Tactics Over Technology: The Thach Weave

One little known aspect of the June 1942 Battle of Midway was that it wasn't just the turning point in the Pacific War that started to roll back the Japanese Empire, but it also was a turning point in fighter tactics that changed the way air combat was conducted. At the start of the Second World War, US Navy fighter squadrons had eighteen aircraft that were divided into six sections of three planes each- each section was composed of a flight leader and two wingmen. However, well before the attack on Pearl Harbor, the Navy fighter squadrons VF-2 and VF-5 experimented with two-plane sections with a flight leader and a single wingman. In a three-plane section it was found that the wingmen tended to focus too much on formation keeping instead of being on watch for enemy aircraft. The shift to a two-plane section with the wingman staggered and below the lead's altitude lessened the need for strict formation keeping. As a result, the two-plane section became the basic unit of the Navy's fighter squadrons beginning in July 1941. Three sections then made up a division in the squadron for a total of six planes- in cruising, each of the three sections flew in trail, but nearing combat they assumed an echelon formation. Having the support of a single, more vigilant wingman improved the odds of survival particularly against the superior Mitsubishi A6M Zero fighter.

That summer, Lt. Commander John "Jimmy" Thach, commander of VF-3, was still stateside and undergoing conversion with the rest of his squadron in California from the troublesome Brewster F2A Buffalo to the more robust Grumman F4F Wildcat. While there, Thach had access to preliminary reports from the American Volunteer Group "Flying Tigers" in China on the phenomenal performance of the Japanese Zero, possesing maneuverability and a rate of climb well in excess of their new F4F Wildcat mounts. At the time Thach was already well-known to his men for using matchsticks on a table to come up with new tactical ideas for his aircraft. Now he was back to his kitchen table each night, playing with matchsticks trying to come up with a tactic to counter the exceptional maneuverability of the Zero. Thach's first conclusion was the standard three-section division was unsuitable. It was better to use just two sections with a total of four planes. But how to use them? Thach would deploy two sections of Wildcats flying abreast of each other at a distance that approximated the turning radius of the Wildcat. Because of their positioning abreast and at a distance, each section had a good view of the other section's six-o'clock position. When Zeroes engaged, they'd be forced to choose one section to attack and could be spotting by the other section. This is one key characteristic that set apart what Thach called his "beam defense position" from other similar weaving tactics- a commitment to be on lookout for the other section. 

Once a section was attacked, the other section either signaled the other one or just turned in towards that section under attack. Once alerted, the section under attack turned towards the incoming section. If the Zero pressed its attack, it faced a head on attack from the incoming section and if it withstood that, it would find itself in a position with the incoming section having another firing pass as each section weaved in and out from each other. If the Zero broke off the attack, then it faced having the incoming section getting on its tail. Thach also considered that the weave could also work on with just a single section if one fighter was engaged, the other fighter in the section could set up the weave. Wanting to prove it worked, Thach decided to test his ideas with the pilots of VF-3. Four planes were to play the part of the defenders flying in two sections. Thach was one of them. Another group of squadron pilots would play the part of the attackers- in his tests, Thach selected his best pilot, future Medal of Honor winner Edward "Butch" O'Hare, to lead the attacking group. To simulate the performance advantage of the Zero, Thach and the "defending pilots" would limit their Wildcats to just 1/2 power while O'Hare and the attacking pilots would get to use the full power of their Wildcats. Instructed to attack from different angles and altitudes, O'Hare found that once the "defenders" set up the weave from their beam defense position, they always found themselves facing the guns of one section or the other irrespective of their performance advantage. 

At the Battle of Midway, VF-3, led by Thach, were embarked on the USS Yorktown. Tasked with covering a group of plodding Douglas TBD Devastators, Thach was leading two sections at higher altitude. When the Devastators were jumped by Zeroes, Thach was unable to fly to their aid as his group had also been attacked by a group of Zeroes. In their initial firing pass, one of the four Wildcats was downed, but Thach had the remaining Wildcat set up a weave with his section. In short order, three Zeroes were shot down as the Zero pilots tried to aim on the weaving Wildcats and found themselves exposed to Thach and his men on repeated firing passes. Although Thach wasn't able to save the Devastators, the "Thach Weave" proved its worth in battle and word spread amongst Wildcat pilots that they now had a tool with which to fight the much-vaunted Zero. 

Thach's tactical genius was recognized after Midway and later in the war developed what was called the "Big Blue Blanket" defense against kamikaze attacks which was a layered defense using round-the-clock combat air patrols of Grumman F6F Hellcats and Vought F4U Corsairs as far away as possible from the carrier to catch the kamikazes early. Fighter sweeps were conducted over Japanese airfields to prevent kamikazes from getting airborne, and destroyer radar pickets were stationed as far as 50 miles from the main carrier force. During the Korean War Thach commanded the carrier USS Sicily and then after the war, captained the USS Franklin D. Roosevelt. In 1959 he was assigned to the Navy's antisubmarine warfare development unit with the ASW carrier USS Valley Forge as his flagship. His contributions to ASW tactics were so significant he was featured on the cover of Time Magazine and the Thach Award was later established for the best ASW squadron in the Navy. The Perry-class frigate USS Thach (FFG-43) is named in his honor. 

But he is best known for the Thach Weave and basic principles of the weave are still in use to this day in modern fighter combat. The Thach Weave was also used by Doulgas SBD Dauntless dive bombers in the Pacific- being much slower, the Dauntless were vulnerable to the Zero as well, but by employing the Thach Weave, the rear gunner of the Dauntless, having twin machine guns at his disposal, would have a much clearer shot at the attacking Zero during a weave. 

Source: United States Naval Fighters of World War II in Action by Michael O'Leary. Blandford Press, 1980, p62-63.

The Disastrous Flop That Was the Brewster F2A Buffalo

If you'd been following my Twitter stream earlier today (@SentinelChicken), I had been posting tidbits about the failure that was the Brewster F2A Buffalo, quite possibly one of the worst fighting aircraft we sent into action during the Second World War. The saga of Brewster Buffalo not to mention the tales of mismanagement at the Brewster Aeronautical Corporation from the 1930s right into World War II would give me blog material for at least seven posts, but this evening I want to try and keep things strictly on the American combat history of the F2A Buffalo. In fact, there was only one major battle that the United States committed the Buffalo, and that was in the hand of Marine aviators at the Battle of Midway in June 1942.

When the US Navy placed an order for 54 F2A-1 Buffalos on 11 June 1938, it was the Navy's first large scale production contract for monoplane fighter aircraft. The choice of Brewster was an unusual one given that they had only established an aeronautical division in 1935 and the 1936 order of the prototype XF2A-1 was already controversial within the Navy. As insurance, the Navy also issued a contract with Grumman Aircraft for the prototype XF4F Wildcat- and a damn thing they did, too, as history has shown. From the time of the order of the XF2A-1 to the first flight in June 1938, two years had elapsed which by the state of aviation technology in the late 1930s was an extraordinarily long period of time. Technical issues beset the Buffalo flight test program and a series of design refinements were needed to get the F2A to an operational standard that satisfied the Navy. Weight was always an issue with the stubby aircraft- the first production version, the F2A-1, for example, took 30 minutes to reach 21,000 feet! By the time 108 F2A-3 were built, an additional 1,500 lbs were added to the aircraft's weight and the Navy, finally dissatisfied with the evolution of the Buffalo, passed its F2A-3s to the US Marine Corps. 

Following the attack on Pearl Harbor on 7 December 1941, the aircraft carrier USS Saratoga was tasked to deliver the fourteen F2As of Marine squadron VMF-221 to Wake Island. But as Wake had fallen to the Japanese on 23 December, on Christmas Day VMF-221 was diverted instead to Midway Island, becoming the first fighter defenses for the island bastion. Other than the occasional combat air patrol to intercept Japanese flying boats, it wasn't until April that the fortification efforts at Midway took importance once the breaking of Japanese codes indicated that the Japanese planned to take Midway in June 1942. By the end of May, 21 Marine Corps F2As made up the majority of the island's land-based fighter defenses along with 7 F4F Wildcats. On 3 June 1942 the Japanese task force had been spotted and the Marine fighters prepared for action. Seven F2As and five F4Fs were dispatched to attack an incoming formation of Japanese aircraft while twelve remained in orbit over Midway along with a single F4F to defend against a second attack that might come from another direction. 

A one-hundred eight aircraft strike force from the carrier Hiryu were intercepted by the first group and was soon joined by the second group that had been orbiting over Midway. Of the twenty-five Marine Corps pilots that set out on that day to defend Midway, fifteen were killed in action including their commanding officer, Major Floyd Parks. Thirteen F2A Buffalos were shot down by the superior Mitsubishi A6M Zero fighters along with two F4F Wildcats. Of the remaining F2As, only two were in any condition to fly again. One surviving pilot commented "Any commander who orders pilots out for combat in an F2A should consider the pilot lost before leaving the ground." That single air battle destroyed VMF-221 as a fighting unit. Its surviving personnel dispersed to help the other units defending Midway. In fact, that air battle on that morning of 3 June 1942 was the heaviest loss of Marine Corps pilots ever sustained during the Second World War! In fact, most of those pilots lost their lives in the first few minutes of the air battle. 

After the Battle of Midway, the F2A Buffalos were immediately withdrawn from front line service in US Marine Corps. All were assigned to stateside training units and even then, the Buffalo was disliked by pilots. They only lasted a few months in the role and most were scrapped with a handful going to aviation mechanic schools to be taken apart for instruction purposes. As a result, not a single American F2A Buffalo survived and none are in existence today other than examples that served with foreign nations overseas. It was the beginning of the end for Brewster as a defense contractor- in fact, just prior to the Battle of Midway, the US Navy seized control of Brewster's production plants and ousted its management. By 1946, Brewster was finally liquidated for good. 

Source: United States Naval Fighters of World War II in Action by Michael O'Leary. Blandford Press, 1980, p8-18.

In August 1948 the US Navy's Bureau of Aeronautics sent out a request for proposals (RFP) for a carrier-based long range heavy attack aircraft ("Class VA") as part of Outline Specification 111 (OS-111). The primary mission of the Class VA design was the high altitude delivery of a nuclear weapon no less than 1,700 nm from the carrier which at the time was to be the CVA-58, the USS United States but it was also implied that operation of the design from smaller vessels like the Midway class would also be beneficial. The Navy would get 8 proposals from 7 manufacturers.

Uniquely among the companies that submitted proposals for the Class VA competition, Douglas Aircraft submitted two proposals from two different teams- one from the Santa Monica Division and one from the El Segundo Division. The El Segundo Division's design was designated the Model 593 and rather unusually featured a tail dragger layout for an advanced twin jet design. The rationale for what seemed like an archaic landing gear layout was that on USS United States, the lowered tail meant that the Model 593 could be stowed in the hangar deck without folding the vertical fin. On the Midway class, only a portion of the vertical fin would have to folded instead of the entire fin. The tailwheel layout also offered ease of handing on the carrier elevators as well.

Throughout the Model 593's design process, emphasis was placed uniquely amongst the Class VA submissions to allow operations from as many types of aircraft carriers as possible from the supercarrier USS United States to the Midway class and even the smaller Essex class carriers. The twin jet design that resulted offered more flexibility and as a smaller design was lower in cost.

In March 1949 the Douglas El Segundo design and the Curtiss-Wright proposal were selected for further development. The following month, however, the USS United States was cancelled and the Navy instructed BuAer to modify the Class VA project for operation from the Midway class. As the Midway class vessels were smaller, this gave the lighter and smaller Douglas El Segundo Model 593 a strong advantage over the Curtiss-Wright design. By July of 1949 the Douglas Model 593 was selected as the winner by which point the design had been refined further and the tail dragger layout replaced with a tricycle undercarriage. The Model 593 would go into production as the A3D Skywarrior, vindicating the El Segundo team's gamble.

Source: Secret Aerospace Projects of the U.S. Navy: The Incredible Attack Aircraft of the USS United States, 1948-1949 by Jared A. Zichek. Schiffer Publishing, 2009, p9-10, 46-56, 207-211.