Radio failure, unlawful interference and distress calls

Free lesson · Air Regulations · DGCA CPL and ATPL

Three bad days, step by step: the radio dies in cloud, the aircraft is under unlawful interference, and you hear someone else's distress call.

What do you do when the radio dies in IMC?

Radio failure

In VMC: stay VMC, land at the nearest suitable aerodrome. In IMC, fly these steps.

  1. Hold level and speed 20 min, 7 under radar Hold the last speed and level you were given (or the minimum flight altitude, if that is higher). Without radar, do this for 20 minutes after missing a compulsory report. Under radar, for 7 minutes from the latest of: reaching the level, squawking 7600, or missing a report.
  2. Rejoin the route if you were being vectored Get back on your flight plan route by the next significant point at the latest.
  3. Fly to destination aid hold until approach time Fly to the designated navaid or fix serving the destination and hold there if needed.
  4. Start descent at expected approach time Use the last received and acknowledged EAT. With none, use the ETA from the flight plan.
  5. Normal instrument approach at the destination aid Fly a normal instrument approach procedure at the destination aid.
  6. Land within 30 min of ETA Within 30 minutes after the ETA or the last acknowledged EAT, whichever is later.

Memory hook: Radar 7, no radar 20: the more ATC can see, the shorter you wait.

Takeaway: Squawk 7600, hold level and speed 20 minutes (7 under radar), fly to the destination aid, descend at approach time, land within 30 minutes.

Unlawful interference in flight: what does the crew do?

Unlawful interference

When you must leave your track or level without talking to ATS.

  1. Keep track and level until you can notify If you can't reach an aerodrome by the rules, continue on the assigned track and level at least until you can notify ATS or are in radar or ADS-B coverage.
  2. Squawk 7500, or 7700 Use transponders and data links too, when they help (Chapter 12 lists the codes).
  3. Broadcast warnings VHF in use and emergency Broadcast on the VHF channel in use, the VHF emergency frequency and other channels, unless conditions on board prevent it.
  4. Doc 7030 contingency if published Follow the region's special in-flight contingency procedures, which are published in Doc 7030 (Regional Supplementary Procedures).
  5. Otherwise offset level 500 ft or 1000 ft Fly a level offset from normal IFR levels by 150 m (500 ft) where 1000 ft separation applies, or 300 m (1000 ft) where 2000 ft applies.

Memory hook: Half the separation: 500 for 1000, 1000 for 2000.

Takeaway: Keep track and level until ATS knows. Forced off: broadcast, follow Doc 7030, else offset 500 ft (1000 ft in 2000 ft airspace).

What do you do if you hear a distress call?

Distress heard

Four actions, in order. Press Fly it.

  1. Acknowledge IF FEASIBLE Acknowledge the distress transmission when you can.
  2. Log POSITION AND BEARING Note where the craft in trouble is and, if you can, take a bearing on it.
  3. Inform RCC OR ATS, WITHOUT DELAY Pass everything you have to the rescue coordination centre or ATS unit.
  4. Proceed AT PILOT'S DISCRETION While awaiting instructions, you may head toward the position given.

Memory hook: A-L-I-P: Acknowledge, Log, Inform, Proceed.

Takeaway: Acknowledge if you can, log the position and a bearing, tell the RCC or ATS, then you may head there.