A Security Police Sentry Dog Handler’s Perspective

By Phil Carroll
Takhli RTAFB, 355th SPS K-9, Charlie 2M45, 1970
Nakhon Phanom RTAFB, 56th SPS K-9, Tina X768, 1971

It’s been called “the worst base in Thailand, but the best base we had in Vietnam.” It was the home of the 56th Air Commando Wing, renamed in 1968 the 56th Special Operations Wing. It was the closest U.S. Air Force base to communist North Vietnam, and just “eight klicks” from communist infested, war-torn Laos. This proximity was extremely convenient for Air Force combat missions flown from there, and a lifesaver for shot-up U.S. aircrews desperate to put it on the ground right now. This proximity also kept the men and dogs of the 355th Security Police Squadron on edge.

Nakhon Phanom Royal Thai Air Force Base (NKP) was just 75 miles from North Vietnam, somewhat north of Vietnam’s De-Militarized Zone (DMZ) at the 17th parallel, and a straight 230-mile flight from downtown Hanoi. It was within range of known weapons at communist positions in Laos, but sapper attacks were judged to be its greatest threat. As one former officer in the 56th Security Police Squadron said, “Most of the time it seems we were in some form of higher alert due the threat level. Just North of NKP city was a known Communist Terrorist crossing point. In fact, the Sapper Team that attacked Ubon AFB was known to have used that crossing point. Why they bypassed us and traveled all the way down to Ubon is not known. I always told our security troops it was because we were just too damn good, so they were afraid to hit us.”

Although Laos wasn’t “Vietnam,” and the war in Laos officially wasn’t happening, there was war there. Laos had large- and small-unit ground combat, artillery, armor, clandestine operations, mercenaries, saturation and pin-point bombing, close air support, aerial defoliation with Agent Orange, and nightly gunship truck hunts on the Ho Chi Minh Trail. There were 35,000 North Vietnamese Regular Army (NVA) troops in Laos by 1968, and 80,000 by 1970 - experienced enemy combat troops swarming a country the size of Idaho. Some of these NVA regulars were fighting the Royal Laotian Government, and the CIA’s Hmong and Thai mercenary Special Guerrilla Units on the Plain of Jars in northern Laos; most of them were supporting and defending the Ho Chi Minh Trail where it went south - right past NKP. All the troops and supplies to support the communist’s aggression in South Vietnam went down that trail network, so defending it was critical to them. We knew that every bomb and bullet that went down that trail was going to be used against Americans in the south, so stopping it was critical to us.

The Ho Chi Minh Trail in Laos was the focus of U.S. air power after President Johnson terminated Operation Rolling Thunder over North Vietnam in 1968. Operation Steel Tiger bombed eastern Laos, along the Vietnamese border. Operation Arc Light’s B-52 raids included targets in Laos. Operation Barrel Role sent bombers and tactical strike aircraft into northern and southwestern Laos, dropping about 3.4 billion pounds of bombs there between 1968 and 1973.

North Vietnamese communists viewed Laos as more than a transport corridor, though; they saw it as crucial to Vietnam’s own security and as a steppingstone to an eventual takeover of Thailand. The Thai government viewed the whole Nakhonpanom Province of northeastern Thailand as an “Insurgency-Threatened Area,” infested with communists, NVA, and North Vietnamese Viet Minh refugees loyal to Ho Chi Minh. The primary ethnic group present was Vietnamese. The Air Force labeled NKP as being within an “area of significant communist presence,” and a “communist activity area.” In these areas, there were 2,700 attacks on Royal Thai Guard (RTG) units by communist terrorists in 1970, increasing to 3,400 attacks in 1971.

As a busy and effective front-line combat base with an amazing array of aircraft and missions, NKP was a significant irritant and a tempting target for the communists. The 56th earned campaign streamers for Phase II, III, and IV of the Vietnam Air Offensive; the TET 69 Counteroffensive; Vietnam Summer-Fall 1969; Vietnam Winter-Spring 1969-1970; Sanctuary Counteroffensive 1970; Southwest Monsoon 1970; Commando Hunt V, VI, and VII, and Vietnam Cease-Fire 1972-73.

Strikes from NKP were fragged every day in support of MACV-SOG, the so-called “Military Assistance Command, Vietnam - Studies and Observation Group,” a cover name for special operations. This legendary command was only assigned about 2,000 personnel and relied on NKP for helicopters from the 21st Special Operations Squadron, forward air controllers from the 23rd Tactical Air Support Squadron, and fighter/bombers from the 1st, 2nd, and 602nd Special Operations Squadrons.

SOG reconnaissance teams, inserted and backed up by NKP’s Mobile Launch Team 3 “Heavy Hook,” performed road, trail, and river watch missions, prisoner snatches, wire taps, sensor emplacements, and “Bright Light” POW rescue missions.

Shot-down Air Force and CIA fliers were picked up all over North Vietnam and Laos by Combat Search and Rescue (CSAR) units from NKP, sometimes even within sight of NKP itself. One example while I was there was Navy Lieutenant Commander Robert N. Castle, Jr., who was shot down in Laos about 17 miles from NKP on 28 Dec 1970, while flying an A-7E from the carrier USS Ranger. He was rescued by an HH-43F Pedro helicopter, flown by Captain Bobby S. Lay and his crew, of Det 9, 38th Air Rescue and Recovery Squadron from NKP.

Some nights guys on base or in town watched Laotian Air Force AC-47 gunships or NKP’s own AC-119 gunships “hosing” enemy traffic on The Trail.

Ranch Hand herbicide spray missions flew from NKP as early as 1966. These missions defoliated areas surrounding parts of the Ho Chi Minh Trail and had the approval of both the Thai and Laotian governments. C-123 aircraft were used on the missions. The missions were extensive enough to have required pre-positioning or maintaining stocks of the herbicides. This pre-dates the Air Force receiving permission to use herbicides for clearing areas on and around Thailand bases for area and perimeter defense, which was given in 1969. After that, the Air force has written: “NKP also had the usual rainy season vegetation problems, but heavy use of herbicides kept the growth under control in the fenced areas.” They never got permission to spray outside the wire in Thailand.

Another very juicy target for the communists would have been NKP’s Task Force Alpha. These guys, through their top-secret, high-tech “Igloo White” program, littered Vietnam and Laos with thousands of electronic sensors and then monitored signals from them at NKP’s Infiltration Surveillance Center on high-powered IBM computers. Task Force Alpha was the only portion of the base protected by its own high revetments.

On 21 November 1970 elements from NKP joined forces from other bases in Thailand in an offensive rescue mission into the Son Tay prison camp on the outskirts of Hanoi, North Vietnam. While no prisoners were found, the speed and overwhelming force of this well-executed raid helped “encourage” the North Vietnamese to return to the Paris peace talks. In 1972 many of our POWs were returned and reported significantly better conditions after the raid occurred.

On 12 May 1975, the civilian container ship “Mayaguez” was seized by Cambodians and its 40-man crew imprisoned. President Ford wanted an immediate and decisive military response to this piracy, and the Marines were too far away to respond quickly enough to suit him. According to a USAF Security Forces History of Combat Operations, “The men of the 56th Security Police Squadron trained as a unit and were hailed throughout 13th Air Force as a capable assault force. The [President’s] advisors looked for the nearest unit capable of mounting an assault upon the ship under combat conditions. The only unit with such a reputation closer to the scene than the Third Marine Division was the 56th Security Police Squadron at Nakhon Phanom RTAFB.” Seventy-five hand-picked volunteers were quickly assembled, and a rescue attempt was started. Sadly, a CH-53 helicopter, “Knife 13,” carrying a flight crew of five, a linguist, and eighteen Security Police and K-9 troops, crashed into the jungle near the Laotian border in the middle of the night. All on board were killed. Days later, the bloody rescue mission for the Mayaguez crew was finally carried out. Although a number of U.S. Navy, Marine, and Air Force personnel, and 56th Special Operations Wing aircraft were lost, eventually, the crew of the Mayaguez was released.

The point of all this history, at least for this little essay, is there was ample reason for the heavy security at NKP. There was a good reason for the Security Police and K-9 guards there to be just a little on edge. Many, including the Captain quoted above, believe that the reason we weren’t attacked more often was our obvious, in-depth defensive system. We had:

  • A deep, totally herbicide-denuded perimeter with barbed wire fence, triple concertina razor wire, tanglefoot, electronic pressure sensors, mines, more concertina, more barbed wire, and bright, directional perimeter lighting;
  • A series of high guard towers all around the perimeter;
  • Machine-gun bunkers backing up the towers;
  • Numerous security posts manned by the 300-man combat-trained Security Police Squadron with M-16s and M-60s;
  • Nighttime K-9 patrols by 65 sentry dogs and handlers (call sign “Nightfighter”), each with a CAR-15 and 10 magazines of 5.56;
  • Six to eight patrol dogs and handlers, similarly armed;
  • 81 mm mortar teams, with pre-registered coordinates all over the base for flare missions;
  • Roving machine-gun armed truck patrols;
  • M113A1 “Track” Heavy Weapons Teams;
  • XM706E2 “Commando” armored car Quick Reaction Forces pre-positioned and on call;
  • An H-3 “Knife” helicopter patrol, all night every night, ready to probe the jungle outside the wire with an intensely bright searchlight;
  • AC-119 “Stinger” gunship flare missions around the perimeter whenever the intelligence guys asked for it, or in response to an alert by one of the security or K-9 posts;
  • A-1 Skyraider fighter/bombers, AC-119 Stinger gunships, well-armed OV-10 Broncos, and CH-53 Super Jolly Green Giant helicopters that could get guns into the air as quickly as needed.

Of course, no fortress is impregnable, and more than one night we had reason to briefly wonder if the bad guys were finally tired of letting our base exist. I guess we discouraged most attempts by passing the occasional tests of our preparedness when the electronic alarms were set off, one of the K-9s alerted, or somebody heard gunfire on the perimeter. We greeted all these events with fast and aggressive responses, and we were lucky while I was there. I know some weren’t so lucky when NKP was hit later in the war, and I salute those who had to fight to defend NKP, as well as all our Absent Companions.

The 56th Security Police Squadron earned the following honors during the Vietnam War:

  • The Presidential Unit Citation, for extraordinary gallantry in connection with military operations, for each of the following periods:
    • 1 Nov 1968 - 1 May 1969
    • 1 Oct 1969 - 30 Apr 1970
    • 1 Apr 1972 - 22 Feb 1973
  • The Air Force Outstanding Unit Award with Combat “V” Device, for exceptionally meritorious service in support of military operations, for each of the following periods:
    • 1 Jun 1970 - 31 May 1971
    • 1 Dec 1971 - 29 Feb 1972
    • 23 Feb 1973 - 28 Feb 1974
    • 24 Jan 1975 - 2 May 1975
  • The Republic of Vietnam Gallantry Cross, for valor and heroic conduct while fighting the enemy, for the following period:
    • 8 Apr 1967-28 Jan 1973


  1. 121st Security Forces Squadron: Security Forces History, Combat Operations: http://www.121sfs.org/history/combat.aspx
  2. Barnette, Major, and Barrow, Captain, Directorate of Operations Analysis, HQ PACAF: Project CHECO Southeast Asia Report, Base Defense in Thailand (1973) [Note: CHECO is “Contemporary Historical Evaluation of Combat Operations]
  3. Castle, Lieutenant Commander Robert N. Jr.; Interview; http://users.acninc.net/padipaul/pnl016_10_06/SEA.htm
  4. Fox, Roger P., Office of Air Force History: Air Base Defense in the Republic of Vietnam 1961-1973 (1979)
  5. Frommer, Frederick J.: U.S. to Hike Funding to Remove Laos Bombs; Associated Press (2004)
  6. Fuhs, Major Richard R.: post on Vietnam Security Police Association internet bulletin board (2007)
  7. Glasser, Jeffrey D.: The Secret Vietnam War. The United States Air Force in Thailand, 1961-1975 (1995). [Note: this is an incredibly complete and fascinating book about the Air Force’s activities in Thailand during the Vietnam War – I highly recommend the book. It is out of print and hard to find, but worth the effort.]
  8. Hill, Dale, Being On-Scene Commander in a SAR; http://www.fac-assoc.org/23TASSOpening.htm
  9. Jeppeson, Sergeant Chris: The INVERT Page: http://home.att.net/~c.jeppeson/invert_5.html (2003)
  10. Kaylor, Robert: The Secret Is Out: U.S. Base Isn’t Secret Any More; The Washington Post (1968)
  11. Lamey, Colonel Perry L.: Barrel Roll, 1968-73, An Air Campaign In Support of National Policy (1995)
  12. Leary, William M.: CIA Air Operations in Laos, 1955-1974 (2000)
  13. McConnell, Malcolm, Into the Mouth of the Cat, The Story of Lance Sijan, Hero of Vietnam, (1985)
  14. McLucas, Dr. John L.: Reflections of a Technocrat, Managing Defense, Air and Space Programs During the Cold War (2006)
  15. Military Assistance Command, Thailand: Mission Policy on Base Defense (1969)
  16. Priessman, Master Sergeant Kurt (USAF, Retired): Herbicide Use in Thailand – The Relationship to the Rules of Engagement (ROE) and Use in Vietnam and Laos. (2008)
  17. Robins, Christopher; The Ravens, The Men Who Flew in America’s Top Secret War in Laos; (1987)
  18. Ryti, Brad (Webmaster); The MACV-SOG Website: http://www.macvsog.org/
  19. Schemmer, Benjamin F.: The Raid – The Son Tay Prison Rescue Mission (1976, 1986, 2002).
  20. Sweet, John; Nakhon Phanom During the Secret War; http://aircommandoman.tripod.com/index.html
  21. Tilford Jr., Captain Earl H.; Search and Rescue in Southeast Asia 1961-1975; Air University Review; http://www.airpower.maxwell.af.mil/airchronicles/aureview/1980/jan-feb/tilford.html (1980)
  22. Vietnam Security Police Association, Nakhon Phanom RTAFB, http://www.vspa.com/aspprotect/vspa-nav-nkp-01.asp
  23. Vallentiny, Captain E., and Francis, Technical Sergeant D., HQ PACAF, Tactical Evaluation Directorate, CHECO Division: Project CHECO Southeast Asia Report, Attack on Udorn (1986) [Note: CHECO is “Contemporary Historical Evaluation of Combat Operations]
  24. Wetterhahn, Colonel Ralph (USAF, Retired), The Last Battle, The Mayaguez Incident and the End of the Vietnam War, (2001)
  25. Wikipedia: Nakhon Phanom Royal Thai Air Force Base, http://en.wikipedia.org/wiki/Nakhon_Phanom_Royal_Thai_Air_Force_Base
  26. Witterman, Benn: The Origin of the 23rd TASS: http://www.fac-assoc.org/book/P6_002sample_story_april.html (2001)