In the spring of 1941 General Claire Chennault, who had been in China since 1937 and knew Japanese well, began warning his superiors in Washington about the new superfighter just introduced by Japan. His memorandum outlining the lessons learned by the Flying Tigers, which flew the early model P-40B, quickly circulated between air commanders:
Concerning the P-40 and Zero the Universal rules are:
Take advantage of the sun and clouds whenever possible. Keep Looking Around. Never remain intent on a target, a flight of the enemy, or even one part of the sky for very long. Danger might be coming from any direction. Take one last look before making an attack, and take another good look as you break away. If possible, also take a good look around just before you come within firing range of your target. Basic tactics adopted with P-40s against Japanese fighter of superior maneuverability:
- Never use climbing maneuvers unless you have excess speed from a dive because the Jap plane can outclimb you.
- Use the P-40’s best characteristics; namely – speed, diving and firepower (head-on runs). Never use maneuverability. Avoid aerobatics because the Jap planes can do them faster and in much less space. Never dogfight them.
- Altitude is good life insurance. if the enemy has two or three thousand feet altitude advantage on you, turn at right angles to his course, or even directly away from him and avoid him until you have enough distance to climb safely at least to his altitude. Climbing straight up into an enemy formation at 150 MPH is almost a sure way to lose pilots and equipment.
- If you have to bail out while the enemy is in the vicinity, wait as long as possible before opening your chute, because if Jap sees you, he will machine-gun you.
- Be patient; use the clouds and sun, and wait until you have an altitude advantage before attacking. If you have to dive away from the attack, it will take you twenty minutes to get back into it again. If you have an initial altitude advantage, you can dive, fire and climb again and repeat at very close intervals, thus doing more damage.