Saturday, 31 October 2015

Messerschmitt Me-262 Schwalbe / Sturmvogel. Part 3. Operational history. Luis German Dzib -Compiler-


Major Walter Novotny

On April 1944, Erprobungskommando 262 was formed at Lechfeld just south of Augsburg, as a test unit (Jäger Erprobungskommando Thierfelder, commanded by Hauptmann Werner Thierfelder) (16) (17) to introduce the 262 into service and train a corps of pilots to fly it. On 26 July 1944, Leutnant Alfred Schreiber with the 262 A-1a W.Nr. 130 017 damaged a Mosquito reconnaissance aircraft of No. 540 Squadron RAF PR Squadron, which was allegedly lost in a crash upon landing at an air base in Italy. (18) Other sources state the aircraft was damaged during evasive manoeuvres and escaped. (19) It was the first victory for a turbojet fighter aircraft in aviation history. (20) Major Walter Nowotny was assigned as commander after the death of Thierfelder in July 1944, and the unit redesignated Kommando Nowotny. Essentially a trials and development unit, it holds the distinction of having mounted the world's first jet fighter operations. Trials continued slowly, with initial operational missions against the Allies in August 1944 allegedly downing 19 Allied aircraft for six Me 262s lost, although these claims have never been verified by cross-checking with USAAF records. The RAF Museum holds no intelligence reports of RAF aircraft engaging in combat with Me 262s in August, although there is a report of an unarmed encounter between an Me 262 and a Mosquito. (21)

Despite orders to stay grounded, Nowotny chose to fly a mission against an enemy bomber formation flying some 30,000 feet above, on 8 November 1944. He claimed two P-51Ds destroyed before suffering engine failure at high altitude. (22) Then, while diving and trying desperately to restart his engines, he was attacked by other Mustangs, and forced to bail out. Historians Morgan and Weal proposed Nowotny's victor was P-51D pilot Lt. Robert W. Stevens of the 364th Fighter Group. (23) The exact circumstances surrounding the death of Walter Nowotny remain uncertain to this day. It is also possible he was hit by "friendly" flak. (23) (24) The Kommando was then withdrawn for further training and a revision of combat tactics to optimise the 262's strengths. Me 262 A-1a, W.Nr. 112372, on display at RAF Cosford, 2002. Some Me 262 A-1a aircraft, like the A-2a bomber variant, attached additional hardpoints, such as bomb racks, under the nose of the aircraft. (25) This was accomplished by having two slots near the ejector chutes of the MK 108 cannons where bomb racks could be attached. W.Nr. 112372, on display at the Royal Air Museum London, is a surviving example of this type.



By January 1945, Jagdgeschwader 7 (JG 7) had been formed as a pure jet fighter wing, although it was several weeks before it was operational. In the meantime, a bomber unit—I Gruppe, Kampfgeschwader 54 (KG 54)—had re-equipped with the Me 262 A-2a fighter-bomber for use in a ground-attack role. However, the unit lost 12 jets in action in two weeks for minimal returns. Jagdverband 44 (JV 44) was another Me 262 fighter unit, of Staffel (squadron) size given the low numbers of available personnel, formed in February 1945 by Lieutenant General Adolf Galland, who had recently been dismissed as Inspector of Fighters. Galland was able to draw into the unit many of the most experienced and decorated Luftwaffe fighter pilots from other units grounded by lack of fuel. (26)
During March, Me 262 fighter units were able, for the first time, to mount large-scale attacks on Allied bomber formations. On 18 March 1945, 37 Me 262s of JG 7 intercepted a force of 1,221 bombers and 632 escorting fighters. They shot down 12 bombers and one fighter for the loss of three Me 262s. Although a 4:1 ratio was exactly what the Luftwaffe would have needed to make an impact on the war, the absolute scale of their success was minor, as it represented only one per cent of the attacking force. In 1943 and early 1944, regardless of the presence of the small numbers of Me 262s, the USAAF was able to keep up offensive operations at loss ratios of roughly 5%. 


Me 262B-1a/U1 night fighter, Wrknr. 110306, with Neptun radar antenna on the nose and second seat for a radar operator. This airframe was surrendered to the RAF at Schleswig in May 1945 and taken to the UK for testing
Several two-seat trainer variants of the Me 262, the Me 262 B-1a, had been adapted through the Umrüst-Bausatz 1 factory refit package as night fighters, complete with on-board FuG 218 Neptun high-VHF band radar, using Hirschgeweih ("stag's antlers") antennae with a set of shorter dipole elements than the Lichtenstein SN-2 had used, as the B-1a/U1 version. Serving with 10 Staffel, Nachtjagdgeschwader 11, near Berlin, these few aircraft (alongside several single-seat examples) accounted for most of the 13 Mosquitoes lost over Berlin in the first three months of 1945. However, actual intercepts were generally or entirely made using Wilde Sau methods, rather than AI radar-controlled interception. As the two-seat trainer was largely unavailable, many pilots made their first jet flight in a single-seater without an instructor.



Despite its deficiencies, the Me 262 clearly signaled the beginning of the end of piston-engined aircraft as effective fighting machines. Once airborne, it could accelerate to speeds over 850 km/h (530 mph), about 150 km/h (93 mph)faster than any Allied fighter operational in the European Theater of Operations. The Me 262's top ace was probably Hauptmann Franz Schall with 17 kills, which included six four-engine bombers and 10 P-51 Mustang fighters, although night fighter ace Oberleutnant Kurt Welter claimed 25 Mosquitos and two four-engine bombers shot down by night and two further Mosquitos by day flying the Me 262. Most of Welter's claimed night kills were achieved in standard radar-less aircraft, even though Welter had tested a prototype Me 262 fitted with FuG 218Neptun radar. Another candidate for top ace on the aircraft was Oberstleutnant Heinrich Bär, who claimed 16 enemy aircraft while flying the Me 262.
ith little risk of interception. When they were about 1.5 km astern (0.93 mi) and 450 metres (1,480 ft) below the bombers, they pulled up sharply to reduce their excess speed. On levelling off, they were 1,000 m astern (1,100 yd) and overtaking the bombers at about 150 km/h (93 mph), well placed to attack them. (27)
Since the 30mm MK 108 cannon's short barrels and low muzzle velocity of 540 m/s (1,800 ft/s) rendered it inaccurate beyond 600 m (660 yd), coupled with the jet's velocity, which required breaking off at 200 m (220 yd) to avoid colliding with the target, Me 262 pilots normally commenced firing at 500 m (550 yd). (28) Turret gunners of Allied bomber aircraft found that their manned electrically-powered gun turrets had problems tracking the jets. Target acquisition was difficult because the jets closed into firing range quickly and remained in firing position only briefly, using their standard attack profile, which proved more effective.




Anti-bomber tactics

 
B-17G 44-6387 of the 815th Bombardment Squadron was lost on the mission to Ruhland, Germany on 22 March 1945, it was hit first by Flak, then finished off by an Me 262. Eight of the crew survived as POWs
The Me 262 was so fast that German pilots needed new tactics to attack Allied bombers. In the head-on attack, the closing speed, of about 320 m per second (350 yd), was too high for accurate shooting. Even from astern, the closing speed was too great to use the short-ranged 30 mm cannon to maximum effect. Therefore, a roller-coaster attack was devised. The 262s approached from astern and about 1,800 m higher (5,900 ft) than the bombers. From about 5 km behind (3.1 mi), they went into a shallow dive that took them through the escort fighter with little risk of interception. When they were about 1.5 km astern (0.93 mi) and 450 metres (1,480 ft) below the bombers, they pulled up sharply to reduce their excess speed. On levelling off, they were 1,000 m astern (1,100 yd) and overtaking the bombers at about 150 km/h (93 mph), well placed to attack them. (27)



Since the 30mm MK 108 cannon's short barrels and low muzzle velocity of 540 m/s (1,800 ft/s) rendered it inaccurate beyond 600 m (660 yd), coupled with the jet's velocity, which required breaking off at 200 m (220 yd) to avoid colliding with the target, Me 262 pilots normally commenced firing at 500 m (550 yd). (28) Turret gunners of Allied bomber aircraft found that their manned electrically-powered gun turrets had problems tracking the jets. Target acquisition was difficult because the jets closed into firing range quickly and remained in firing position only briefly, using their standard attack profile, which proved more effective.
Me 262 with R4M underwing rockets on display at the Technikmuseum Speyer, Germany



 

Captain Eric Brown, Chief Naval Test Pilot and C.O. Captured Enemy Aircraft Flight Royal Aircraft Establishment, who tested the Me 262 noted: "This was a Blitzkrieg aircraft. You whack in at your bomber. It was never meant to be a dogfighter, it was meant to be a destroyer of bombers... The great problem with it was it did not have dive brakes. For example, if you want to fight and destroy a B-17, you come in on a dive. The 30mm cannon were not so accurate beyond 600 meters. So you normally came in at 600 yards and would open fire on your B-17. And your closing speed was still high and since you had to break away at 200 meters to avoid a collision, you only had two seconds firing time. Now, in two seconds, you can't sight. You can fire randomly and hope for the best. If you want to sight and fire, you need to double that time to four seconds. And with dive brakes, you could have done that." (28)


Eventually, German pilots developed new combat tactics to counter Allied bombers' defenses. Me 262s, equipped with R4M rockets, approached from the side of a bomber formation, where their silhouettes were widest, and while still out of range of the bombers' machine guns, fired a salvo of rockets with strongly brisant Hexogen-filled warheads, exactly the same explosive in the shells fired by the Me 262A's quartet of MK 108 cannon. One or two of these rockets could down even the famously rugged B-17 Flying Fortress, (29) from the "metal-shattering" brisant effect of the R4M rockets' explosive warheads, weighing only some 520 grams (17.6 ounces) per projectile out of a total launch weight of 4 kg (8.8 pounds) apiece.
Though this tactic was effective, it came too late to have a real effect on the war, and only small numbers of Me 262s were equipped with the rocket packs. (30) Most of those so equipped were Me 262A-1as, members of Jagdgeschwader 7. (31) This method of attacking bombers became the standard, and mass deployment of Ruhrstahl X-4 guided missiles was cancelled. Some nicknamed this tactic the Luftwaffe's Wolf Pack, as the fighters often made runs in groups of two or three, fired their rockets, then returned to base. On 1 September 1944, USAAF General Carl Spaatz expressed the fear that if greater numbers of German jets appeared, they could inflict losses heavy enough to force cancellation of the Allied bombing offensive by daylight.

Counter-jet tactics

The Me 262 was difficult for its opponents to counter because its high speed and rate of climb made it extremely hard to intercept. As with all other early jets, the Me 262's engines did not provide a lot of thrust at low air speeds (a key criterion for good turn performance at low speeds), and throttle response was slow. Another disadvantage all early jet engines shared was a relatively high risk of flameout if the pilot used the throttle too aggressively (as is common in a dogfight). Pilots were instructed to operate the throttle gently and avoid quick changes. German engineers introduced an automatic throttle regulator later in the war but it only partly alleviated the problem. On the plus side, thrust at high speed was much greater than on propeller-driven aircraft.
The plane had, by contemporary standards, quite a high wing loading (294.0 kg/m2, 60.2 lbs/ft2) and its turn radius at low speeds was therefore correspondingly wide. This, coupled with the low thrust at slow speeds and high chance of a flameout if the throttle was worked too aggressively, resulted in Me 262 pilots being told to avoid low speed dogfights with the Allied piston-engine fighters. The high speed of the Me 262 also presented problems when engaging enemy aircraft, the high-speed convergence allowing Me 262 pilots little time to line up their targets or acquire the appropriate amount of deflection. This problem faces any aircraft that approaches another from behind at much higher speed, as the slower aircraft in front can always pull a tighter turn, forcing the faster aircraft to overshoot. The Me 262 faced this problem frequently as its cruising speed alone was up to 200 km/h (120 mph) faster than that of any piston-engine fighter of the period.
"I passed one that looked as if it was hanging motionless in the air (I am too fast!). The one above me went into a steep right-hand turn, his pale blue underside standing out against the purple sky. Another banked right in front of the Me's nose. Violent jolt as I flew through his airscrew eddies. Maybe a wing's length away. That one in the gentle left-hand curve! Swing her round. I was coming from underneath, eye glued to the sight (pull her tighter!). A throbbing in the wings as my cannon pounded briefly. Missed him. Way behind his tail. It was exasperating. I would never be able to shoot one down like this. They were like a sack of fleas. A prick of doubt: is this really such a good fighter? Could one in fact, successfully attack a group of erratically banking fighters with the Me 262?"
Johannes Steinhoff, Luftwaffe fighter ace. (32)

Luftwaffe pilots eventually learned how to handle the Me 262's higher speed, and the Me 262 soon proved a formidable air superiority fighter, with pilots such as Franz Schall managing to shoot down 12 enemy fighters in the Me 262, 10 of them American P-51 Mustangs. Other notable Me 262 aces included Georg-Peter Eder, also with 12 enemy fighters to his credit (including nine P-51s), Erich Rudorffer also with 12 enemy fighters to his credit, Walther Dahl with 11 (including three Lavochkin La-7s and six P-51s) and Heinz-Helmut Baudach with six (including one Spitfire and two P-51s) amongst many others.


Me-262 being shot down. Note jettisoned
 canopy and empty cockpit. As seen from  
USAAF P-51 Mustang gun camera
Pilots soon learned that the Me 262 was quite maneuverable, despite its high wing loading and lack of low-speed thrust, especially if attention was drawn to its effective maneuvering speeds. The controls were light and effective right up to the maximum permissible speed and perfectly harmonized. The inclusion of full span automatic leading-edge slats, something of a "tradition" on Messerschmitt fighters dating back to the original Bf 109's outer wing slots of a similar type, helped increase the overall lift produced by the wing by as much as 35% in tight turns or at low speeds, greatly improving the aircraft's turn performance as well as its landing and take-off characteristics. (33) And as many pilots soon found out, the Me 262's clean design also meant that it, like all jets, held its speed in tight turns much better than conventional propeller-driven fighters, which was a great potential advantage in a dogfight as it meant better energy retention in maneuvers. (34) Luftwaffe test pilot and flight instructor Hans Fey stated, "The 262 will turn much better at high than at slow speeds and, due to its clean design, will keep its speed in tight turns much longer than conventional type aircraft." (35) 
Too fast to catch for the escorting Allied fighters, the Me 262s were almost impossible to head off.  As a result, Me 262 pilots were relatively safe from the Allied fighters, as long as they did not allow themselves to get drawn into low-speed turning contests and saved their maneuvering for higher speeds. Combating the Allied fighters could be effectively done the same way as the U.S. fighters fought the more nimble, but slower, Japanese fighters in the Pacific.
Allied pilots soon found that the only reliable way to destroy the jets, as with the even faster Me 163 Komet rocket fighters, was to attack them on the ground or during takeoff or landing. Luftwaffe airfields identified as jet bases were frequently bombed by medium bombers, and Allied fighters patrolled over the fields to attack jets trying to land. The Luftwaffe countered by installing extensive flak alleys of anti-aircraft guns along the approach lines to protect the Me 262s from the ground—and by providing top cover during the jets' takeoff and landing with the most advanced Luftwaffe single-engined fighters, the Focke-Wulf Fw 190D and (just becoming available in 1945) Focke-Wulf Ta 152H. (36) Nevertheless, in March–April 1945, Allied fighter patrol patterns over Me 262 airfields resulted in numerous jet losses.
The British Hawker Tempest scored a number of kills against the new German jets, including the Messerschmitt Me 262. Hubert Lange, a Me 262 pilot, said: "the Messerschmitt Me 262's most dangerous opponent was the British Hawker Tempest — extremely fast at low altitudes, highly manoeuvrable and heavily armed." (37) Some were destroyed with a tactic known to the Tempest 135 Wing as the "Rat Scramble": Tempests on immediate alert took off when an Me 262 was reported airborne. They did not intercept the jet, but instead flew towards the Me 262 and Ar 234 base at Rheine-Hopsten. (38) The aim was to attack jets on their landing.

Me-262 in combat



With Allied aircraft operating in ever-increasing numbers over the Reich, operational evaluation of the Me-262 had been difficult, to say the least. Trying to work the bugs out of an aircraft while dodging enemy fighters was far from an ideal situation for flight test.
The evaluation did show that the Me-262 was not only fast but was responsive and docile. However, it did tend to "snake" at high speeds, reducing its accuracy as a gun platform, and it was underpowered, with a long take-off run. Losing an engine was very dangerous, since the Me-262 could barely stay in the air on one engine; if an engine were lost below 290 KPH (180 MPH), the aircraft would usually be lost as well. The engines were also not very reliable, being prone to flameouts and burnouts.
The first documented air combat involving an Me-262 took place on 25 July 1944, when a Schwalbe pounced on an RAF Mosquito that escaped only by the hardest. One Me-262 was shot down near Brussels on 28 August by a pair of USAAF P-47 Thunderbolts, the first Me-262 to be lost to direct enemy action. An operational fighter squadron, the "Kommando Nowotny", was established out of Erprobungskommando 262 in September 1944, under experienced ace Major Walter Nowotny. Kommando Nowotny became operational on 3 October.

The Me-262 was highly vulnerable on takeoff and landing, since the Jumo engines took a long time to throttle up; since the engines tended to set asphalt runways on fire, the Me-262 was restricted to operations at airfields with concrete runways, which were more easily targeted by the Allies than dispersed dirt airfields. On 7 October two were shot down on takeoff by Lieutenant Urban L. Drew of the USAAF, flying a P-51 Mustang. The Luftwaffe eventually assigned FW-190s, when they were available and had fuel, to fly air patrols around the air bases to protect the Me-262s, and the airfields were ringed by heavy flak defenses. The flak installations were a mixed blessing, however, since they were often staffed by poorly-trained and nervous troops who were just as likely to fire on friends as foes.
Many of the Me-262 pilots were also inexperienced, and flying an aircraft with performance greater than any operated before would have been a challenge to more professional aviators. Hitting Allied bombers while streaking through a formation at high speed was difficult, and if an Me-262 pilot slowed down to take more careful aim, he became a good target for the bombers' defensive fire and escorting Allied fighters.
Attrition was high. Nowotny himself was killed in action on 8 November 1944 when his and two other Me-262s were shot down. The few survivors were incorporated into a full Me-262 group, "III/JG7", which achieved a number of kills in the months remaining of the war. Two other groups, "I/JG7" and "II/JG7" were never fully brought up to strength. Four more bomber units were formed but saw little action.
Faced with overwhelming Allied strength and extreme logistical problems, particularly fuel shortages, Me-262 operations during those months were intermittent. An elite unit, "JV-44", was formed up under Adolf Galland, and racked up a number of kills before hostilities ended.

Many of these kills were achieved with the new R4M 55 millimeter (2.2 inch) folding fin rockets. An Me-262 could carry a total of 24 such weapons on wooden racks, one under each wing, and if fired into a bomber formation the rockets could have a devastating effect on anything they hit. Schwalbes configured to carry the R4M were given the designation "Me-262A-1b". A ground-attack version of the R4M rocket was also designed and might have helped turn the Me-262 into an effective "Jabo" aircraft, much like the RAF's rocket-firing Typhoons or "Rockoons", but it does not appear the Luftwaffe ever used the Me-262 in this way.