<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>This article aims to demonstrate through mathematical analysis that the primary reason for the defeat of the Imperial Japanese Navy (IJN) in the battle of the Philippine Sea during World War II (WWII) was quantitative, and that the defeat is particularly attributable to the lack of force concentration. Scholars have placed much emphasis on the qualitative aspects of the forces involved, such as the skill of IJN pilots or the air defence capabilities of the United States Navy (USN), in seeking to explain the Japanese defeat. We, however, assert that in this naval battle, quantitative factors played a more important role than qualitative ones. Accordingly, we offer an improved version of the mathematical model of Armstrong and Powell, which was previously used to analyse battles between aircraft carriers (CVs). The coefficients in our mathematical model will then be estimated and verified using historical data from the main battles between CVs of the IJN and USN during WWII. Finally, we will analyse the factors underlying the IJN’s defeat in the Battle of the Philippine Sea using the model. This study proposes a useful technique for evaluating quantitative and qualitative aspects of naval forces.</p>
</abstract>

This article aims to demonstrate through mathematical analysis that the primary reason for the defeat of the Imperial Japanese Navy (IJN) in the battle of the Philippine Sea during World War II (WWII) was quantitative, and that the defeat is particularly attributable to the lack of force concentration. Scholars have placed much emphasis on the qualitative aspects of the forces involved, such as the skill of IJN pilots or the air defence capabilities of the United States Navy (USN), in seeking to explain the Japanese defeat. We, however, assert that in this naval battle, quantitative factors played a more important role than qualitative ones. Accordingly, we offer an improved version of the mathematical model of Armstrong and Powell, which was previously used to analyse battles between aircraft carriers (CVs). The coefficients in our mathematical model will then be estimated and verified using historical data from the main battles between CVs of the IJN and USN during WWII. Finally, we will analyse the factors underlying the IJN’s defeat in the Battle of the Philippine Sea using the model. This study proposes a useful technique for evaluating quantitative and qualitative aspects of naval forces.

The Imperial Japanese Navy and the battle of the Philippine Sea: An analysis of the main causes of defeat

Journal of Military Studies

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

This article aims to demonstrate through mathematical analysis that the primary reason for the defeat of the Imperial Japanese Navy (IJN) in the battle of the...

IJN forces	1 CV (Hiryu)
USN forces	1 CV (USS Yorktown)
A₂	36
α₂	28
S₂	14
d₂	5

IJN forces	2 CVs (Shokaku and Zuikaku)
USN forces	2 CVs (USS Yorktown and USS Lexington)
A₁	90
α₁	51
S₁	40 (13 fighters and 17 bombers)
d₁	5

	Number of fighters on CAP	Total number of fighters on CVs	Ratio of fighters on CAP to total number on CVs
Battle of the Coral Sea	17	42	0.405
Battle of Midway	14	25	0.560
Battle of the Eastern Solomons	53	100	0.530
Total	84	167	0.503

IJN forces	2.5 CVs (Shokaku, Zuikaku, and Zuiho)
USN forces	2 CV (USS Hornet and USS Enterprise)
A₄	96
S₄	38
d₄	9

IJN forces	2 CVs (Shokaku and Zuikaku)
USN forces	3 CVs (USS Enterprise, USS Saratoga, and USS Wasp)
A₃	90
α₃	54
S₃	53
d₃	3

The Imperial Japanese Navy and the battle of the Philippine Sea: An analysis of the main causes of defeat

Article Category: Original Study

Published Online: Sep 24, 2021

Page range: 154 - 161

Received: Dec 01, 2020

Accepted: Apr 07, 2021

DOI: https://doi.org/10.2478/jms-2021-0006

Keywords
naval tactics, military history, combat modeling, Word War II

© 2021 Yuki Yagi, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Case 2 (Battle of Midway)3

Case 1 (Battle of the Coral Sea)2

Ratio of the number of fighters on CAP to the total number on CVs1

Case 4 (Battle of the Santa Cruz Islands)5

Case 3 (Battle of the Eastern Solomons)4

Case 5 (Battle of the Philippine Sea)6

Case 6 (Battle of the Philippine Sea)7

INJ forces	6 CVs (Shokaku, Zuikaku, Taiho, etc.)
USN forces	11 CVs (USS Hornet, USS Yorktown, USS Wasp etc.)
A₅	270
S₅	236
d₅	0

INJ forces	6 CVs + land-based air force
USN forces	11 CVs
A₆	430 (270 (+ 300(× 2/3 (Defense Agency of Japan, 1971d: 408, 569))
S₆	236

The Imperial Japanese Navy and the battle of the Philippine Sea: An analysis of the main causes of defeat

Article Category: Original Study

Published Online: Sep 24, 2021

Page range: 154 - 161

Received: Dec 01, 2020

Accepted: Apr 07, 2021

DOI: https://doi.org/10.2478/jms-2021-0006

Keywordsnaval tactics, military history, combat modeling, Word War II

© 2021 Yuki Yagi, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Case 2 (Battle of Midway)3

Case 1 (Battle of the Coral Sea)2

Ratio of the number of fighters on CAP to the total number on CVs1

Case 4 (Battle of the Santa Cruz Islands)5

Case 3 (Battle of the Eastern Solomons)4

Case 5 (Battle of the Philippine Sea)6

Case 6 (Battle of the Philippine Sea)7

Keywords
naval tactics, military history, combat modeling, Word War II