Sunday, December 16, 2018

A River Runs Through It... Twilight: 2000 Amphibious Start

In the original "Escape from Kalisz" scenario, there is an explicit setup meant to drive the characters in a southwards direction (towards Krakow and/or Silesia) due to the initial placement of the Soviet forces and the natural geographic features eg the unfordable Warta River. This post explores an option of a more northerly route, extrapolating on the potential if the characters start with or readily acquire an amphibious vehicle or vehicles.


Northern Kalisz Escape Route map circa 20th July 2000 (spoilers)

So let's imagine the characters start with just a M113 tracked APC. Probably an M113A3 to be exact (T2k v2.2, page 74). In the woods to the northeast of Kalisz, south of the Turek-Uniejow road and east of the Warta as shown in the above map.

Compare to a group travelling with a mixture of a couple of HumVees, motorcycles, and/or a few trucks (eg "deuce-and-a-half" and/or a 5-ton truck/tanker) perhaps converted into "gun trucks" this opens up an interesting option of (albeit somewhat limited) amphibious capability, and it's the river crossing capability that allows for the potential of a different departure route for an Escape from Kalisz campaign...

1) Northeast, straight towards Warsaw in fact via Kutno then Lowice, bypassing Krakow and the Vistula completely for a segway directly into the Ruins of Warsaw supplement arriving in the west near the road through the suburbs Srodmiescle, Mirow and Mokotow. 
2) West or Northwest, either along the Warta westwards directly to the Oder or else northwards following the canal near Konin that leads to the Notec via the Bydoszcz (Bromberg) lock complex and then again onwards to the Oder and the more friendly territory of Germany... (see Going Home for useful details).

A campaign involving a fully amphibious movement capable party ie. *all* vehicles (or a solo vehicle without trucks or a trailer) capable of crossing or traveling along stretches of rivers would therefore be different to a group with a wheeled LAV-25 and a Hum Vee, like the iconic T2k v1.0 group used for play examples in the original boxed set.

Note: this post uses some variant from canon details drawn from Paul Mulcahy's "Tracked APCs - US" page. Unless otherwise noted however I refer to the "base" vehicles from the core book or the American Combat Vehicle Handbook (page 22 for the M113, page 26 for the LAV-25) .

Why an M113, not just a LAV-25?


Mainly because I like the idea of a variation to the example group and using the M113 - it's always been and will likely remain such an iconic vehicle from its inception and in widespread use in its many variants and upgrades. The image below shows a later modification circa ~1999 which enables "sea to shore" capability that may not have come into production in the Twilight World:

M113A3 "AmphGavin" fitted with "AAV-like" nose for sea to shore travel


Superficially, the LAV-25 wheeled infantry fighting vehicle occupies a similar starting vehicle "slot" (accessible only to a party of 4 or more on a roll of "10" on 2D6 as opposed to a "11" on 2D6) and has similar capabilities - it's amphibious, similar Weight (11 or 12 tonnes), has slightly better Fuel Consumption (base 90 vs 120), and has a faster Combat Move and a better road Travel Move than the tracked APC whereas their off-road Travel Move 85 is actually equivalent. The M113 has full radiological shielding and headlights instead of just the enclosed status and passive IR of the LAV-25.

Both vehicles have the same Load (2 tonnes, but an extra 10% strapped to the outside as both armoured), and reasonable armour protection although the LAV-25 is slightly less protected than the M113. Given a medium still weighs 2 tonnes, for independent travel ie. not needing a support vehicle mounted still / tanker such as perhaps the M-548 below, either vehicle sacrifices their whole internal carrying capacity.

Unfortunately there don't appear to be any real amphibious US or NATO trailers apart from the small 340kg capacity M-100 jeep trailer from Paul Mulcahy's website, but I'm unsure whether this could be adapted to be towed in water as both the APC and the wheeled IFV sit very low in the water anyway. Any trailer cargo would have to be shifted to the outside of the armoured vehicle for a river crossing and the trailer abandoned.

Designed for carrying a troop complement, each option has enough space to carry a small beginning party - the LAV-25 can carry a total of 9 characters, but needs a crew of 3 compared to an M113 ability to transport 11 characters beyond the base crew of driver and commander. That's 4 extra characters for an M113 equipped group, which I think is a significant positive - the M113 really is an APC and it shows in this capacity for a starting campaign, readily allowing for dependents and non-combatants.

Sure, if you're looking for firepower the LAV-25 carries a 25mm autocannon in a turret used on the Bradley (as does the Dutch/Belgium AIFV variant of the M113 or the improved M115A1 AACV) with Fire Control +1 and Basic stabilization (no penalty while moving at normal speed), but it has only a lighter co-axial MAG MG.  The basic M113 variants lacks this autocannon, but has the advantage of the heavier 2HB MG on the M113 that can be readily dismounted onto a NHT and is unlikely to run into ammunition issues (the LAV-25 has a base of only 630 rounds for it's 25mm, after which it's main gun is useless unless this uncommon NATO round can be bought or scrounged in useful quantities. Tanks in the starting scenario are rare and best avoided or dealt with by anti-tank missiles IMO, so I feel that while the autocannon may be an early advantage or deterrent, it's role reduces or expires as the campaign progresses.

The M113 does lack the (6) firing ports of the LAV-25, but it has not only rear access but also top deck access for all the passengers with 2 additional heavy weapons mounts (and capacity to jury-rig more with the right tools and character Assets). This allows the APC to work more like a tracked "gun truck" ("gun track"?) rather than just a "battle taxi" as while the gunners are less protected, for combats with lighter "soft-skinned" vehicles or troops, the whole passenger troop can contribute if the rear deck doors are opened. The ACAV style modifications from the Vietnam era and/or applique armour kit (see Paul's website for suggested details) add to the survivability, as does the AACV option (American Combat Vehicle Handbook, page 23). To me this is more in keeping with my concept of vehicle use and travel in a beginning Poland campaign - patched up and field modified older equipment desperately maintained.

In the late 1960s, a waterjet propulsion system was developed for amphibious operations. This allowed the M-113A1 on which it was tested to roughly double its swimming speed and greatly increase waterborne mobility. The waterjets were steered by vanes. Air was sucked in from the top of the waterjet modules and pushed out under the water level to form the jets. Ballast was added in the front to ensure stability. The waterjet system was, however, decided against by the Army. In game terms, adding a waterjet propulsion system adds 300 kg to the weight of the vehicle (which is subtracted from the M-113s cargo capacity) and adds $4000 to the cost of the vehicle. 
- Paul Mulcahy's Twilight 2000 website

M-548 as 5-ton "truck" variant amphibious support option

Similar in concept to the M113 (and cheaper at around $50,000 base cost depending on whether using an official source (American Combat Vehicle Handbook, page 10) or the "Heavy Unarmoured Vehicle" section of Paul's website) is the M-548 "heavy track" 5-ton amphibious cargo carrier:


Even if not rolled as an option (equivalent to a 5-ton truck, ie a roll of an "8" or "9" on 2D6) it's low price makes it readily accessible as a secondary starting amphibious cargo vehicle (particularly if reduced by accepting a Wear value of 2 or more ie. only $25,000 or even less, potentially affordable by a starting group of 4+ characters). 

It's main drawcard is it's considerable cargo capacity of 6 tons - easily enough to accomodate a medium still (2 tonnes) for itself and the M113, with perhaps a 1000L tank to accomodate spare fuel supplies and enough room left over for other equipment. Offset against this is that while it has comparable base Fuel Consumption (140 vs 120)  it is somewhat slower than the M113 (off-road travel only 70), "soft-skinned" (unarmoured), somewhat unreliably amphibious, and has no significant radiological shielding or passive IR capability. It does come with the same M2HB machinegun on a ring mount shared with it's M113 cousin however, allowing for consolidation of ammunition supplies with the APC.

Optionally, at the loss of the reliability of amphibious capability (reflected by the need for a Skill check to not founder when used at a river), it could be upgraded into a solo "gun track" similar to the base conversions of the "deuce-and-a-half" and 5-ton "gun trucks" from Challenge Magazine #55 (pages 6-8). This "gun track" field improvisation adds steel plate armor (equivalent to HF / HS / HR: 4 level) and at least 2 additional weapons mounts, but at the cost of dropping the speed and decreasing the available Load to only 4 tons. For a smaller group interested more in gear than personnel, this less glamorous option could be an interesting variant starting vehicle option.

A Marines Variant?


Rather than a M113A3 (or modified "gun track" M-548), a group somehow linked to the Marines or with a few Marine characters may choose to use a so-called "Amtrac" AAVP7A1 or variant instead - a roughly equivalent in price and capability APC exclusive to their armed forces branch with an increased personnel carrying capacity, load and some sea-going capability, shown here cruising down a river:

AAVP9 Tracked Amphibious Vehicle crossing a river

AAVP9: The AAVP9 is an advanced version of the AAVP7A1 amphibious armoured personnel carrier, entering service in the early 1990's. A 40mm AGL and M2HB MG combination is mounted in a small cupola on the right front hull deck, and there are two smaller hatches for the driver and vehicle commander on the left front hull deck. The rear deck contains two large doors for disembarking personnel, and the rear has a ramp/door which can be lowered as well. The vehicle is fully amphibious. The 40mm AGL is identical in performance and characteristics to the Mark 19.
Price: $80,000 (R/R) RF + 15 Armament: 40mm AGL, M2HB MG Ammo: 350 x 40mm Tr Move: 120/70 Com Move: 40/30 Fuel Cap: 360 Fuel Cons: 120 Fuel Type: D, A Load: 4 tons Veh Wt: 18 tons Crew: 2 + 22 Mnt: 6; page 30 US Army Vehicle Guide (v1.0) or page 25 American Combat Vehicle Guide (v2.2).
As you can see from the above, the "Amtrac" is all around better armed and armoured, reliably amphibious with some sea-going capacity, has more crew protection for it's crew operated weapons and has a bigger cargo capacity, overcoming most of the limitations of the M113A3 for a similar core rules cost. Although slightly slower it has not only greater personnel capacity (a commander and an extra 11 characters beyond the M113) but also the advantage of carrying not only a medium still but also a remaining 2 tonnes of internal cargo and 1800kg of external cargo strapped to the outside.

To me the "Amtrac" has a big personality - it's rare in Poland and distinctively American, can operate independently and I think has the potential to become almost a separate "vehicle character" in it's own right or legend in itself amongst the remaining Soviet forces in the area. Discreet? Not so much - it's very uniqueness makes it stand out and marks it as a potential trophy to enemies.

Explaining Marine character(s) presence and such a signature vehicle with the remnants of the US 5th Division forces in central Poland may require some back-story explanation but given the chaotic nature of the later stages of the Twilight War and the tendency for remnants of disrupted units to be incorporated into remaining units, it's a plausible beginning single vehicle option if somewhat higher powered.


Rules References


Addit: Wayne suggested the following relevant amphibious vehicle references from the v2.2 rules:

  • Page 213: Movement
  • Page 214: Swamping
  • Page 220: Penetration

"A referee that wants to allow amphibs, but not be used immediately in Escape From Kalisz, can add a few hull penetrations along with the Wear roll. The PCs could patch their amphib up later, but are quite busy at the moment."



3 comments:

  1. The amtrac is the size of a bus though. In Iraq they were very vulnerable to the type of combat we're postulating in T2k

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  2. Yes the Amtrac is comparatively large and likely suffers for it in the T2k context.

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  3. I'm a big fan of the AAV in T2k but as everyone says it's an RPG magnet.
    But it really should be just a protected truck and not a battlewagon. Use its armour to defend against artillery fragments and nothing else. It certainly shouldn't be leading the convoy with its big profile.

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