The flight from the city-state to Newark Airport can take up to 18 hours and 45 minutes under normal weather conditions, but the pilots will have something in reserve in an aircraft capable of flying more than 20 hours non-stop.
The inaugural flight, SQ22, departed Singapore on-time just before midnight Thursday night, embarking on its historic journey for the first time on the over 9,500 mile route to New Jersey.
Campbell Wilson, its senior vice president of sales and marketing, said the Airbus A350-900ULR, which was delivered two weeks ago, consumes 25 percent less fuel than an older generation aircraft of the same size.
Despite the rise in oil prices, several big airlines hope to secure the market of ultra-long-haul flights by using fuel-efficient planes.
While the airline's business class on board the ULR Airbus remains the same as its shorter-range A350s, Singapore has tweaked its premium economy seats for the long seating time. Don't be! Singapore Airlines will offer business class passengers two meals, giving passengers the option as to when they eat.
The marathon flight had no standard economy seats, only so-called "economy comfort" and business class.
Singapore Airlines (SIA) has re-launched the service for the first time in five years as the flight was originally too expensive.
It also has fewer passengers onboard. It has become the world's longest direct passenger flight.
Premium economy fares will get three meals at fixed times, with refreshments in between.
The Singapore Airlines flight had been specially configured to seat 161 passengers for the service between the two global financial hubs. Even after 17 hours flying on 4 hours rest they have remained cheerful and helpful.
The flight last took place in 2013 with an A340-500. It said there was demand for non-stop services which help cut traveling times compared with flights that have a stopover. The airline flew the 16,700-km route earlier, but ended it in 2013.
Speaking of time, those aboard the plane will have a lot of it on their hands.
The cabin of the A350-900ULR has higher-than-normal ceilings, larger windows and lighting created to reduce jet lag and dining options included dishes the airline said were specifically selected to promote well-being in the skies, with organic dishes on the menu.
Mr Thomas says it's been proven over and over again that people want to fly non-stop, "so these sorts of aeroplanes are set to gain terrific momentum".
"Qantas' flight from Perth to London is seeing a load factor in economy of 92% - and in premium it's 94%".
The route from Singapore to Newark is over 9,500 miles, making it the longest in the world.