1972-Contin ued

11 February The Navy announced that the develop-

ment and installation of mufflers on engine test cells at

the Naval Air Rework Facility, Alameda, Calif., had

eliminated 85 percent of the audible noise in testing

jet engines for the A-3.

29 February During the month, naval air attack sor-

ties in SVN had risen to 733 compared to 8 during

January. The increase was due to the preemptive

operations by allied forces in preparation for an

expected large-scale enemy offensive during Tet

which did not materialize. Constellation, Coral Sea and

Hancock served overlapping tours on Yankee Station,

assuring two to three carriers on station at a time dur-

ing most of the month.

10 March There were limited attack strikes into

NVN; however, protective reaction strikes increased

significantly. During the period 5 January through 10

March there were 90 protective reaction strikes by

USN and USAF aircraft against surface-to-air missile

and antiaircraft artillery installations, compared to 108

such raids during the entire year of 1971.

16 March HAL-3, the only armed UH-1 Navy heli-

copter squadron to serve in Vietnam, was disestab-

lished. HAL-3 and VAL-4 were the only Navy air units

to be homeported in-country. HAL-3 provided valu-

able gunship support for Navy and Army riverine

operations in the Mekong Delta from 1967 to their dis-

establishment. During this time HAL-3 pioneered vari-

ous tactics in support of patrol boats and shore instal-

lations. They operated from various bases in the

Mekong Delta and from specially-equipped Patrol

Craft Tenders (AGP) (former LSTs).

23 March VMA-513 completed the Harrier DOD sor-

tie rate validation and demonstrated the capability of

the AV-8A to respond rapidly and repeatedly to

requests for close air support while operating from

austere forward bases. During the ten-day test, the

squadron flew 376 sorties with a complement of six

aircraft.

24 March A QF-4B target aircraft that the Naval Air

Development Center, Warminster, Pa., had converted

from a combat configuration into a maneuvering tar-

get, was delivered to the Naval Missile Center for test-

ing. The QF-4B would fulfill the requirement for a full-

size, high-altitude, supersonic, maneuvering aerial

target capable of flying at altitudes in excess of 50,000

feet and at airspeeds exceeding twice the speed of

sound.

UNITED STATES NAVAL AVIATION 1910-1995

291

29 March The BQM-34E, supersonic Firebee II, was

utilized by the Atlantic Fleet Weapons Range for the

first time in missile defense exercises with Wainwright

(DLG 28). The target was launched from a DP-2E at an

altitude of 20,000 feet and accelerated to Mach 1.52

while testing the ship's ability to withstand penetration

of high altitude, high speed enemy craft.

29 March Due to the fleet requirements for qualified

aircrew personnel, the Naval Air Technical Training

Unit's Photographer's Mate Class "A" School initiated

flight training again as part of the course. The flight

training requirements for the Photographer's Mate

Class "A" School had been dropped 16 years earlier.

30 March Naval Air attack sorties in SVN had

dropped from 733 in February to 113 during March.

On 23 March the U.S. canceled further peace negotia-

tions in Paris, France, because of a lack of progress in

the talks. This was followed by the North Vietnamese

invasion of SVN. This "Easter or Spring Offensive" was

the result of the long buildup and infiltration of NVN

forces during previous months and presaged some of

the most intense fighting of the entire war. The NVN

invasion prompted increased air operations by the car-

riers in support of South Vietnamese and U.S. forces.

The carriers on Yankee Station when NVN invaded on

30 March were Hancock and Coral Sea. During the

month four carriers had rotated on Yankee Station;

they were Constellation, Kitty Hawk, Coral Sea and

Hancock.

1 April VAL-4, the last Navy combat force in

Vietnam, was withdrawn. VAL-4 flew the OV-10

Bronco and its mission had been to provide quick

reaction and close support for river patrol boats and

the mobile riverine forces in South Vietnam.

5 April Operation Freedom Train involved Navy tac-

tical air sorties against military and logistic targets in

the southern part of NVN that were involved in the

invasion of SVN. The operating area in NVN was limit-

ed initially to between 17° and 19°N. However, special

strikes were authorized against targets above the 19th

parallel on various occasions. The magnitude of the

North Vietnamese offensive indicated that an extended

logistics network and increased resupply routes would

be required to sustain ground operations by NVN in

their invasion of SVN. Most target and geographical

restrictions that were placed in effect since October

1968 concerning the bombing in NVN were lifted

gradually and the list of authorized targets expanded.

Strikes in NVN were against vehicles, lines of commu-

nication (roads, waterways, bridges, railroad bridges

and railroad tracks), supply targets, air defense targets