Factors in Amphibious Landings

[Hano]

I'm doing some island hopping and was trying to come up with a formula that works having been bloodily repulsed from some islands, as far as I can see the key factors are:

Have an Amhibious Force HQ in an AGC with the force
Ensure that your assault elements are in vessels that can unload them straight onto the beaches AP, APA, AKA, LST not XAP or AK
Add Combat Engineers into the mix with your assault wave
Do your prep in terms of planning - setting the island as a future objective and allowing the preperation to get to 100%
Ensure the units are rested and fully up to strength with an "Assault" leader.

How important in WIP terms are:

Aircraft flying Ground Attack?
Preparatory Bombardment by CA-BB?
Experience?

Are there other factors that I'm missing?

[GetAssista]

ORIGINAL: Hano
How important in WIP terms are:

Aircraft flying Ground Attack?
Preparatory Bombardment by CA-BB?
Experience?

Are there other factors that I'm missing?

Quantity matters. If you can afford to bomb and bombard for weeks before you actually land, it will erode supply (best case scenario - to zero) and disable/destroy quite some devices. Alternatively, if you can do a massive bombing/bombardment the day before attack it will run up enemy units' disruption which decreases their effectiveness (a lot if disruption is high). But don't rely much on the latter, do some Head-to-head to get a feel of how things are. Cracking fortified atolls is a long game if you don't want massive casualties.

Experience is always good

Bring tanks

[Hano]

Thanks for that... I had a few rude shocks, I hadnt really considered tanks but thats good advice.

I normally try to get inf & CE ashore, then bring in more inf, HQ & Arty in second wave, but I've had my first wave almost wiped out a couple of times.

Good point about disruption factor of bombardment/bombing I was purely looking at it from a killing the enemy point of view rather than disrupting him.

[Uncivil Engineer]

ORIGINAL: Hano

I'm doing some island hopping and was trying to come up with a formula that works having been bloodily repulsed from some islands, as far as I can see the key factors are:

Have an Amhibious Force HQ in an AGC with the force
Ensure that your assault elements are in vessels that can unload them straight onto the beaches AP, APA, AKA, LST not XAP or AK
Add Combat Engineers into the mix with your assault wave
Do your prep in terms of planning - setting the island as a future objective and allowing the preperation to get to 100%
Ensure the units are rested and fully up to strength with an "Assault" leader.

How important in WIP terms are:

Aircraft flying Ground Attack?
Preparatory Bombardment by CA-BB?
Experience?

Are there other factors that I'm missing?

I would also have artillery and tanks in the first wave AND ships loaded ONLY with supply which will unload with the first assault troops. Otherwise, supply unloads last, which is not good. Air supremacy (or at least air superiority) is desirable; you want his planes on the ground and not attacking your amphib TF. Several days of bombardment by battleships is a good idea, but then surprise is not possible.

[Hano]

Thanks folks, I really appreciate this, I will re-run my last disasterous attack but bring in what we have talked about and see how it comes out.

Cheers

H

[GetAssista]

Ah, one more. A very important factor is to embed BB/CA caliber ships in an amphibious force itself. They suppress shore batteries and draw fire to themselves in the landing phase. And they are much more effective than bombardment TFs at hitting enemy land units, so if you lack ships and have to choose between bombardment and embedding - choose the latter. Other combat ships are ok to embed too, but they run higher risk of being seriously damaged by shore guns

[RangerJoe]

If you have a base within range, put a Command HQ there with it preparing for the target. Load as much of a unit per ship as the ship can unload in one day, no multiple days of unloading the same unit if you can do it in one day.

[CV10]

Pre-invasion bombardment is crucial for atoll invasions. The damage and disruption they cause for the defender can make all the difference in the world for the attack force.

I play as the Allies and my preference is for a a few bombardment TFs with a pair of old BBs each.

Embedded CAs and BBs in the amphibious group are also critical, particularly if the target has a lot of artillery defending it. As others said, they draw enemy fire away from your troop transports and landing craft.

[Macclan5]

ORIGINAL: Hano

I'm doing some island hopping and was trying to come up with a formula that works having been bloodily repulsed from some islands, as far as I can see the key factors are:

Have an Amhibious Force HQ in an AGC with the force
Ensure that your assault elements are in vessels that can unload them straight onto the beaches AP, APA, AKA, LST not XAP or AK
Add Combat Engineers into the mix with your assault wave
Do your prep in terms of planning - setting the island as a future objective and allowing the preperation to get to 100%
Ensure the units are rested and fully up to strength with an "Assault" leader.

How important in WIP terms are:

Aircraft flying Ground Attack?
Preparatory Bombardment by CA-BB?
Experience?

Very good post and welcome to the learning curve.

As you progress you will also find that the enemy ( The Japanese ) plays defense stronger and stronger. Each base will have (perhaps) more coastal artillery, higher defensive fortification, etc etc

If i.e. Tarawa comes of good... Guam is harder ... and Iwo Jima is a B%^&* [8D]

1) Recon Recon and then when you have Reconed enough - 3 more turns with good experienced Recon Pilots

2) Sub patrol interdiction all around the base. Try to ensure the AI is not sneaking in 'fast supply missions' or even more troops in there.

3) If you can - if you have established bases in close proximity - Shore and Air Bombard the target base. Reduce Port / Reduce Air field. Make the enemy base burn up supply repairing damage for multiple turns / days / weeks and even months.

This is ironically somewhat easier in later war when you are well progressed and will have multiple bases to support i.e. the Mariana's to support target Iwo Jima or the Philippine's to support target Okinawa. Ironically it is often the early invasions that are somewhat tough as you may not have a well developed base with tons of supply / fuel / AE's in ports nearby.

Its a long way from Wake or Entiwok to Guam for example

4) Minesweep Minesweep Minesweep the target

(Bombard Bombard Bombard as well to cause disruption of the enemy with the landing)

5) Advice above.

Tanks / Defensive Battalions / Artillery in early with the Infantry.

Yes Combat Engineers are critical

Yes 100% Prep and Unit experience is very important to minimize the loss / disablement of your troops.

Consider ENG units with Naval Support for unloading

Consider supply ships ladden nearby ready to unload

Consider an Air Transport Mission nearby ready to unload some local CAP as soon as you have the airfield

Congrats and welcome to the 'learning curve'

[BBfanboy]

ORIGINAL: Hano

Thanks for that... I had a few rude shocks, I hadnt really considered tanks but thats good advice.

I normally try to get inf & CE ashore, then bring in more inf, HQ & Arty in second wave, but I've had my first wave almost wiped out a couple of times.

Good point about disruption factor of bombardment/bombing I was purely looking at it from a killing the enemy point of view rather than disrupting him.

This is a good time to mention the progression of damage to enemy units. Unless you have overwhelming power to destroy the enemy in one combat, the longer term grind looks like this:

- first, combat will cause fatigue and perhaps morale drop in the enemy unit
- next, fatigue and loss of a few men within each squad will cause disruption numbers to climb, possibly decreasing morale some more
- next, loss of more men or wounding of some will result in disablement of some devices. These devices can be restored after some rest and replenishment, if the unit is allowed time with no combat
- next, at about 50% disablements for all the devices in the slot, further combat tends to destroy more and more of the squads/devices.
- finally, when almost all the devices are disabled the unit as a whole is ripe for destruction. Smaller units tend to reach this point much sooner than larger units.

The progression above emphasizes how important it is to keep pressure on once you attack the enemy, so that they do not recover too much. Sustained bombardment of the enemy from air, sea and land arty is recommended if your own troops need to rest for a while. You can even consider swapping out your heavily disrupted units for fresh ones to limit your own losses while keeping pressure on. Use of APDs and other fast loading/unloading vessels is recommended for this. You can leave heavy equipment ashore until you bring back the rest of the unit or withdraw the equipment after you defeat the enemy. Equipment does not enter into the stacking limit of the Atoll.

[HansBolter]

All ship types capable of being included in an Amphibious TF and capable of carrying land units unload over the beaches.

Unloading over the beaches is not a function special to certain types of ships.

APs, AKs, APAs and AKAs all have heavily increased unload rates over the beaches compared to xAPs and xAKs.

That is why they are the preferred types for invasions where rapid unloading is required.

Beaching craft unload everything in a single phase, making them highly desirable for invasions where rapid unloading is desirable.

xAPs and xAKs are perfectly fine for invasions where rapid unloading is not a factor.


Morale, Fatigue and Disruption are the Triumvirate of land combat. The effects of attacks on these factors are never reported to the player, but are extremely important. Multidimensional attacks that will suppress Morale and increase Fatigue and Disruption are ALWAYS key to the success of any land combat, including invasions.

[Ian R]

No one has mentioned collecting everything in a hex a adjacent to the target, and then going in and unloading from 1 hex away, so that you get two unload phases before the shock attack.

Ideally you organise something like this to form up one hex away -

1) your lead TF that everyone follows is your AGC carrying the prepped Amph force HQ, set to not unload.

2) Your bombardment SAG.

3) Your CVE TF(s).

4) Your assault landing TF. Note regarding the escorts taking shore fire - Fletchers are good in this role because they have some armor plate.

5) A separate supply force made up of combat loaded AKs.

6) A support force with AR, AE/AKE, AD, and AOs, that can anchor in the atoll as soon as it's secured and get to work.

7) A replenishment TF to service, at least, the CVEs.

8) An empty TF AP/AK that arrives empty and is tasked with lifting your marines straight off the atoll and heading back to pearl for R&R.

9) Your garrison and engineers/base force TF which will unload after the atoll is secured.

The turn you issue the order 'land the landing force', you can manually set the orders for the assault TFs to make sure they do what they are supposed to.

Things the jury is still out on -

- Loading a corps HQ in your landing force, prepped for the target;

- Loading a command HQ into an amph TF (set to not unload) and taking it with you, so that it is in command range, and in combat mode*.

(* Try this experiment: If you have a unit somewhere that is due for a TOE upgrade but is out of range of a command HQ (e.g. the Samoan Marine battalion is good for this), load a 9 range command HQ in combat mode on an amph TF and move it to a point within 18 hexes of the unit (set to rest/upgrade), to see if it triggers the TOE upgrade. The result with respect to that command function may not mirror the result with respect to another, different function.)

[RangerJoe]

Actually, you should have at least ASW TF lead the way, possibly followed up with a minesweeping TF with ASW capability. Don't forget IJN minisubs.

[Ian R]

ORIGINAL: RangerJoe

Actually, you should have at least ASW TF lead the way, possibly followed up with a minesweeping TF with ASW capability. Don't forget IJN minisubs.

Agree, but didn't you send the DMS TF in weeks ago before you started the caricole of bombardment TFs?

[RangerJoe]

ORIGINAL: Ian R

ORIGINAL: RangerJoe

Actually, you should have at least ASW TF lead the way, possibly followed up with a minesweeping TF with ASW capability. Don't forget IJN minisubs.

Agree, but didn't you send the DMS TF in weeks ago before you started the caricole of bombardment TFs?

You should or at least embed some minesweepers with the bombardment forces but more minefields could be laid.

[Hano]

Thanks for the pointers, I thought I had taken everything onboard and was landing at Iwo Jima in Aug 44 with 5+ divisions of marines, CE, Tanks, Arty and all of that good stuff.

All my troops landed from AKA, APA or LST with a few other flavours of LSD etc, but not all got onto the beach on the first day, I had done a preparatory bombardment by five BB, this is what happened:

Ground combat at Iwo-jima (108,77)

Japanese Bombardment attack

Attacking force 46916 troops, 594 guns, 171 vehicles, Assault Value = 1611

Defending force 63607 troops, 1422 guns, 1444 vehicles, Assault Value = 2842

Japanese ground losses:
5094 casualties reported
Squads: 266 destroyed, 16 disabled
Non Combat: 121 destroyed, 6 disabled
Engineers: 0 destroyed, 0 disabled
Guns lost 71 (67 destroyed, 4 disabled)
Vehicles lost 11 (11 destroyed, 0 disabled)
Units destroyed 1

Allied ground losses:
588 casualties reported
Squads: 29 destroyed, 36 disabled
Non Combat: 4 destroyed, 6 disabled
Engineers: 3 destroyed, 4 disabled
Guns lost 36 (15 destroyed, 21 disabled)
Vehicles lost 2 (2 destroyed, 0 disabled)

Assaulting units:
12th Ind.Mixed Regiment
42nd Naval Guard Unit
54th Naval Guard Unit
50th Ind.Mixed Brigade
23rd Division
6th Garrison Unit
109th Division
13th Ind.Mixed Regiment
11th Ind.Mixed Regiment
Iwo-jima Naval Guard Unit
10th RF Gun Battalion
100th Ind.Hvy.Art Battalion
9th RF Gun Battalion
4th Ind.Hvy.Art. Battalion
31st Army
12th Naval Construction Battalion
152nd AA Regiment
11th RF Gun Battalion
22nd JAAF AF Bn

Defending units:
1st Marine Division
3rd USMC Tank Battalion
29th Marine Rgt /1
5th USMC Tank Battalion
131st Combat Engineer Regiment
102nd Combat Engineer Regiment
1st USMC Amphb Tank Battalion
3rd Marine Div /1
4th Marine Div /1
2nd Marine Division
2nd USMC Tank Bn /44
22nd Marine Regiment
2nd USMC Amphb Tank Battalion
5th Marine Div /32
11th USMC Field Artillery Battalion
8th USMC Field Artillery Battalion
1st USMC Field Artillery Battalion
9th USMC Field Artillery Battalion
2nd USMC Field Artillery Battalion
7th USMC Field Artillery Battalion
USMC AirFMFPac /1
12th USMC Field Artillery Battalion
10th USMC Field Artillery Battalion
4th USMC Field Artillery Battalion
III US Amphib Corps /1


--------------------------------------------------------------------------------

Ground combat at Iwo-jima (108,77)

Allied Shock attack

Attacking force 62173 troops, 1411 guns, 1442 vehicles, Assault Value = 2776

Defending force 45828 troops, 610 guns, 204 vehicles, Assault Value = 1402

Allied adjusted assault: 1

Japanese adjusted defense: 3481

Allied assault odds: 1 to 3481 (fort level 6)

Combat modifiers
Defender: terrain(+), forts(+), experience(-)
Attacker: shock(+)

Japanese ground losses:
505 casualties reported
Squads: 31 destroyed, 0 disabled
Non Combat: 57 destroyed, 12 disabled
Engineers: 0 destroyed, 0 disabled
Guns lost 12 (7 destroyed, 5 disabled)
Vehicles lost 157 (157 destroyed, 0 disabled)

Allied ground losses:
26501 casualties reported
Squads: 2060 destroyed, 200 disabled
Non Combat: 753 destroyed, 331 disabled
Engineers: 564 destroyed, 25 disabled
Guns lost 1090 (954 destroyed, 136 disabled)
Vehicles lost 857 (808 destroyed, 49 disabled)
Units destroyed 7

Assaulting units:
4th Marine Div /1
131st Combat Engineer Regiment
2nd USMC Amphb Tank Battalion
3rd USMC Tank Battalion
5th USMC Tank Battalion
3rd Marine Div /1
2nd Marine Division
22nd Marine Regiment
1st Marine Division
1st USMC Amphb Tank Battalion
2nd USMC Tank Bn /44
29th Marine Rgt /1
102nd Combat Engineer Regiment
5th Marine Div /32
1st USMC Field Artillery Battalion
7th USMC Field Artillery Battalion
8th USMC Field Artillery Battalion
9th USMC Field Artillery Battalion
4th USMC Field Artillery Battalion
10th USMC Field Artillery Battalion
11th USMC Field Artillery Battalion
USMC AirFMFPac /1
2nd USMC Field Artillery Battalion
12th USMC Field Artillery Battalion
III US Amphib Corps /1

Defending units:
54th Naval Guard Unit
11th Ind.Mixed Regiment
109th Division
23rd Division
42nd Naval Guard Unit
50th Ind.Mixed Brigade
13th Ind.Mixed Regiment
6th Garrison Unit
Iwo-jima Naval Guard Unit
4th Ind.Hvy.Art. Battalion
152nd AA Regiment
9th RF Gun Battalion
11th RF Gun Battalion
100th Ind.Hvy.Art Battalion
10th RF Gun Battalion
12th Naval Construction Battalion
31st Army
22nd JAAF AF Bn

Next turn one of my marine divisions surrendered.... what went wrong????

[LargeSlowTarget]

1. More pre-invasion recon
2. After #1 discovered how heavily defended Iwo is, change your strategy and bypass the island
3. However, if you really want it, keep it isolated and bombard and bomb it for weeks / months with everything including the kitchen sink - until lack of enemy AA fire indicates that the defenders are out of supplies - you want a "Combat modifiers Defender: supplies (-)"
4. Then land and bring all available combat engineers to tackle the forts and LOTS of supplies - like hundreds of thousands of tons - esp. if the landing force is overstacking Iwo Jima
5. Don't forget to sacrifice a virgin the day before the landing

[Alfred]

The Combat Report shows a poor invasion set up.

You won't get any more useful answers without providing screenshots of all the TFs involved, LCUs involved, and detection levels.

Nor does it seem you degraded the defenders before landing.

Alfred

[Nomad]

To be honest, I don't think even screenshots will be enough. You will have to send your game files( the before the landing and the one of the landing ) to someone to analyze. That is probably the only way you will get a complete answer.

[BBfanboy]

Part of the issue is that you have way overstacked the island. Stock Scenario 1 gives a stacking limit of 30,000. You can overstack at a cost in supplies, and I think some cost in casualties. Players who have overstacked to take Atolls report that over 2X the stacking limit supply usage goes very high and combat rolls suffer.

Better to bring more firepower in terms of tanks and arty (which you had lots of) rather than masses of infantry. If you can hold off the initial attack by your troops (if the island is not an atoll) and just bombard for a few turns with your artillery that will help.

Best solution is to grind the defenders and their supply down for a while. It took me over six months of bombing and bombardment to grind Truk supply and defences down to 0.