The Vietnam air war changed dramatically on 24 July 1965 when a Soviet SA-2 [(Russian С-75, NATO reporting name SA-2 Guideline] missile downed an Air Force F-4 and damaged three others. Proving this shoot down was no fluke, two days later an SA-2 destroyed an American drone. US reconnaissance spotted construction of the first SAM site in early April and watched it and three other sites progress throughout the spring. But the decision makers would not permit the airmen to attack the missile sites, one of the many political restrictions on the air war. Secretary of Defense Robert McNamara argued that if the airmen attacked the SAM sites, they must also attack the MiG fields, which would be a major escalation of the air war. The leaders also feared that such attacks might cause Soviet casualties. Besides, one of McNamara's chief assistants, John T. McNaughton, believed that the SAMs only represented a bluff and would not be used.

The Soviet antiaircraft missile evolved from German World War II programs. The first Soviet SAM, the SA-1 [Soviet designation S-25 Berkut, NATO reporting name is SA-1 Guild], was inspired by the German Wasserfall [1] with ground (command) guidance. It became operational in early 1954. The West first saw its successor, the SA-2, in 1957. The Soviets designed this missile to defend against high-flying, essentially non-maneuvering, strategic bombers. The SA-2 measured 35 feet in length and weighed 4,875 pounds with its booster. It could carry a 288-pound warhead at Mach 3 .5 out to a slant range of 24-25 miles and was effective between 3,000 and 60,000 feet. The SA-2 first achieved prominence by knocking down an American U-2 over the Soviet Union in the spring of 1960 and downing another U-2 over Cuba in October 1962.

Despite knowledge of the missile since 1957, and its potential (similar to the Nike Ajax), the United States made only mixed progress with countermeasures. Tight budgets in the late 1950s hampered these efforts. Airmen assigned high priority to countermeasures against the SA-2 in budgets for fiscal years 1964 and 1965, but had nothing effective in hand when the need arose. As a result, in 1964, some airmen believed that aircraft could not operate in SAM protected areas. Although it is easy and partially correct to blame the tight funding, it is also true that the airmen underestimated the requirement for countermeasures. Although the US Air Force equipped strategic bombers with warning and jamming devices in the late 1950s, it did not similarly equip tactical fighters and bombers. Whatever the reason-money, obsession with nuclear weapons delivery, electrical power requirements, trust in fighter maneuverability and speed-the tactical air forces were unprepared for combat.

The potential SAM threat grew as the North Vietnamese incorporated more missiles into their inventory. North Vietnamese SAM battalions increased from one in 1965 to 25 the next year, to 30 in 1967, and to 35-40 in 1968. This growth in units permitted the North Vietnamese to increase their missile firings from 30 per month in the first 11 months of operation to 270 per month between July 1966 and October 1967. The latter month, with between 590 and 740 SAMs fired, was the peak month of firing until the Linebacker II operations of 1972. From October 1967 to the bombing halt on 1 April 1968, SAM firings averaged 220 per month. During this period, the American airmen observed 5,366-6,037 SAMs, which downed 115-128 aircraft.

Despite the increase in SAM firings, their direct effectiveness declined. In 1965 it took almost 18 SAMs to down each American aircraft, a figure that rose to 35 in 1966, to 57 in 1967, and to 107 in 1968. A number of factors contributed to this decline.

The airmen quickly learned that the SA-2 could be outmaneuvered. The Soviets designed the SA-2 to destroy highflying, non-maneuvering, strategic bombers; but until 1972 it engaged primarily low-flying, very maneuverable, tactical fighters. On clear days, alert airmen could spot SA-2 launches as the missile was large, described by most flyers as a flying telephone pole, and left a visible smoke trail.

The pilots would rapidly dive toward the missile, and when it changed direction to follow the aircraft, the pilot would pull up as abruptly and as sharply as possible. The SA-2 just could not follow such maneuvers. But such action required sufficient warning, proper timing, and, of course, nerve and skill. To give pilots adequate time to maneuver, procedures prohibited the pilots from flying too close to clouds between them and the ground. Later, the airmen received electronic devices that gave a visual and aural warning when a SAM radar was tracking (painting) an aircraft.

The American airmen also directly took on the missiles. On 27 July, 46 US Air Force fighter-bombers attacked two missile sites, met disaster, and according to a CIA report, hit the wrong targets. North Vietnamese gunners downed three aircraft while a midair collision accounted for two others. Nevertheless, the anti-SAM attacks continued. In the first nine months of 1966, the airmen launched 75 strikes against 60 sites and claimed to have destroyed 25 and damaged 25. Such attacks proved unprofitable because of the mobility of the SAMs-they could be relocated within hours.

One effort to counter North Vietnamese SAMs was standoff ECM: aircraft crammed with electronics gear that orbited a distance from the defenses and interfered with Communist radar and SAM signals. The Marines employed EF-1011s in this role between April 1965 and 1969. The Douglas Skyknight was ancient, having first flown in 1948 and seen action in the Korean War as a night fighter. It was joined in the ECM role in late 1965 by another Douglas product, the Skywarrior, which first flew in 1952. The Navy employed the Skywarrior as an electronic warfare aircraft designated as the EKA-3B. The Air Force adopted the Navy aircraft and also used it in the ECM role as the EB-66C, which carried a crew of seven, including four ECM operators in a crew compartment fitted in the bomb bay. Joined by other ECM versions of the B-66, it served throughout the war. However, the North Vietnamese moved their SAMs, forcing the EB-66 in turn to move away from North Vietnam to orbits over both Laos and the Gulf of Tonkin. In January 1968 a Vietnamese MiG downed an EB-66C (fig. 63). In late 1966 the Marines introduced the EA-6A in the jamming role.

A third American measure against the SAMs was codenamed Wild Weasel. The Air Force installed radar homing and warning (RHAW), electronics equipment that could detect SAM radar and indicate its location, into F-100Fs, the two-seat trainer version of its fighter-bomber. Wild Weasel I went into action in November 1965, flying with and guiding conventionally armed F-105s against SAM positions. These operations, known as Iron Hand (SAM suppression), preceded the main force by about five minutes, attacked and harassed the SAMs and thus permitted operations at 4,000-6,000 feet above the light flak into which the SAMs had forced the American aircraft.

In April and May of 1966 the American airmen first used the Navy's AGM-45A Shrike missiles. Now the anti-SAM crews had a standoff weapon that homed in on the SAM's radar signal. However, the Shrike had limited range and maneuverability and could be confused. These liabilities reduced the anti-radiation missile's (ARM) effectiveness as did Communist countermeasures. The North Vietnamese crews soon learned that by limiting emissions and coordinating several radars, they could still operate the SAMS and yet limit their vulnerability to the Wild Weasels. Just as the North Vietnamese used decoys to neutralize and ambush American air strikes, SAM operators sometimes turned on their radar to provoke an ARM launch and then turned it off before missile impact. The Shrike's kill rate declined from 28 percent of those launched by Air Force and Navy crews in 1966 to 18 percent in the first quarter of 1967. In the fall of 1967 SA-2 crews began using optical aiming, which rendered American ECM efforts useless; however, optical aiming required visual conditions, which also reduced SAM effectiveness. In March 1968 the Americans introduced the longer-range and more capable AGM-78 Standard ARM. Although it was constrained by reliability and size problems, nevertheless, the AGM-78 gave American airmen another weapon against the SAM.

In the summer of 1966 Wild Weasel III appeared in the form of the two-seat F-105 trainer, re-designated F-105G. Iron Hand operations were now easier as compatible aircraft were flying together. In late 1966 US airmen began using cluster bomb units (CBU-antipersonnel munitions) against North Vietnamese positions. But in the period following the 1968 bombing halt, 1969 until summer 1972, free-fall munitions were removed from Iron Hand aircraft, degrading their effectiveness. By then, however, the airmen had another weapon with which to combat the SAMs.

The Navy in mid-1966 and the US Air Force in October tested ECM pods carried beneath the fighters. A formation of fighters using the pods, the Navy's ALQ-51 and the Air Force's QRC-160-redesignated ALQ-71-seriously inhibited radar-directed defenses. The pods permitted operations between 10,000-17,000 feet, above the reach of light and medium flak. Put into service in January 1967, the pods further neutralized Communist defenses. But unfortunately for the airmen, the formation required for the best ECM results made the aircraft vulnerable to MiG attack. The various jamming devices forced the SAM operators to adopt a new procedure, track-on jamming. They fired the SA-2s at the jamming signal, but as it gave azimuth and not range information, it proved much less accurate than the normal method.

[1] The Wasserfall was most effective in providing a baseline for postwar US and Soviet SAM designs.

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The diminutive Me 163 Komet did not alter the war's history, but was an imaginative idea. Principal drawback to the concept was the dangerous fuel.

There can be little doubt that if the Messerschmitt Me 163 rocket-powered fighter had been available to the Luftwaffe in quantity a year earlier, the Allied daylight bombing programme would have proved even costlier than it was. With an extra year of development behind it, the Me 163's problems, particularly those concerned with handling its unstable mixture of rocket fuels, might well have been solved, but the whole programme was at the edge of a new technology range, and time was not on Germany's side.

Research had been proceeding in Germany into the possibility of rocket-powered aircraft since the 1920s and Dr Alexander Lippisch, who had been working on tailless sailplane designs, produced the DFS 194 glider in a basic layout which was to be developed into the Me 163. Lippisch and his team joined Messerschmitt in January 1939 and began work on adapting the DFS 194 airframe to take an 882-lb (400-kg) thrust Walter rocket motor. This motor had already flown in the experimental rocket-powered He 176, but that programme had been unsatisfactory. The DFS 194, on the other hand, reached a speed of 342 mph (550 km/h) during tests and this led to increased momentum in the programme, Messerschmitt receiving an order for six prototypes designated Me 163A.

The first prototype was tested originally as a glider, towed behind a Messerschmitt Bf 110, and its flying qualities were good, the few problems being easily ironed out. In the summer of 1941 two of the prototypes were taken to Peenemünde for powered trials with the new Walter HWK RII-203b rocket motor, which gave 1,653-lb (750-kg) thrust, and the Me 163 was soon attaining speeds of up to 550 mph (885 km/h). Since only a small amount of rocket fuel could be carried there was a danger of running out before higher speeds could be attained but on one occasion, after being towed to a height of 13,125 ft (4000 m), test pilot Heini Dittmar cast off, fired the engine and accelerated to reach the remarkable speed of 623.85 mph (1003.9 km/h) before suffering a loss of stability as a result of compressibility effects. This phenomenon was to become well known later as aircraft approached the speed of sound. Dittmar corrected the situation but a redesign of the wing was undertaken to combat this fault.

There was, in fact, more danger at this stage of the programme in the instability of the fuel, which was a mixture of 80 per cent hydrogen peroxide with oxyquinoline or phosphate (T-Stoff) and an aqueous solution of calcium permanganate (Z-Stoff). An imbalance of these fuels in the combustion chamber could cause an explosion and occasionally did; a replacement for Z-Stoff using a different catalyst (30 per cent hydrazine hydrate solution in methanol) was called C-Stoff and was developed for use in the Waiter RII-211 which, in its production form for the later Me 163B was the HWK 109-509A.

Since the Me 163 had to be as light as possible, in order to get the maximum performance from its very limited fuel load, the weight penalty of retractable landing gear was not acceptable. Thus, the take-off was made using a jettisonable two-wheel dolly, the aircraft landing on a retractable skid beneath the forward fuselage plus the tailwheel. The method caused problems, since take-offs had to be made directly into wind; if a concrete runway was to be used and there was a crosswind it was impossible to get airborne as the aircraft would not keep straight below the speed at which the rudder became operative. A subsequent modification to couple rudder control to rocket ignition partially cured this.

Following the six Me 163A prototypes, a preproduction series of 10 Me 163A-0 aircraft was built by Wolf Hirth, the sailplane company, and these were used as training gliders. However, considerable redesign took place before the operational Me 163B Komet (comet) flew. Six prototypes and 70 production models were ordered, but troubles with the new rocket motor held up the programme, and fuel consumption was almost double the calculated figure. Production was subcontracted to a number of component manufacturers and the parts were assembled in a Black Forest factory under the supervision of Klemm Technik GmbH, although this company had many problems since the sub-contractors were not accustomed to close-tolerance work.

First production deliveries of Me 163B-1a interceptors began in May 1944, and the type saw action for the first time on 28 July, when five Me 163s from l./JG 400, the first operational unit, ineffectively attacked a formation of Boeing B-17s near Merseburg. Their difficulties can be appreciated when it was realised that approaching the target at around 559 mph (900 km/h) when the bombers were travelling at 250 mph (402 km/h). The closing speed allowed the attacker only a three-second burst from a slow-firing cannon before he had to break away. Because of the poor results with the MK 108 cannon an alternative weapon had to be found.

One answer was certainly unusual; the SG 500 Jagdfaust consisted of five vertically mounted firing tubes in each wing root, each containing a 50-mm shell. The system fired in a salvo and was activated by the shadow of the target passing over a light cell (unfortunate if it happened to be your wingman) and the Me 163 merely had to fly at high speed beneath the bomber formation, when the armament was activated automatically. The Jagdfaust system was fitted to 12 Me 163Bs but, although these were not issued for operations, this unlikely weapon destroyed a B-17 on one occasion.

In 1944, to help convert the dwindling supply of pilots to the Me 163, a tandem trainer variant designated Me 163S was developed, an adaptation of the Me 163B with ammunition, T-Stoff tanks and other items removed to make way for the extra seat. The Me 163S was flown only as a glider and few were converted. Production of the Me 163B-1a ended in February 1945 after almost 400 of all variants had been built. Projected developments included the Me 163C and Me 163D; the former was a modification of the Me 163B with an auxiliary cruising chamber to improve endurance, a new centre-section and a more streamlined fuselage with a blister canopy. Three Me 163C-la aircraft were built, but only one was flown. The Me 163D was further refined and had retractable tricycle landing gear. One prototype was built and, since Junkers had been tasked with development and series production of this model, it was for a while known as the Ju 248 before reverting to a Messerschmitt designation as the Me 263. It did not enter production, the prototype being captured by the Russians who fitted it with new straight wings and modified tail surfaces, flying it in 1946 as the I-270(ZH), but it was soon abandoned.

Mention should be made of a licence-built version of the Me 163B, the Mitsubishi Ki-200 (J8M1), which was to be built in Japan with Mitsubishi and Yokosuka building the HWK 509A motor. Loss of the pattern aircraft on a ship en route to Japan left the Japanese with only an instruction manual, and it is to their credit that they began design of an airframe based on the Me 163B. The first aircraft flew in July 1945 but was destroyed when the motor failed. Several others were built but the programme was terminated by the end of the war.

Grigorovich M-5

This aircraft based on the seaplane carrier Imperator Alexander I. Black Sea Fleet.

Grigorovich M-9

Black Sea Fleet.

The other –than the Royal navy - great exponent of carrier aviation during World War I was the Imperial Russian Navy in the Black Sea. From early 1915 the Black Sea Fleet mounted a sustained interdiction campaign against Turkish sea communications. A particular target was the coal trade from Anatolia to Constantinople on which the Turkish- German fleet largely depended and that had to come by sea because there was no rail line and the road system was inadequate. According to Russian claims, their naval forces sank over 1,000 vessels during this campaign, in which the fleet’s aircraft carriers played a central role and must have been directly responsible for an appreciable percentage of these successes. On more than one occasion the battle cruiser Goeben and the light cruiser Breslau, units technically transferred to the Ottoman Navy from the German fleet but actually commanded and manned by Germans, that formed the modern heart of Turkish naval forces were incapable of putting to sea on operations for lack of fuel reserves.

The three carriers converted in early 1915 were fast enough to maintain formation with the older battleships that initially formed the core of the fleet and could keep up with even the new dreadnoughts that joined the fleet later. Consequently, there were few operations of any size in which the carriers were not tightly integrated and in several of those against the Anatolian and Bulgarian coastlines, the carriers formed the principal striking force with the battleships relegated to support and distant cover roles. Russian carriers used Curtiss flying boats initially, which eventually were supplanted by excellent indigenous Grigorivich boats. The carriers carried large numbers of aircraft for the period and their crews were highly trained, so their launch rates were impressive. One American observer timed a carrier launching seven aircraft in fifteen minutes, compared with the Royal Navy’s standard of twenty minutes to launch three aircraft (admittedly under North Sea conditions). After 1916, when Romania joined the war, the Black Sea Fleet’s aircraft carrier strength increased when one Romanian auxiliary, the Rominia, joined the fleet as a full-time carrier and was supplemented periodically by four other auxiliary cruisers embarking aircraft as operationally necessary. The carriers’ aircraft attacked Turkish and Bulgarian ports, their facilities, and ships at dock, conducted widespread reconnaissance missions, raided coastal shipping, bombed shore installations, spotted for the fleet’s guns, and provided cover for mine-laying operations and convoys.

By the end of World War I, naval aviation had secured for itself an important place in operations. For the most part, however, naval aircraft were shore based. While operational experience had confirmed the potential value of carrier-based aviation, the technical and functional details necessary for success remained immature. Major navies accepted that aircraft carriers were an essential feature of future fleets but the shape, size, arrangements, facilities, and equipment all were uncertain and still required much experiment and testing.

RUSSIA: ALMAZ (1915)

Builder: Baltic Works, St. Petersburg

Laid down: September 25, 1902. Launched: June 2, 1903. Commissioned: 1915

Displacement: 3,285 tons (normal)

Dimensions: 363’0” (oa) x 43’6” x 17’6” (mean)

Machinery: Vertical triple-expansion engines, Belleville boilers, 2 shafts, 7,500 ihp = 19 knots

Aircraft: 4

Armament: 7 x 4.7”, 4 x 12 pdr AA

Complement: 340

Design: Originally completed as an armed yacht rated as a third-class cruiser, the Almaz served as the viceregal yacht in the Far East and was the largest Russian survivor of the Battle of Tsushima (May 27-29, 1905). The Almaz was transferred to the Black Sea Fleet in 1911 and refitted as a seaplane carrier early in 1915. Seaplane handling platforms were fitted behind the mainmast and additional booms were rigged for lifting aircraft. Service: The Almaz formed part of the Hydro-Cruiser Division of the Black Sea Fleet from 1915 to 1917. As the fastest of the fleet’s seaplane carriers, it often undertook independent missions, including raids on Varna in Bulgaria in October 1915 and June 1916. After the popular revolution in 1917 the Almaz became a Bolshevik headquarters ship but was seized by French forces at Odessa in December 1918 and turned over to White Russian forces. It sailed to Algiers in 1920 with other White Russian vessels, was taken over there by the French in 1928, and scrapped in 1934.

RUSSIA: CONVERTED MERCHANTMEN (1915)

Builder:

Imperator Nikolai I: John Brown & Company Ltd., Clydebank

Imperator Alexandr I: William Denny & Brothers Ltd., Dumbarton

Displacement: 9,230–9,240 tons (normal)

Dimensions: 381’0” (oa) x 52’0” x 26’0” (mean)

Machinery: Vertical triple-expansion engines, 4 boilers, 2 shafts, 5,100 ihp = 13.5 knots

Aircraft: 8

Armament: 6 x 4.7”, 4 x 12 pdr AA

Complement: Unknown

Design: These two vessels were built as fast cargo liners for the Russian Steam Navigation Trading Company and completed in 1913 and 1914, respectively. They were requisitioned as naval auxiliaries after the outbreak of World War I and converted into seaplane carriers in early 1915. The conversion was minimal, involving fitting additional booms for aircraft handling and clearing after superstructure space to make room for aircraft stowage on the upper deck. Service: These vessels formed the core of the Black Sea Fleet’s Hydro- Cruiser Division and were very active against Turkish and Bulgarian coastal targets from March 1915 to February 1917. After the popular revolution they were renamed the Aviator and the Respublikanetz, but were laid up from April 1917 until they were taken over by French forces in December 1918. Both vessels entered French commercial service after World War I, serving with the Compagnie des Messageries Maritimes as the Pierre Loti and the Lamartine. The Pierre Loti was wrecked in the Gabon River estuary in 1943 and the Lamartine, by then renamed the Khaidinh, was sunk by United States Navy aircraft in Along Bay in 1942.