Bypass and TCA

[SSlunt]

We had this come up .

The German squad is using bypass to move through BB4
The Russian tank can see the squad but can it fire at the squad without having to change its TCA or VCA as it bypasses the building in BB4?
Is there any rule example that explicit show or states the answer

Thanks as always

 

[klasmalmstrom]

Hex BB4 is not within the tank's TCA/VCA - so it would need to change CA in order to fire at a unit in BB4.

 

[fanatic+1]

No. D2.321 and example.

 

[Pyth]

Hex BB4 is not within the tank's TCA/VCA - so it would need to change CA in order to fire at a unit in BB4.

Just adding some explanatory commentary to Klas' answer:

Bypassing units are not on a hexside between hexes but in a specific hex. The vertex for a shot against the unit bypassing is also in a hex. That last bit seems confusing but realize you have to assign a range to the shot. To assign a range to a vertex you have to assign the vertex unequivocally to one of the three hexes it joins -- the hex that the bypassing unit is in.

Suppose there were a very small building obstacle in BB5 that made BB5 legally bypassable. Bypass along that hexside but in the BB5 hex would be inside the AFV's TCA and a shot would be range 1. In your example -- same units, same hexside, but different hex being bypassed and now the infantry is outside the TCA and the range 2.

I don't know where the RB explains this in detail, or where a clear example is -- the example at A4.34 doesn't cover this. And the section Ryan cited seems more about the AFV being in bypass than about targetting a unit in bypass, but maybe I missed something.

 

[Binchois]

If you're looking for a rule, remember that a bypassable obstacle and the bypasser still share the same Location (see index and A2.8). After that, it boils down to the basic mechanics of movement and defensive fire.

When a unit expends MF/MP to move (as opposed to performing some action like picking up a weapon or attempting smoke), those points are spent entirely in the hex-to-be-entered (even the first MF had the squad tried to enter the BB4 building). This (BB4) is the hex that lies outside of the AFV's CA.

 

[klasmalmstrom]

Here is the rule:

C.5B FIRE WITHIN CA: A firer that must fire within a given CA must have the hex containing the target completely within its CA—merely having the vertex (or hexside) aiming point forming a part of the boundary of its CA is insufficient.

C.5C The hex containing the target by definition must include the building/woods obstacle being bypassed, or the hex the target would remain in if affected by that fire (e.g., Snapshot [A8.15], Rowhouse “Bypass” [B23.71], Underbelly Hit [D4.3]) or the lower side of a cliff hexside being Climbed (B11.42).

 

[semenza]

D2.321 Change the turret to the bypass side TCA and shoot. Case A and an additional +1. Read D2.321 carefully to see when the extra penalty mod applies.

Note there is only one VCA that a bypass vehicle can have and that can't be changed while in bypass except to move around the hex to the next hexside of the same hex.

Seth

 

[SSlunt]

Thank you everyone - we played it correctly.

 

[Robin Reeve]

Case A and an additional +1. Read D2.321 carefully to see when the extra penalty mod applies.

The T-34 is not in bypass, so the penalty doesn't apply.

 

[fanatic+1]

The T-34 is not in bypass, so the penalty doesn't apply.

Dang! I missed that. I assumed it was. Guess I need my glasses checked.

 

[semenza]

The T-34 is not in bypass, so the penalty doesn't apply.

Ooops, got side tracked on the thinking.

Seth

 

[WWS]

Look at this simply:
Rule A4.34 BYPASS LOS: says Infantry using Bypass are subject to special terrain modifiers and LOS rules. A unit firing at a Bypassing unit does not have to trace its LOS to the target hex center, but has the option to make its one allowed LOS check per attack to either hex vertex along a hexside traversed by a unit moving in Bypass.

Rule C3.2 Covered Arc states, and the Example clearly show that the covered arc (CA) comprises the two hexes joined by that hexspine, all the hexes (and hexsides) of the two diagonal rows of hexes that pass through those hexes while converging on the unit's hex, and all the hexes between those two converging diagonal hexrows.

The unit in the example must traverse the AA5-BB4 hexside, a hexside defined in rule C3.2 as part of the CA.

Hence, it would follow that the tank does NOT have to change its CA to fire at the bypassing unit.


Klasmalmstroms' reference to C.5B and C.5C is interesting but has two confusing aspects
1) C.1-.5 refers to Ordnance so one might say to fire the MA of the tank, you would have to
turn the Turret, but the MG's would be okay to fire without turning. but

2) The reference to Rowhouse "Bypass" [B23.71], would suggest that if the bypass unit was broken it would have to
return to the last occupied location (AA5 in this question) and would therefore meet C.5C

Comments?

 

[Robin Reeve]

Even though LOS is traced to a vertex, the hex which the bypassing unit is in must be in the CA of the firing Gun if the latter wants to fire at it.
A bypassing unit is never straddling a hexside : it always is in one of the hexes separated by that hexside.
So the T-34 must change its TCA to include BB4 to fire with at the unit bypassing BB4.

 

[Ed Caswell]

Look at this simply:
Rule A4.34 BYPASS LOS: says Infantry using Bypass are subject to special terrain modifiers and LOS rules. A unit firing at a Bypassing unit does not have to trace its LOS to the target hex center, but has the option to make its one allowed LOS check per attack to either hex vertex along a hexside traversed by a unit moving in Bypass.

Rule C3.2 Covered Arc states, and the Example clearly show that the covered arc (CA) comprises the two hexes joined by that hexspine, all the hexes (and hexsides) of the two diagonal rows of hexes that pass through those hexes while converging on the unit's hex, and all the hexes between those two converging diagonal hexrows.

The unit in the example must traverse the AA5-BB4 hexside, a hexside defined in rule C3.2 as part of the CA.

Hence, it would follow that the tank does NOT have to change its CA to fire at the bypassing unit.


Klasmalmstroms' reference to C.5B and C.5C is interesting but has two confusing aspects
1) C.1-.5 refers to Ordnance so one might say to fire the MA of the tank, you would have to
turn the Turret, but the MG's would be okay to fire without turning. but

2) The reference to Rowhouse "Bypass" [B23.71], would suggest that if the bypass unit was broken it would have to
return to the last occupied location (AA5 in this question) and would therefore meet C.5C

Comments?

Note that A4.34 also directs the reader to C.5 as well.
Ed

 

[semenza]

Note that A4.34 also directs the reader to C.5 as well.
Ed

Pretty full explanation in C.5 - C.5C

Seth

 

[WWS]

Re-read C.5B and you are correct, The target hex must be completely in the covered arc, so the tank would of had to change its covered Arc.


New Question: If the building in question was a rowhouse then the tank would not have to change its covered arc because as per C.5C (the hex the target would remain in if affected by that fire). and for the rowhouse that hex would be AA5

Am I reading that correctly ??