Loss of Communication Required IFR Communications–MATHCALLS. Missed Approach Altitude changes when VFR on top True Airspeed changes of 5% or 10kts, whichever is less Holding altitude and time when entering or leaving fix
21 Cannot maintain 500fpm climb Altitude and time when arriving at clearance limit Leaving assigned altitude Loss of required navigation equipment Safety of flight including unforcasted weather When not in radar contact, these calls must be made as well: All required IFR calls when in radar contact Inbound on outer marker or final approach fix ETA changes of greater than 3 minutes Loss of Communications–Route (AVEF): Proceed to most recently Assigned route, Vectored route, Expected route, or Filed route (in that order). Altitude (MEA): Highest out of your MEA, Expected, or Assigned. Approach: If your clearance limit is an IAF, fly to the approach fix, hold until EFC or ETA, then shoot the approach. If clearance limit is not an IAF, fly to clearance limit, hold until EFC, and shoot the approach. If no EFC time, fly to clearance limit, then fly to an IAF, hold until ETA, then shoot approach. That is the way to do approaches in lost coms according to the regs. That said, it’s probably not what you’re going to do in reality should the situation occur. As soon as you lose coms, you should squawk 7600. ATC now knows you do not have coms, and will clear traffic out of the way for you. What I would do is get to a published hold on an approach, hold until my ETA, then shoot the approach. Light Gun–91.125. I don’t feel like writing them out.Engine Failure in IMC–This is very situational, but the general consensus is to shoot for water. Pitch for best glide, run your checklists, declare emergency, 7700, and if you have no visibility the entire way down, use the GPS to find the closest body of water. Unhinge your doors and brace. There’s a good chance the aircraft will flip once you strike the water, so be ready to abandon ship. If there’s no water nearby, most modern GPSs show major highways, so you could try lining up with one. ETE/ETA–Estimated Time Enroute can be calculated using formula (60 ÷ Groundspeed) × Distance. E6B can also be used to calculate ETE. ETE + Current time = ETA.