[Sidebar (page 34):]Marine Tanks at OkinawaTheSherman M-4 medium tank employed by the seven Army and Marine Corps tank battalions on Okinawa would prove to be a decisive weapon—but only when closely coordinated with accompanying infantry. The Japanese intended to separate the two components by fire and audacity. “The enemy’s strength lies in his tanks,” declared Lieutenant General Mitsuru Ushijima before the invasion. Anti-tank training received the highest priority within hisThirty-second Army. These urgent preparations proved successful on 19 April when the Japanese knocked out 22 of 30 Sherman tanks of the 27th Division, many by suicide demolitionists.The Marines fared better in this regard, having learned in earlier campaigns to integrate infantry and artillery as a close, protective overwatch to their accompanying tanks, keeping the “human bullet” suicide squads at bay. Although enemy guns and mines took their toll of the Shermans, only a single Marine tank sustained damage from a Japanese suicide foray.Lieutenant Colonel Arthur J. Stuart commanded the 1st Tank Battalion during the Okinawa campaign. The unit had fought with distinction at Peleliu a half-year earlier, despite shipping shortfalls which kept a third of its tanks out of the fight. Stuart insisted on retaining the battalion’s older M-4A2 Shermans because he believed the twin General Motors diesel engines were safer in combat. General del Valle agreed: “The tanks were not so easily set on fire and blown up under enemy fire.”By contrast, Lieutenant Colonel Robert L. Denig’s 6th Tank Battalion preferred the newer M-4A3 model Shermans. Denig’s tankers liked the greater horsepower provided by the water-cooled Ford V-8 engine and considered the reversion to gasoline from diesel an acceptable risk. The 6th Tank Battalion would face its greatest challenge against Admiral Minoru Ota’s mines and naval guns on Oroku Peninsula.The Sherman tank, much maligned in the European theater for its shortcomings against the heavier German Tigers, seemed ideal for island fighting in the Pacific. By Okinawa, however, the Sherman’s limitations became evident. The 75mm gun proved too light against some of Ushijima’s fortifications; on these occasions the new M-7 self-propelled 105mm gun worked better. And the Sherman was never known for its armor protection. At 33 tons, its strength lay more in mobility and reliability. But as Japanese antitank weapons and mines reached the height of lethality at Okinawa, the Sherman’s thin-skinned weak points (1.5-inch armor on the sides and rear, for example) became a cause for concern. Marine tank crews had resorted to sheathing the sides of their vehicles with lumber as a foil to hand-lobbed Japanese magnetic mines as early as the Marshalls campaign. By the time of Okinawa, Marine Shermans were festooned with spot-welded track blocks, wire mesh, sandbags, and clusters of large nails—all designed to enhance armor protection.Department of Defense Photo (USMC) 123166Both tank battalions fielded Shermans configured with dozer blades, invaluable assets in the cave fighting to come, but—surprisingly—neither outfit deployed with flame tanks. Despite rave reports of the success of the USN Mark I turret-mounted flame system installed in eight Shermans in the battle of Iwo Jima, there would be no massive retrofit program for the Okinawa-bound Marine tank units. Instead, all flame tanks on Okinawa were provided courtesy of the U.S. Army’s 713th Armored Flamethrower Battalion. Company B of that unit supported the IIIAC with brand-new H-1 flame tanks. Each carried 290 gallons of napalm-thickened fuel, good for two-and-a-half minutes of flame at ranges out to 80 yards. The Marines received consistently outstanding support from this Army company throughout the battle.The Marines employed the newly developed T-6 “Tank Flotation Devices” to get the initial assault waves of Shermans ashore on L-Day. The T-6 featured a series of flotation tanks welded all around the hull, a provisional steering device making use of the tracks, and electric bilge pumps. Once ashore, the crew hoped to jettison the ungainly rig with built-in explosive charges, a scary proposition.The invasion landing on 1 April for the 1st Tank Battalion was truly “April Fool’s Day.” The captain of an LST carrying six Shermans equipped with the T-6 launched the vehicles an hour late and 10 miles at sea. It took this irate contingent five hours to reach the beach, losing two vehicles on the reef at ebb tide. Most of Colonel Stuart’s other Shermans made it ashore before noon, but some of his reserves could not cross the reef for 48 hours. The 6th Tank Battalion had better luck. Their LST skippers launched the T-6 tanks on time and in close. Two tanks were lost—one sank when its main engine failed, another broke a track and veered into an unseen hole—but the other Shermans surged ashore, detonated their float tanks successfully, and were ready to roll by H plus 29.Japanese gunners and mine warfare experts knocked out 51 Marine Corps Shermans in the battle. Many more tanks sustained damage in the fighting but were recovered and restored by hard-working maintenance crews, the unsung heroes. As a result of their ingenuity, the assault infantry battalions never lacked for armored firepower, mobility, and shock action. The concept of Marine combined-arms task forces was now well underway.
[Sidebar (page 34):]
TheSherman M-4 medium tank employed by the seven Army and Marine Corps tank battalions on Okinawa would prove to be a decisive weapon—but only when closely coordinated with accompanying infantry. The Japanese intended to separate the two components by fire and audacity. “The enemy’s strength lies in his tanks,” declared Lieutenant General Mitsuru Ushijima before the invasion. Anti-tank training received the highest priority within hisThirty-second Army. These urgent preparations proved successful on 19 April when the Japanese knocked out 22 of 30 Sherman tanks of the 27th Division, many by suicide demolitionists.
The Marines fared better in this regard, having learned in earlier campaigns to integrate infantry and artillery as a close, protective overwatch to their accompanying tanks, keeping the “human bullet” suicide squads at bay. Although enemy guns and mines took their toll of the Shermans, only a single Marine tank sustained damage from a Japanese suicide foray.
Lieutenant Colonel Arthur J. Stuart commanded the 1st Tank Battalion during the Okinawa campaign. The unit had fought with distinction at Peleliu a half-year earlier, despite shipping shortfalls which kept a third of its tanks out of the fight. Stuart insisted on retaining the battalion’s older M-4A2 Shermans because he believed the twin General Motors diesel engines were safer in combat. General del Valle agreed: “The tanks were not so easily set on fire and blown up under enemy fire.”
By contrast, Lieutenant Colonel Robert L. Denig’s 6th Tank Battalion preferred the newer M-4A3 model Shermans. Denig’s tankers liked the greater horsepower provided by the water-cooled Ford V-8 engine and considered the reversion to gasoline from diesel an acceptable risk. The 6th Tank Battalion would face its greatest challenge against Admiral Minoru Ota’s mines and naval guns on Oroku Peninsula.
The Sherman tank, much maligned in the European theater for its shortcomings against the heavier German Tigers, seemed ideal for island fighting in the Pacific. By Okinawa, however, the Sherman’s limitations became evident. The 75mm gun proved too light against some of Ushijima’s fortifications; on these occasions the new M-7 self-propelled 105mm gun worked better. And the Sherman was never known for its armor protection. At 33 tons, its strength lay more in mobility and reliability. But as Japanese antitank weapons and mines reached the height of lethality at Okinawa, the Sherman’s thin-skinned weak points (1.5-inch armor on the sides and rear, for example) became a cause for concern. Marine tank crews had resorted to sheathing the sides of their vehicles with lumber as a foil to hand-lobbed Japanese magnetic mines as early as the Marshalls campaign. By the time of Okinawa, Marine Shermans were festooned with spot-welded track blocks, wire mesh, sandbags, and clusters of large nails—all designed to enhance armor protection.
Department of Defense Photo (USMC) 123166
Department of Defense Photo (USMC) 123166
Department of Defense Photo (USMC) 123166
Both tank battalions fielded Shermans configured with dozer blades, invaluable assets in the cave fighting to come, but—surprisingly—neither outfit deployed with flame tanks. Despite rave reports of the success of the USN Mark I turret-mounted flame system installed in eight Shermans in the battle of Iwo Jima, there would be no massive retrofit program for the Okinawa-bound Marine tank units. Instead, all flame tanks on Okinawa were provided courtesy of the U.S. Army’s 713th Armored Flamethrower Battalion. Company B of that unit supported the IIIAC with brand-new H-1 flame tanks. Each carried 290 gallons of napalm-thickened fuel, good for two-and-a-half minutes of flame at ranges out to 80 yards. The Marines received consistently outstanding support from this Army company throughout the battle.
The Marines employed the newly developed T-6 “Tank Flotation Devices” to get the initial assault waves of Shermans ashore on L-Day. The T-6 featured a series of flotation tanks welded all around the hull, a provisional steering device making use of the tracks, and electric bilge pumps. Once ashore, the crew hoped to jettison the ungainly rig with built-in explosive charges, a scary proposition.
The invasion landing on 1 April for the 1st Tank Battalion was truly “April Fool’s Day.” The captain of an LST carrying six Shermans equipped with the T-6 launched the vehicles an hour late and 10 miles at sea. It took this irate contingent five hours to reach the beach, losing two vehicles on the reef at ebb tide. Most of Colonel Stuart’s other Shermans made it ashore before noon, but some of his reserves could not cross the reef for 48 hours. The 6th Tank Battalion had better luck. Their LST skippers launched the T-6 tanks on time and in close. Two tanks were lost—one sank when its main engine failed, another broke a track and veered into an unseen hole—but the other Shermans surged ashore, detonated their float tanks successfully, and were ready to roll by H plus 29.
Japanese gunners and mine warfare experts knocked out 51 Marine Corps Shermans in the battle. Many more tanks sustained damage in the fighting but were recovered and restored by hard-working maintenance crews, the unsung heroes. As a result of their ingenuity, the assault infantry battalions never lacked for armored firepower, mobility, and shock action. The concept of Marine combined-arms task forces was now well underway.