly 20 feet (20 times 1⁄3 of a meter) apart. That means you look past roughly six trees to go from one edge of a solid woods hex to the other. With a stream, say 5-10m across, in the middle it's even fewer. Of course there will be some underbrush too, but it's actually a little surprising that you can't see farther into at least some woods (and in Korea light woods are +2 hindrances rather than obstacles).

But all of this is post hoc justification (reality argument) of the rules. The rules say that the terrain in a hex does not block LOS to any non-bypass part of that hex. So although it looks to you like your LOS crosses the hex to what seems to be indicated on the crest counter as the bypass part of the hex, the rules do not consider the unit to be the same as a unit in bypass, and in fact LOS is still traced to the hex center. So by rule there is LOS despite the fact that the target is on the "other" side of woods.

JR
 

Tim Niesen

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In our campaign game the terrain has a stream lying Adjacent with a long hedge across my line of advance. Will I get the Crest TEM plus the Hedge TEM if shot at from across the favorable Crest hex-sides? I assume that I can fire across the half level Hedge from my Crest entrenchment at same ground level. Or is my LOS blocked except for shooting at level 1 terrain on the other side of the Hedge? How would this affect Wall Advantage. Perhaps I cannot claim wall advantage while in a Crest position Adjacent to a Hedge or Wall. Tim
 

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Will I get the Crest TEM plus the Hedge TEM if shot at from across the favorable Crest hex-sides?
No. Entrenchment TEM cannot be combined with wall/hedge TEM.
I assume that I can fire across the half level Hedge from my Crest entrenchment at same ground level. Or is my LOS blocked except for shooting at level 1 terrain on the other side of the Hedge?
Your LOS is limited just as if you were in a foxhole behind a wall. However, you can still see units at a higher elevation (some of which may be able to see INTO the depression and thus negate TEM from Crest).
How would this affect Wall Advantage. Perhaps I cannot claim wall advantage while in a Crest position Adjacent to a Hedge or Wall. Tim
Units in an Entrenchment cannot claim WA. However, I don't see an exception in B9.32 for a unit in Crest status, though. I'm probably missing something, as I cannot believe a unit in Crest could claim WA. As messy as the WA rules are though, maybe they can.
 

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Brian. Thanks. I was thinking that the Crest entrenchment was different from a foxhole relative to a Wall or a hedge, but you clarified the situation. Tim
 

Tim Niesen

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But the negation of the entrenchment benefits TEM of Crest is limited to nearby units which can directly see into the stream bed. Right? In this case of an enemy mortar shooting through the Crest hex sides from twenty plus hexes away from a two level spotter there is still the benefit of the Crest TEM on the result of the ATT hit. Right? Likewise, the Hedge Adjacent to the stream hex from which the Crest hexes are placed does not block LOS from a third level observer regardless of distance. Right? Tim
 

Tim Niesen

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I understand that the TEM only affects the results of the ATT hit. Sorry to imply otherwise.
 

Tim Niesen

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These observations seem obvious. But I just wanted to clarify any distinctions between Crest status and a foxhole. In many ways there are the same. At least from a LOS point of view. Both are blocked by a half level obstruction unless firing or being fired upon by a unit not at a higher level. Tim
 

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But the negation of the entrenchment benefits TEM of Crest is limited to nearby units which can directly see into the stream bed. Right?
Right.
In this case of an enemy mortar shooting through the Crest hex sides from twenty plus hexes away from a two level spotter there is still the benefit of the Crest TEM on the result of the ATT hit. Right?
Crest status, unlike a real entrenchment, does not provide TEM for Indirect Fire (on-board Mortars and OBA). But, if in your example the weapon was a ART gun using the ATT firing from level two 20 hexes away, then yes, the unit in Crest would receive the TEM.
Likewise, the Hedge Adjacent to the stream hex from which the Crest hexes are placed does not block LOS from a third level observer regardless of distance. Right? Tim
Exactly. Units at higher elevation see past hedges regardless of range, even if they cannot see INTO the depression.

EDIT: Note that a hedge never blocks LOS into its hex, only beyond that hex. The "exception" in this case is the Entrenchment LOS rule, which limits same level LOS to adjacent hexes when a unit is entrenched.
 
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Tim Niesen

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Brian, I was unaware of the exception of Adjacent units for Entrenchments for same level. I was thinking that it only occurred when one side was claiming wall advantage. Tim
 

Brian W

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Brian, I was unaware of the exception of Adjacent units for Entrenchments for same level. I was thinking that it only occurred when one side was claiming wall advantage. Tim
The LOS rule for Entrenched units behind Walls/Hedges is B9.21.

Note that the only time WA affects LOS (that I can think of right now) is when Bocage (B9.5) is in effect.

I recommend new players avoid Bocage scenarios until they are very comfortable with the WA rules. After 25 years of ASL, I am still not comfortable with WA and wish they would be simplified to the point where WA only applied to Bocage scenarios. They are far too much work for the questionable payoff in a game the scale of ASL. JMO, which will change nothing so nod in sympathy and then forget it.
 
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