SINGAPORE – When Hurricane Katrina pummeled the US states of Louisiana and Mississippi 12 years ago, four Chinook helicopters and 45 personnel from the Republic of Singapore Air Force's (RSAF) Texas-based training detachment took to the air to help transport evacuees to safety and conduct search and rescue missions.

The RSAF will be lending a helping hand to the US authorities again this week, after President Donald Trump accepted Prime Minister Lee Hsien Loong's offer to deploy Singapore's CH-47 helicopters from its Peace Prairie detachment in Grand Prairie, Texas, for disaster relief operations.

Mr Lee called Mr Trump on Tuesday (Aug 29) night to express concern and sympathies as Hurricane Harvey continued to wreak havoc across Texas. At least 30 people have died as a result of the massive storm, with damages expected to reach US$42 billion (S$57 billion).

"President Trump thanked Prime Minister Lee for his condolences and offer of assistance to support search and rescue operations, including the use of a Singaporean Air Force Chinook helicopter detachment that trains with the Texas Air National Guard.  President Trump also thanked Prime Minister Lee for Singapore's support for the USS John S. McCain search, rescue, and recovery efforts," the White House said in a statement.

According to Singapore's Ministry of Defence, the RSAF’s helicopters will be able to airlift troops and evacuees, as well as transport supplies to where they are needed the most. They are expected to commence relief operations on Wednesday.

During the relief operations for Hurricane Katrina, the RSAF assisted the US authorities with various missions ranging from relocating evacuees to transporting boats to facilitate search and rescue efforts.

The four helicopters flew more than 80 sorties, during which they helped evacuate hundreds of victims stranded by flood waters and rescued stragglers in the New Orleans area.

The RSAF personnel and helicopters also helped to prevent further flooding of the city of New Orleans by airlifting sandbags and dropping them into portions of the levees broken by the hurricane.

Hurricane Katrina, deemed one of the worst natural disasters in US history, tore through the southern states, killing 1,800 people and damaged countless of homes. It also caused the regional economy to lose US$118 billion (S$159.8 billion).

In a letter to then-US President George W Bush in 2005, PM Lee wrote: ''America has always been generous in helping others in their time of need. Singapore is happy to reciprocate in a small way by participating in your efforts to save lives and restore normality to your people."