Generally speaking, the Luftwaffe has had little success in keeping combat design secrets from the Allies. Where American, British and Russian intelligence have spent months in building files on Japanese aircraft, performance data and structural details on the Focke-Wulf 190, on the new Messerschmitt troop-carrier, and on every development in the Dornier 215 line were available to Allied forces almost as soon as the planes went into service. There is, however, one exception to this rule. For more than a year, the Messerschmitt 210 has been hailed as the greatest of the late additions to Nazi air strength. Beyond the fact that it was destroying British and American aircraft with alarming success, little information on the German ship has been available. That such data is now in Allied hands is encouraging, be- cause it indicates that enough of these twin-engine fighter-bombers have been captured by the Allies to make full information no longer secret.
Fundamentally, the Messerschmitt 210 is hardly unique. In exterior line and tactical purpose it follows closely the characteristics of the highly-successful Mosquito series. Further than that, the Messerschmitt incorporates so many divergent design philosophies as to make comparison with any one existing type impractical. But like all of the twin-engine types now appearing in combat zones, it serves adequately with slight modifications as long-range fighter escorting heavy bombers, as a dive bomber, and as low-level attack plane.
Viewed from a structural standpoint, the 210 follows closely the pattern of other planes in the Messerschmitt line, although the wing is built as a single unit passing directly through the fuselage. Otherwise, it bears close resemblance to this manufacturer's regular output. The wing, a single-spar design, is combined with a fuselage built in halves and joined along the top and bottom. Top hat section stringers are used and the 210s so far captured have been powered by two DB-601F liquid-cooled engines. These power plants differ from that installed in the Messerschmitt 109F only in having special cooling ducts. Fitted on each side of the nacelles, these ducts direct cool air over the exhaust stubs and into the wells in which spark plugs are mounted. The basic armament of the 210 is also in line with existing Nazi tenets, with a pair of fixed 7.9-mm machine guns and two fixed Mauser 20s fitted in the nose.
It is the additional armament which constitutes the principal interest point in the Me-210. These are 13-mm guns, mounted in streamlined metal blisters on either side of the fuselage. Fired by remote control, they give the rear gunner a blazing firepower with which to oppose attackers. Like all German aircraft, the Messerschmitt 210 carries considerable ammunition more, perhaps, than some American designers of cannon-carrying planes like to admit. Bombs are stowed internally directly beneath the nose guns, and bomb loads vary in type but usually total 2,200 pounds.
With some optimistic observers insisting that German workmanship has deteriorated in recent months, a study of the Messerschmitt structure is especially informative. If it proves anything, it indicates that Teutonic craftsmanship and ingenuity has suffered little, if at all, through the strain placed on resources and factories by more than forty months of war. The wing spar booms are constructed from L-section aluminum alloy extrusions. Mounted back to back, these sections form a rugged T with webbing between, further strengthened by use of a flat extrusion on top. The entire assembly is riveted together. Spar plates at the juncture of the outer wing and center section are fitted with self-aligning bushings and a central shear attachment between upper and lower joints is similarly bushed. A further attachment of the outer wing to the center section is made at the leading edge by means of a very large ball joint, supplemented by wing reinforcement in the form of an additional rib and thick gauge metal.
End ribs are pressings with conveniently spaced corrugations strengthening the webbing. Although the metal skin is flush-riveted, the ailerons are fabric-covered in the same manner as the elevators included with the stressed-skin fin, stabilizers and rudder. Two sets of Venetian blind diving brakes are used on the 210, with three metal slats comprising the upper surface brake and four slats used on the lower surface. These retractable slats are, in themselves, as interesting as the plane as a whole. Hydraulically operated with a parallel motion, they fit flush with the wing profile to reduce drag to a minimum while gaining some immunity from shrapnel damage which has crippled many Stukas. Flexible self-sealing fuel tanks and oil reservoirs are fitted into the wings and the 210 carries approximately 550 gallons of gasoline. These tanks are apparently the closest approach to crash-proof equipment currently in service. The fiber sheet, formerly used on such Nazi tanks, has been replaced by the flexible skin made of a rubber compound approximately 3/8" thick, with reinforcements giving greater thickness at the outer and longitudinal seams. The resulting tank is, of course, considerably heavier than standard leak-proof tanks. Housed within the wing and center section, these tanks are slung on the upper surface by means of two attachments. A circular bracket on the tank is fitted with four raised lugs which are, in turn, bolted to the top wing skin. Five additional metal rings, of smaller diameter, have a central bolt attachment from the tank to the skin to prevent sagging as fuel is consumed in flight. There is no apparent means for jettisoning the tanks.
German practice is completely reversed in the 210's unique engine mounting illustrated in an accompanying sketch. Main supporting members are welded steel box girders in compression, with standard shock-absorber mount held in position by oversize circlips at the two pickup points on the engine. Extending to a ball joint at the firewall, they are joined by a diagonal tubular support running at a 45° angle from the top of the bulkhead. The small number of structural members is undoubtedly aiding high-speed production of the Messerschmitt 210.
Remote control of aircraft guns is not new in theory, nor in limited practice. But the Germans have made the arrangement a tactical weapon in the Me-210 and have apparently sacrificed little flight performance despite the weight of their excellent remote gun arrangement. Sighted and remotely fired by the rear gunner, these 13-mm guns can be moved approximately 35° above or below center in astral and 39° in azimuth. By moving his control grip vertically or sideways, the gunner motivates Servo units which activate a 1.5-hp electric motor driving a rotary drum which moves the gun in astral or azimuth. A reflector sight is fitted for each gun and the guns themselves are mounted at the extreme ends of the drum across the fuselage. Well conceived, beautifully executed, the arrangement is extremely complicated and dependence on a powerful battery necessary for movement of the geared drums must add considerably to the unit's weight. Thus, it hardly seems to match the efficiency of several British and American powered turrets. The balance of the 210's armament follows closely the mounting principles current in all belligerent nations. Blast tubes are fitted to the 20-mm Mauser cannon and the 7.9-mm machine guns to assist in cooling, with those on the machine guns extending the full barrel length while those on the cannons terminate directly behind the muzzle. Bombs are carried well forward in the fuselage, directly beneath the forward gun mounts.
Armor protection, for crew and vital parts, is profuse and widely distributed, contributing more than 900 pounds to the total empty weight of the plane. Pilot armor is mounted under and back of the seat while the rear gunner is protected by a bullet-proof glass panel, more than two inches thick, which surmounts an armor plate apron. Additional armor plate covers all vulnerable engine parts as well as the cooling system.
Generally good in design, particularly efficient as a dive bomber, the Messerschmitt 210 outclasses British and American designs of this type on some points but lacks the performance of our twin-engine types when used as a fighter. It has a top speed at 18,000' estimated at 370 mph, weighs approximately 21,350 lb fully loaded. It has a wing span of 53' 9" and measures 40' 3" in overall length.
This article was originally published in the April, 1943, issue of Air News magazine, vol 4, no 4, pp 7-9, 56.
Air News was printed on newsprint in a 9½" × 10½" format.
The original article includes an artist's impression, a 3-view line drawing and 5 diagrams of functional systems or installations.
Rendering is credited to British Combine, signed by Robert Lindgren; diagrams credited to Flight.