Lost communications
What 14 CFR 91.185 requires you to fly, and when, if your radio goes silent under IFR.
16 min read · IFR emergencies
After this lesson you can
- Try the right things, in order, before concluding the radio is actually dead.
- Apply the AVEF order (Assigned, Vector, Expected, Filed) to choose a route.
- Apply the highest-altitude rule to a route where the MEA changes underneath you.
- Decide when to leave a clearance limit and start an approach, with or without an expect-further-clearance time.
Losing two-way radio contact while inside a cloud is one of the scenarios beginning instrument pilots dread most, but it is also one of the best-covered situations in the regulations. 14 CFR 91.185 gives you an exact, memorizable playbook for the route to fly, the altitude to fly it at, and the moment to start your approach, all without a single word from ATC.
The good news is that a full transmit-and-receive failure is rare. Most "lost comm" events are a stuck frequency, a bad connection, or a failure in one direction only. So the first job is not regulation, it is troubleshooting: give yourself a real chance to get your voice back before you fly the rest of this lesson from memory.
The rest of this lesson
- 1.Troubleshoot before you assume the worst
- 2.If you can still see outside, that changes everything
- 3.Choosing your route: AVEF
- 4.Choosing your altitude: the highest of three
- 5.A worked flight, start to finish
- 6.If the clearance limit is not an approach fix
- 7.Getting found: squawk, light guns, and staying predictable
These 7 sections, their figures, the checks along the way and the end-of-lesson quiz come with the IFR track. Paid once, yours for good.
Key terms
Try to recall each definition before turning the card.