Located approximately 40 miles north of San Diego in North County California is the United States Marine Corps’ largest West Coast expeditionary training facility – Marine Corps Base Camp Pendleton. Covering more than 125,000 acres with both mountainous and coastal training environments, the base is home to 1st Marine Expeditionary Force, 1st Marine Division and 1st Marine Logistic Group. For this article, AeroResource takes a closer look at one of the tenant units of the 1st Marine Expeditionary Force: Marine Aircraft Group 39, and speaks with maintainers and aircrew from some of the subordinate commands.

Coming under the command of the 3rd Marine Aircraft Wing, Marine Aircraft Group 39 (MAG-39) was activated on 16th April 1968 and in 2015 is currently commanded by Colonel Michael J Borgschulte. The mission of Marine Aircraft Group 39 is to provide utility helicopter support, close-in fire support, fire support coordination, aerial reconnaissance, observation and forward air control in aerial and ground escort operations, during ship-to-shore movement and subsequent operations ashore.

MAG-39 is comprised of a number of Squadrons flying some of the latest rotary assets that the USMC has to offer –

  • HMLA-169 “Vipers” operating the AH-1Z Viper and UH-1Y Venom
  • HMLA-267 “Stingers” operating the AH-1Z Viper and UH-1Y Venom
  • HMLA-369 “Gunfighters” operating the AH-1W Super Cobra, AH-1Z Viper and UH-1Y Venom
  • HMLA-469 ”Vengeance” operating the AH-1W Super Cobra and UH-1Y Venom
  • VMM-364 “Purple Foxes” operating the MV-22B Osprey
  • HMMT-164 “Knightriders” operating the CH-46E Sea Knight
  • HMLAT-303 “Atlas” operating the AH-1W Super Cobra, AH-1Z Viper and UH-1Y Venom
  • MALS-39 “Hellhounds” an aviation logistics support unit
  • MWSS-372 “Diamondbacks” an aviation ground support unit


Arriving at Pendleton, it soon becomes apparent just how big the base is. After going through the standard security checks, it is a 15 minute drive to the airfield. At the airfield, AeroResource had the opportunity to speak with some of the aircrew and maintainers based at MCAS Camp Pendleton, from HMLA-469, HMLAT-303 and HMLAT-164.

During a Q&A session, Captain Fisher of HMLAT-303 explained the usual route to become a qualified Marine Corps pilot.

“Anyone that wishes to become a Naval Aviator for the Marine Corps or the Navy must follow a officer training path, attend officer candidate school to earn their commission, next it is off to MCAS Quantico Virginia for 6 months to attend The Basic School (TBS) here you are taught leadership skills,infrantry tactics, tactical awareness as well as basic functions of the Marine Corps.Once you graduate TBS, you are assigned a Marine Occupational Speciality (MOS) for wannabe pilots, it’s off to Aviation Pre-Flight Indoctrination (API) at NAS Pensacola Florida for 6 weeks, the first 4 weeks is all about academics, with a series of tests all of which need to be passed.Depending on your Naval Standard Score (NSS) at the end of the 4 weeks, with a high enough pass score, you then move on to survival training where you are taught survival techniques including underwater survival.”
From API, you move to primary training at either NAS Whiting Field in Florida or NAS Corpus Christi in Texas for 6 months of training on fixed wing aircraft. Training on fixed wing aircraft has recently transferred from the T-34C Turbo Mentor to the T-6B Texan II although a small number of T-6As are operated by the US Navy and Marine Corps at at NAS Pensacola. Once primary training is complete and depending on the NSS attained, for the next six to eight months, all Navy, Marine Corps or Coast Guard helicopter pilot training takes place on the TH-57 at NAS Whiting Field. The B version is the more basic helicopter for initial helicopter training, this lasts for two months before moving to the C version that is instrument rated for the remainder of the training.”
Once training is complete, you will then be assigned a helicopter squadron depending on your NSS and choice of helicopter. The locations for training squadrons are MCAS New River or Cherry Point on the east coast, MCAS Camp Pendleton on the west coast or Kaneohe Bay in Hawaii.”

Following on from the briefing, we were taken down to the ramp and given a walk around tour of a Super Cobra and Venom belonging to HMLAT-303. The Airframer and Flightliner from Maintenance explained the different components they were responsible for and showed us around the outside and inside of each helicopter.

It was obvious due to the space on the ramp that many of the squadrons had deployed elsewhere including some to MCAS Yuma in Arizona and Marine Corps Base Twentynine Palms in California in support of exercise “Scorpion Fire” that was taking place on the ranges around MCAS Yuma. The aim of “Scorpion Fire” was to provide a realistic environment for ground units in need of close air support (CAS). The CAS environment is how the Marines operate during a time of war, and making sure the air and ground units work together effectively is why large-scale exercises like Scorpion Fire are held.

Walking along the ramp brings you to the far end where HMMT-164 “Knightriders” are situated. HMMT-164 are bringing training to an end on the venerable Boeing-Vertol CH-46E Sea Knight, and the squadron will soon receive its first Bell-Boeing MV-22B Ospreys, at which time it will relocate to nearby MCAS Miramar.

HMMT-164 “Knight Riders” entered the history books early in January 1965 as the first squadron to receive the CH-46A – nicknamed “Phrog” by its aircrews. HMMT-164 was also the first squadron to fly the CH-46 into operational combat during the Vietnam War, flying as HMM-164. From 1966 to 1969 the “Knight Riders” were deployed over the skies of Vietnam transporting troops and supplies from ships to shore. Once the “Knight Riders” left Vietnam they relocated to Japan where they were stationed until 1980. Returning back to the West Coast USA, HMM-164 was assigned to MCAS Tustin and later that year was the first to receive the CH-46E variant. The “E” model has remained in service with the Marine Corps from that day to this. On the 1st July 2014, HMMT-164 celebrated their 50th anniversary along with the CH-46 and it is fitting that the first squadron to the fly the “Phrog” will also be the last.

It was obvious that the squadron was looking forward to receiving the Osprey, but there was also a touch of sadness at losing such an iconic helicopter that has been part of HMMT-164 since the start. Earlier that morning, prior to our visit, CH-46s 153302/YT06 and 154478/YT04 departed to the Boneyard (Davis-Monthan Air Force Base) in Arizona leaving only five on strength. Some of the personnel assigned to HMMT-164 gave their opinions and experiences with the old “Phrog” –

“The CH-46 is a safe, reliable and steady platform to fly and was the workhorse of the Marine Corps, many within the squadron are very sad to see it retire shortly, but until that date, it is the jobs of some of the best pilots and maintainers in the Corps to keep these wonderful helicopters in the air and combat ready. The mission role has reduced of late but anything can happen as with the wildfires in Santa Ana during 2014 when all of our helicopters were called into service to help control the spread of the fires that were up on the mountains surrounding of Camp Pendleton. The squadron worked alongside the Fire Department to help contain the spread, something we are all proud of. As our “Phrog” operations slow down, crew and maintainers are at school training on the replacement for the squadron the MV-22B and this is a whole different world to the CH-46E. Once our CH-46s retire, they will either be flown to the Boneyard or go to museums for preservation, especially our green one.”

Of the remaining CH-46s on the ramp, two were wearing special markings – one carrying “high visibility” markings and the other in olive green gloss to commemorate prisoners of war lost during the Vietnam War. To finish our tour we were guided around the crew areas and operations rooms of HMMT-164, furnished with the much loved memorabilia that adorned the walls, shelves, corridors and office desks. This memorabilia was in the process of being removed and archived, ready for the upcoming change of command.

Since our visit on the 29th January 2015, HMMT-164 officially retired on 9th April 2015 with the CH-46E Sea Knight and transitioned to the MV-22B Osprey becoming VMM-164.

AeroResource would like to thank the public affairs team at MCAS Camp Pendleton. We would also like to thank the aircrew and maintainers of HMLA-469, HMLAT-303, and HMLAT-164 for taking the time to answer our questions and showing us around their squadrons.