Singapore Airport Expands to Stay Best in the World

Singapore is proud of its Changi Airport, and rightfully so. It's a destination in and of itself, for locals and tourists alike. In fact, Changi has been named the world's best airport for the sixth year in a row. But it's nearing full capacity. And with robust growth predicted, Changi needs to expand.

Passenger traffic has been growing by an average of 5.7 percent per year over the past decade. In 2017, it grew by 6 percent, to 62.2 million. Full capacity for the airport's four terminals is 85 million. Changi is expected to reach that level within a decade.

This has prompted the Civil Aviation Authority of Singapore (CAAS) to embark on an ambitious expansion effort, known as Changi East. The program includes a three-runway system, a network of tunnels and systems, and a new terminal.

The Third Runway's the Charm

CAAS is adding a third runway by converting an existing military runway to joint civilian/military use. CAAS sponsors MITRE's first research and development center outside of the United States—MITRE Asia Pacific Singapore (MAPS). Via this partnership, MITRE is helping CAAS decide how to get the most possible capacity out of a three-runway system.

"In 2016, CAAS asked us to come up with how best to use the three-runway system," says Koffi Amefia, MITRE's international airspace design and modeling group leader. "They had some options in mind for using three runways. They were interested in 3RIMM [Three Runway Independent Mixed Mode] but didn't know if it was feasible. They wanted us to look into it."

3RIMM squeezes a lot of capacity out of a three-runway system by allowing each of the runways to be used simultaneously for both arrivals and departures. Most runways are used for only one or the other.

In 2017, we developed a plan for 3RIMM at Changi that addressed all anticipated variations for arrivals and departures. The team used computer simulations to create a baseline analysis of airport operations and then designed a model for 3RIMM that could support the most aircraft movements.

"We've worked closely with CAAS's design team to develop the concept," says MITRE's Brett Warden, an aviation systems expert. "They've understood the changes they'll need to make for this to work. Over the past year, we've moved from being aspirational to being more realistic. The additional work we're doing now is validating the concept through simulations."

Good Procedures Make for Good Neighbors

Changi Airport will need new procedures and regulations that support 3RIMM.

The United States is the only country with airports currently operating Triple Independent approaches, so the U.S. Federal Aviation Administration (FAA) is the only agency that has regulations and procedures that support it. We operate the FAA's federally funded research and development center, so we've worked on a lot of airport procedures and regulations.

"We've laid out a list of the issues they'll have to address," Warden says. "Either regulatory changes or making changes to local issues, especially sharing airspace with their military and with neighboring countries. Some of their procedures may have to change."

As a nonprofit company working in the public interest, MITRE cares only about helping our sponsors identify the best solutions for a safer world. So even if CAAS decides not to run 3RIMM, the suggestions we're making will help their three-runway system run efficiently. For example, we've proposed a concept that will allow more aircraft to take off within time limits, which will speed up departures.

"We don't benefit when our sponsors buy any particular system," Warden says. "We advise them that 'you need a system that does X, Y, and Z,' but because we don't sell any systems, there's no hidden agenda. That lets us give our honest opinion."

—by Kathy Chamlee

Photo: MITRE's Camille Shiotsuki and Koffi Amefia discuss how an innovative three-runway configuration could increase capacity at Singapore's Changi Airport.