The P-38 was the FIRST ALLIED FIGHTER TO APPEAR OVER BERLIN. It was also the first long range fighter in the U.S. inventory. It was the first Allied fighter to be able to escort the bombers deep into Germany.
It was influential for several reasons, although it was not that influential on fighter design in W.W.II.
It had twin engines for range, speed, power, and reliability. It was an effective multi role fighter, interceptor, and ground attack platform. It had center mounted weapons for accuracy. It was an extremely stable and deadly gun platform. Almost all U.S. air dominance fighters are complex twin engine platforms, the only possible exception is the F-16, which is not really an air superiority fighter. All this from a design for a high altitude high speed INTERCEPTOR. That's right, the design of the P-38 was for a bomber interceptor, and not a true fighter plane. It was never actually design to do anything but shoot down medium and heavy bombers.
It did have its problems. First, it was originally designed with 1100 horsepower engines, and when produced horsepower increased from 1100 to over 1700, so the radiators and intercoolers were at times inadequate. It required better fuel than was commonly available in Britain. It required intense and expert maintenance to be entirely reliable. It required a dedicated expert pilot to be successful. A well trained dedicated P-38 pilot could take on ANY Axis plane short of the 262 and expect to emerge victorious. Any less than well trained pilot could expect to break even at best. It was a difficult plane to fly.
That being said, the majority of problems with the P-38 in Europe were as much or more the fault of the USAAF than the plane. Go back to the beginning of the bomber campaign, when escorts were not used. This immediately caused the majority of the P-38s to be sent to North Africa. From there, they went to Italy. The 8th AF in Europe was never able to recover from this mistake, and from 1943 on, they were extremely short of P-38s, which until the P-47 got big external tanks, and the P-51 arrived in numbers, was the only escort with the necessary range. Therefore, the P-38 was ALWAYS in short supply. Especially since the 5th AF in the SW Pacific was getting priority, because General Kenney made two or three trips stateside to ensure he got what he wanted. From 1943 until February 1944, the P-38 faced the Luftwaffe deep in Germany with only a small margin of help from the P-51. The P-47 was available in massive numbers, but could not go the distance, and the Luftwaffe would wait to attack until those mass formations of P-47s turned back.
Further, while there was a wealth of experience available from successful pilots in the MTO (remember how difficult to fly the P-38 is), none of these pilots were assigned to instruct new pilots, nor were they assigned to lead them in combat when they got to Europe. Even the very best P-38 pilots in Europe complained bitterly that they lacked experienced leadership and well trained pilots. It should be noted that the first P-51 squadrons had experienced leaders, and their new pilots were flying a plane that was easier to master in combat, even though when it was mastered it was no more effective than a well flown P-47 or P-38.
Since the P-38s were in such short supply, they were never allowed to fully develop, since until 1944 they were the only longe range escorts avaialble and as such no production delays could be accepted. This meant that any new upgrade would be either delayed or discarded. The dive flaps were delayed for this very reason, as were the improved oil coolers, intercoolers, and radiators. Further, these parts were supplied by the USAAF, and manufacturers took what they were given. Also delayed were power assisted controls which when installed, dramatically increased the roll rate, an improvement sorely needed in the P-38. Not to mention the improved cockpit heating and sealing.
The automatic controls for the oil coolers, radiators, and intercoolers were also delayed. These were necessary because poorly trained pilots did not properly manage engine temperatures, and this alone was the biggest cause of poor reliability of the P-38. Pilots simply did not keep the oil and coolant warm enough at high altitude during cruise conditions. Then, when in combat, they didn't open the cooling doors and the engines overheated.
Finally, some improvements never made production, because the short sighted USAAF and WPB never made efforts to get the secondary production at Nashville off the ground. Among these were a new 1800+ horsepower Allsison engine, the three and later four blade Hamilton Standard High Activity Paddle prop, the K-14 gyro stabilized gun sight, and the master combat control system, which with a single act set the engine and prop controls for maximum performance, switched the fuel tanks and dropped the external tanks, turned on the gun heaters, and turned on the gun sight light. All of these improvements, along with possibly a 50% increase in the number of available P-38s, as early as mid 1943, could have made a huge difference in what happened between June 1943 and the end of the war.
Poor maintenance was a factor also, no doubt the maintneance crews had no better training than the pilots. They allowed the electrical components of the Curtiss Electric prop to corrode due to exposure to harsh weather in Europe (the Curtiss prop should never have been there, the Hamilton Standrard prop was hydrostatic, and far more reliable, the use of the Curtiss prop was an inexcusable erro on the part of the USAAF). This caused the props to "run away" and blow the engines, and also caused the circuit breaker and fuses to blow in the prop controls, not to mention overloading the electrical system, burning out the generator and wiring. They also failed to properly maintian the engines and engine controls themsleves. This caused more overheating, and caused rough running and engine damage.
Until Doolittle took over, no one in the 8th AF had the good sense to assure that the proper fuel was available either, and the British fuel was not acceptable for use in the P-38, the octane was too low, and the fuel would not stay properly blended, the octane raising components and the lead used to lubricated the valves and seats fell out of suspension in the intercoolers, causing detoantion and burnt valves.
Had the 8th AF merely kept their P-38s, and had the foresight to get the same drop tanks for their fighters that were used in the SW Pacific, not only would there have been plenty of P-38s, but the P-47 would have been able to go the distance in mid 1943. The effect of double the compliment of P-38s, and the full compliment of P-47s going all the way to the target would have meant air dominance by the Allies in mid to late 1943, as opposed to April of 1944. It would be difficult to tally the number of lives of bomber crews and fighter pilots saved.
For all the fluff about the P-51, several things are forgotten. The P-51 had several glaring problems. From their introduction until February of 1944 and later, there were two major problems, the first of which was a continual propensity to foul plugs, resulting in rough engines and aborted missions. The other remains to this day. Merlin engines are known to develop cracked cylinder heads. This dumps the coolant quickly. Merlins are incapable of tolerating low coolant conditions, and the small narrow bearings sieze very quickly. The P-51 simply is not the invincible all conquering plane popular history leads most to believe.
The P-47 had the fewest problems of all, and was available in far greater numbers at least until mid to late 1944. Tough, rugged, reliable, and effective, its only real drawback was range, and no one in the 8th really made serious attempts to solve this problem and use the large tanks used in the SW Pacific until 1944.
By the way, the date at which the P-51 actually even equalled the P-38 in numbers deployed in Europe was sometime in April of 1944.
As far as influencing the war effort, the P-47 and the P-38 go much further than the P-51. While what it (the P-51) could do (long range and high speed) did influence the design requirements for fighters, not many of its actual design features are carried on todays fighter aircraft. The plane that most resembles the P-51 in the current inventory is the F-16, which is a relatively cheap and simple multi role plane compared to the F-15, F-18, and F-22, which are twin engine, complex, heavily automated, air dominance fighters capable of multi role use. Hmm, large, twin engine, complex, air dominance, multi role use, wonder which W.W.II fighter that most resembles?
