President Duterte is expected to inaugurate on Tuesday the much-delayed Communication, Navigation, Surveillance/Air Traffic Management (CNS/ATM) system at the Civil Aviation Authority of the Philippines (Caap) compound in Pasay City.
This P13-billion project is a much-touted next-generation communication and air-traffic infrastructure that promises to end air-traffic congestion in Manila.
Transportation Secretary Arthur P. Tugade, Caap Director General Capt. Jim Sydiongco and Manila International Airport Authority General Manager Ed Moreal would be on hand to present to the President the official imprimatur to put the system in operation.
The state-of-the-art satellite-linked system took 10 years to build. It was first conceived and approved in 2007, under the stewardship of the late Capt. Jake Ortega, chief of the defunct Air Transportation Office, forerunner of Caap.
Sydiongco earlier said the agency has trained hundreds of new air- traffic controllers to augment veteran air-traffic controllers to operate the new system.
Attempts by the BusinessMirror to interview Caap officials to get more details on how the new system works proved futile although understandable. They are reportedly under strict orders not speak to the media so as not to overshadow Tugade and Sydiongco and other ranking officials until after the launch.
The chief of Air Traffic Services, Antonio Gonzales, when asked to be interviewed, hem and hawed until he promised this reporter that he will provide a PowerPoint presentation stored on a flash drive. When this reporter came back at the appointed hour to retrieve the flash drive, I was told that the official was in a meeting.
Indeed, officials of the Caap have been having constant dialogues with other officials involved in the projects, including those from the Japan International Cooperation Agency who provided the ¥22-million (P9.4- million) initial capital.
Caap officials are also in constant touch with officials from Thales Group, a French company that specializes and builds electrical systems and provides services for the aerospace, defense, transportation and security markets.
Former Caap Deputy Director General Willy Borja, a 40-year veteran air-traffic controller, agreed to explain in layman’s language how the system works.
Basically, two major components make up the structure, the talking part, or “communication,” and the other is managing the airplanes so they follow an orderly flow in the sky.
For several decades since the advent of commercial aviation, pilots and controllers talk to one another on radio by means of very high frequency (VHF) band of the electronic spectrum.
The frequencies assigned for commercial and military use, including air-traffic control (ATC), are high frequency, VHF and ultra-high frequency.
These frequencies, however, have limitations. The voice “deteriorate” over long-distances and turns wavy and almost incomprehensible when the airplanes are beyond the horizon or out of the line of sight, usually beyond 250 miles, the maximum reach of long-range radar (Loran). This area is called the oceanic airspace.
Think of the dying HAL, the talking computer in the sci-fi movie, 2001: A Space Odyssey. HAL’s voice sounds syrupy and garbled, as if coming out of a very long tube, until it fades completely as the “life” was snatched out of him (it?).
Bad weather, such as thunderstorms and lightning, also disrupt their radio signals.
For safety and security reasons, ATC must always know an airplane’s whereabouts and they are followed from takeoff to landing at their destination by various means of communication, Borja said.
“Since CNS depends on satellite signals, voice communications are crisps and not subjected to the vagaries of weather or distance,” he said.
It is when airplanes are beyond the horizon, or when more than 250 miles out from their point of origin that CNS employs the Controller-Pilot Data Link. It is communication by digital means, performed through computers.
Here, pilots communicate with the ATC by sending, no longer voice signals, but short messaging system (SMS) or “texting.”
The pilot could either choose from a menu or ready-made conversations, request, emergency messages, or he could simply compose or “text” a new message.
“This SMS could be effective as far as 1,400 kilometers away, up to the limits of our Flight Information Region [FIR], near Guam to the East,” according to Borja. He said the FIR is the area where the Philippines ATC exercises control over their specific air traffic.
The country’s FIR is like a huge rectangle encompassing the whole Philippines. All countries with an active air-traffic control system have their own FIR provided under the International Civil Aviation Organization.
“FIR delineates the limits of our air-traffic control to the northeast adjacent to China’s FIR; to the north, adjacent to Japan; to the northeast, to Taiwan; to the west adjacent to Vietnam; to the southwest to Malaysia; to the south adjacent to Malaysia and Indonesia,” Borja said.
How about navigation? Previously, airplanes follow tracks, which are invisible “highways” in the sky. These tracks are defined by navigational aids, such as the nondirectional beacon distance-measuring equipment (VOR or DMC). Airplanes navigate by tracking from one navaid to another. However, these navaids also have limitation because they lose their signals over the horizon.
The new system that will replace the VOR and other navigational aids is called Performance Based Navigation (PBN). It provides pilot their location in the sky by means of satellite, whose signals are received by means of a compatible equipment in the cockpit.
“The pilot no longer relies on land-based navaids but by the coordinates given by satellite signals,” Borja said, adding the PBN is actually navigation by means of satellite. The signals are broadcasted by the World Geological Survey.
The compatible equipment installed in modern cockpits is called RNAV, or Area Navigation, generally referring to navigation without the need for going from one navaid to another. GPS and Loran are two versions of RNAV, but the original was just a computer that used waypoints (distance and bearing offsets) from existing VORs and/or DMEs.
By international agreement, airports that are basically large and medium hubs, plus a few other busy facilities, will install the broadest range of PBN services.
Ten radar sites have been constructed on top of existing ones to complement the CNS/ATM’s coverage of the entire Philippine FIR. These radars are in Davao, Iloilo, Zamboanga, Cebu, Ninoy Aquino International Airport (Naia), Laoag, Clark, Subic, Pasuquin and maybe Kalibo. In all, they will provide about 98-percent coverage of the entire FIR.
In a previous interview, Sydiongco said the CNS/ATM would “greatly enhance” the tracking and billing of all overflights, as well as international and domestic flights, from which the Caap derives its air-navigation charges (ANCs). About 85 percent to 90 percent of the Caap’s income is from the ANCs.
The CNS/ATM would enhance safety in the sky because of the constant monitoring by ATC, but would it be the magic bullet to solve the congestion?
“Since airplanes would no longer go from one navaid to another but directly fly from the point of departure to destination, it seems there would be faster ‘turnover’ at the airport of destination or at the Naia in our case,” Sydiongco said.
Borja said it seems not to be the case. He added that at the moment, Naia has limited “absorptive” capacity of 40 events per hour.
“No matter how fast aircraft are coming, they would still be separated by five minutes, not three minutes, because the Naia would not be able to clear landing aircraft as fast as needed, to enable the succeeding plane to land at once. Hence the 40 aircraft limitations per hour,” he said.
The solution is to finish the rapid exit taxiway (RET) that is now under construction. RET is constructed slightly angled to the runway, enabling landing planes to exit at a fast clip. Old taxiway designs are at 90 degree angle so that planes had to fully stop before turning to intercept it.
Monreal said the new RET would be finish sometime this year. “In both instances, air-traffic controllers would be able to close the gap between take-off and land, thus reducing the time intervals, which would mean less air congestions.”
He added two previous RET on runway 06-24 were designed for smaller airplanes, such as the A219 or A320 and B737.
“The new RET is for larger aircraft, such as the A330, A340 and A350, including B777, B747, A380 and above,” Monreal said.
But even if the high-speed taxiway is in place, the Naia would still be hobbled by the need to extend the distance between airplanes on the runway and those on the taxiway.
Since the Naia runways were designed in the 1960s, when there were no B747 or Airbus 380 planes on the horizon, so the distance between the runway and taxiway are narrower.
Today, when an A380 takeoff or land at the Naia, all other airplanes are held on the ground. This is to prevent the wingtips of large taxiing aircraft from touching the A380.