Capability
Surveillance & Transponders
Transponder and altitude-reporting equipment repaired, bench-tested and verified with documented results.
Overview
What we see, and what we do.
Surveillance findings usually arrive as a report from someone else — a controller query, a discrepancy noticed on the ground, a failed check. That makes them awkward to chase, because the aircraft is rarely in front of you when the fault is observed.
The bench is where this gets resolved properly. Transponder power, frequency and reply behaviour are all measurable, and a documented test either clears the unit or identifies it, which stops the fault bouncing between the transponder, the encoder and the antenna.
Equipment We Service
- Mode A/C Transponder
- Mode S Transponder
- Transponder Antenna
- Traffic Advisory System Processor
- Traffic Computer
- Altitude Reporting Encoder
- Control Head
Faults We See Most
- No reply or intermittent reply reported by ATC
- Altitude reporting discrepancy
- Low transmit power on bench test
- Failed transponder certification check
- Traffic system false or missing targets
- Control head selection not commanding the unit
Recognise one of these? Describe what was observed rather than what you think has failed — it is frequently a different unit.
Common Questions
Surveillance & Transponders,
asked in practice.
- We failed a transponder check. What happens next?
- The useful question is which part failed. Transmit power, reply behaviour and altitude reporting are separately measurable, so a bench test either identifies the transponder or clears it and moves the investigation to the encoder, the antenna or the wiring.
- Can the transponder be serviceable and the altitude still wrong?
- Yes, and it frequently is. Altitude reporting originates upstream in the encoder or air data source. A transponder faithfully transmitting incorrect data is working exactly as designed.
Next Step
Surveillance & Transponders on the bench?
Send us the part number.
Tell us the aircraft, the symptom and the number on the dataplate. We will confirm whether we service it and what the options are.