Name: Blenn Colby Dyer 
Rank/Branch: Lance Corporal/US Marine Corps 
Unit: Headquarters & Supply Company, 
Battalion Landing Team 1/3 
9th Marine Amphibious Brigade 

Date of Birth: 1 June 1944 (Westbrook, ME) 
Home of Record: Standish, ME
Date of Loss: 27 April 1967 
Country of Loss: South Vietnam
Loss Coordinates: 153319N 1094715E (CT700200) 
Status in 1973: Killed in Action/Body Not Recovered 
Category: 5
Aircraft/Vehicle/Ground: UH34D "Seahorse" 
Other Personnel In Incident: James A Benton, Reinaldo A. Castro, Richard H. Dallas, Samuel W. Osborne, Jr. and Ronald K. Pennington (missing) 


SYNOPSIS:  One of the earliest helicopters employed in Southeast Asia, and the primary Marine Corps helicopter used during the early years, was the Sikorsky UH34D Seahorse. These machines were already quite old when they arrived in the battle zone. However, both the US and South Vietnamese military found them to be extremely effective throughout the war.

Marine amphibious troops stationed aboard ships would use the Sikorsky H34s to insert troops into mission areas. By doing so, the Marines could travel light while completing sea-based assaults, then returning to their ships after each operation to prepare for the next one.

On 27 April 1967, LCpl. Richard H. Dallas was a crewman assigned to a UH34D helicopter transporting members of the 9th Marine Amphibious Battalion (MAB) out to a US Navy ship. On board the Seahorse were passengers LCpl. James A. Benton, Sgt. Reinaldo A. Castro, PFC Samuel W. Osborne, Jr. and LCpl. Ronald K. Pennington, who were all assigned to Headquarters and Supply Company, Battalion Landing Team (BLT) 1/3, 9th MAB. Also on board was LCpl. Blenn C. Dyer from BLT 1/5, 9th MAB.

Just before the aircraft crashed into the South China Sea, the pilot made an emergency Mayday call and gave their position. Search and recovery (SAR) operations were launched immediately for the downed crew and passengers and rescue helicopters were on site within minutes of the loss. SAR personnel were able to rescue the pilot and co-pilot of the Seahorse along with some of the passengers from the two companies being transferred. However, they were unable to find any trace of James Benton, Reinaldo Castro, Richard Dallas, Blenn Dyer, Samuel Osborne and Ronald Pennington. At the time the formal search effort was terminated, all six men were listed Killed in Action/Body Not Recovered.

The Seahorse was approximately 70 miles east-northeast of Chu Lai and 106 miles east-southeast of DaNang, in the adjacent
water where Quang Nam and Quang Tri Provinces join, South Vietnam, when the pilot made his last radio transmission.

The Marine Corps believes the five passengers and one crewman drowned in this Maritime accident when they were unable to escape the downed helicopter before it sunk to the bottom of the South China Sea. Likewise, it is unknown if the Seahorse crashed because of battle damage or a mechanical failure.

Under the circumstances, it is highly unlikely the remains of the men killed in this tragic loss at sea can ever be found. However, for other Americans who remain unaccounted for in Southeast Asia, their fate could be quite different.

Since the end of the Vietnam War well over 21,000 reports of American prisoners, missing and otherwise unaccounted for have been received by our government. Many of these reports document LIVE American Prisoners of War remaining captive throughout Southeast Asia TODAY.

American servicemen in Vietnam were called upon to operate in many dangerous circumstances both on and off duty, and they were prepared to be wounded, killed or captured. It probably never occurred to them that they could be abandoned by the country they so proudly served.