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Background

T he P-38 Lightning was one of the world’s fastest aircraft when it first flew

early in 1939. Its eccentric design was immediately seen as exciting rather than off-putting: its airframe featured twin “booms” and a cockpit “pod” in place of a traditional fuselage.

The Lightning was, in fact, one of the US Army Air Force’s (USAAF) most important aircraft during the war. Its combination of speed, fast rate of climb, heavy armament, long range and good cockpit visibility made it at least somewhat successful in all its roles. There was one campaign, however, in which—according to the conventional narrative—the P-38 failed: escorting US bombers in Operation Pointblank, the daylight strategic bombing campaign against Germany. Many historical accounts are dismissive of the Lightning and its service in that costly effort. In

short, it’s almost always described as having been overshadowed by the P-51 Mustang, a fighter that proved to be an ideal long-range escort.

It would be wrong, though, to simply downplay the P-38. They provided the bulk of long-range escort fighters during the critical operations of January through March 1944, the decisive period during which the USAAF gained full ascendancy over the Luftwaffe. For example, during “Big Week” (20-26 February 1944) two of four long-range fighter groups serving Eighth Air Force, based in England, and all three long-range fighter groups with Fifteenth Air Force, based in Italy, were P-38 units.

To understand the P-38’s true significance during that crucial period, it’s therefore necessary to understand the overall strategic bombing campaign. Lightnings were brought in because the campaign’s founding

assumption—that bombers could protect themselves against enemy fighter interceptors—wasn’t working.

Strategic Dilemma

Prior to the war the US Army Air Corps (the USAAF’s prewar organi-zational predecessor) had developed the strategic doctrine of “daylight precision bombing.” Air Corps thinkers believed the long-range heavy bomber to be the supreme weapon of future war. The B-17, first flown in 1935, was developed to operationalize that idea. Heavily armed, structurally robust, faster than most of its contemporaries, and bombing from altitudes in excess of 30,000 feet, the B-17 would indeed prove an effective instrument for daylight bombing. The newer B-24, with the same heavy armament, longer range and even heavier bomb load, was also built for the same mission.

Air Corps doctrine further mandated bombers alone would dominate future air war. Its leaders shared the view of most air com-mands at the time: fighters would be secondary, serving mainly the political necessity of providing token protection for the homeland against enemy bombers, while the true path to victory via airpower lay only in sending your bomber fleet to annihilate the opposition’s homeland before he could do so to yours.

As the air war developed, the USAAF high command stubbornly adhered to the view its bombers’ fire-power, when combined with massed formation flying in tight “combat

boxes,” could defeat German intercep-tor attacks. By the late summer of 1943, that view was clearly out of date.

In fact, as early as 1940 the Battle of Britain had shown that fighters, assisted by radar and ground intel-ligence and control networks, could dependably generate unacceptable losses to bombers attacking in day-light. Even with limited fighter escort, the Luftwaffe had been unable to over-come the Royal Air Force’s (RAF) coor-dinated defense system. Similarly, by the summer of 1943, even the USAAF’s most doctrinaire strategic bombing advocates understood Luftwaffe fighters were bringing down too many bombers. Short-range Spitfire and

P-47 Thunderbolt fighters helped, but they couldn’t escort the bombers all the way to targets deep in Germany.

The USAAF therefore began experi-menting with “drop tanks’” to extend the range of its P-47 fighter escorts. By the second Schweinfurt Raid in October 1943, P-47s could accompany the bombers slightly past the German border. That helped, but German fighters just hung back until the escorts turned away. The USAAF therefore still needed long-range fighters to accompany the bombers the whole distance to targets deep in Germany.

In a series of raids deep into Germany from 4 through 14 October 1943, Eighth Air Force lost 160 bomb-

The P-38 Lightning in Europe

By Jonathan Lupton

With one engine out and a propeller feathered, a P-38 flies home protected by heavily-armed B-17s.

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Strengths & Weaknesses of an Unorthodox Fighter

Nothing was average about the P-38 Lightning. It was a successful twin-engine day fighter in a war in which single-engine fighters predominated. It introduced tricycle landing gear, clear-glass “bubble” canopies, and could outrange any single-engine fighter during the early war years. Its twin-boom layout was unusual though not unique.

When the Lightning first flew in 1939, its 400 mph maximum speed seemed like something out of science fiction. Its performance dropped off with altitude, though it remained one of the fastest fighters through the mid-war period.

Other US fighters had wing-mounted machineguns that had to be synchronized to converge their fire at specific ranges. The Lightning was more heavily armed, with a 20mm cannon and four machineguns, all mounted in the nose for straight shooting.

With a 52-foot wingspan and its twin-engine configuration, the P-38 wasn’t as nimble in dogfights as some single-engine fighters. Its ability to roll was particularly inferior to that of single-engine planes. Yet it held advantages beyond good speed and rate of climb. For instance, because its counter-rotating propellers neutralized torque, the P-38 had good turning ability, especially at low speed.

For those reasons, the Lightning could be a dangerous opponent. Luftwaffe fighter pilots who flew against it in the winter of 1943-44, includ-ing aces Gunther Rall and Heinz Knoke, never disparaged the P-38.

The Lightning’s most crucial limitation was in high-speed dives. The problem was not a lack of speed, but rather an excess of it. That is, when pushed into a dive over 375 mph, the Lightning tended to quickly gain great speed, pushing the airflow over parts of its frame to near supersonic velocity. That caused a form of turbulence known as “compressibility,” which could lock the controls and then shake apart the plane.

In air combat that meant P-38 pilots had to avoid extreme dives. One of the German fighters’ favorite tactics was to make head-on attacks against the bombers, followed by tight rolls and high-speed dive aways. The Lightnings couldn’t follow. The diving problem also deprived Lightning pilots of their own otherwise useful escape maneuver. The problem was eventually solved in later models, but the versions available in 1943 and early 1944, the P-38H and early versions of the P-38J, simply had to avoid high-speed dives.

One of the Lightning’s most serious limitations is little mentioned in most accounts: cost. The Lightning was a high-tech aircraft that didn’t lend itself well to mass production. Despite efforts to improve production efficiency, Lightnings cost more and took longer to make than Mustangs and Thunderbolts. ★

ers. The most memorable raid of that period, a strike at the Schweinfurt ball bearing works, beyond the range of P-47 protection, cost 60 bombers—20 percent of the attack force. Those disastrous losses generated a more determined push toward finding an escort fighter solution. Two already existing aircraft types showed potential for the role: the Lockheed P-38 Lightning and the North American P-51B Mustang. Accordingly, on 29 October, Gen. Henry Harley “Hap” Arnold, head of the USAAF, ordered all production of those two planes sent to Eighth Air Force, despite pressing needs for them in other theaters.

Neither of those planes had been designed to serve as long-range bomber escorts. The P-38 was originally developed as an interceptor, while the P-51 had an even more off-center history: it had initially been intended for use by the RAF as a low-altitude fighter-bomber and reconnaissance aircraft.

Of the two, the P-38 was more readily available. Already in service at the war’s start, it had been steadily developed through a series of models, from the F through G, H and J versions by the winter of 1943-44. Noted for its long range and heavy armament, the P-38 had a good, though not stellar, record in air-to-air combat against the Luftwaffe’s FW-190 and Me-109 fighters.

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War Emergency Power & Allison Time-Bombs

When P-38s began escorting bombers over northern Europe, seri-ous problems cropped up. Engines would give out, sometimes deto-nating or throwing piston rods in flight. Pilots were understandably enraged when their engines went dead, sometimes in the middle of combat. The P-38 engines acquired the unflattering nickname “Allison time -bombs.” (Allison being the company that manufactured them.)

There were several contributing factors. The high altitude required to escort the bombers—up to 35,000 feet—combined with the extremely cold skies of northern European winter, put stress on the engines not previously encountered. Inexperienced pilots and ground crews knew little of the procedures necessary to get reliable perfor-mance from them under such conditions. In turn, some of the informa-tion officially provided for dealing with the situation proved wrong.

Much of the problem stemmed from the P-38’s still ongoing development process. During the winter of 1943-44 the G and H models were supplanted by the more powerful J. That was a change for the better, but it created vexing new problems. For one, the J model was the first version designed to use War Emergency Power (WEP or “overboost”).

The advent of WEP had marked a turnaround for the USAAF. Prior to the war, American engine-makers and the Army Air Corps had been conservative about engine operations. A full year after Pearl Harbor, the USAAF still required all engines pass a 150-hour test regime at maximum power. To meet that rigorous reliability standard, manufacturers like Allison rated their maximum settings below their true potential.

In comparison, the British had years earlier recognized the need for WEP, which meant running an engine at higher power settings than recommended by the manufacturer in order to squeeze out extra speed during combat. As an RAF document put it: “In view of the risks pilots have to take, manufactur-ers should be prepared to risk their engines as well.”

In practice, while WEP stressed engines, if pilots limited it to bursts under 10 minutes, and if ground crews performed

rigorous maintenance after each use of WEP, the mechani-cal lifetime of the plane wasn’t drastically reduced.

The J and later versions could be distinguished from earlier Lightnings by their deeper nacelles, which housed a larger “intercooler” beneath the engines. They replaced weaker intercoolers in the leading edges of the outer wings. By more effectively cooling the air entering the engine from the Lightning’s turbo-supercharger, the new nacelle intercoolers allowed the Js to run their engines to 1,600 hp, compared with 1,425 in previous models. With WEP, a J could reach 422 mph at 25,000 feet, a five percent increase over the 400 mph maximum for the earlier G.

Of course, the use of WEP in the air required higher maintenance standards on the ground. The Lightning was already a demanding aircraft for ground crews, with dense internal piping and wiring, and little open space in its tightly streamlined engine cowlings. Investigations showed the ground crews didn’t always change all the exhaust plugs after pilots had used WEP, often creating trouble on the next flight. The maintenance problems were eventually worked out, but only after the crucial late-winter air battles of 1943-44. Many Lightnings and their pilots were lost during that costly climb up the learning curve. ★

B-17s flying in combat box formations for mutual protection.

Lockheed P38-J Lightning

A P-38 engine. Note the tight fit.

Attrition warfare up close: the end for a B-24.

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February, in what became known as “Big Week,” Eighth Air Force bombers from England, and Fifteenth Air Force bombers from Italy, launched daily attacks. The bombers sustained heavy losses some days and light losses on others, but they struck targets relent-lessly and heavily. Many bombers were lost—247 destroyed outright plus many more badly damaged—but by then that number represented just 6.5 percent of the entire force, and it was a rate the USAAF could sustain. Escort fighter losses were just 28, around three percent.

There’s no way to count how many bombers would’ve been lost had there been no P-38s providing escort, but those extra losses—and the resulting loss in the bombing’s effect—would

A Numbers Game

The Anglo-American combined bomber offensive was a campaign of attrition: the grim arithmetic of aircraft and crew losses weighed against damage done to the enemy. To win, the Allies had to keep their losses within accept-able limits. In turn, there were two dimensions to that: morale and rate of replacement.

Morale was essential. Though the topic was seldom discussed openly, those in command knew a lot depended on the willingness of bomber crews to continue playing airborne Russian roulette with German fighters and flak. While most mission aborts were called for mechanical reasons, there was a morale factor involved in many of them. Similarly, not every US bomber that strayed into neutral Switzerland, and was then shepherded to a landing by the Swiss Air Force, did so by accident.

Yet morale remained strong enough, mak-ing the second factor—rate of replacement—ultimately the more important. Losses had to be low enough to be replaced, both by newly made bombers and newly trained crews, as well as by

the workshops in England that performed minor miracles turning mangled, bullet-pitted B-17s and B-24s back into flyable fighting machines.

By October 1943 the deep penetration raids into Germany had become unacceptably costly. While not always in the Schweinfurt 20 percent range, mission losses of 10 to 15 percent were still too high to maintain strength levels, let alone expand the bomber force to 41 groups as was planned for July 1944.

From November 1943, bomber losses began to drop. That correlated with the arrival of the first long-ranged P-38s for escort duty, but that correlation must be used with care.

Part of the explanation for the lower losses was weather. During December 1943 and January 1944, overcast skies became nearly constant above northern Europe while Eighth Air Force began using new H2X radar to bomb through clouds. Those conditions also made it harder for the Germans to intercept. The climbing Luftwaffe fighters had to contend with icing and visibility problems as they ascended through the murk, having to depend heavily on radar to find the approaching bombers. Fewer interceptions meant lower bomber losses,

yet radar bombing was still primitive and after-action reconnaissance flights showed those early winter missions did little damage.

At the same time, USAAF raids continued growing in size. While the Luftwaffe was able to build up its home defense fighter force somewhat, it couldn’t match the growing avalanche of fighter and bomber groups regularly arriving from the United States. Accounts from Luftwaffe fighter pilots describe massive streams of aircraft constantly heading into Germany on the “bomber autobahn.” Those pilots felt they were fighting a war against impossible odds.

The magnitude of USAAF growth is shown by the costly Oschersleben raid of 11 January 1944. Despite all-the-way escort from P-47s, P-38s and P-51s, the Luftwaffe fighters and flak brought down 60 bombers—as many as during the Schweinfurt raid of 14 October 1943. Yet such losses by then represented only nine percent of the 663 bombers dispatched. That loss rate was still painful, but it represented half the rate of the fateful October mission.

Even so, despite those other factors, escort fighters made the biggest difference. Statistical

analysis showed bomber losses dropped by two-thirds to a half when all-the-way escorts were on hand. For example, during Big Week, Fifteenth Air Force bombers attacked the Messerschmitt plant at Regensburg, beyond the range of its P-38s, on 25 February 1944. The Luftwaffe savaged the bombers while they were outside escort range: losses were 19 percent. When Lightnings arrived to provide withdrawal support, they tangled with the German fighters, claiming two Me-109s and six twin-engine Zerstorer for the loss of two of their own. Just as important, the bombers’ ordeal was immediately ended.

The per-sortie loss rates of escorting P-38s and P-51s were roughly equal during the critical period from November 1943 through March 1944. The difference was their kill rates. Mustangs accounted for substantially more shoot-downs, but bomber pilots knew they were safer with “little friends” along on their missions, whether they were Mustangs or Lightnings. ★

more apt than he knew, given the icy conditions in those P-38s’ cockpits.

P-38s also tended to develop engine problems. That was due to multiple factors, and was therefore difficult to fully remedy. Severe cold stressed the engines, often by freezing the cooling system, ironically making the engines overheat in the frigid high altitude air. There were also problems caused by improper maintenance, undependable fuel quality and technical changeovers involved with the new J model.

Operation Argument & Big Week

Allied plans called for an invasion of France in the late spring of 1944. To guarantee its success, the USAAF needed to take control of the skies from the Luftwaffe. As soon as the worst of the winter weather abated, Eighth Air Force therefore had to launch a renewed and sustained attack on Germany. Codenamed Operation Argument, it was to be a campaign aimed at the factories turning out aircraft—especially fighters—and associated equipment like engines, ball bearings and aluminum.

A ridge of high pressure developed over the Baltic and Germany in late February 1944, temporarily clearing the north European sky. From 20 to 26

Much was expected of the P-38s assigned to the bomber offensive, yet problems developed. To escort bombers in northwestern Europe, the Lightnings had to fly for several hours at a stretch at high altitudes, sometimes above 30,000 feet, where air temperatures averaged -50° Fahrenheit in winter. Those low temperatures, not encountered by the P-38s in the Mediterranean or Pacific, were hard on both aircraft and crews.

The P-38 was a particularly cold aircraft, because the pilot sat in a pod separated from the engines. With no conductive warming effect, and only an inadequate heating system to channel warmth from the nacelles, pilots suffered in their aptly dubbed “airborne ice wagons.” No matter how thickly they dressed, Lightning pilots eventu-ally got numb extremities. Worse, the extreme cold dulled their senses.

One German account related how, on 7 January 1944, a group of Me-109s jumped some P-38s of Fifteenth Air Force’s 1st Fighter Group over Yugoslavia as they were returning from an escort mission. The 109s shot down six Lightnings without a loss of their own. In his after action report, the German flight leader noted the Lightning pilots had flown “stiffly,” like “cave men.” That assessment was

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Airborne Ice Wagons

The first P-38 unit tasked to take part in the bombing offensive, 55th Fighter Group, became operational on 15 October 1943—the day after the climactic Schweinfurt raid. The 55th’s P-38s flew their first escort mission on 20 October. In December they were joined by P-38s from 20th Fighter Group.

By late 1943, P-38s were escorting bombers on long-range missions whenever northern Europe’s overcast skies permitted bombing. On 3 November, 55th Fighter Group scored a notable success during an escort mission, shooting down a total of seven German fighters over Holland. The Germans had been surprised to find escorts that far from England.

The P-38 groups were joined in December by the 354th Fighter Group, which brought the first P-51B Mustangs to Europe. Together those three fighter groups, mustering between 90 and 110 fighters on a typical day, offered Eighth Air Force its first all-the-way escort into the skies over Germany. Fifteenth Air Force, based in Italy, meanwhile had to rely on three understrength P-38 groups for its total escort force.

The willingess of men such as these simply to keep flying was crucial.

The P-38J had a deeper under-nose scoop, with a stronger intercooler that allowed higher engine settings for a small but important boost in speed.

Earlier P-38 models, including the P-38G and P-38H, had a smoother, more aerodynamic nose, but had to use lower engine settings.

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