The Civil Aviation Authority of Vietnam (CAAV) listed various factors leading to the extensive delay the country experienced in June including inefficient air traffic management procedures. A southern air traffic control representative added that “pilot skills” are among the factors for the delay, let’s see what local pilots have to say on this accusation.
According to the CAAV, 18% of the total number of 5,600 flights operated by local airlines were delayed in June. LCC Vietjet Air is ‘leading’ the delay board with 24%of their flights delayed followed by the national carrier Vietnam Airlines at 20%.
Duty Head of CAAV Ho Minh Tan, described the delay in Tan Son Nhat Airport to be “quite serious” and suggests the airport has the highest number of delayed flights among all Vietnamese airports. He further suggests the airport infrastructures are overloaded and the assignments of aircraft parking are “unreasonable”, with departing aircraft parked farther away from the runway.
However, Bui Thanh Ha, Head of the Air Traffic Control Department of Southern Region Air Traffic Services added another reason. He suggests the longer runway occupancy time required by Vietnamese pilots is a significant factor in the delay.”It is clear that our pilots do not have an awareness of saving time,” says Ha, followed by quoting an example of how a survey conducted in the airport suggests a Singapore Airlines aircraft left the runway after landing in 60 seconds while Vietnamese pilots require nearly 70 seconds. Ha also suggests that Vietnamese pilots spend an average of 10-15 seconds to start rolling on the runway after being cleared for takeoff.
How accurate is the accusation?
Two Runways One System at Tan Son Nhat International Airport
Tan Son Nhat Airport has two runways, with runway 25L used for taking off and runway 25R used for landing more than 90% of the time. However, due to the physical limitations of the distance between the runways, the two runways are operated dependently as a single runway system. This means an aircraft is not allowed to take off unless the landing aircraft has touched down on the parallel runway. This procedure is to ensure safe separation in case the landing traffic executes a go-around which would result in two aircraft climbing in the same direction at close proximity.
Unlike TSN airport, modern major airports like Suvarnabhumi International Airport in Thailand are designed with a terminal between the runways, ensuring a minimum of 760m (specified by ICAO) between runway centerlines where the runways can be operated as two independent systems.
Unfortunately, TSN airport which was first established as a military airfield in the middle of Ho Chi Minh City is now surrounded by civilian buildings, and could not be upgraded due to the physical constraint of the city’s development.
“Our pilots do not have awareness of saving time”
With the two runways in one system in effect, the chances are that departing aircraft are readily lining up for take-off during peak hours. A quick observation on flightradar24 gives us a somewhat different insight to what Ha suggests. After the preceding traffic takes off, the next aircraft lines up immediately in less than 20 seconds.
“Singapore Airline’s aircraft left the runway after landing in 60 seconds”
Singapore Airlines operates the Boeing 787 and the Airbus 350 for their service connecting Changi Airport and Tan Son Nhat Airport. Both of which are the most advanced models in respect to their manufacturers with advanced technology like the Brake-To-Vacate(BTV) extension of the Airbus auto flight system. It was not clearly stated which model the “Vietnamese pilots” was compared to in the survey. Whilst Vietnam Airlines has both the B787 and the A350, other models such as the A320, Embrarer190, and the ATR72 are still widely used by other local airlines. It is unfair to compare the landing occupancy time of one flight to an unidentified Vietnamese carrier. The invalidity of this comparison extends to the operational differences subjected to local weather conditions. A wet runway, a strong tailwind, and different landing weights are just some of the factors that affect the landing distance. How could Ha have concluded that the pilot skills of the local pilots are the reason for the extra 10 seconds of occupancy time, hence the delay? Furthermore, the departing aircraft can immediately takeoff after the landing aircraft has touched down(not after vacating), so how does runway occupancy time result in more delay in this situation?
“Vietnamese Pilots still take 10-15 seconds to start running”
Assuming “Vietnamese pilots” means “Vietnamese airline pilots” as it could be a mistake lost in translation, ICAO requires an aircraft to start moving 60 seconds after being clear for takeoff unless specified otherwise. A mere 10-15 seconds lapse in moving is quite acceptable as even when the engines are set to takeoff power, the aircraft’s momentum will take a few seconds to be countered by the thrust.
Whether “pilot skills” are considered a factor, the extensive delay experienced in Vietnam airports would likely continue to disrupt travelers for the rest of the summer holiday. New procedures have been implemented to alleviate the disruption but it is not likely that the situation will improve until the new airport in Ho Chi Minh City is completed.
Would Tan Son Nhat have to cut flights like Heathrow to meet realistic supplies? Do you think pilot skills are a significant factor in the extensive delays experienced worldwide now? Let us know below.
