Air Support
Cambodian Invasion
Project CHECO
On 27 March 1970, an ad hoc planning group meeting was held at MACV headquarters. During this meeting, 7AF representatives emphasized the need for complete photo reconnaissance and urged that ARVN airborne units and interdiction airstrikes be used to seal the back- side of the FISHHOOK. Neither idea was incorporated into the campaign plan which the ad hoc group proposed and the Commander, U.S. Military Assistance Command (COMUSMACV) forwarded to the JCS on 29 March.
The 7AF did not receive instructions to begin definitive planning until 27 April 1970, too days before ARVN's entry into the Parrot's Beak. Even then, the strict "eyes only" top secret security measures restricted briefings to "key officers." Every effort was made to prevent any leaks to the press and to time U.S. entry into the FISHHOOK to coincide with the President's message on Cambodia. The basic concept for air support was to provide all sorties required on a first priority basis. A JCS message of 25 April had revised the priorities for tactical air to be: (1) Cambodia; (2) South Vietnam; (3) BARREL ROLL; and (4) STEEL TIGER.
As it had done in the past, the flexibility and responsiveness of tactical air was demonstrated. The Tactical Air Control System met the requirements of the Cambodian operations with routine efficiency. Only a few special arrangements were needed. On the evening of 28 April, TACC alerted the Direct Air Support Centers (DASC) and fighter wings to be ready to support ARVN operations in the Parrot's Beak if ordered to do so. The FAC and fighter pilots were to follow normal in-country Rules of Engagement and operating procedures and were cautioned to exercise extreme vigilance to avoid dropping ordnance on the noncombatant populace. Air Liaison Officers (ALO) were to encourage the ARVN units to which they were assigned to use Vietnam Air Force (VNAF) assets. The Parrot's Beak operation was to be a Vietnamese show with U.S. involvement kept to a minimum. Backup search and rescue (SAR) forces were augmented by moving four A-1 aircraft from Nakhon Phanom and two HH-3E helicopters from Da Nang to Bien Hoa and placing one AC-130 gunship on ground alert at Tuy Hoa.
The FISHHOOK operation required a few additional preparations, as it was primarily a U.S. action. Besides the SAR aircraft already on station, TACC allocated two Blindbat flareships at Cam Ranh Bay, four AC-119K gunships at Phan Rang, and ten additional alert sorties at Bien Hoa and Phan Rang. They also organized Spat and Sleepytime FACs for night strikes and set up a refueling track southwest of Ban Me Thout. A message of 30 April to the Direct Air Support Centers (DASCS) and fighter wings informed them that U.S./ARVN forces would begin operating in certain areas of Cambodia adjacent to III Corps and repeated the instructions to use normal operating procedures and to exercise extreme vigilance to avoid dropping ordnance on the noncombatant populace. For security purposes they were to submit only one copy of their After Action Reports, OpRep-4. by 7AF courier. Fighters on Cambodian missions were sent to in-country rendezvous near the FISHHOOK. The pilots were not briefed until just prior to the initial missions that they were going into Cambodia.
FACs used the built-in mobility of the Tactical Air Control System to support the ground units to which they were normally assigned by operating from their radio jeeps and flying, when necessary, out of the forward operating bases. The FISHHOOK action (TOAN THANG 42) came under control of Task Force Shoemaker which was set up by the Commanding General of the lst Air Cavalry Division. The ALO of the 1st Air Cav Div appointed his deputy as the Task Force ALO.
To facilitate coordination of airstrikes and artillery fire within the narrow confines of the areas of operation (AO) designated for the first day's operation, the Task Force ALO set up a special Tactical Air Control Party (TACP) in the Tactical Operations Center (TOC) at Quan Loi, Task Force Headquarters. Under call sign Rash Advon, this TACP took over control of the operation from Rash Control, the normal TACP located at Phouc Vinh. The ALO of the 3d ARVN Airborne Battalion (Abn Bn) also moved his Red Marker TACP and aircraft to Quan Loi. The Rash 30 TACP supporting the 3d Brigade (Bde), and the Nile TACP supporting the 1lth U.S. Armored Cavalry Regiment (ACR) were already located at Quan Loi. Nile FACs flew their 0-2 aircraft out of Bien Hoa as usual, because the runway at Quan Loi was too rough for the 0-2.
To enhance control and reduce air traffic complications, an 0-2 aircraft was set up out of Di An to act as an airborne controller with the call sign Head Beagle. FAC Instructor Pilot controllers flew in the right seat. This arrangement greatly facilitated handling of the numerous airstrikes delivered during the first four days of the operation. Head Beagle circled at about 8,000 feet altitude inside the RVN Border south of the FISHHOOK. Rash Advon passed the fighters to Head Beagle, who in turn directed them to the proper FAC from the standard rendezvous established for each AO. By contacting the FAC about 15 minutes before the scheduled time over target (TOT) of each mission, Head Beagle was able to monitor the weather and the FAC's ability to handle the strike as scheduled. If a FAC were running behind, or if one needed an immediate airstrike or a particular type of ordnance, Head Beagle would hold the fighters at the rendezvous or divert them as needed. This tactic had been combat tested at the siege of Khe Sanh and other localized operations.
The lack of current intelligence during the first few days of all the operations made targeting difficult. Although there were numerous sources, the vast majority of those made available were outdated, most of them by weeks and even five and six months. While the evidence was sufficient to indicate general locations of the base areas, it did not adequately identify the exact locations of the enemy's defensive positions. This problem was complicated by delays at MACV in the dissemination of Air Force photo reconnaissance to the field commanders. This problem continued throughout the first week of the operation, with pictures arriving 24 hours after ground units moved into a new area.
Because intelligence estimated that the FISHHOOK was occupied by an enemy force of about 7,000, the concept was to suppress enemy resistance by use of massive airstrikes for landing zone (LZ) and objective preparations. The 1st Air Cav Div G-2 had compiled a list of 381 targets from an all-source intelligence readout provided by the Combined Intelligence Center, Vietnam. An air operations FAC and an artillery officer platted all 381 targets and labeled them by type on a map. They then identified areas of concentration and established the following priorities for strikes: (1) antiaircraft and automatic weapons Positions; (2) strongpoints; (3) headquarters; (4) base camps; (5) bunker complexes; and (6) storage areas. The main objective was to hit points of suspected resistance in the objective areas of each unit.
The next requirement after softening up the objectives was to have continuous air cover available for close air support of troops in contact and targets of opportunity. The FAC proposed a schedule which divided 37 airstrikes of two sorties each from 0700-1900H at fifteen-minute to one-half hour intervals between the three AOs. To be absolutely certain sufficient air coverage was available to cover any contingency, the number of airstrikes was changed from two to four sorties per airstrike for the first day's operation. In addition to these 148 tactical air sorties, six B-52 ARC LIGHT strikes of six sorties each were requested for six target boxes along the southern border of the FISHHOOK from 0415-0540H on 1 May 1970. These airstrikes were also targeted from the dated intelligence in the CICV target list. There was no current intelligence from infrared (IR), sniffer, side-looking airborne radar (SLAR), sensors, or long range reconnaissance patrols (LRRP). Both tactical air and B-52 requests were processed through normal channels and were approved as submitted.
ARC LIGHT strikes early on the morning of 1 May 1970 signaled the entry into Cambodia by U.S. ground forces. The first tactical airstrikes hit their targets about 0700H and units of the Task Force moved by ground and air across the border on schedule. The 1lth ACR moved overland from the south, the 3d Bde closed from the west, and the 3d ARVN Abn air assaulted from the northeast. Army hunter-killer teams composed of light observation helicopters (LOH) and Cobra gunships ranged over the northwest front to cut off the enemy's escape.
Head Beagle passed the fighters off to the FACs in their respective AOs and proved to be the integral link in the successful handling of 144 preplanned and 48 immediate airstrikes delivered throughout the day. This was no mean task as the fluid nature of the ground battle continually demanded changes in the schedule. Although ground contact was limited to small engagements, demands for support of troops in contact and strikes against targets of opportunity necessitated diverting most of the airstrikes from the preplanned coordinates. The uncertainty of friendly locations and the absolute necessity to avoid noncombatant casualties delayed clearances and required some fighters to hold 15 to 30 minutes.
At his evening staff meeting on 1 May, the Commanding General of II Field Force Vietnam (FFV) stated the day's operation far exceeded his expectations, everything had gone like clockwork with the airborne assault achieving complete surprise. Not one friendly soldier was killed and only 12 were wounded, as compared to about 390 of the enemy killed in action (KIA). Allied airpower contributed greatly to these results.
The planning of preplanned targets continued to suffer from the lack of real time intelligence. Consequently, the second and third day targets were merely selected from the dated list of 381 targets passed down from division headquarters for the first day's planning. However, this was not of critical importance as the ground commanders' primary interest was to have airstrikes available throughout the day to support troops in contact (TIC) situations and to hit targets of opportunety. The divert rate from the preplanned coordinates bore this out. While the concept of operation did not change, the quality of intelligence did improve after the fourth day. Information from IR, SLAR, army photo reconnaissance, visual reconnaissance (VR), and prisoner of war (PW) reports started to accumulate. The Division G-2 used this intelligence to compile a new list of 160 targets on the fourth day and another list of 264 targets on the sixth day.
Although the number of preplanned airstrikes remained about the same for the second day, the number of sorties was cut in half by reducing the request from four to two sorties per airstrike. When the number of sorties requested increased to 89 the third day and Jumped to 128 the fourth day, the TACC recommended that as enemy resistance was light, air could be more effectively managed by cutting down the number of preplanned requests and relying on immediate airstrikes from ground alert to fill in the gaps. This suggestion was accepted and preplanned sorties dropped successively to a low of 20 on the eighth day and fluctuated about a lower level throughout the rest of the campaign.
The concept of the operation changed drastically late in the evening of the second day, 2 May 1970. At midnight, the Task Force Commander, told his commanders that SLAR and other reports indicated the enemy was escaping the area by Highway 7 to the north. He outlined a plan for the 2d Bde to air assault into position just south of Snuol to block Highway 7 and for the llth ACR and the 3d Bde to attack to the north. This required an all night preparation and was accomplished without the benefit of photo reconnaissance of the area. The TACC suggested to the Task Force Commander that the Air Force select an interdiction point (IDP) to the north of Snuol and seal off the road. Uncertainty as to whether the Rules of Engagement would allow airstrikes in that area postponed further consideration of this idea until the fourth day.
The new plan more than tripled the size of the Task Force's AO, greatly relieving the air congestion but also vastly increasing the task of locating the enemy. The 2d Bde air assaulted south of Snuol on schedule during the morning of 3 May and the 1lth ACR started a move north which brought their units up Highway 7 to the outskirts of Snuol by the afternoon of 5 May. The fast-changing ground situation negated efforts to preplan air targets and most of the airstrikes went against targets of opportunity and in support of TICs developing out of the tactical situation.
The close cooperation between the FACs and LOH scouts made them an effective combination. The 3d Bde had developed a system whereby a FAC would fly cover for a White Team (two LOH scouts). The FAC gave directions to the scouts while one scout went down low looking for targets and the other flew larger circles above him. When they found a worthwhile target or received ground fire, the FAC would get the fighters on station. The scout then marked the target with a smoke grenade and the FAC used this mark as a reference to put in his marking smoke rocket for the fighters. If time permitted, the scout checked the target and remarked between fighter passes. After the strike, the scouts descended below treetop level to make an accurate assessment of the damage.
An example of the results of such cooperation occurred on 3 May. Rash 32 was working with a White Team led by Accent 81. They were flying up Highway 7 when Accent 81 spotted tire tracks which led to some poncho covered shelters and a 2 1/2-ton truck camouflaged under the trees. Rash 32 diverted in two strikes but both of them missed the truck. Rash 32 had to respond to a TIC, and Accent 81 returned to Quan Loi for fuel. After lunch they returned to the area and Rash 32 put a strike of high drag bombs on the target. Again the truck was missed, but the blast cleared away the foliage so the scouts could clearly see stacks of crates full of weapons. About 1600H, Accent 81 landed and found a cache containing about 100 cases of new SKS and AK-47 rifles (20 each), a large wheel-mounted recoilless rifle, three 50-cal weapons, a pile of about 500 old AK-47 rifles, and uncounted other weapons under tarps. Rash 32 requested two immediate airstrikes. The first strike of CBU munitions resulted in four secondary explosions. Later ground exploitation of the area uncovered one of the largest weapons caches discovered during the operation.
Requests for BULLPUP and PAVE WAY bombs for strikes on point targets, such as bridges, could not be honored by the TACC, because the delivery aircraft were based in Thailand, and the Rules of Engagement would not allow use of Thai-based aircraft in Cambodia.
By the end of the fifth day, the boundaries of the operation in the FISHHOOK had been fairly well established and the ground troops settled down to searching out the area. Operations returned to the normal status of everyday procedures. The Task Force headquarters at Quan Loi was disbanded, and the Commanding General of the 1st Air Cav Div resumed direct control of the operation. Rash Advon ceased operation, returning overall control to Rash Control at Phuoc Vinh. The 3d Bde and 11th ACR FACs continued to operate out of Quan Loi , their normal location, and the 3d ARVN Abn Bde Red Marker FACs moved to Tay Ninh, their normal forward operating location. Head Beagle flew its last missions on the sixth day and the FACs returned to their regular duties.
Considering the small airspace, the fluid ground situation, and the vast numbers of aircraft involved in the first few day's activities, command and control worked smoothly and effectively. One serious accident occurred, however, and several Short Rounds were avoided only by the quick reaction of the FACS. On 2 May, an 0-2 carrying two pilots collided in mid-air with a Cobra gunship. The pilots of the gunship were killed in the crash. Evidently the blade of the gunship cut the 0-2 in half for the FACs both exited the aircraft and descended in their chutes. However, both pilots' legs were amputated below the knees. One was dead when he was picked up and the other died on the way to Tay Ninh in the rescue ship.
On 2 May, Rash 32 prevented friendly casulties by flying his OV-10 directly in front of a Cobra gunship team which had expended rockets on a friendly position and was coming around for a second pass. On the same day, another FAC saw troops moving through the forest when he rolled in to mark a target. Upon checking further, the ground adviser discovered that a friendly unit had moved into the area without his knowledge. The next day a FAC cleared to strike a village also discovered that friendly troops had moved into the area unperceived by the ground commander requesting the airstrike.
The ground commanders gave high praise to the alert, professional manner in which FACs managed the air support rendered during thesefirst hectic days. They spoke enthusiastically about the responsiveness of the air support and expressed the firm conviction that it had thrown the enemy off balance, forced him to scatter, and had been the major factor in keeping the number of friendly casualties low.
Except for slight modifications, the application of airpower in the FISHHOOK was typical of all operations in Cambodia. In an attempt to surprise a suspected COSVN headquarters, the 25th Inf Div deviated from the use of airstrikes for LZ preparations by targeting preplanned airstrikes adjacent to the suspected location to divert attention from the objective area. The only preparation used was heavy artillery immediately prior to the assault.
Except for this attempt to surprise the enemy, the usual procedure was to use extensive airstrikes for LZ and objective preparations to suppress enemy resistance prior to combat assaults. Preplanned airstrikes served primarily as air cover for TIC and strikes against targets of opportunity, and most of them were diverted from the preplanned targets for these uses. After the first few days, the number of air- strike sorties tapered off and fluctuated at a lower level for the remainder of the campaign. After the initial assaults and expansion of the AO boundaries, the ground forces settled down to searching out the areas and evacuating the caches discovered. During this phase, preplanned airstrikes served primarily as air cover and secondarily as a means of reconnaissance by bombing to aid in the discovery and destruction of storage areas. FAC visual reconnaissance missions and FAC coordination with LOH scouts proved particularly effective during this phase.
The foregoing descriptions also apply to the ARVN operations. They were supported primarily by VNAF FACs and VNAF fighter aircraft, and ground commanders adhered closely to methods in which they were trained. The main difference was due to weaknesses in the visual reconnaissance program of VNAF FACS. They generally put in preplanned strikes and then returned to their base. Consequently, VNAF FACs were not as responsive to immediate requests for airstrikes for TIC and targets of opportunity as their USAF counterparts.
During the ARVN operations, the USAF ALOs worked closely with the ground commanders and VNAF ALOS. While the VNAF Facs were engaged in directing the preplanned airstrikes, the USAF FACs picked up the visual reconnaissance role and responded to requests for immediate airstrikes. The level of enemy resistance in the Parrot's Beak was considerably higher than in the FISHHOOK and airstrikes in response to significant enemy contacts were more frequent. Enemy units of battalion size and larger put up intense ground fire against aircraft. On 29 May, while elements of Task Force 225 were in contact in the Parrot's Beak with an enemy force estimated at two battalions, one F-100, one helicopter, and one A-1 were shot down in the same battle. As one USAF FAC conducted the resulting SAR efforts, another directed immediate airstrikes in support of the engagement. After the battle was over, the ground commander estimated more than 100 KBA and at least that many wounded.
The USAF FACs attached to the ARVN units also served in numerous other roles. They were the first to note civilian and refugee locations and passed this information to advisers in the field and political advisers in the province to prevent inadvertent bombing of civilian noncombatants. USAF FACs scouted the areas ahead of ground movements and advised commanders of terrain conditions and the possible location of enemy defenses. On one occasion, a USAF FAC led an ARVN medevac helicopter through intense ground fire in one-half mile visibility to locate a friendly position. He adjusted artillery an the enemy positions while the medevac evacuated the wounded.
Ground commanders' appreciation for the air support they received was reflected in a letter to Gen. George S. Brown, Deputy Commander for Air Operations, MACV, from Lt. Gen. Michael S. Davison, Commander, II Field Force Vietnam:
"Fran Roberts has just provided me with a succinct recapitulation of the close air support we have received in the border areas of III CTZ during the period 1 May - 10 June 1970. I find the total effort expended on our behalf to be extremely impressive, and am enclosing the report as rendered to me, on the chance that perhaps this information hasn't reached you in quite this form. "I'm most appreciative, not only of the amount of support your units have provided to the II FFV and III Corps maneuver elements, but also of the extremely adept and timely manner in which it's been delivered. It has been a professional performance of the highest quality."