Rebuilt Luftwaffe!? Part II

Messerschmitt-me262

Historians over the years have pointed to Hitler’s decision on the Me-262 as an egregious error; another in a long series of meddlings which cost him the war. Most, however, have not been aware of the limitations under which the German jet was developed. There is little question that the aerodynamics and structural aspects of the plane were brilliant; it was far ahead of its time. A cruising speed of 525 mph with an endurance over an hour was a fantastic achievement for 1944 aviation technology. However, the big problem was the thing that made the propeller-less 262 such a potentially hot aircraft the Jumo 004 turbo-jet engines. As with most new technologies, the revolutionary engine experienced many teething troubles.

The turbo-jet operated at much higher temperatures and rotational speeds that any piston power-plant. Moreover, the metals usually used for high-temperature strength, alloys of nickel and chromium, were in very short supply in the Nazi inventory. The engineers were forced to rely on less-reliable substitutes. As a result, even as late as fall, 1944 the mean serviceable life of the jet engines was only eight hours for the early models! Metal fatigue created engine failures and fires were frequent. All through the summer and fall of 1944, there was always a heavily guarded convoy with replacement jet engines somewhere in Germany looking for Special Detachment E 51. Oblt. Werner Muffey remembers being happy that the Ar-234s had two turbojets:

“it was rare for a single engine to survive the 25 hours scheduled between overhauls. It was much more likely for only 5 to 10 hours to pass before something went wrong. In fact I once jealously preserved a unit for almost 30 hours which was considered a record. Then another turbojet threw several blades before I returned from my first sortie with it. After putting out a small fire in the Riedel gas tank, I returned directly to Oranienburg to change the engine.”

Even worse, German pilots flying the new aircraft learned to their horror that the turbojet was prone to suddenly quit or even catch fire when throttled too quickly. Due to the raw materials shortages, the composition of the turbine blades was not up to the loads which could be imposed upon it. The flight born discovery of “flame-out” would prove fatal to a number of pilots putting the 262 through its paces. The solution to this was to only throttle the engines slowly, a luxury that only a bomber or reconnaissance application could afford. Fighter dogfights demanded sudden acceleration and hence the first use of the Me-262 was most appropriately restricted to less taxing reconnaissance and level bombing missions.

In spite of German engineering genius, the vexing problems with the jet engine were never completely solved during the war. Then there were other mechanical problems, such as roughness in the fuel metering system, which in a piston powered plane might only mean a momentary reduction in power. In an Me-262, such mundane troubles could overheat the engine which would promptly disintegrate as it shed turbine blades. Flying a jet Me-262 was significantly less forgiving than jockeying around in a piston powered plane. Most of the pilots converting to the elite units flying this plane were very experienced, but jets represented new territory. For instance, a common even subconscious habit in piston aircraft, was to push the throttle forward to rev up the engine before easing it back. In a 262, this could drop an engine a potentially fatal mistake. There were even bizarre problems with the J2 fuel. In November and December of 1944 KG 51 experienced mysterious symptoms of poisoning in some of its pilots who had received minor burns. Sr. Warrant Officer Kohler, died after receiving only minor burns to his hands. After the cause was established as the fuel, the jet pilots were provided with leather clothing including protective gloves.

The unparalleled power of the turbojets led to other dangers never encountered in conventional piston aircraft. It was easy to exceed the airframe limits even in a steep climb full throttle would see speeds only encountered in the most daring dives in other planes. Also, unlike the howl of a piston plane under full throttle, the jet was deceptively quiet in the cockpit and a wary pilot had to be attentive to the airspeed indicator. There were high speed limits as well. Up to 570 mph the 262 operated faultlessly. However, as test pilots reached 585 mph, they found that control surfaces responded poorly. Beyond that things quickly became uncontrollable. Today, surviving Me-262 veterans reckon that a number of their compatriots succumbed to compressibility at the aerodynamic limits. Flying a V-2 chase sortie, Werner Muffey, the Technical Officer of an Ar-234 reconnaissance unit, learned that his jet powered craft could exceed the aircraft’s “envelope”:

“This was the only time I got into trouble with ‘Dr. Mach.’ Oblivious of my pilot’s duties and staring constantly down to detect the exploding V-2, I inadvertently pushed the stick forward. The vibration going through the airplane was quite dramatic, and I had some problems recovering control.”

In spite of early recognition of these problems, conversion training was not always satisfactory. Since there was no two-seater version of the 262, training flights were begun after cursory technical instruction. Usually the instructor, who often had little experience with the aircraft himself, would provide a pre-takeoff briefing, supervise the tricky start-up procedure for the engines and then talk the pilot through a flight over the radio. Often too much reliance was made of a pilot’s experience with conventional aircraft. Lt. Walther Hagenah was an experienced Fw-190 pilot from JG 3:

“Our ground school lasted one afternoon. We were told of the peculiarities of the jet engine, the dangers of flaming out at high altitude and their poor acceleration at low speeds. The vital importance of handling the throttles carefully was impressed upon us, lest the engines catch fire. But we were not permitted to look inside the cowling of the jet engine we were told that it was very secret and we did not need to know about it! By the time I reached III/JG 7 there was insufficient spare parts and insufficient spare engines; there were even occasional shortages of J-2 [jet fuel]. I am sure all of these things existed and that production was sufficient, but by that stage of the war the transport system was so chaotic that things often failed to arrive at the front-line units. In our unit, flying the Me-262, we had some pilots with only about a hundred hours’ total flying time. They were able to take off and land the aircraft, but I had the definite impression that they were of little use in combat. It was almost a crime to send them into action with so little training. Those young men did their best, but they had to pay a heavy price for their lack of experience.”

Aside from all of this, Hitler had already decided that the He-162 would be the new jet fighter and the Me-262 must carry bombs. Knowing of the coming invasion of France, he was fixated on the idea of German jets dropping bombs on the heads of the Americans on the beaches. In May, 1944 when Hitler insisted that the 262 be modified to carry bombs, less than fifty had been assembled and all were in use in test programs. Due to the poor reliability (the Jumo 004s were lasting less than 10 hours before failure) none of the jet-powered aircraft would be suitable for any combat role for some time even reconnaissance. The many critics of the decision to use the Me-262 as a fighter-bomber must remember that in 1944 the plane stood as the last chance for an effective offensive air weapon for the Luftwaffe. Any blame for lack of impact of the German jets must rest squarely on the technology itself, rather than on the manner in which the handful of planes were utilized. It was a matter of too little, too late.

However, the engineering problems loomed large; the Me-262 had been designed as a fighter. Change-over to a “hit and run” Blitz bomber required many modifications. The original plane had two fuel tanks, each holding about 200 gallons of J2 fuel. Armament consisted of four 30mm cannon. That the Blitz was to carry two 550 lb. bombs required more fuel to give it an acceptable range. Two additional fuel tanks were fitted one 55 gallon vessel under the pilot’s seat and another 130 gallons in the fuselage to the rear of the main tank. This additional weight not only decreased the plane’s performance, it also resulted in troubles with the plane’s center of gravity. The added weight in the tail of the Blitz was balanced by the two center mounted bombs and two of the four cannon were taken away. The rear fuel tank was never to be filled unless the plane had a bomb load. When flying, the pilot had to be careful that the rear tank was emptied first. Mishandling of the fuel cocks, draining the forward tank first, and dropping bombs would cause the aircraft to rear up violently. Elevator control could not restore such an ill-weighted 262 and pilots who forgot these procedures in the heat of battle could easily lose their aircraft.

The conversion of KG 51 to the 262 was carried out at Lechfeld beginning on September 4th under command of Oberstleutnant Wolfgang Schenck. By late November, Schenk’s command possessed some thirty jets with 26 operational and 48 pilots in training. As a bomber, the 262 reflected its bastardized upbringing. Unlike conventional types, such as the Ju-88, the Blitz was not fitted with a downward facing bomb sight. It had a simple reflector reticle suitable for aiming cannon fire. With practice, pilots found they could reasonably hit sizeable targets, but precision bombing was out of the question. Dive bombing was also Verboten since a personal edict from Hitler himself forbade it along with any flying over enemy territory at less than 13,000 feet lest a 262 fall into enemy hands from AA fire. All this made for some very inaccurate bombing; members of KG 51 began to coyly refer to themselves as the “crop damage Geschwader.” If that was not depressing enough, an “Edelweiss” pilot had to worry about his back, since there was no armor behind the pilot’s head. This design flaw was found responsible for the death of a number of 262 bomber pilots who were killed before design changes went into effect in March, 1945. Some of the experienced Ju-88 and Me-410 pilots of the group had little confidence in the turbine engines and a perpetual fuel shortage made extensive training impossible. Some 65 tons of scarce petrol were needed to provide rudimentary training for a replacement pilot.

Then finally in September, Hitler relented on the employment of the 262 as a fighter, at least in a limited sense. During a Führer Konferenz on September 22nd, on the further reconsideration of this thorny matter, Hitler spelled out a convoluted policy that would allow for some jet fighter versions of the 262 so long as a commensurate number of jet bombers were provided:

“The Ar-234 will, with all possible dispatch continue to be turned out as a bomber in the greatest possible numbers. As it is possible to use this aircraft for the short range targets with three 1,100 pound bombs, and for long-range targets with one 1,100 pound bomb, under considerably more favorable general conditions than the Me-262 when used as a bomber, the Führer confirms his earlier promise that, for every single-battle worthy 234 accepted as a bomber, the General in charge of the fighters [Galland] will be allocated one battle-worthy 262 fighter.”

The direct result was that some forty Me-262s became available for the formation of the first combat jet fighter unit. The incipient command was organized under the legendary Austrian fighter ace, Maj. Walter Nowotny. When he took over the command, “Nowi” had some 250 combat victories and was perhaps the most famous of the Luftwaffe aces. The distinguished title for his unit would take its leader’s name Versuchskommando Nowotny. With tremendous expectation, his unit became operational as a 262 fighter training unit in October with some 23 jets, flying from airfields at Achmer and Hesepe. Not surprisingly, the new jet fighter pilots experienced a rash of technical problems, which led to a very low serviceability rate; on November 1st the unit had only nine of its jets serviceable. There were also questions regarding effective methods of attack. So fast were the machines that the 262 would close on enemy aircraft very rapidly with the target in range for only a fraction of a second. The obvious conclusion, to slow to strike their quarry, was no good. This would only sacrifice their speed advantage.

“Our strength lay in our enormous speed. The reaction propulsion system made us something like twice as fast as the enemy’s airscrew driven fighters. Moreover, the armament of the 262 with 43mm cannon was not only sensational; it was ideally suited to destroying the solid thick-skinned bombers. But the technology of this revolutionary machine also had its weakness that made high-level aerial combat and attacks on bomber formations problematical. Swinging into the target’s wake from above was out because of the danger of exceeding the maximum safe [airframe] speed, the aircraft having no brakes with which to check the rapid acceleration involved in such a maneuver. Frontal attack on collision course with the bombers a favorite method with the experts because the target was virtually defenseless and the crews of the Flying Fortresses were exposed to the hail of bullets was also out because the combined approach speeds made such an attack impossible. In practice we went back to the old, conventional attack from behind, approaching the bomber formation with of course a tremendous speed plus through the defensive fire of the rear gunners and letting off our cannon at short range. The Me-262 was a pretty sensitive and vulnerable piece of machinery, however, and our losses turned out to be higher than we had feared.”

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