The helicopter caused a leap forward in the concept of amphibious assault operations.
The title of being the first ship designed and commissioned according to this revolutionary
concept belongs to the Iwo Jima-class. The USA used seven ships of this class successfully
in many important operations between 1961 and 2002. Now we are investigating the Iwo
Jima-class, a true amphibious assault ship legend.
Please don't forget to subscribe to our channel, before we start and give us a thumbs up if
you like our video. To be notified of our new video, please click the bell button.
The Iwo Jima-class landing platform helicopters, shortly LPH, were the first amphibious assault
ships designed and built as dedicated helicopter carriers. However, it was not easy for the
USA to decide to use such type of ship. Since the Second World War, military planners
had been aware that helicopters offer great opportunities. However, they did not know
exactly how to use them effectively. Studies were progressing slowly.
Because with the end of the Second World War, the USA had been in an optimistic mood and
was not expecting a new major convetional war.
Washington believed that it could resolve all disputes with the advantage of being the
only owner of the atomic bomb. Nevertheless, the US Marine Corps made significant
trials about helicopters in the second half of the 1940s.
On May 1, 1948, five HO3S-1 helicopters, took-off from the aircraft carrier USS Palau, transported
66 marines and their necessary equipment to land.
The four-seat HO3S-1s had to do 35 flights for this job.
This exercise, called Operation Packard II proved that the helicopters are highly useful
for the amphibious assault vehicles. The marines called this type of operation
as "vertical envelopment" instead of "air mobility" or "air assault".
However, even this success was not enough for the Pentagon to be interested in this
new concept. But two years later, because of the Korean
War, the US generals faced the truth. The atomic bomb could not prevent the outbreak
of a major conventional war. Besides, it was not possible to use this weapon under all
conditions. On September 13, 1951, the US Marine Corps
used the helicopters to supply its battalion with 8,550 kilograms of supplies and evacuate
74 wounded troops. Throughout the war, the helicopters had proven over and over again
how effective it were. Thus, the USA decided to convert the former
escort carrier USS Thetis Bay to helicopter carrier, in 1955. After a while, however,
converted aircraft carriers proved to be inefficient for the job.
So, in 1958 the USA approved the construction of the Iwo Jima-class LPHs, designed delicately
for this mission. The first ship of the class, USS Iwo Jima was laid down in 1959, launched
in 1960, and commissioned in 1961. To increase the internal volume and to reduce
the costs, the hull was preferred similar to a commercial ship with large width and
freeboard. At the earliest stage of the design, the ship
had a fin stabilizer. However, it was abandoned to cut costs. Although this sacrifice saved
the money, it caused significant problems. The seakeeping ability of the Iwo Jima-class
was low. Many crew members were suffering from seasickness when the sea conditions deteriorated
even a little. To crown it all the propulsion system was causing strong vibrations over
speeds of 21 knots. Even, some compartments of the ship were becoming almost uninhabitable,
because of this. Originally the ship was planned to have a two-shaft propulsion system. However,
again to save money, the number of shafts was reduced to one.
The ship had a 70-meter-long hangar. The flight deck was 183.7 metres long and
31.7 metres wide. Up to seven helicopters could operate at the
same time. Naturally, over the years, different types of helicopters had been deployed on
the Iwo Jima-class LPHs. In their last years, they normally carried
an air group consisted of four CH-53, ten CH-46, two UH-1, and six AH-1 helicopters.
In some mission, up to four AV-8 Harriers were also temporarily being stationed onboard.
The elevators of the USS Iwo Jima, USS Okinawa, USS New Orleans and USS Inchon had a capacity
of 23.32 tons. Elevators with a capacity of 19.6 tons were
preferred in the other two ships. These elevators were foldable, for passage
of the Panama Canal. Also, there were two small ammunition elevators
with the capacity 7 tons. Although the Iwo Jima-class was designed purely
for vertical envelopment operations, it also carried two Landing Craft Personnel, Large.
These LPHs had the operating room, X-ray room, hospital ward, isolation ward, laboratory,
pharmacy, dental room, and medical storeroom. Their medical facilities had 155-bed capacity.
The complement was 902-person. The Iwo Jima-class could carry 2090 marines. They had a length
of nearly 184 meters, a beam of 32 metres, and a draught of 10 metres. Fully loaded displacement
of these ship was about 18,800 tons. Two 600 psi Babcock & Wilcox boilers and one De Laval/General
Electric/Westinghouse turbine produced 23,000 horsepower. The maximum speed of 23 knots.
The ship can reach the range of 18,520 kilometres with the economical speed of 20 knots. The
Iwo Jima-class could carry 20 CH-46 Sea Knight or 11 CH-53 Stallion helicopters. When commissioned,
each vessel had four 76mm twin barreled guns. Befor they were decomissioned, these guns
were reduced to two. From the beginning of the 1970s, the Iwo Jima-class ships were equipped
with two octuple RIM-7 Sea Sparrow air defence missile launchers. In the 1980s, two Phalanx
close-in weapon systems were also installed. These LPHs had the AN/SPS-65 air search, AN/SPS-40E
air/surface search, AN/SPS-67(V)1 surface search, AN/SPS-64(V)9 navigation, SPN-35A
and SPN-43B carrier controlled approach, and Mark-115 fire control radars.
As soon as Iwo Jima-class LPHs commissioned, they began the part in the major USA operations.
USS Iwo Jima and USS Okinawa of this class were in the Caribbean during the Cuban Missile
Crisis of 1962 for the possible invasion of the island.
These ships played an active role in the Vietnam War.
In 1965, USS Iwo Jima joined in Operation Starlite in Vietnam.
During the operation, the H-34 helicopters of VMM-163 squadron, took-off from the ship,
conducted many search-and-destroy raids. She had supported more than 20 search-and-destroy
operations until late 1966. Also, evacuation and surgical teams of USS
Iwo Jima save the lives of many wounded US troops.
In 1967, off the coast of Vietnam, USS Okinawa deployed as a mobile base performed many important
vertical envelopment operations. During the war, the busiest ship of its class
was the USS Tripoli. She served on three tours in Vietnam. The USS Tripoli had participated
in eight amphibious operations in her first tour alone.
USS Okinawa was there in the final phase that ended the war.
She participated in Operation Eagle Pull, the evacuation of Phnom Penh, Cambodia as
well as Operation Frequent Wind, the evacuation of Saigon, Vietnam and save many lives.
While her sisters fought in Vietnam, USS Guam was busy with another important task.
The Pentagon had approved to test the Sea Control Ship concept of Admiral Elmo Zumwalt.
The concept was including to use the small escort aircraft carriers, providing air support
for convoys. Thus, in case of war, the US Navy could have
used its supercarriers against Soviet Navy instead of convoy escort duty.
USS Guam was the test platform of the concept. In 1972, the ship began extensive trials with
AV-8A Harrier fighters and Sea King anti-submarine warfare helicopters.
Yet, the Pentagon did not find the concept feasible, and USS Guam went back to her old
job. In 1982, USS Tripoli was the test platform
for the XV-15 experimental tilt-rotor aircraft. This trial was the important step that paved
to the way for the V-22 Osprey. In the early 1980s, first USS Guam and later
USS Iwo Jima operated off the Lebanese coast. Their marines of them disembarked to take
position around Beirut International Airport. But this US mission tragically ended on October
23, 1983, when an attack on the Marine's barracks caused the losing 241 US servicemen's life
and wounded a further 60. USS Guam served as the flagship for Operation
Urgent Fury, in the invasion of Grenada. In 1984, the Tanker War started as a new phase
of the Iran Iraq War. After a while, this endangered the oil shipment to the Western
world through the Persian Gulf. So, in 1987, the USA started Operation Earnest Will to
provide military protection of Kuwaiti-owned tankers from Iranian attacks.
As a part of this operation, in 1987, USS Guadalcanal was leading minesweeping operations
in the Persian Gulf. On September 21, 1987, the helicopters of
USS Jarret frigate reported that the Iranian ship Iran Ajr was laying mines in the shipping
lines. The US Navy SEALs disembarked from helicopters
of USS Guadalcanal attacked, boarded and captured the ship. Five days later, they scuttled Iran
Ajr in international waters. While the Iwo Jima-class ships carried out
important missions during the 1991 Gulf War, they also faced some critical misfortunes.
For example, as part of the buildup for Operation Desert Shield, the US Navy had deployed USS
Iwo Jima in the Persian Gulf, in October 1990. The ship developed a leak in a steam valve
which supplied steam to an auxiliary electrical generator. For repairment, she docked in Bahrain.
Soon after, USS Iwo Jima left the port to rejoin the fleet. However, due to the conditions
of the war, the repairment finished prematurely without necessary inspections. The valve began
to leak again and caused a lethal accident. During the war, as the flagship for mine countermeasures
operations, USS Tripoli was serving in the northern Persian Gulf.
On February 18, 1991, she hit an Iraqi naval mine on her starboard bow. The explosion ripped
about 5x6 metres hole in the hull. The crew managed to stabilize the ship, after 20 hours
of work. But USS Tripoli could not resume her duty. She docked in Bahrain.
After 30 days of repairs, the ship returned to the Persian Gulf to continue minesweeping
operation. USS Guam, another Iwo Jima-class ship stationed
in the region while the Gulf War continued, was urgently sent to Somalia after the rebels
entered the capital Mogadishu. Along with the USS Trenton, she evacuated
282 people in total, including ambassadors of the USA as well as Germany, Kuwait, Nigeria,
Oman, Qatar, Sudan, Turkey, the United Arab Emirates, the UK, and the USSR.
On December 3, 1992, USS Tripoli conducted the first landing operation of Operation Restore
Hope, in Somalia and her Marines secured the airport and seaports in Mogadishu.
The Iwo Jima-class had also played important roles in the US space rocket programmes. These
ships recovered many astronauts landing in the sea before the space shuttles.
For example, In 1970, USS Iwo Jima was the flagship of Task Force 130 that waited for
the famous Apollo 13 spaceship's astronauts. According to an article, published in 2012,
by USNI News, the Reagan Administration offered the USS Iwo Jima to the British government,
in case HMS Hermes or HMS Invincible, had been out of war during the 1982 Falklands
War. In 1992, USS Okinawa became the first decommissioned
ship of the class. The last Iwo Jima-class LPH, USS Inchon was
decommissioned, ten years later. USS Guam, USS Okinawa, USS Inchon, USS Guadalcanal,
and USS New Orleans were sunk as target ships in 2001, 2002, 2004, 2005, and 2010 respectively.
For more than 40 years, Iwo Jima-class ships had undertaken important roles in protecting
the US overseas interests. They played a leading role in accepting the helicopters as a natural
part of amphibious assault operations and became the reliable floating bases of the
US Marine Corps. Thus the Iwo Jima-class deserved to become an unforgettable legend.
Thanks for watching our video. And please don't forget to subscribe to our channel and
give us a thumbs up if you like our video. To be notified of our new video, please click
the bell button.