Aside from the wartime requirements of the 1940s, the development of specialized cargo operations took a little longer. Unstable lift / lift (Lo / Lo) techniques for vehicles that were still in use until the 1960s. They were carried in conventional ships, often on top of other (heavier) cargo. Carrying capacity was low, handling was slow and the risk of damage was high.

In the 1960s, ramps began to be included in ship designs. In 1965, MOL launched the so-called Oppama Maru truck on the market. It was capable of carrying 1,200 vehicles and 15,000 tons of wheat or grain when the mobile car ramps were raised. In fact, it had five interior decks and six tiers. The vehicles were loaded using central ramps, which increased the processing speed from fifteen units per hour to one hundred.

Starting with multipurpose ships in 1970, ScanAustrals switched to ConRo in 1972, building five units of 22,000 dwt, all of which had an inclined stern ramp. One of them, the Tricolor, still exists, as do (some) of his contemporaries. Known as Cape Diamond since 1985, it was still listed at the end of 2020 as part of the US Maritime Administration’s Ready Reserve Force.

Prior to her public service, Cape Diamond was part of Crowley’s fleet. This carrier has pioneered the provision of the full range of deep sea Ro / Ro services using services other than ConRo. In 1971, he initiated Ro / Ro freight services between the ports of Florida, the US Persian Gulf and San Juan de Puerto Rico. Two years later, Compatriot Matson Navigation opened Ro / Ro service between the US West Coast and Hawaii.

Slowly but surely, Ro / Ro transport has come to be seen as a very suitable alternative to traditional beam transport methods.

Investment in new Ro / Ro properties peaked in the late 1970s when they became popular in markets where port capacity was limited. The adoption of the concept was particularly noticeable for trade in (West) Africa and the Middle East.

Although these vessels and their successors were described as deep-sea or conventional Ro / Ro, they were not designed to carry one particular type of cargo. This is more true for shipping operators, be it passenger transportation, trucks or trailers, escorted or unaccompanied cargo. By and large, they had the ability to carry other goods as well.

Although consolidation of bulk consignments no longer exists, the regularity of sea transport required for the transport of bulk cargo has found a natural partnership with containers and / or bulk cargo. For multipurpose operator Ro / Ro, it does not always happen that self-propelled cargo is the leading element. They often add additional cargo to container shipments.

With the improvement of onshore facilities for Ro / Ro Bulk Service, experts have influenced the deep sea Ro / Ro cargo segment in both containers and cars / trucks (PCTC) or vehicles. Containers received what used to be regular / bulk, PCTC – cars and heavier units.