unit counter: Akagi

An Ideal Pearl Harbor

(Even more odds for VitP)

By Bill Burch

unit counter: Hornet

Sunk Damaged Disabled

Introduction

Let me state this clearly at the beginning. There is no ideal Pearl Harbor raid. There are only methods to maximize attaining your objectives. Most commonly we see the IJN player with eight carriers attacking the eleven targets (2 cruisers, 8 battleships, and the LBA) in Pearl Harbor. So what are the possible goals of the IJN player attacking Pearl Harbor? Does he want to maximize damage, maximize kills, or maybe maximize bottoming ships? Does he want to eliminate the 7th AF? Though there are more tactical approaches than I have alluded to here, these are the most common questions regarding a Pearl Harbor raid and they'll be the tactics I'll address.

Maximum Damage

Maximizing damage is the easiest tactic to address. The guidelines for maximizing damage to the enemy fleet shows that we need to: (1) airstrike the maximum number of enemy targets, (2) arrange airstrikes from the largest AF to the smallest, and (3) use the airstrikes in the order of 4+, 3+ then 2+. Hence the four 4+ airstrikes are targeted on the West Virginia, Maryland, California, and Tennessee. While the two 3+ and the two 2+ airstrikes are targeted on the Nevada, Arizona, Oklahoma, and Pennsylvania. This airstrike arrangement gives the greatest amount of damage to the US Fleet at an expected value of 30.56 damage. Different combinations can be checked out by using the table below to find their expected damage.

Maximum Damage Table
Target
Attacker 1-1-7 4-4-3 X-5-3 7th AF
4+ 2.20 4.32 4.52 1.67
3+ 1.88 3.36 3.46 1.33
2+ 1.44 2.30 2.33 0.94

Maximum Sinkings

Maximizing sinkings and the following maximum bottomings are harder tactics to address. The guidelines for maximizing kills to the enemy fleet shows that we need to: (1) attempt to airstrike the maximum number of enemy targets, and (2) arrange airstrikes from the smallest AF to the largest. By checking the most likely combinations to yield the best kill results I found a not so obvious answer. Two 4+ airstrikes target the two 1-1-7 cruisers followed by three 6+ (2x [4+,2+] and 1x [3+,3+]) airstrikes targeting three of the 4-4-3 battleships. This airstrike arrangement gives the greatest amount of kills to the US Fleet at an expected value of 2.726 kills. Some of the different combinations can be checked out by using the table below to find their expected number of kills, but the table does not show the expected kills when airstrikes are combined. It is also necessary to remember when engaging targets in Pearl Harbor (port) that the effective AF is doubled for ships. Hence a 4-4-3 battleship has an effective AF of 8, while the X-5-3s have an effective AF of 10. The 7th AF, not being a ship in port, does not double its AF and retains its effective AF of 3.

Maximum Sinking Table
Target
Attacker 1-1-7 4-4-3 X-5-3 7th AF
4+ .663 .167 .084 .315
3+ .549 .089 .037 .242
2+ .404 .031 .009 .164

Maximum Bottomings

The guidelines for maximizing bottomed ships are the same as sinking the enemy fleet and shows that we need to: (1) attempt to airstrike the maximum number of enemy targets, and (2) arrange airstrikes from the smallest AF to the largest. By checking the most likely combinations to yield the best bottoming results I found two fairly obvious answers. If you include the 7th AF in the target list (some won't when trying to bottom ships), the largest expected number of bottomed ships is 3.530. For this raid, two 3+ airstrikes target the two 1-1-7 cruisers followed by the four 4+ airstrikes targeting the four 4-4-3 battleships while one 2+ airstrike targets the 7th AF and the other 2+ airstrike targets a 5-5-3 battleship. If you don't include the 7th AF as a target then both 2+ airstrikes will target the two 5-5-3 battleships and will lower the expected number of bottomed ships to 3.520. Some of the different combinations can be checked out by using the table below to find their expected number of bottomed ships, but the table does not show the expected bottomings when airstrikes are combined. It should be noted that most results that include the two 1-1-7 cruisers and a one-on-one targeting matchup will get high results fairly close to the maximum number.

Maximum Bottoming Table
Target
Attacker 1-1-7 4-4-3 X-5-3 7th AF
4+ .737 .488 .386 .315
3+ .630 .370 .270 .242
2+ .481 .241 .154 .164

Killing the 7th Airforce

Trying different strategies in Victory in the Pacific sometimes requires the elimination of both the 5th and 7th AF LBA units. But in two of the three raids described above the 7th AF isn't engaged in the first round. In the remaining raid, the 7th AF is targeted by a lone CVL(2+) with a lowly 16.4% of eliminating the LBA unit. A LBA unit requires 7 airstrike factors to have at least a 50% chance of elimination and it requires 13 airstrike factors to exceed 75% chance of elimination. Using 13 airstrike factors against the 7th AF is excessive, but using 7 factors (over possibly two turns) to attempt to eliminate the LBA (> 75% chance) is acceptable and may be combined with the bottoming method to produce acceptable results without sacrificing too many airstrikes. The best possible results can be obtained by using a 4+ and a 3+ targeting the 7th AF, a 4+ against a 1-1-7 cruiser, a 3+ against the other 1-1-7 cruiser, two 4+ airstrikes against two 4-4-3 battleships, and the two 2+ airstrikes against the final two 4-4-3 battleships. This raid results in a 50.6% chance of eliminating the 7th AF along with an expected value of 2.825 bottomed ships (3.331 overall).

Second Round

So after covering the above first round of the raid and maximizing the airstrikes, what do you do? Easy, use the same principles to conduct the second round as you used in the first. You want maximum damage, target the biggest remaining AF first. To sink ships, target the smallest first and double up (using about 6 airstrike factors) to attack larger targets. If you want to bottom the most ships, target the smallest remaining AFs first and don't double up until all targets have an assigned attacker. Using these simple methods will always help you get the most out of your raids. Good Luck!

- wcmb