Ratmalana: An international airport without modern navigational and landing aids

In 1934 the State Council of Ceylon decided that an airport with easy access to Colombo was a necessity and declared that Ratmalana was the best site available. Accordingly, an airfield was built, and the first landing took place on 27 November 1935 at what became Ceylon’s first dedicated aircraft landing ground. During World War II the airport expanded, and a ‘hard’ runway was built.

- CAPT GA FERNANDO

To assist aircraft landing in bad weather and resulting bad visibility, a transmitter was built at Talangama to generate a radio signal beam, called a ‘radio range’, directed along the extended centreline of the Ratmalana runway. If the aircraft was tracking along the correct path, pilots would hear a continuous tone in their headsets. However, if they were left of the desired track, they would hear the letter ‘A’ transmitted in Morse Code (‘dit-dah’); or if right of the beam, the Morse letter ‘N’ (‘dah-dit’). The objective was to hear a continuous signal guiding them toward Ratmalana along the extended centreline of the runway.

Later, a low-frequency Non-Directional Radio Beacon (NDB) transmitter was installed at Attidiya in the vicinity of the airport, and used in conjunction with an Automatic Direction Finder (ADF) onboard the aircraft. A needle on a compass dial in the aircraft pointed to Attidiya, giving directional guidance. Although this system was useful, when most needed, for example during thunderstorm activity, there was static interference and the needles pointed toward the storm instead of at Attidiya. So, a Very High Frequency Omni Directional Radio Range (VOR) was installed for more accuracy and reliability.

After WW2 Ratmalana Airport was served by a few international airlines such as Air Ceylon, Indian Airlines, BOAC (British Overseas Airways Corporation) and TWA (Trans World Airlines). But in 1968 the airport lost its ‘international’ status when Bandaranaike International Airport opened and all international operations moved to Katunayake. Subsequently, the equipment at Ratmalana was allowed to deteriorate; radio navigational let-down aids were no longer operative, and there was no proper control tower. The civil training aircraft of the government’s flying school had neither radios nor radio aids to navigation.