Invading in 1.07

[Monarch1st]

Have the invasion rules changed in the new version?
I'm trying to get the islands back from Japan, and am not making much progress.
I've tried invading with infantry, with marines and with tanks and none are able to make much progress if the island is at all defended. 5-1 odds, 15 divs vs 3, are not able to make any progress. I've given them offensive supply. I keep losing org and he loses almost nothing. When I retreat, I've lost 15k men and he's lost three hundred.
Our tech is approx the same. I'm one or so levels ahead of him. He's 47 inf, I'm 51 infantry or m47 patton tank (lvl 7 arm) both with sp rocket arty.
He's does not have any coast forts.
So why can't I win invasions?

 

[unmerged(43138)]

Dont think that much changed in 1.07.

Never use Tanks they have 80 or 90% penalty. Use Marines instead.
Move Capital ships in and set to cost bomb. (Bonus for each capital ship)
If you can bomb the island before with Capital ships/Aircraftcarriers and bombers.
If posible also use Airborn - this is a second level of attack, no big penalty for overstacking.
Check your leader to have at least one general in it. (no over stacking malus)
Also Commando as a leader skill helps. (10% Bonuus)

If you post a attack pic with the details (hoover over the units)than I can give you more help - else good luck.

 

[unmerged(291207)]

In amphibious landing max 3 units can fight effectively. If you go Base Strike naval doctrines path, it's increasing to max 8. And you have landed with 15 units at once. More units is a con in this situation, as stacking penalty has to be taken into consideration too. Try landing with 4 marines at once (you probably have Base Strike doctrine - or more, if you have further doctrines). If you loose, just attack with the next 4 marines immediately.
Of course all bw! advises is also good.

 

[unmerged(286778)]

Amphibious attacks are more complex and different than normal land invasions. Never use motorized, mechanized, HQ, or armour because they cause high penalty. Stacking units also has a high penalty, using marines decrease this penalty. I always use atleast 6 marines in an amphibious attack with a commando cammander trait or offensive, and it also helps when you use naval bombardment. Here read this, its a bit old but it'll help: http://www.paradoxian.org/hoi2wiki/index.php/Amphibious_assault

 

[alufdufe]

Add sparty instead of arty to your marines. It increases their toughness and speed. Use commando leaders on your marines to negate the invasion penalty. Put your marines on offensive supply before loading them in the transports. They'll fight better. Have a second fleet for shore bombardment. 4 shore bombardment factors give a 1% shift to a max of 25%. So the ideal fleet would have 100 factors. The ships in the invasion fleet do not add to shore bombardment. You cannot bomb the island prior to invasion with ships, you have use planes. Use STR on Logistical Strike, and TAC on Interdiction. Against a dug in enemy start at least a month prior to the invasion. Have airfields in the deployment queue ready to place as soon as you have secured the island, so you can rebase your planes to begin working on the next island.

 

[Count of Reval]

Have the invasion rules changed in the new version?
I'm trying to get the islands back from Japan, and am not making much progress.
I've tried invading with infantry, with marines and with tanks and none are able to make much progress if the island is at all defended. 5-1 odds, 15 divs vs 3, are not able to make any progress. I've given them offensive supply. I keep losing org and he loses almost nothing. When I retreat, I've lost 15k men and he's lost three hundred.
Our tech is approx the same. I'm one or so levels ahead of him. He's 47 inf, I'm 51 infantry or m47 patton tank (lvl 7 arm) both with sp rocket arty.
He's does not have any coast forts.
So why can't I win invasions?

I don't know, but it sounds like you might be out of supply.