The P-38 and surprisingly also the P-47 had a tendency to break apart in compressibility dives. Not until the addition of dive flaps (on both the P-38 and the P-47) was this problem fixed. However these weaknesses are not modeled in the game.
From p-38online.com:
"Kelly Johnson would issue a report early in 1942. In the "Study of Diving Characteristics of the P-38", Johnson would state that at a critical airspeed, which varies in altitude, a certain condition exists which causes problems with the airflow. The airflow over the surface area of the wings would separate to produce a special form of stall. At higher speeds, flow separation spreads over the upper surface, and the aircraft tends to be nose-heavy due to a shift in the center of lift. This caused a loss of pitch control. Lockheed engineer Phil Coleman originally specified a dive test plan as early as 1940. He stated that vertical dives should be initiated at 35,000 at modest power settings. The dive would continue until reaching a constant speed at 16,000 ft., and would continue until 13,000 ft. The pilot would then execute a 3 - 4 'g' pullout. The pullout should be completed at 7,000 ft., and should never exceed 570 mph.
Most early combat operational models would suffer from the compressibility problem. However, the problem was not experienced in all theaters of operation. The P-38 did not have compressibility issues while operating in India, the Mediterranean, or in the Pacific. This was primarily due to the nature of combat. In these areas, combat rarely took place above 25,000 ft., and compressibility would not occur if a dive was initiated below 25,000 ft. In Europe, combat operations were normally conducted at high altitudes. Soon, German pilots knew if they were in a bad situation, they could easily dive to safety. The P-38 would be able to dive faster than German fighters, but P-38 pilots were probably more scared of a high-speed dive than enemy fighters.
After extensive testing, the answer to the problem was the use of a dive flap (or brakes). These flaps would be attached to the main spar under the wing. This would offset the loss in lift while in high-speed dives, and would allow the pilot to remain in control throughout the dive. Test pilots Tony Levier and Milo Bircham began a series of dive tests with the flaps. Lt. Benjamin Kelsey was sent by the Air Corps to evaluate the progress of the dive flaps. He took the modified P-38 and proceeded to enter the dive. He had problems engaging the flap as he was beginning his dive. While in the dive, he experienced normal compressibility problems because the flaps were not activated, and the violent thrusts sheared the tail off from the main structure. Kelsey was able to bail out and only sustained a broken ankle. The aircraft was totally destroyed. Another test P-38 would not be fitted with dive flaps for a few months.
Finally, another test P-38 was fitted with the dive flaps and testing was resumed. The Air Corps wanted Lockheed to test the aircraft with 2,000 lbs. of more weight and to start dives at 35,000 ft. The extra weight would cause additional acceleration of the aircraft during its dive, and would approach the critical Mach number sooner. This would be even more hazardous than before. Levier and Bircham resumed testing and would start at a 45-degree dive, and increase each test dive an additional 5-degree until they encountered problems. Levier was the first to encounter problem while using the dive flap. He was in a 60-degree dive, and began having problems when we reached 31,000 ft. The aircraft began to get away from him, even with the flaps deployed. Levier was fighting the aircraft to prevent it from tucking under itself as if it were in a regular dive. He decided to ride it out to see what would happen. He began his recovery at 20,000 ft., but he would not really begin to regain control until he was at 13,000 ft. The instruments registering the strain on the airframe were all over the 100% limit load. Bircham eased it back to the base without putting further stress on the aircraft. This was the evidence they needed to prove the flaps would hold up under an extreme dive, and not lead to disaster like many P-38s prior.”
