Lost Comms in Controlled Airspace
You are on an IFR flight in controlled airspace at 8,000 ft, cleared to a destination 60 nm ahead. Your radio fails completely: no transmit, no receive. You are in IMC, have a serviceable transponder with Mode C, and your last clearance was 'descend to 6,000 ft, cleared to the destination, expect the ILS runway 27.' The aircraft has a filed flight plan and a published standard lost-communication procedure for the destination. There is an Air Traffic Control unit frequency published for lost communications, and you have a handheld radio in the flight bag.
1. What are your immediate actions after the radio failure?
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Squawk 7600, maintain the last assigned level and route, and continue to the destination in accordance with the last clearance and the published lost-communication procedure. Attempt to restore communications: check headsets, plugs, volume, squelch, and try the handheld radio on the published lost-comms frequency. Listen on the destination's navigation frequencies for instructions. Do not change altitude or route without following the published procedure; the clearance to descend to 6,000 ft and proceed to destination governs.
2. How does the published lost-communication procedure shape your arrival?
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Follow the procedure exactly: it typically specifies the route, altitudes, and timing for the approach, often requiring you to arrive at a specified fix at an expected time, then fly the approach and land. Because you are in IMC, you cannot rely on visual separation, so the procedure is your separation assurance. If the procedure requires holding, hold at the specified fix and altitude. Set your transponder to 7600 throughout and monitor the published frequency. If the handheld works, announce your position and intentions on the lost-comms frequency.
3. What should you do if you cannot establish communication and the procedure is ambiguous?
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Choose the safest conservative option: continue to the destination, fly the published approach, and land if conditions permit, while squawking 7600. If weather at destination is below minima, divert to a suitable alternate using the lost-comms procedure for that aerodrome if one exists. Keep the transponder on and consider 7700 only if you are in distress, not merely because communications failed. After landing, contact ATC by telephone as soon as possible to close the flight plan and explain.