VIETNAM WAR USAF ECM PODS
The initial bombing of North Vietnam began on 3 March
1965. Known as Operation ROLLING THUNDER, it lasted
until 30 October 1968. North Vietnam was defended by to
SA-2 Guideline (Soviet designation V-750 or S-75) Surface-toAir-Missiles (SAM) that relied on the SNR-75 fire control and
tracking radar, known by its NATO code name of FAN SONG.
The SAMs forced the attacking aircraft (primary F-105D/Fs) to
fly at lower altitudes, which made them vulnerable to AntiAircraft Artillery (AAA), much of which was directed by the
SON-9 FIRE CAN radar. Electronic Countermeasures (ECM)
pods were introduced by the USAF to defeat these radars.
Since the primary threat, the SA-2, was only found in North
Vietnam, when looking at contemporary photos from the war,
if an aircraft had ECM pods, it was headed for North Vietnam.
If it didn’t, it was going to South Vietnam, Laos or Cambodia.
It’s helpful to know how the FAN SONG radar worked. This,
believe it or not, is a VERY simplified explanation! (Since
the Vietnam War, NATO has changed the radio frequency
band designations. For this explanation, the original band
designations are used.) The FAN SONG had three antennas:
A rectangular vertical trough that tracked target
elevation operating in the F-band using vertically polarized
beams. The U.S. ECM antennas that addressed azimuth were
referred to as EVEN antennas.
A horizontal trough that tracked target azimuth
operating in the E-band using horizontally polarized beams.
The U.S. ECM antennas that addressed elevation were
referred to as ODD antennas.
A dish antenna at the end of the horizontal trough
sent guidance signals to the missile in C-band, with the missile
responding in F-band.
The SA-2 missile had two stages. Once the first (booster)
stage burned out and fell away, it uncovered the ‘beacon’
antenna at the back of the second stage, allowing the Fan
Song’s dish antenna to guide the missile using a sequence of
three-pulse groups known as ‘triplets’.
The initial variants of the AN/ALQ-71 and AN/ALQ-87 were
each composed of two cannisters which contained two
transmitters each. Initially, the pods were configured with
two jammers assigned to barrage jam the Fan Song with the
other two jamming AAA radars.
The QRC-160-1 was the pre-production variant of what
became the AN/ALQ-71. It was used on three 45th TRS RF101Cs flying out of Tan Soh Nhut AB (near Saigon) on 29
April 1965. Each jet carried four pods! They used two pylons
with either one pod, or two using a dual adapter (the only
Author: Jim Rotramel
published photograph of an RF-101C with a QRC-160-1 shows
a single parent-mounted pod). The RF-101C was not designed
with wing pylons and the jury-rigged installation had adverse
effects on the aircraft and the aerodynamic vibrations
damaged the pods. So, this poorly thought out experiment was
quickly ended. The pods themselves were then made more
physically robust (including the addition of two hardbacks on
the top of the pods) and redesignated QRC-160A-1.
As losses of F-105D/Fs mounted during 1966, the idea of
using ECM pods was revisited. Despite some initial misgivings,
the 355th TFW at Takhli RTAFB began carrying QRC-160A-1
pods on 26 September 1966. The pods proved so successful
that soon every 355th jet was carrying pods under both wings!
However, there was a limited number of pods at the time
(about 140), so half were given to the 388TFW F-105D/Fs
at Korat RTAFB. By November 1966 all F-105D/Fs flying over
North Vietnam were equipped with QRC-160A-1s. The most
famous use of the QRC-160A-1s was during Operation Bolo
in January 1967, when 8th TFW F-4Cs borrowed some pods
and pretended to be F-105s. Carrying the pods on the right
outboard wing pylons, they lured 11 North Vietnamese MiG21s into a trap, shooting down seven.
Production versions of the QRC-160A-1 pods, known as AN/
ALQ-71(V)-2, began arriving in Thailand in December 1966.
During this initial time period, the F-105D/Fs flew in carefully
defined four-ship ‘pod’ formations to maximize jamming
effectiveness. Lead (#1) carried a pod mounting EVEN
antennas. Assistant flight lead (#3) carried a pod mounting
ODD antennas. Their wingmen (#2 & #4) would carry at least
one pod on an outboard station and, by the end of 1967, on
both outboard pylons, one each EVEN and ODD, with the EVEN
pods mounted on the wings on the outside of the formation.
(Beginning in December 1966, Lead and three often carried an
AERO 3B-mounted AIM-B Sidewinder on the opposite outboard
The so-called ‘SPECIAL’ pods were a slight modification of the
original pods that used all four transmitters to block the SA-2
guidance (beacon) commands. Beginning in November 1967,
388th TFW Wild Weasel F-105Fs began using a configuration
of two pods per aircraft: one standard (sometimes called
‘NORMAL’) and one beacon configured (almost always marked
as ’SPECIAL’ on the side of the pod). Strike F-105D/Fs of the
355th and 388th TFWs adopted this practice the following
month. AN/ALQ-71s were used as SPECIAL pods prior to April
1968, but gradually gave way to the more powerful AN/ALQ87s for this task by July 1968.
By 1968 all aircraft using ECM pods were modified to provide
INFO Eduard - December 2019