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Phrog Farewell

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On August 1, the National Air and Space Museum will join with the United States Marine Corps and the National Museum of the Marine Corps to bid adieu to one of the most important American military aircraft of the past 50 years, the Boeing CH-46 Sea Knight, or “Phrog,” as it is almost universally known among Marines. Although often overlooked next to the Vietnam-era Huey in the pantheon of helicopter fame, this aircraft may well have been at the forefront of more American military operations in peace and war than any other. The Phrog, named for its squat, amphibian-like appearance and tendency to bounce when taxiing (the origin of the “ph” is a bit more obscure), has been the unsung hero of Marine Corps operations since June 1966 when squadron HMM-265 began operations in South Vietnam.

A “Phrog” (Boeing-Vertol CH-46E Sea Knight Bureau Number 153369) at the Norfolk Naval Air Station hangars of Marine Corps Reserve Medium Squadron HMM-774. Photo: Roger Connor

The Phrog has been the Corps’ longest serving helicopter by a wide margin and has been most useful in the remote corners of the globe. However, its origins are tied closely to the atomic bomb and superpower conflict. The 1946 atomic tests at Bikini showed that the Marines’ previous way of war—concentrating amphibious forces against defended beaches—was untenable if the enemy had nuclear weapons. Their solution was a strategy known as “vertical envelopment,” to leapfrog the defenses with helicopters and outflank the enemy. The attacking force would be weaker, but it would also be striking where the enemy wasn’t. Coincidentally, this strategy for dealing with the extremes of potential Cold War outcomes proved ideally suited to the proxy wars that occurred on the fringes of the American and Soviet spheres over emerging Communist and anti-colonial insurgencies. The Korean War validated the helicopter’s potential, but it was the British and French experiences in Indochina, Malaya, and Algeria that demonstrated just how critical helicopters were in conflicts where road networks were severely limited.

The Marine Corps pioneered the aerial movement of personnel bypassing enemy strongpoints—a  concept known as “vertical envelopment.” The Marine’s squadron for helicopter development, HMX-1, operated the Piasecki HRP-1 in the late 1940s to develop the doctrine. These HRP-1 “Flying Bananas” are seen performing a public demonstration of vertical envelopment at the 1949 Cleveland Air Races. Photo: National Air and Space Museum | NASM9A02724

The Vertol Corporation, soon to be part of Boeing, manufactured the H-21 used by the U.S. Army and Air Force, as well as the French army, which employed them extensively in Algeria. Based on the Algerian experience, Vertol proposed a new design—the Model 107, which immediately found favor with the Army. This new design utilized turbine engines instead of a reciprocating power plant, giving it greater power in a smaller package. The proven tandem rotor configuration was ideal for accommodating both internal and external loads. By the time the first samples were under production for the Army, the Marines had committed to the replacement of its existing Sikorsky HUS fleet, known as the UH-34 from 1962. In 1961, the Marines embraced the Army version of the Model 107, which the Corps designated the HRB and would become the CH-46 the following year. The Army ultimately decided the Model 107 was too small for their needs and had it redesigned into a considerably larger version, which would soon become known as the CH-47 Chinook.

A CH-46 lands supplies at Khe Sanh during February 1968. Photo: National Archives and Records Administration | 127-GVC-89 A190595

Ultimately, the Marine Corps acquired over 400 CH-46s which fully replaced the UH-34s by the late 1960s. This transition couldn’t have come sooner. The UH-34 had been a vast improvement on its predecessors when it entered service in the mid-1950s, but it struggled heavily in the hot, humid conditions of Southeast Asia, and although the cabin could carry 12 armed troops, it struggled with half that load. Provided it didn’t have to carry too much fuel, the Phrog could carry 17 fully equipped Marines.

CH-46s and an Army CH-47 Chinook (background) support Operation Scotland II on the Demilitarized Zone during September 1968 in the aftermath of the siege of Khe Sanh. The CH-47 program also grew out of experience with Vertol’s Model 107. Photo: National Archives and Records Administration | 127-GVC-89 A192709

The Phrog served admirably in support of Marine combat operations in Vietnam, including some very high profile operations such as the resupply of the besieged Khe Sanh garrison and the evacuation of the U.S. embassy in Saigon as it fell in 1975. However, CH-46 crews suffered heavily. A series of in-flight break ups led to a panicked search for technical solutions. As one of the larger helicopters in service, it was also a juicy target for the enemy—one that had limited defensive firepower and a number of vulnerable systems. Over a third of all Marine CH-46s were lost in Vietnam, with 109 brought down by hostile fire (40% of the Marine helicopters lost to enemy action) and another 50 destroyed by accidents and other causes.

A Phrog jettisons fuel during an emergency extraction west of Da Nang in June 1970. Photo: National Archives and Records Administration | 127-GVC-89 A422841

After Vietnam, the CH-46 continued to serve with the changing tides of American military involvement. Even in peacetime, the Phrog frequently was tasked with evacuations from embassies during periods of unrest and civil war abroad. By the 1970s, the proven Phrog was showing its age and the Marine Corps began looking at new technologies. Ultimately, Bell-Boeing MV-22 Osprey tilt rotor emerged as the solution to the Phrog’s Achilles heel—range. However, while the Osprey underwent an agonizingly slow and plagued development, the CH-46 suddenly began to shoulder a greatly increased burden of operations in the turbulent geopolitical environment as the Cold War drew to a close. Less than 300 airframes had to support demanding trials by fire and the elements in Grenada, Beirut, Operation Desert Storm, Somalia, Haiti, Bosnia, Iraq, and Afghanistan.

One of the more enduring accomplishments of the Phrog that often gets lost with the focus on combat operations, was its starring role in humanitarian and disaster relief efforts. On five continents the Phrog helped deliver countless meals and water to survivors of earthquakes, famines, hurricanes, typhoons, floods, and civil war.

During severe flooding, two U.S. Marine Corps CH-46 Sea Knights are loaded with bags of flour donated by the World Food Program before flying to an aid distribution site on October 21, 2010 near Pano Aqil Cantonment, Pakistan. Photo: Staff Sgt. Kali Gradishar | Department of Defense | 101022-F-0526G-009

Now, as the final CH-46 squadron, HMM-774, begins its conversion to the MV-22, the final examples of this helicopter are finishing out their storied careers of five decades. As a fitting tribute to the legacy of this aerial workhorse, the Marine Corps has set aside one particular Phrog to represent and carry the flag for this type. The chosen Phrog, Navy Bureau Number 153369, is a worthy candidate for the honor. One of its pilots, 1st Lt. Joseph Donovan was awarded a Navy Cross for a rescue under fire in Vietnam during April 1969.

Unfortunately, like nearly all Phrogs, the aircraft records provide an inadequate history of the everyday heroism exhibited by the aircrews and Marines, like Lt. Donovan, that flew on these helicopters. 153369’s recent history is no less distinguished than its Vietnam history. It served in both Iraq and Afghanistan during some of the most intense periods of combat. Between February and September of 2004, it operated with squadron HMM-266 in the Oruzgan province in central Afghanistan. It also operated in Iraq with squadrons HMM-161, HMM-268, and HMM-364 over a three-year period, starting during the height of the “surge.”

The era of the conventional helicopter is beginning to give way to more advanced forms of rotorcraft as the Bell-Boeing MV-22 Osprey (top) replaces the venerable CH-46. Here, both types from the 3rd Marine Aircraft Wing transport Marines to the USS Bonhomme Richard, to prepare for San Francisco Fleet Week in October 2011.Photo: Lance Cpl. Joshua B. Young | Department of Defense | 111003-M-2949Y-002

On August 1, 2015, helicopter 153369 will be added to the collection of the National Museum of the Marine Corps. At the moment, their Quantico, Virginia location is unable to accommodate the airframe. While the Marine Corps Museum creates space, the National Air and Space Museum will display the helicopter at the Steven F. Udvar-Hazy Center in Chantilly, Virginia as a long-term loan. The aircraft is wearing a high-gloss version of its Vietnam paint scheme as a tribute to the type’s original trial by fire and for its central place in Marine operations in Southeast Asia during the Vietnam War.

Purple Foxes retire last 'Phrog'

Bu. No. 153369 will be the flag bearer for the Phrog’s retirement. It is seen here in October 2014 in its new “retro” markings, applied by HMM-364 “Purple Foxes,” who operated this aircraft extensively during the Vietnam War. Photo: Cpl. Owen Kimbrel | Department of Defense | 141029-M-CJ278-111

The delivery flight and public ceremony for 153369’s retirement at the Steven F. Udvar-Hazy Center on Saturday, August 1 at noon, will be the last public showing of an airworthy CH-46 and is the Marine Corps’ formal sunset ceremony for the type. To celebrate the Phrogs’ five decades of service and the complete transition of the Marine’s medium lift capability from CH-46 to MV-22, the event will be open to the public. Visitors will have the opportunity to walk through the 153369, as well as an MV-22 that supports HMX-1, best known for its role in supporting transport of the President.

Have you had experience with the CH-46 Phrog? We’d love to hear your story. Leave us a comment below to share or simply say goodbye to this venerable aircraft.

Roger Connor is a museum specialist in the Aeronautics Department who curates the museum’s drone collection.

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25 thoughts on “Phrog Farewell

  1. From 1970 through 1974, I was in the Navy and served aboard USS Hawkins (DD-873), a WW2 era destroyer. When we were deployed on special ops in the Mediterranean, the sight and sound of the CH-46 meant we were receiving mail and food. These were dropped on our “helo” deck which was designed to accommodate the anti-submarine drone currently at UH. The arrival of the CH-46 was a real morale booster after weeks at sea following Soviet ships around in circles.

  2. Always scared the crap out of me flying in these when I was in the Marine Corps. Once during a storm we were landing on the USS Guadalcanal and the back of the helo was lower than the ship. Luckily the crew noticed it after a bunch of Marines were yelling to pull up. Close call. I preferred flying on the 53’s.

  3. Fair winds, Following Seas and Semper FI my friend… You were an integral part of my young adulthood and my life as a Marine!!! you may be in retirement but will never be phorgotten 😉

    Phrogs Phorever!!!

  4. I was an H-46 crew chief from 1998-2002. In that time I accumulated 700 flight hours. I was stationed in Iwakuni, Japan under Pedro search and rescue (HH-46D), and deployed with HMM 264 (CH-46E) with the 26th MEU on the USS Saipan in 2000. I have several good photos of the Phrogs from that deployment. She was a good, reliable aircraft. Never had any major problems. She’s going to be missed.

  5. I enjoyed your article on the Phrog Farewell. I flew many different helicopters, but, the CH-46 is one of my favorites. I worked as a factory test pilot for Boeing Vertol in Philadelphia from 1966 until early 1970. During that time, I flew many different CH-46s, one being your honored CH-46 BU# 153369. I flew it on two factory test flights (7&9 Mar 67) and again on a visit to MCAF New River, NC with the Marines. I was one of two factory test pilots that taught the USMC Maintenance Test Pilot Course on the CH-46 at MCAF Santa Ana, CA from Oct 69 through Jan 70. Great aircraft that provided a very enjoyable and rewarding experience for me.

  6. I was a crew chief on the phrogs from 1972 to 1991. Over 3000 hours. They were tough birds. In 1973 we were in a 12 plane formation. We were in a three plane formation in the back of the pack. We got too close to -2 and intermeshed rotor blades. We were flying over Okinawa at 1000 ft when we hit. All three of the birds sustained damage. We landed safely, inspected the damage, taped up some holes. We had a another bird bring us three forward blades and three aft blades. After changing blades and a quick tracking check we flew them back to Futema Air Base. I miss flying the most!

  7. I will miss the Phrog! I worked Flight Line with HMM-163 before I even hit basic Aviation School in 1999. That was my first experience with the 46. My “C” school was to fix the T58 which powered the Phrog. I spent from 1999 – 2003 with MALS-36 rebuilding, troubleshooting and testing the T58 for HMM-265 and HMM-262. Semper Fi!

  8. I was a CH-46 flight line mechanic and AO. I flew a little over 200 hours on board. I have found memories flying turf flights and externals at CAX in 29 Palms.

    I remember the first time I completed a work order and saw the bird fly after I had worked on it I was exhilarated. I can still remember the smells of jet fuel and grease.

  9. I served as a crew chief on Phrogs for more than 10 years. I was with HMM-163, HMM-764, and HMM-166. As a member of HMM-163, I participated in the longest amphibious assault in Marine Corps history as we inserted into Afghanistan following September 11th. Great experiences on these magnificent machines. What a glorious aircraft. Looking back, I wouldn’t have wanted to fly on anything else. Semper Fly! Frogs Phorever!

  10. Was a Huey crew chief with VMO-6 at Quang Tri, ’67-’69. HMM 161 and 262 replaced the H-34 squadron, maybe HMM-163 or 361. I don’t remember now. Flew in -46s when we had to recover birds in the field, when leaving my Huey at Khe Sanh a few times when we went bingo fuel after staying on station covering grunts too long into the night, and when we had to make “off base conditional landings in hostile jungle territory due to battle damage” (got shot down). That was when they looked best.

  11. I was in Bravo Co., 3rd Recon in Khe Sanh from 6/67 until 4/68. There was nothing more beautiful than a 46 lumbering into a contested landing zone to pull our butts out of the fire. The 46 was amazing, only outdone by her pilots and crew men. God bless them all!

  12. I was a crew chief on the CH46E 154009 from 1989-1992 with HMM-261 during operations Sharp Edge, in Liberia and Desert Shield/Storm. I loved every minute of my experience with this marvelous bird.

  13. CH-46: Phrogs Phorever. HC-8, Det 6 SarDogs. USS Saipan (LHA-2), Mediterranean Ops 1996. Stood the watch and loved flying this crazy contraption. I fly airliners now commercially, and flew a lot of fixed wing turboprops in the Navy. The most fun I’ve ever had flying was working this machine through the air, down low and slow. Some sights will never vanish from sight in my mind, like scaring up a school of huge flying fish off North Carolina and seeing them glide feet below you in the sunlight. Or the adrenaline that came from sliding off the deck edge at night on NVDs. Or the most intense moments ever airborne, when our crew slogged out to the USS Lamoore County, an LST that was a rocking and heaving on a dark and stormy night, to medevac a wounded sailor to a hospital…found out later he made it. It’s sad to see a fine work horse put out to pasture. But as Mr. Spock said, for all things there is a season and must end, or change. It is the way of things. Whatever it is, I miss flying that damned thing and the camaraderie of the fine people I served with.

  14. On the origin of the “phrog” spelling: Viewed head-on, the H-46 definitely looks like a big green frog squatting on its haunches (the stub wings) on a river bank, perhaps wearing one of those comical propeller beanies. I was an H-46 pilot in Vietnam during ’69 – ’70 with HMM-161. When I joined the unit, it was based at Phu Bai in northern I Corps. My understanding at the time, per our unofficial squadron patch of “Phrog Phlyers”, was that the spelling was a reference to the standard practice of transliterating Vietnamese place names on maps, etc. that contained a hard ‘F’ sound into the Roman alphabet equivalent of ‘Ph’ (e.g. Phu Bai, Phu Ket, Dien bien phu, etc.). Phrogs Phorever!

  15. To add a few details to the otherwise excellent article above: As a Vietnam era CH-46D pilot, I am certain that the NATOPS (operators’ manual) for the CH-46D of that period specified a passenger capability of twenty combat equipped Marines rather than the seventeen cited in the article. In addition, the aircraft was designed to carry internal cargo, to include a single USMC M422-A1 light utility vehicle (mini jeep) and attached trailer. While I don’t believe I ever carried that particular load, I saw that demonstrated at a number of different airshows stateside. Further, the CH-46 was, and probably still is, the most mechanically advanced design of any utility helo ever used by the U.S. military and in that respect is still ahead of even the current UH-60 Blackhawk, which I have also flown. The Phrog had power blade fold and blade tip lights for shipboard operations together with what I believe was the first-ever operational rotor blade anti-ice system, making it the first truly all-weather helo. Additionally, its innovative fore and aft swiveling rotor heads that positioned themselves based on air speed in order to keep the fuselage parallel to the ground in all flight modes, thus improving pilot visibility during landing approach and touchdown, were probably unique for that day (this replaced the manually-selectable “hover aft” system of earlier models that served the same purpose, but was activated only for landing and touchdown). The actuators for this system (and/or possibly the fore and aft rotor head swash plates) were coupled to a trim wheel on the cockpit center console enabling pilots to manually adjust fore and aft CG via rotor pitch and rotor head position for a level hover when carrying internal cargo. We never received training on that particular piece of equipment but using it probably saved my life and those of my crew on one particular occasion (a story for another time). Of all the different helos I’ve flown, the Phrog is definitely head and shoulders above the rest! Phrogs Phorever!

  16. I was never in the Marines, but I spent the better part of 1967 – 1969 with Squadrons HMM 164, 165 and 265 at Jacksonville, in the Caribbean (3 months on the Boxer) and Vietnam (7 months at Marble Mt., on the LPH-10 Tripoli, at Quang Tri and Phu Bia) as a young GE Tech Rep. The “D’s” were great. I served with the Marines and yes I know the strengths and weaknesses of this great bird well. Many of those guys allowed me to fly them and I will be forever grateful and never forget for those experiences. I am ever so sorry to have missed the Phrog Farewell and the opportunity to have perhaps seen some friendly faces once again.

  17. Pingback: AirplaneGeeks 362 The Doctor is in… Talking About Medical Issues | Airplane Geeks Podcast

  18. An ‘Oldie but a Goodie’!!!

    The long and glorious 50(+) years of service by the ‘Phrog’ was due not only to the wonderfully reliable and functional design of the airframe (thank you Mr Piasecki and Boeing), but also
    (1) Very good and timely decisions by the Life Cycle Managment leadership in the USMC and NAVAIR (Three Service Life Assessment Programs and three Service Life Extension Programs…along with a digital fuel control / engine gas-train upgrade in the mid-2000’s) and
    (2) Long, hard hours by the thousands of personnel who provided care and feeding of the helicopter.

    As I celebrate ‘my’ 50th birthday, I am humbled by the dedication and service of the men and women with whom I served with while a CH-46 pilot.

    Phrogs Phorever!!!

  19. I flew the CH-46 1000 combat hours,1100 combat missions, in 1969 with HMM 262. Most these flights were out of Quang Tri in Northern I Corps. Have many experiences with a shot up Phrog getting me safely home. It was a phenomenal aircraft. HMM 262 and HMM161 were supporting an entire Marine Division.

    I am happy to report that I became the Commanding Officer of HMM 161 ten years later.

    Just attended a reunion with HMM 262 in Pensacola July 2015 and will attend with HMM 161 in Charleston in Oct.

  20. I got my fifth choice out of fight school. CH-46E’s east coast. After 10 years on active duty flying the Phrog out of MCAS New River, I transitioned to the Reserves. I have spent the last 8 years flying her with HMM-774 in Norfolk. I am honored to say that my final flight as a USMC aviator was testing 153369, in advance of her delivery to the museum. Farewell old girl, thanks for always bringing me home…

  21. I enjoyed the story..brought back a lot of great memories. Spent my H-46 career in HMM-161, HMM-164, and SAR at MCAS Iwakuni. I especially cherish my transition in the H46 community at HMT301 at MCAS Tustin and my time in HMM-161 since all of the instructors and senior folks were Vietnam veterans who shared lots of invaluable experience. Would love to hear from any teammates. Semper fi.

  22. I am old 3d artist doing addons for ARMA3 sim game, currently working on CH46 family helicopter. I am looking for CH-46 Flight Manual to create as much realistic flight model as possible as the game employs decent FM engine, straight from mil simulators. Could some of you help me with this, please ?

    Here is BIS forum topic regarding the project: https://forums.bistudio.com/topic/187119-ch-46-knight/

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