The First Production ECM Pod for Jet Aircraft: Tee Town

In the late 1950s Soviet defenses against the bombers of the Strategic Air Command were improving by leaps and bounds as more capable fighters, radars and surface-to-air missiles were deployed not just on the periphery of the Soviet Union but also around key cities and industrial centers like Moscow and Leningrad. At the time, SAC's bomber force consisted of 100 Boeing B-52 Stratofortresses, over 1,000 Boeing B-47 Stratojets, and 200 Convair B-36s that were gradually being phased out. As the tip of SAC's spear, the B-52s had a comprehensive electronic countermeasures suite as well as an onboard electronic warfare officer who could constantly reconfigure the jammers to meet the threats.

The B-36s being piston-driven (despite the addition of four jet engines) was soon to be phased out, so there was no need to upgrade to the ECM systems. But the B-47 made up three-quarters of SAC's offensive striking force and unlike the B-52, didn't have the space or power for additional jamming systems to put it on par with the Stratofortresses.

The solution came with a $2.5 million contract code named Tee Town. Carried out in 1958 to 1959 with the assistance of Douglas Aircraft's Tulsa Division, Tee Town consisted of two 14-foot long pods mounted on cantilevered pylons attached to the bomb bay doors. Each pod carried four ALT-6B jammers on the lower half of the pod and covered by a fiberglass dielectric fairing. Ram air was ducted around each of the jammers for cooling and Douglas added upgraded electrical generators on the Tee Town aircraft to handle the increased electrical demand.

Tee Town was planned as an interim measure pending deployment of the specialized Phase V jamming escort version of the B-47 that would accompany strike cells of nuclear-armed Stratojets. Sixty B-47s were modified to carry the Tee Town pods and were assigned to the 303rd Bomb Wing at Davis-Monthan AFB in Arizona and the 509th Bomb Wing at Pease AFB in New Hampshire.

Although only 120 of the Tee Town pods were built, it marked a historical point as the world's first electronic warfare jamming pod designed for high speed aircraft to go into production.

Source: The History of U.S. Electronic Warfare, Volume II- The Renaissance Years, 1946-1964 by Alfred Price. The Association of Old Crows/Port City Press, 1989, p191-192.

In electronic warfare, often the most effective countermeasure to the enemy's attempts at jamming and deception is a well-trained radio or radar operator. Throughout the 1950s as electronic warfare took on added importance during the Cold War, it was difficult at best to get training time on operational ECM systems. Most operational systems were strictly allocated to front-line units and often were scarce as new systems were constantly being developed and entered into service to meet new Soviet threats. As most operational systems were designed specifically to counter Soviet systems, those operational units couldn't be tested or trained since there were no Soviet examples available for training purposes- obviously!

Some units elected to train against US systems (often the service branches might train against each other), but an operational EW system had to be modified to work against US systems for the duration of the exercise and it was often said the surest way to make an electronic warfare system unserviceable was to take it out of the aircraft and put it back in again.

Peacetime exercises often were of limited value due to interservice rivalries. During one exercise in the 1950s in which SAC's B-47 Stratojets were to attempt to penetrate the US air defenses of New England (made up of Army missile units and USAF Air Defense Command interceptor aircraft), the Stratojet crews were instructed to "go easy" on the ADC fighters and "plaster" the Army missile units. The proper training of operators to deal with enemy electronic warfare and countermeasures requires that the students undergo a series of increasingly difficult scenarios rather than overwhelm them outright.

The US Navy was the first to recognize this need and in 1957 created a unit dedicated to creating a realistic ECM environment for training the fleet. Four Grumman TF-1 (redesignated C-1A after 1962) Traders that were usually used for carrier on-board delivery missions were modified into airborne jamming simulators. With a crew of five that included two pilots and three ECM operators, the TF-1s were crammed full of electronic warfare equipment as well as equipment for analyzing and grading the responses of the units being trained.

The weight of all the equipment was so great that the TF-1Q, as it was designated, was too heavy to operate safely from carriers and its range suffered as well. But this was of little issue to the Navy as the TF-1Qs were to be shore based and train fleet personnel in US waters. The first unit was VAW-35 based in NAS North Island in San Diego before the aircraft were split up with two TF-1Qs based at NAS Alameda with VAW-13 to work with the Pacific Fleet and two TF-1Qs were based at NAS Quonset Point, Rhode Island with VAW-33 to work with the Atlantic Fleet. In the years that followed, the TF-1Qs (redesignated EC-1A after 1962) were worked hard acting as enemy "Red" forces for carrier battle groups preparing to deploy overseas.

The value provided by a dedicated electronic aggressor force was such that the Navy in 1969 established the Fleet Electronic Warfare Support Group made up of the squadrons VAQ-34 "Flashbacks" and VAQ-33 "Firebirds" by which time the FEWSG operated a variety of aircraft as well as civilian contractor aircraft to provide the most realistic training environment for the Navy, a mission that continues to this day.

Source: The History of U.S. Electronic Warfare, Volume II- The Renaissance Years, 1946-1964 by Alfred Price. The Association of Old Crows/Port City Press, 1989, p203-205.

When the Tupolev Tu-16 Badger and Myasishchev M-4 Bison were revealed to the public at the 1954 May Day Parade in Moscow's Red Square, the United States realized that the Russians now had high-performance jet bombers capable of delivering atomic bombs to US cities. The USAF, via the Rome Air Development Center in New York, had the previous year started a program with General Electric on using jammers to modify the radar echoes of coastlines, rivers and cities to confuse the mapping radars used on strategic bombers. With the Badger and Bison unveiled in 1954, the work with GE took on added urgency.

In cooperation with the Strategic Air Command, GE engineers ran a test called the "Baltimore Project" to determine the nature of radar returns coming from a large city. A SAC Boeing B-29 with an APS-23 bombing/navigation radar was fitted with a selectable attenuator and the B-29 would overfly Baltimore, Maryland at different directions and with the attenuator set at different levels. This way they could filter out all but the strongest radar echoes. Combined with ground surveys of the areas of the city that were the most radar reflective, it was determined that oil storage tank farms were the most reflective followed by railroad yards and then factory complexes.

The engineers at GE then came up with what was called the Distributed Area Jammer (DAJ) which was a simple repeater that fit into a cylinder six inches across and 14 inches long. Twenty prototype DAJs were built which were installed on telephone poles and powered by the local power grid. They estimated that each DAJ unit would cost about a thousand dollars.

Tests using the prototype DAJs were conducted on Cape Cod, Massachusetts to see if they could use the jammers to alter the radar echoes of the coastline, which they found was easily accomplished by spacing the DAJs in a grid pattern a mile apart from the next DAJ. It was also found that clustering the DAJs close together produced a false radar echo that looked like a major city.

As preparations for production began with the intent of protecting a limited set of potential targets, Congress got wind of the DAJ project and each senator and representative demanded that their constituents be protected with a DAJ network. As a result, the cost spiraled upward as the USAF found that the number of DAJs needed just to protect the Eastern Seaboard alone made the cost unfeasible. As a result, the DAJ program was cancelled and it never went into production.

Source: The History of U.S. Electronic Warfare, Volume II- The Renaissance Years, 1946-1964 by Alfred Price. The Association of Old Crows/Port City Press, 1989, p131-133.

In the late 1940s the Navy's BuAer was responsible for the development of airborne countermeasures systems and the idea of spraying chemicals into the air to produce large radar echoes as a "liquid chaff" attracted significant effort. Iron pentacarbonyl, a straw-colored liquid used in the cores of electrical transformers and in the magnetic coils of certain radio and TV coils, was the subject to much experimentation in 1948. Upon contact with the air, iron pentacarbonyl undergoes a chemical reaction which results in a cloud of iron oxide particles which the Navy surmised might block radar beams. Initial experiments involved spraying the chemical from a boat, but results were inconclusive.

On 10 November 1948 a Curtiss SB2C Helldiver was used to spray 60 gallons of iron pentacarbonyl over Chesapeake Bay while flying at 130 knots and 500 feet altitude. Along the shoreline, the Navy set up various radar systems at six different locations operating at different wavelengths from 200 to 9100 MHz to track the Helldiver as it sprayed the chemical.

There was a brief signal at 700 MHz, but for the most part the radars saw nothing. Visually, however, it was spectacular according to eyewitnesses to the tests. As the clear chemical came in contact with the air, it turned into a black vapor which several feet behind the aircraft then burst into a brilliant flame that varied between dark red and light orange that extended past the Helldiver for approximately 10 plane lengths and persisted for several seconds. As the flame darkened to a red color, the cloud turned black again and then a rust color before dispersing.

The pilot during the tests refused to fly further missions to test the iron pentacarbonyl and the Navy ended its tests with no indication that it blocked radar beams. However, for days after that November tests, reports came from different communities along Chesapeake Bay of some sort of "burning rain" that damaged paint on cars, discolored houses, and allegedly damaged clothing on clotheslines. With the Pentagon and the Navy quiet, the state of Maryland conducted an investigation and concluded that the culprit were rotting skunk cabbages on the bay shore that exuded sulphur dioxide that reacted with water vapor to produce sulphuric acid vapor (acid rain).

Naturally, the Navy didn't feel the need to correct the conclusions of the state investigation and no further tests of liquid radar countermeasures were attempted again.

Source: The History of U.S. Electronic Warfare, Volume II- The Renaissance Years, 1946-1964 by Alfred Price. The Association of Old Crows/Port City Press, 1989, p24-25.