At the time, the Luftwaffe's main single-engine, single-seat fighter was the Messerschmitt Bf 109. Some advantages helped the Spitfires win dogfights, most notably manoeuvrability: the Spitfire had a higher rate of turn and a smaller turning circle than the Messerschmitt. There are several accounts of Bf 109 pilots being able to outturn Spitfires, mainly because inexperienced pilots did not turn as tightly as was possible through fear of getting into a high-speed stall. Overall, the aircraft were closely matched in performance and the outcome of combat was largely decided by tactics, position and the skill of the opposing pilots.
One major advantage enjoyed by the German Jagdgeschwadern was the use of better tactics. In the late 1930s Fighter Command were not expecting to be facing single-engine fighters over Britain, only bombers. With this in mind a series of "Fighting Area Tactics" were formulated, involving manoeuvres designed to concentrate a squadron's firepower to bring down bombers: with no apparent prospect of escorting fighters to worry about, RAF fighter pilots flew in tight, vee-shaped sections of three. The pilots were forced to concentrate on watching each other, rather than being free to keep a lookout for enemy aircraft. "Fighting Area Tactics" also stipulated that RAF fighter pilots were to open fire at long-range, usually 300 to 400 yards (274 to 365 m), and then break off without closing in. The usual practice was to bore-sight their guns on the ground to create a shotgun pattern at this distance.
Luftwaffe fighter pilots, flying combat formations perfected in Spanish Civil War, and utilizing proved principles of the First World War, entered the Second using the basic unit of a pair (Rotte) of widely spaced fighters. They were separated by about two hundred yards. The leader was followed to starboard and to the rear by his wingman, who was trained to stay with his leader at all times. While the leader was free to search for enemy aircraft, and could cover his wingman's blind spots, his wingman was able to concentrate on searching the airspace in the leader's blind spots, behind and below. Two of these sections were usually teamed up into a flight (Schwarm), where all of the pilots could watch what was happening around them. Because the four 109s were spread out four-abreast the Schwarm was hard to spot, unlike the RAF vee formation, and all of the 109s were able to attack and defend, or retreat in pairs, whereas the RAF formations were often split up into individual aircraft which were then extremely vulnerable. The loose Schwarm, because of the reduced risk of collision between aircraft, were also able to climb faster and higher than the tightly grouped RAF fighters, which is one of the reasons why RAF formations often found themselves being "bounced" from above. When the Luftwaffe fighter units flew as a squadron (Staffel) the three Schwarme were staggered in height and wove back and forth as a means of mutual search and protection.
With the Germans able to base their 109s in the Pas de Calais, close to the English Channel the "Fighting Area Tactics" became obsolete. Many of the RAF fighter squadrons which had not been engaged in combat over Dunkirk were slow to adapt to the fact that they would be encountering the potent German fighter over Britain. Some RAF units adopted "weavers", a single aircraft which flew a pattern behind the main squadron, which still flew in vees. The weavers were usually the first to be picked off in a "bounce" by the German fighters: more often than not the rest of the squadron did not even know they were under attack. RAF squadrons that did not learn from the Luftwaffe and adopt similar tactics suffered heavy casualties during the Battle. Leaders like "Sailor" Malan were instrumental in devising better tactics for the RAF fighters. It is no coincidence that some of the most successful RAF pilots were the Polish pilots who had been trained pre-war by their air force to fly in loose formations and open fire from close-range.
The biggest disadvantage faced by Bf 109 pilots was that, without the benefit of long-range drop tanks (which were introduced in very limited numbers in the late stages of the Battle), the 109s had an endurance of just over an hour. Once over Britain the 109 pilots had to keep an eye on a red "low fuel" light on the instrument panel: once this was illuminated they were forced to turn back and head for France. With the prospect of two long over-water flights, and knowing that their range was substantially reduced when escorting bombers or in the event of combat, the Jagdflieger coined the term Kanalkrankheit or "Channel sickness".