Night Hunter Operations

by Captain Richard C. Keehn

U.S. Army Aviation Digest – May 1969

[Text version]

From 31 Oct 68 through 4 Nov 68 a new operational concept directed against enemy forces and logistical traffic in the Mekong Delta was put into effect. This new operation, called the "Night Hunter Concept," was tested by A Troop, 3rd Squadron, 17th Cavalry in support of the 1st Brigade, 9th Infantry Division.

For this type operation to be successful, the terrain had to be sparsely populated with only scattered heavy vegetation and the area of the Mekong Delta just south of Saigon proved to be ideal. This area was level, open country, with easily definable waterways lined with nipa palm and large areas of rice paddies with scattered patches of trees, and brush.

Populated areas proved to be no problem in most cases as these areas were usually in concentrations adjacent to the rice fields or in clusters along the navigable waterways where the nipa palm was the thinnest and did not obstruct access to the waterways.

The Night Hunter operation was designed to exploit targets acquired by ground surveillance radar. The Night Hunter Task force consists of a mobile AN/TPS 25 radar set, an air cavalry element, roving waterborne patrols, infantry ambush sites and supporting artillery.

The command and control element was located at the ground surveillance radar detection center and included the infantry brigade commander, the direct support artillery battalion commander, commander or S-3 of the air cavalry element and the command element of the waterborne forces.

The command and control element directed the radar search patterns and analyzed the sightings as they were acquired and plotted. Small isolated sightings were attacked by artillery alone. When a target of sufficient magnitude and concentration was detected, the entire task force was put into action.

The maximum shock action, surprise and fixing of the enemy timetable was carefully followed. When all the elements of the task force had been briefed, an artillery time-on-target (TOT) was initiated which would bring variable timed high explosive rounds, illuminating rounds and the air cavalry elements into action simultaneously. When targets were within population overlays, only illuminating rounds were used. Continuous artillery illumination was adjusted by the air cavalry fire team leader until the entire enemy target area had been searched. When a target was acquired by the air cavalry elements, it was subjected to an immediate and devastating attack by miniguns, 40 mm grenades and 2.75 inch rockets. The waterborne forces were maneuvered into an area adjacent to the target area, water routes permitting, to engage enemy personnel attempting to flee the target area.

The operation scored 67 kills and destroyed 15 sampans with two secondary explosions in four nights of operation. On the first operation, the night of 31 October, the air cavalry element registered 14 kills on four separate engagements, three of which resulted in later contact for the waterborne forces and resulted in three additional KIAs. The second night, the air cavalry scored one kill and destroyed two sampans in two engagements, and the waterborne forces killed 15 enemy attempting to flee the target area. The third night the air cavalry killed 15 enemy and destroyed four sampans, two of which resulted in secondary explosions.

The fourth night, there was no operation due to heavy daytime cavalry commitments. The last night, 4 November, the air cavalry killed 16 enemy and destroyed eight sampans, three of which were loaded with supplies. The waterborne forces killed an additional four of the enemy in a later engagement.

The mobile AN/TPS 25 radar utilized during the operation covered a searching radius of 20 kilometers in a 360 degree radius. The entire area was broken down into four equal quadrants. Each quadrant was searched as directed by the command complex. As targets were sighted, they were recorded and plotted on the master overlay. As radar sightings accumulated, definite patterns emerged, showing numbers of personnel, direction of movement and density of movement in a given area.

Two-way radio communication was established between the radar operator and the air cavalry element in the air. When a target complex was under attack, the radar would scan the area 2 kilometers either side of the target. With minimal training the radar operator was able to vector an aircraft to the center of target movement if it was flying at or below 200 feet above ground level and all other aircraft were at a higher altitude.

The OH-6A was normally used because it returned a special radar echo that made it easy to distinguish from other type aircraft. When the cavalry scout element was directly over the target the radar operator would transmit the word "target" The OH-6A would thoroughly search the area and call in AH-1Gs to destroy the enemy. The use of radar to adjust rocket fire into an isolated, heavily vegetated area was experimented with successfully. The Cobra team leader would expend one pair of rockets on the target area and the radar would adjust the fire. The team.leader's wing man would commence his attack with the necessary corrections and devastate the area.

The enemy position which had been destroyed would be monitored later from time to time to see if any movement recurred in the area. As each target in the complex was neutralized the radar would direct the pilot to a new target in the area. In several instances the radar plotted sampans moving along a river and was able to plot to which side of the river the enemy had fled and the direction of his movement.

Three tango boats were used during the operation, without troops on the first night and with two platoons of infantry the remaining nights. The tango boats were armed with machineguns, grenade launchers and a 106 mm gun. Starlight scopes were used for initial target acquisition. The starlight scopes proved extremely effective in all engagements. Illumination for engagements was available by flares shot from T Boats or an artillery battery located at the command complex.

Strategic numbered check points on navigable rivers were plotted on all maps of the cavalry elements, tango boats and the command and control complex. The entire Night Hunter Task Force kept track of the tango boats movement. When a significant contact was made, troops could be dismounted and air cavalry located at the staging area could be scrambled and airborne over the engagement in less than five minutes. If the air cavalry was airborne neutralizing another target area, it could be diverted immediately to the tango boats engagement, giving sustained close air support to the infantry on the ground pursuing the retreating enemy.

Two artillery batteries were used during the testing, one battery of 155 howitzers and one battery of 105s. Sufficient illumination rounds were on hand for six hours of continuous illumination. Varied heights and amounts of illumination were tried during the first two nights of the operation. Ideal illumination was attained on the third night. With a bright moon two artillery flares over the target area igniting at an altitude of 400 meters and followed immediately by two more flares at an altitude of 600 meters provided good illumination. Continuous illumination, one round every 60 seconds at an altitude of 600 meters, was provided following the initial rounds. During dark moon phase the same initial illumination was used. Continuous illumination was shot every 30 seconds. When more than one target complex was sighted and plotted, data was sent to the artillery batteries for the primary and secondary targets. One battery was utilized on the initial target while the second battery of artillery was primed and ready with high explosive and or variable time and illumination rounds. They were on call from the air cavalry team leader when the primary target had been fixed and neutralized.

When a significant target complex had been sighted and plotted, the data was transmitted by radio to the air cavalry team leader, to include target coordinates, type of targets, number of enemy personnel, route of flight, type of artillery ordnance to be used and projected time-on-target. After the remainder of the flight crews had been briefed, a 10-minute projected time-on-target was initiated, as this proved to be the most effective response time for all elements of the task force. Within five minutes of the projected time for on target, all aircraft were ready for takeoff. Takeoff was on order of the command element based on the calibrated mission data.

On command the aircraft would take off and form a staggered trail formation in the following order: one OH-6A, two AH-1Gs and one UH-1H. The cavalry elements would fly the flight route based on a given airspeed and prominent check points easily distinguishable from the air at night. The cavalry would arrive over the release point 2 miles from the target complex at one minute projected time-on-target. The cavalry team leader was then given 10 second count downs and artillery "shot" and "splash" information from the command element. The team leader had to traverse the final distance to arrive one-half to one-fourth mile from target at zero hour.

During the initial approach to the target area the formation was changed to staggered three abreast, with the OH-6A in the middle. The UH-1H remained one-fourth mile behind the attacking elements. A shallow dive was initiated from 1,500 feet into the target area with each aircraft 200 yards apart. If the enemy was seen fleeing the area, they would receive immediate fire from anyone of the three cavalry elements. If no enemy were seen the two Cobras would level out at 75 feet and continue their pass through the area. The OH-6A would continue its descent to normal scouting altitude and be joined by the UH-1H "firefly." The four aircraft flying low level through the area gave maximum eye coverage to the enemy target. The AH-1Gs would climb alternately to the right or left on command of the team leader, and assume the standard close-air support formation over the firefly and scout aircraft

.

Normal daytime scouting procedures were employed by the OH-6A. The UH-1H flew at approximately 100 feet, roaming back and forth across the area assisting the scout element. Concentrated illumination was afforded by the firefly element.

On the first night of operation two starlight scopes were used on the mission to search the target area without illumination from the UH-1H. This proved unsatisfactory because of the vibration level of the aircraft and the limited area of vision with the scope from a moving aircraft. On subsequent missions only artillery illumination and the firefly were used. Additionally on the first night, flares dropped from helicopters were tried. This proved unsuccessful compared to the artillery illumination. It would have required four additional UH-1Hs loaded with flares to provide enough sustained illumination over the target area. This would have congested the airspace and interfered with the effectiveness of the mission. Throughout the entire four nights of operation standard daylight cavalry tactics were employed after initial illumination.

At the completion of each mission the aircraft would return to the tactically lighted staging area which consisted of two-way radio communications, a refueling area and two re-arming pads. The two re-arming pads each had a stock pile of varied ordnance: 2.75 inch rockets were pre-stacked in two piles of 100 each, consisting of 10 pound and 17 pound VT; 250 rounds of 40 mm grenades and 4,000 rounds of 7.62; two preloaded 7.62 minigun ammo boxes for the OH-6A were also located at the re-arming pads. The replenishment of the two re-arming pads came from the main ammo point located nearby.

A standard mini-pump refueling point was used with a fuel reserve of 5,000 gallons. The mini-pump was preplanned to accommodate 10 aircraft in case airmobile operations were initiated.

The two AH-1G helicopters were armed with 4,000 rounds of 7.62 minigun ammo and 250 rounds of 40 mm grenades in the nose turret. The wing stores consisted of four rocket pods per aircraft. The two outboard pods were loaded with a total of 38 ten-pound VT 2.75 inch rockets on each aircraft. The inboard pods on one aircraft were loaded with 14 seventeen-pound VT 2.75 inch rockets. The other aircraft's inboard pods were loaded with 14 beehive 2.75 inch rockets. The OH-6A was armed with the standard XM-27E1 minigun, with 2,000 rounds of ammunition. The UH-1H had its two standard M-60 machineguns with 4,000 rounds per gun mounted, plus the firefly apparatus.

An additional phase of the operation was to develop an early morning target complex into a significant contact for the deployment of airmobile forces at daybreak. This was attempted at 0430 hours on 3 November. A radar sighting of 50 personnel was made in a heavily populated area along a river. The findings of two large motorized sampans, trails less than 30 minutes old and direction of movement verified the radar sightings. No visual contact was made due to the density of hooches. Airmobile assets were not available until 1000 hours. When insertion was finally made in the area, 10 of the enemy were either killed or captured. Two POWs admitted that 50 NVA troops armed with AK-47s and two machineguns had landed by sampans at approximately 0400 hours that morning and moved to the southeast. The POWs further stated helicopters had been over many of them early in the morning and they were in fact hiding in the hooches. All the facts collected on this one early morning operation gave significant support to the concept's effectiveness.

Two significant facts were established during the Night Hunter Operations:

• Maximum results were obtained with a minimum use of available assets and aircraft flight time. The amount of flight time logged each night by the four aircraft was as follows:

31 October, 02 +- 15 per aircraft

1 November, 01 +- 30 per aircraft

2 November, 03 +- 00 per aircraft

4 November, 01 +- 50 per aircraft

• Enemy movement was reduced significantly each night that the air cavalry was employed. On 30 October, the night before the concept was initiated, there were 138 radar sightings. On 31 October there were 82 radar sightings. On 1 November, only 52 targets were sighted. On 2 November only 38 radar targets were sighted. On 3 November, the cavalry wasn't utilized and the radar sightings jumped to 96. On 4 November a total of 58 targets were sighted.

• Each night the air cavalry was deployed virtually all movement stopped in the radar surveillance area shortly after 2230 hours. Movement resumed in widely separated areas around 0430 to 0500 hours the following morning, thus effectively denying the terrain to the enemy for night movement.

Certain facts were established that helped to successfully accomplish this type of night operation.

• All elements of the task force must be located in the same immediate area with landline and radio communications.

• All key members of the task force, to include all aircrew personnel, must receive a thorough briefing each night to insure all friendly positions are plotted and all operational procedures and contingency plans are completely understood.

• Close co-ordination and timing are absolutely essential to the successful execution of the mission. To obtain split second accuracy the command structure must work side by side using the same clock, maps and overlays.

• One of the greatest potential uses of this type of night operation is to deny the enemy the use of the terrain at night. If the enemy is unable to maneuver, he will be ineffective.

[END]

Submitted by Chuck Oualline

A Troop, 3^rd Squadron 17^th Air Cavalry

Posted 30 August 2005 by the Silver Spurs

Silver Spur Choppers

OH-6A AH-1G UH-1H