I had dinner this week with a veteran of one of the lesser known squadrons that served in the Vietnam War, VO-67. In Naval Aviation parlance, that’s Observation Squadron 67. VO-67 had the dangerous mission of seeding the Ho Chi Mihn Trail with sensors under the aegis of Project Igloo White.

During the Vietnam War, support for the VC and regular units of the North Vietnamese Army traveled via a complex tangle of jungle trails and roads south from North Vietnam through Cambodia and Laos and entered South Vietnam. It was not politically feasible to invade North Vietnam to interdict these supplies, and until 1970, neither was invading Laos with ground troops. That left airpower to interdict the trail. The challenge was to find convoys of troops, trucks, and other transportation assets. The “trail” was actually an ever changing series of trails. Pinpointing the location of NVA forces on the trail was almost impossible. Almost.

In an effort to leverage our technological superiority over the North Vietnamese, Secretary of Defense McNamara the DoD to devise a program where acoustic and seismic sensors would locate NVA forces along the trail and cue observation and strike aircraft to interdict the flow of supplies.

In response, the Navy modified a dozen SP-2E Neptune patrol planes to deploy the sensors. The Neptunes had most of their anti-submarine equipment stripped, additional fuel tanks were installed, weapons were added, and armor plating was added to some critical areas. These modified Neptunes were redesignated OP-2E and deployed to Thailand to seed sensors along the trail in 1967.

Now, the P-2 was a good airplane, but it wasn’t really a speedy airplane. Flying at treetop level over the anti-aircraft defenses of the trail was not without great risk.  VO-67 was only in commission for about a year, and yet they lost 3 aircraft out of the 12 converted. Two of the aircraft were lost with all hands. The third was struck by anti-aircaft fire but the pilot, CDR Paul Milius was able to maintain control long enough for the other crewmembers to bail out. The Burke class destroyer DDG-69 was named for him. He was awarded the Navy Cross for his heroism.

In addition to operations over the Ho Chi Mihn trail, VO-67 seeded sensors around Khe Sahn during the Marines epic siege there.  The information gathered on troop concentrations was used to direct Arc Light B-52 strikes on suspected concentrations.

VO-67 operated in obscurity. Few people knew who they were or what they were doing. The squadron was established overseas, and a year later, was decommissioned overseas as well. The Navy had originally anticipated losses of 50% or greater.  Eventually, the Air Force was able to modify a squadron’s worth of F-4 Phantoms to deploy the sensors, and the faster jet proved far more survivable in the dense anti-aircraft environment of the trail.

In another post, we’ll take a look at another version of the P-2, the AP-2H, and another operator of this big bird, the US Army.