NCAA Aeronautical Station Operator case studies
NCAA Aeronautical Station Operator · Put your knowledge to work in context.
The Aeronautical Station Operator credential, examined under the Nigerian Civil Aviation Authority (NCAA), certifies that a person can operate an aeronautical station: the ground end of air-ground radiotelephony and the aeronautical fixed telecommunication network. It is aimed at staff of aeronautical stations, communication centres and AFTN message-switching offices, and at aviation personnel whose duties include accepting, relaying and logging aeronautical traffic. The NCAA Aeronautical Station Operator case studies are 5 cases and about 4,234 words.
1Kalda Regional: an expired licence, a hilltop repeater and an unqualified handheld
Kalda Regional Aerodrome (KDRX) operates an aerodrome flight information service under a national aeronautical station licence that names the station location, two assigned VHF frequencies (118.300 for AFIS, 121.700 for apron), a transmitter power of 25 W, and an antenna height of 18 m AGL. The licence expired 90 days ago: the renewal form was submitted but the fee was never paid and the application was returned.
824 words, about 4 min2Sunridge FIS: feedline loss, a power upgrade and a summer duct
Sunridge Flight Information Service covers a valley aerodrome from a hilltop site at 640 m AMSL. The VHF installation is a 25 W transmitter on 118.550, 60 m of RG-213 feeder (manufacturer data: 3.5 dB loss per 30 m at 130 MHz), 1.0 dB total loss for connectors and the lightning arrestor, and a single collinear with 6 dBd gain mounted 20 m above the equipment hut.
807 words, about 4 min3AFTN circuit failure with a runway-closure NOTAM waiting
At 0215 UTC the AFTN circuit linking the KDRX communication centre to the regional COM centre fails; the terminal shows no line sync and repeated retries fail. A backup dial-up link exists but must be established manually by the on-call technician, who will not arrive for 45 minutes.
887 words, about 4 min4MAYDAY on the AFIS frequency while an ELT sweeps 121.5
At 1432 UTC the KDRX aerodrome flight information service, staffed by a single watchkeeper, is working three aircraft on 118.300 when a continuous swept-tone signal appears on the 121.5 receiver, characteristic of an ELT. Twenty seconds later an aircraft on 118.300 transmits 'MAYDAY MAYDAY MAYDAY, KDRX, engine failure, twelve miles north of the field, descending, one person on board'.
848 words, about 4 min5Paging transmitter interference, a 40-minute log gap and a handheld guard receiver
KDRX shares a hilltop radio site with a commercial paging operator whose 100 W transmitter on 152.6 MHz was commissioned six months ago. Since then the AFIS receiver on 118.300 emits a loud buzz and loses weak aircraft transmissions whenever the paging transmitter keys; the buzz stops when the paging antenna is disconnected during a test.
868 words, about 4 min