Rising to the Challenge for Better
Forecasting Service
Hong Kong Observatory, Government Flying Service

Exemplary Services@Gov
2013

Avoiding significant weather is the norm in aviation. In this partnership project, however, pilots from the Government Flying Service (GFS) need to fly near tropical cyclones over the South China Sea. Their mission is to collect meteorological data for the Hong Kong Observatory (HKO) to make more timely and accurate weather forecasts for tropical cyclones in order to reduce the loss due to the storms.

Flying into storms to gather meteorological data

As there are limited numbers of meteorological observation stations over the northern part of the South China Sea, it has always been challenging for the HKO to analyse and forecast the tropical cyclones. In the past, storm position and intensity were deduced indirectly from tracking the movement and development of cloud clusters and thunderstorms on satellite and radar images. Since 2011, the GFS and the HKO have worked in tandem to improve this situation. When additional data of tropical cyclones over the South China Sea are required, GFS pilots will fly a fixed-wing aircraft equipped with meteorological measuring instrument to the proximity of tropical cyclone centre. Raw data including temperature, humidity, air pressure, wind direction and wind speed are collected directly using the instrument. The HKO will then combine the aircraft observations with other meteorological data and computer weather model to calculate the storm position and intensity. Improvements on forecasting of tropical cyclone movement and precipitation can be made such that the public and related organisations can take precautionary measures in a timely way for the inclement weather and protect the safety of life and property.

Shared goal and comprehensive planning

The team encountered several problems in data transmissions during the project trial. With determination and professionalism, the team had implemented improvement measures on testing and backup of data in order to optimise the data transmission and processing workflow. The data problems were resolved eventually to facilitate smooth provision of flight observations to the forecasting office.

Apart from the search and rescue operations, GFS pilots found it meaningful and are proud to serve the public in this new way. On top of the task requirements, they also took photographs of the weather and sea conditions inside the tropical cyclones, providing information to colleagues in the HKO for a more in-depth understanding of meteorological conditions inside the tropical cyclones.

Sending an aircraft to collect meteorological data of tropical cyclones is an extremely difficult mission. Therefore, only a few meteorological organisations in the world have such techniques and resources to carry out the operation. In 2011 and 2012, the team conducted data collection flights for six tropical cyclones, including Vicente, Kai-tak and Tembin. These successful operations have written a new chapter in the history of Hong Kong's meteorological surveillance flight.

The advanced meteorological measuring system installed on GFS fixed-wing aircraft collects themeteorological data and flight locations at a high frequency of 20 times per second.
The advanced meteorological measuring system installed on GFS fixed-wing aircraft collects themeteorological data and flight locations at a high frequency of 20 times per second.
To ensure crew safety, team members from the two departments communicate closely in planning of flight paths based on the latest weather conditions.
To ensure crew safety, team members from the two departments communicate closely in planning of flight paths based on the latest weather conditions.
Photograph taken by GFS pilot of the weather condition during a reconnaissance flight to the centre of tropical cyclone Kai-tak.
Photograph taken by GFS pilot of the weather condition during a reconnaissance flight to the centre of tropical cyclone Kai-tak.