Battle of Wits at RPVE

July 14, 2009

Caticlan airport operations is testing CAAP's resolved in dealing with flight safety standard issues and FAA rating upgrade against demand of airlines for some leeway. But can world standard be safely compromised?

Caticlan airport has a runway length of 950 meters. According to ICAO Aerodome standards, only aircraft with a critical rating of 2B should be allowed to use the airport. Of the four domestic scheduled operators Philippine Airlines, Cebu Pacific Seair and Zest Airways, only Seair operates according to the world standard.

The airline utilizes a smaller Dornier 328 plane which seats 32 passengers and 3 crews. Nick Gitsis, Seair Director and 328 pilot previously said two years ago that its aircraft is the most appropriate equipment to fly for Caticlan which stand was adopted by CAAP recently.

All other operators uses 2C equipments which has an operational safety requirement of 1,200 meters to operate without restriction.

So far, Cebu Pacific, Philippine Airlines and Zest Air safely operates at the airport with restricted weight limit. That means operating at the airport with less than a full load around 40-45 passengers depending on weather conditions and fuel load. However, it has been shown repeatedly that airlines usually violate this restriction under the regulators nose and no penalty was ever handed down to date.

Zest Airways operates 60-seater Xian MA60 planes, PAL Express 50-seater Bombardier Q300s, and Cebu Pacific 72-seater ATR72-500s. Although it was Zest Air that suffered landing misfortune twice due to its pilot error. Results of the investigation was not reported to the public but its factors were recently incorporated in coming out with the recommendation.

The biggest aircraft operating in Caticlan is ATR 72-500 of Cebu Pacific which normally carry two-thirds of its seat capacity. The basic landing field lenght of ATR 72 is 1,048 meters (MLW,FAR rules). At 18,000 kg. operating envelope, that is barely enough for the 900 meter runway.

However, CAAP's amendment of its AIP shortening the usable runway length and restricted approach and departure procedure of the airport sealed all other airline's aircraft operating envelope.

The runway field length for runway 06 was reduced to 825 meters, while runway 24 was reduced to 875 meters. It meant runway-end marks were moved further inside from actual runway end. From the above reference, that means Cebu Pacific will need to shed another 500 kgs. equivalent to 5 less passenger loads to safely stop at the 825 meter mark otherwise it will be classified as a landing overran even if it is still within the 950 meter runway.

From PAL, CEB and ZEST operational standpoint, that could still be doable as they can still carry at least 40 passengers but John Slaughter's recommendation to use unidirectional landing and take-off, which was adopted by CAAP Executive Director Ruben Ciron sealed the airlines operational fate to fly at the airport.

The approach and departure procedure calls it to land at runway 06 and depart at runway 24 rationally to avoid the 46-meter hill obstruction 800 meters away at the end of runway 24. Airline operators never considered it a cause for concern for departure other than for landing maneuvers.

The AIP requirement on vertical distance of at least 50 feet above the top of the hill when landing or taking off at Caticlan Airport were apparently made taking into consideration the operations of BAE-146 jets of Zest Air which it no longer operates. The new AIP failed to take into account that even if 2C aircraft types were employed, a lighter load will make the plane climb faster and lands shorter says one airline representative, which argument among others is the basis for their request for reconsideration.

Previously, the airlines’ pilots had been given the discretion to land and take off in either direction taking account wind speed, their expertise and familiarity as well as their aircraft's operational capabilities. Sadly for Zest Air, its pilot approached the runway too high.

The southwest monsoon season (a weather condition where the wind blows from southwest direction, usually starting June to October) doesn't help the airlines cause either as this requires landing on a tailwind. With the wind direction CAAP doesn't take chances on its limited runway unless airlines signed a disclaimer against its liability.

This condition effectively closes Caticlan airport to larger-size aircraft which left Southeast Asian Airlines as the lone carrier still allowed to fly with no restrictions. Affected airlines cannot use the airport until October when northwest monsoon begins and landing at runway 06 more ideal.

Industry sources however said that landing on runway 06 is still possible in the morning for larger aircraft with current weight restrictions where wind blows below 10 knots but they have to land usually before 9 AM as the wind picks up speed after that time making tail landing more difficult as it require more runway length to stop safely.

The most likely candidate that would be allowed to use the airport with 06 tail landing would be the Q300 plane of Philippine Airlines while the least to be allowed is ATR72 of Cebu Pacific which would probably have to shed more weights roughly equivalent to at least 1,000 kg. more than the present weight limit to be permitted to land at Caticlan airport.

As a stop-gap measure, the Civil Aviation Authority of the Philippines has ordered the filling up and leveling at the runway 24's end, which should add 90 meters and lengthen the runway safe area to 1,040 meters thereby allowing the ATR, as the biggest critical equipment, more landing roll just in case.

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