wobbly -> Wobbly's Invasion 101 (8/29/2006 1:12:21 PM)
Conducting an Amphibious Invasion:
An invasion is the most difficult endeavour you will have to conduct within War in the Pacific. So conducting one can be a bit of a juggling act. Many things have to be thought of and confronted. The target should align with your strategic masterplan for the game or at least its phases: as the Japanese you may be looking to secure the Dutch East Indies culminating in the invasion of Java; as the Allies you may be looking to take Majuro with the ultimate task of securing the Caroline Islands.
I have found the following steps a good template for how I conduct my invasions. They are not a sure fire method for success but they seem to have stood me in reasonable stead when conducting them - as always the best laid plans go out the window when the enemy responds and you can often only do as much as he will let you. However, as in most things, having a plan to follow to get to your goal may actually mean you achieve it.
Hopefully these thoughts will help you as well....?
Choose your target to fit with your strategic plan. In a perfect world your target should be:
1. A valid target. By this I mean either a good-sized airfield or port. It should be a part of your greater strategic thinking. There has to be a point in taking it. Don't just take it "cause it's there". There are a plethora of reasons for taking a place, just make sure yours is a good one. Remember, the more attractive the target is to you, the greater the chance the enemy will defend it robustly.
2. Within range of LBA (land based air) and even better within LRCAP of LBA. If not you are very likely to need an Air Combat TF for defensive air cover.
3. Within short range of a friendly base with ample fuel, supplies and air groups ready to move in to the target hex once the base has been taken.
4. Well scouted. You should know how many troops are there and the likely makeup of the troops. Forts - built by local enemy engineers - move combat odds heavily to the benefit of the defender.
In the example given above the Allies have chosen Majuro as a first step in securing the Caroline Islands. This is possibly a poor example as the first consideration in an invasion is "what can the enemy do to counter my move"? With Majuro as a target the answer is: quite a lot unfortunately. It is a valid target as it provides us with a size 4 port - size 4 airfield within the Carolines. However, it is out of any LBA and the closest base you are likely to own is Johnson Island or possible Baker Island; this is a long way for resupply and for damaged ships to get to a safe harbour. Enemy bases also surround Majuro so suppression of aerial counter attacks is going to be very difficult. Therefore this attack is only recommended if you have information that leads you to think the conquest will be VERY rapid and that you can put your own aircraft onto Majuro quickly (so that you don't have to rely upon the air combat groups to provide air cover - they may have their hands full). This leads us to the second point:
Know your enemy! Ahem, well it's true! How many troops will you need to take if you don't know what they're going to face?
There are three legitimate ways to know what you are up against and one that is a bit gamey - your opponent may grump. These ways are:
1. Air Recon - any Bomber or Patrol type plane can do the recon mission but specialist recon planes are the most efficient. Air Recon will give you total number of units and total number of troops (but not type). It can also give you current air power on the island: number of bombers, fighters and auxiliary ACs.
2. Bombing Ground - When a ‘bomb ground’ mission goes ahead you will be told which unit it is targeting. This is a bit unreal but if you keep a note you can get an idea of what's on the ground (bombers will attack the highest assault strength target by default - these are the guys you are worried about anyway so all good).
3. Sigint - Allies only. The allies have very good sigint. Check Sigint each turn and look out for any specifics on your target and keep a note.
4. Commandos - By using a "sub transport" mission you can land a small group of troops on an island. When they attack or are attacked you will get an exact makeup of what is at the target. This is a little gamey and can be frowned upon by an opponent - ask first.
Each of these ways of gathering intelligence has their place. Air Recon and bombing are instant but not terribly informative, it can also act like a finger pointing out your next target to your enemy (therefore it is best to recon multiple targets to at least spread misinformation). Sigint is very detailed but takes a long time to gather. Commando raids should be left to just before the troops land, they are very indicative of an invasion, but they can tell you whether you have bought enough force or not.
Combat troops have the ability to prepare for coming targets. Preparation apparently changes their ability to fight - taken into account in the combat model (although how specifically I don't know). More importantly for amphibious landings, preparation reduces the amount of losses you will take as your troops land. Preparation is a long-range inclusion to the equation though is it takes 100 days before your units are fully prepared. You may not have the luxury of this time, considering that your ambitions are likely to change due to other pressures in the theatre.
Recognise your support base/s and stock them well with fuel, supply and ACs (of all types). Move AR, AD and AS ships to the support base. The ARs especially can be the difference between a ship sinking or being saved. If the base is within range, having a Cavalry, Raider, SNLF or other small unit (without vehicles or heavy weapons) and transport planes, can allow you to bolster the number of defenders if the enemy heavily counterattacks.
In order to take bases you must take combat ground troops. These come in a range of different guises but as a rule of thumb, for every regiment of infantry on the target you should bring a division for the invasion. I treat armour units, artillery and small combat units as extras it gets too complicated otherwise. The other two important additions to an invasion are HQs and Combat Engineers. An army HQ (don't make the mistake of bringing a Naval or Air HQ) can add 10% to your assault prowess. Combat Engineers are even more important. They increase your chances of bringing down the forts you are sure to face. While the enemy has forts up you are going to struggle to take his base!
Base Engineers, Construction Engineers, Air and Naval HQs, CD units and to a lesser extent AAA units should be bought in after the base has been captured. Bring them in within an Auxiliary Transport TF (see Extra Fleet requirements). These guys will repair and make useful your hard gotten gains.
Task Forces (TFs) required:
An Amphibious Invasion, by definition, requires attack from the sea. You therefore have to carry everything you need to the target hex via ship (OK I know you could use air transport but lets not get too pedantic here). You must assess within your planning and preparation the number and size of the task Forces you will need to take your target. I have split the task forces required into Essential and Extra Fleet requirements (obviously this is opinion - do with it as you will).
Essential Fleet requirements:
1. Invasion TF- Use LSTs/LSDs, then APs, and at a pinch AKs. Include MSWs, DDs and a couple of CLs or CAs and later as allies LST(G)s (MSWs will help sweep any mines, DDs are there for ASW work, counter-battery of shore-guns and anti-air, the Cruisers are counter-battery and Anti-air). The warships also tend to attract aircraft attacking the taskforce - better them than your loaded transports!
Also consider adding CVEs - these will provide air cover for the TF, and they can have a small amount of offensive capability as well. They don't appear to suffer from lack of sea room for launching Aircraft like the CVs do in an air combat Task Force.
Each ground unit you are trying to take has a lift rating (how much capacity it requires to be carried), try to allow an extra 50% carrying capability over the total amount of troops you are carrying, i.e total troops require 30,000 capacity, make your TF about 45,000. APs, LSTs and AKs all load and unload units at different speeds. When you combine these different ships into the same invasion TF it can be very difficult to prophesise the amount of carrying capability you will need. It is easier to create multiple TFs, each made of the same type of hull, allocate one unit to each and then combine the lot once they are loaded. Of all units’ armour and artillery units are slightly different in that they load faster upon AKs than APs or LSTs.
Another important consideration is how the ships will unload at the invasion hex. It is far better to use LSTs and small APs, in large numbers, than try and cram your troops into as small a number of ships as possible. The reason is that at the other end they will disembark far more rapidly if every ship is disgorging at the same time, the LSTs and APs are also faster at unloading than the AKs. You want speed of unloading as the men are better off on land (than in the ships), and if you are invading an atoll (any piece of land, with a base, that occupies only one map hex: Kwajalein is an atoll - Fiji is not) your troops are forced to shock attack the turn they land. If the shock attack is unsuccessful it can shatter your land units, greatly increasing the time needed to capture the target base.
2. Supply TF- Use AKs, MSWs and PGs. AKs are the best ships for carrying supplies. Again the rule of thumb is: the more ships in the TF the better. 10 AKs unloading supplies will get more on the beach in a turn than 5. You have to make a judgement call upon what quantity of supplies you will require to subdue the defending garrison. You will also need supplies to repair damage to the base, fly any missions from the base once repaired, and allow engineers to start to build fortifications or enhance the base size.
3. Surface Combat TF- Use CAs, CLs, DDs possibly BBs (depending on what opposition you think you might meet, enemy BBs for instance). Primary role is defending the invasion TF. These ships can provide ASW, Anti-Air and interdiction of enemy surface combat TFs. Make sure they have ‘follow orders’ of the invasion TF.
4. Auxiliary Forces TF- Use AKs, PGs, MSWs . The Auxiliary Forces TF carries non-combatant units: Base engineers, Construction Engineers, Air and Sea HQs - basically any unit that is superfluous to the requirement of actually taking the base. I find it better to separate these guys so that they don't suffer the disruption and damage involved with landing while the enemy holds the base and the beaches. Better to wait and unload these guys once the base is secured. This way they land without being damaged and the full force of their repair capabilities etc can be bought online.
Extra Fleet requirements depending on size of invasion:
1. Air Combat - Use CVs, CVLs, CAs, CLAAs, DDs and mayby fast BBs. It must have enough airpower to cover itself, LRCAP the landing zone (you do not want the air combat TF in the landing zone - it suffers "cramped condition take off" penalties in the confines of the invasion hex) and escort bombers against enemy TFs or against ground troops in the invasion hex. If you have enough ships I recommend two Air Combat TFs splitting the fleet and light carriers between them (don’t' use CVEs, they will reduce the Task Force's speed).
It is often beneficial to have the Air Combat TFs follow a dedicated Surface combat or ASW TF. You can give the Air Combat TFs follow orders (of the attached surface combat group) and then just move the surface combat group around - the Air Combat groups will follow. The surface combat group can also become the target of an incoming air raid (rather than the precious flat tops).
2. Mine Sweeping TF - Use MSWs, DMSs (allied only) and possibly PGs or DDs. Minesweeping is vital against Human players. All of us appear to love mines. Although you can add MSWs to other TF types, they are more efficient in a purpose-built minesweeping TF. Minesweeping TFs should follow the invasion TF. Caution, adding PGs and DDs to a minesweeping TF is for defence against enemy surface groups, however, while MSWs and DMS' are immune to mines these escort ships are not and may hit a mine while the TF performs its duty.
3. Bombardment TFs - Use Fast BBs, BBs, CAs, CLs and DDs. Bombardments of the target hex are not a necessity but are to be highly recommended. An intact CD unit at an invasion hex can ruin your whole day - damaging transport ships, counter-battery warships and killing the troops as they try to come ashore.
Bombardment TFs can smash the port and landing ground defences of a target hex. They are also very good at smashing the facilities and aircraft located at the airfield of the base hex.
Bombardments are usually a one shot weapon; after ammo is expended any further attempts to bombard with the same TF will result in markedly reduced results. Having a friendly base with supplies (ammo) and fuel nearby can allow you to re-arm your bombardment mission - think about this during your planning stage. Because bombardment missions are one-shot weapons, and because enemy engineers will start to repair damage done to facilities, it is often prudent to bring extra bombardment TFs and stagger their use. Hopefully by the time the last Bombardment TF has expended itself the first has arrived back on the scene having re-armed at your re-supply base.
Be very careful with using the "escorts bombard" setting. Your DDs are not very resistant to shore based fire and you can have a massacre on your hands very quickly.
4. ASW TF - Use DDs, PGs, MSWs and DEs (allies only). Dedicated ASW TFs give you the best chance of catching up with enemy subs snooping around your operations. The optimum number of escorts is about 6. Any more than this and not all escorts take part in an ASW attack.
It is a good idea to have two ASW TFs in your invasion armada, one to escort your main carrier TFs and one to escort the invasion TF.
5. Sub Patrol TF - Subs are very useful during and before an invasion for scouting the likely approach tracks of the enemy. Line subs up in the direction you think the enemy is going to approach from. The enemy is almost guaranteed to have either cruiser, BB, or carrier based planes searching. When these spot your sub the sub will notify you that it has been overflown. Such information can be the difference between being prepared and being surprised. Japanese Glen Subs, with their small search plane, are especially capable at this job - use these guys well - they are gold!
6. Replenishment TF - Use AOs, CVEs, TKs, Escorts. The Warships, especially the escorts, do not have large fuel bunkers (the Japanese suffer more from this - their ships were conceived as local defence, not a Pacific wide force). Therefore they often need replenishment at sea. While the escorts can replenish from the Capital ships, the Capital ships can only replenish from a base or replenishment TF. A replenishment force can provide mid-ocean refuelling. AOs are the most efficient at this. A refuelling ship will replenish ships up to the remaining operational points it has (1000 is the total daily allotment). So in order to refuel a large number of ships you will have to provide more AOs.
The US Navy also has CVEs like the Nassau and Altamaha within their inventory. These ships can replace destroyed ACs on CVs and CVLs (from planes in their hold). Air Combat TFs can suffer massive losses to their air wings, being able to replenish them while at sea can be a godsend.
7. Mine Laying TF - Use MLs and DMs. A minelaying TF is a luxury, but it can be a boon if the enemy makes a very strong riposte to your invasion attempt. Once the base is taken (this is very important - do not lay mines until you own the base or your ships will hit them as well) order the minelaying TF to lay their mines in the new base hex.
Be very careful with the orders you give to a minelaying TF. Give them "Patrol do not retire" orders until you are ready to lay the mines (then change to "retirement allowed" with a waypoint of the invasion hex). Otherwise your Minelaying TF can lay its mines uselessly at sea and even worse your TFs can sail into your own mines - grrrr!
Tactics – the Invasion
There is no way I can create a ‘for all situations’ blueprint for an invasion as just the addition of a second base within range – say of Baker Island upon an invasion of Canton Island – complicates the situation by an order of magnitude from attacking an isolated base like Wake Island. There are however a few dos and don’ts that I try and follow.
1. Set all TFs to have a home base of your support base/s where you have stashed your ARs, busted ships will head here after being damaged and the few hexes spent gallivanting off in the wrong direction could be their loss.
2. Try to keep your Task forces together as much as possible. This way they all benefit from mutual protection – most specifically from any fighters in attendance. The easiest way to do this is to make sure all others follow the slowest TF. In practise this can be difficult as ASW TFs (or others of low endurance) refuel from replenishment TFs. This uses their operation points and they don’t travel as far as they should that turn.
3. The turn before the invasion forces get 9 hexes out set up any LBA (that can reach) to hit the airfield. Any dent to the local air capacity is a good thing. If you have been bombing the target for a while then this shouldn’t ring too many alarm bells.
4. About 9 hexes out from the target gather all your TFs together again. Organise sub-based commandos to unload on this turn. If there are far more troops here than you thought contemplate a postponement or cancellation.
5. 5 hexes is a good kick off point as a surface or bombardment group, in one high speed run into the target, can usually cover it. Send in the first Bombardment group and a surface combat group if you are expecting a reception committee.
6. Most invasion TFs move 4 hexes in a turn. So they will be 1 hex from the target in the next turn. This means that on D-Day they will have the longest period, with the largest contingent of operation points allocated to unloading the troops. If it is an atoll you are invading you are going to be forced to shock attack and you want to give yourself the best opportunity of doing this with the most men. From hex one you also want to send in another bombardment group if available.
7. Any Air Combat TFs can go wherever you like but don’t move them over a base location – they will have their AC launch capacity severely curtailed. Set up a sizable number of fighters to LRCAP the invasion forces, be careful not to neglect your Air Combat TF – it is the juiciest target in the area and is likely to grab the most attention. I like to move my Air Combat TF around a little – especially if I think bombardment TFs have done their job on the target well. This can allow me to sneak up on enemy Surface Combat or Air Combat TFs getting in position to race in on the following turn. Better to hit them away from the invasion. Contemplate turning some of your carrier planes to ‘bomb ground’ orders – the disruption the meet out to the infantry might just be enough to tip the balance.
From here hopefully you get a good attack that reduces forts or, if extremely lucky, takes the base. If not you are in for a hard slog. Choices like: do I get more men, what is the enemy going to start to do about this, am I better off evacuating. All of these will depend on the situation you find yourself.
Be wary of diversions and remember that the goal here is to take the base; once taken it is beneficial to get the Auxiliaries in and get a few forts up before building the airfield and port up. Move your land based ACs up to the new base.
Anyway – no doubt there are plenty of folk out there that know more about specific bits and pieces and also have a different way of doing things. This is my way – you are welcome to add you thoughts.