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Lost Communication

Introduction:

  • You've been flying along enjoying your day sight seeing as you approach the controlled airspace above your destination only to realize you cannot reach the control tower
    • You're low on gas, you cannot talk to anyone, what will you do?
  • Good judgment must always be exercised as it is virtually impossible to provide regulations and procedures for all situations
    • Intercept a "known value," on in other words, be as predictable to ATC and other aircraft as you can

Lost Communications:

  • If the cause of the lost communication is not obvious, there is a fair chance it is user error
    • Ensure the correct frequency has been set and the volume turned up
    • Check to ensure your mic is not stuck
    • Troubleshoot all connections (cords)
    • If available, try an alternate frequency (FSS/ARINC)
      • There is almost always a VHF frequency given for every UHF, one of them may not be monitored while the other is
      • There is no order or precedence for trying to contact ATC, including using guard, use all at once if necessary
      • If communications are established with an FSS or ARINC, the pilot should advise that radio communications on the previously assigned frequency has been lost giving the aircraft's position, altitude, last assigned frequency and then request further clearance from the controlling facility. The preceding does not preclude the use of 121.5 MHz. There is no priority on which action should be attempted first. If the capability exists, do all at the same time
      • *Aeronautical Radio/Incorporated (ARINC) is a commercial communications corporation which designs, constructs, operates, leases or otherwise engages in radio activities serving the aviation community. ARINC has the capability of relaying information to/from ATC facilities throughout the country
    • Roll back to the last frequency you were on, if available to test
    • Attempt another frequency, attempt guard
    • Utilize VOR frequencies if able
  • If you are not able to re-establish communication with ATC, set your transponder, if equipped, to squawk 7600 for lost comm
  • Continue to make radio calls in the blind:
    • Pilot: "In the blind, [Message], in the blind"
  • If able to maintain flight in VMC continue under VFR and land as soon as practicable and notify ATC
  • It is possible to go "NORDO" while you still have communications because you can't hear them
  • If communications are established, advise frequency communications was lost on and request further clearance from the facility
  • Transponder Operation During Two-way Communications Failure:

    • If an aircraft with a coded radar beacon transponder experiences a loss of two-way radio capability, the pilot should adjust the transponder to reply on Mode A/3, Code 7600
    • The pilot should understand that the aircraft may not be in an area of radar coverage

Lost Communications in Visual Conditions:

  • If the failure occurs in VFR conditions, or if VFR conditions are encountered after the failure, each pilot must continue the flight under VFR and land as soon as practicable
    • Note: This procedure also applies when two-way radio failure occurs while operating in Class A airspace. The primary objective of this provision in 14 CFR Section 91.185 is to preclude extended IFR operation by these aircraft within the ATC system. Pilots should recognize that operation under these conditions may unnecessarily as well as adversely affect other users of the airspace, since ATC may be required to reroute or delay other users in order to protect the failure aircraft. However, it is not intended that the requirement to “land as soon as practicable” be construed to mean “as soon as possible.” Pilots retain the prerogative of exercising their best judgment and are not required to land at an unauthorized airport, at an airport unsuitable for the type of aircraft flown, or to land only minutes short of their intended destination
  • The ultimate goal of lost comm IFR scenario is to reach the destination, breaking out ASAP and landing VFR
  • Without radios, weather updates, and altimeter settings which are paramount to instrument flying are unobtainable
  • Try to make contact with the tower and a clearance (light gun) to land by circling the field

Lost Communications in Instrument Conditions:

  • If the failure occurs in IFR conditions, or if lost communications in VFR conditions (above) cannot be complied with, each pilot must continue the flight according to the following
  • Unless otherwise authorized by ATC, pilots must comply with, and service will be provided, on the basis that the pilot is operating in accordance with FAR 91.185
  • Fly the AVEnue of FAME
  • Route:

    • A: Route assigned in last ATC clearance received;
    • V: If being vectored, by the direct route from the point of radio failure to the fix, route, or airway specified in the vector clearance;
    • E: By the route that ATC has advised you may be expected in an EFC;
    • F: By the route filed on the flight plan
  • Fly the HIGHEST of the following altitudes for the FOR THE ROUTE SEGMENT BEING FLOWN:

    • M: Minimum altitude for IFR operations (MEA) (as prescribed in 19.121(c))
    • E: The altitude ATC has advised you may expect in an EFC
    • A: Last assigned
  • Do not descend below MSA until established on the approach
  • Note: The intent of the rule is that a pilot who has experience two-way radio failure should select the appropriate altitude for the particular route segment being flown and make the necessary altitude adjustments for subsequent route segments. If the pilot received an "expect further clearance" containing a higher altitude to expect at a specified time or fix, maintain the highest of the following altitudes until that time/fix:
    1. The last assigned altitude; or
    2. The minimum altitude/flight level for IFR operations
  • Upon reaching the time/fix specified, the pilot should commence climbing to the altitude advised to expect. If the radio failure occurs after the time/fix specified, the altitude to be expected is not applicable and the pilot should maintain an altitude consistent with 1 or 2 above. If the pilot receives an "expect further clearance" containing a lower altitude, the pilot should maintain the highest of 1 or 2 above until that time/fix specified to leave the clearance limit
  • If you are below your ESA (25-100 miles) or the MSA (0-25 miles) and not established on a part of the approach than make a climb above that altitude until established

Example:
A pilot experiencing two-way radio failure at an assigned altitude of 7,000 feet is cleared along a direct route which will require a climb to a minimum IFR altitude of 9,000 feet, should climb to reach 9,000 feet at the time or place where it becomes necessary (see 14 CFR Section 91.177(b)). Later while proceeding along an airway with an MEA of 5,000 feet, the pilot would descend to 7,000 feet (the last assigned altitude), because that altitude is higher than the MEA

Example:
A pilot experiencing two-way radio failure while being progressively descended to lower altitudes to begin an approach is assigned 2,700 feet until crossing the VOR and then cleared for the approach. The MOCA along the airway is 2,700 feet and MEA is 4,000 feet. The aircraft is within 22 NM of the VOR. The pilot should remain at 2,700 feet until crossing the VOR because that altitude is the minimum IFR altitude for the route segment being flown

Example:
The MEA between a and b: 5,000 feet. The MEA between b and c: 5,000 feet. The MEA between c and d: 11,000 feet. The MEA between d and e: 7,000 feet. A pilot had been cleared via a, b, c, d, to e. While flying between a and b the assigned altitude was 6,000 feet and the pilot was told to expect a clearance to 8,000 feet at b. Prior to receiving the higher altitude assignment, the pilot experienced two-way failure. The pilot would maintain 6,000 to b, then climb to 8,000 feet (the altitude advised to expect). The pilot would maintain 8,000 feet, then climb to 11,000 at c, or prior to c if necessary to comply with an MCA at c. (14 CFR Section 91.177(b).) Upon reaching d, the pilot would descend to 8,000 feet (even though the MEA was 7,000 feet), as 8,000 was the highest of the altitude situations stated in the rule (14 CFR Section 91.185)

NOTE:
If you are given an altitude to expect and you climb to that altitude and then get a radio failure it is no longer expected and does not apply, refer to the MEA or last assigned altitude

NOTE:
If the pilot receives an EFC containing a lower altitude, the pilot should maintain the highest of 1 or 2 above until the time/fix specified

Leaving a clearance limit:

  • When the clearance limit is a fix from which an approach begins (IAF):

    commence descent or descent and approach as close as possible to the expect further clearance time if one has been received, or if one has not been received, as close as possible to the Estimated Time of Arrival (ETA) as calculated from the filed or amended (with ATC) Estimated Time En Route (ETE)
  • If the clearance limit is not a fix from which an approach begins:

    leave the clearance limit at the expect further clearance time if one has been received, or if none has been received, upon arrival over the clearance limit, and proceed to a fix from which an approach begins and commence descent or descent and approach as close as possible to the estimated time of arrival as calculated from the filed or amended (with ATC) estimated time en route

Landing Pattern:

  • Look for a green light from tower signifying you are cleared to land on any runway
  • Take the first attempt to land around fuel permitting if no lights received by tower
  • On your second trip around, clear the runway yourself if no lights and land

Radar Approaches:

  • Initiate lost communication procedures if no transmissions are received for approximately 1 minute while being vectored to final, 15 seconds while on ASR final approach or 5 seconds while on PAR final approach
  • If unable to reestablish comm and unable to maintain VMC proceed with a published IAP or previously coordinated instructions
  • Maintain the last assigned altitude or the MSA (ESA if beyond 25 NM) whichever is higher, until established on a segment of an IAP
  • You need to be aware of your location for executing the missed approach instructions, you can climb to whatever altitude assigned but you cannot turn until you are at the MAP as best you can determine it

Communications with Tower when Aircraft Transmitter or Receiver or Both are Inoperative:

  • Arriving Aircraft:
    • Receiver inoperative

      • Remain outside or above class D until the direction and flow has been determined then advise the tower of intentions:
        • "[Location] Tower, [Aircraft Type], [Position], [Altitude], [Intention to Land], request control with light signals"
      • When you are approximately 3 to 5 miles from the airport advise tower of your position and join the pattern while looking for/following light gun signals
      • Thereafter, transmit your position to tower as normal
    • Transmitter inoperative:

      • Remain outside class D surface area until direction and flow has been determined then join the pattern
      • Monitor the primary frequency (See Sectional Charts) and look for light gun signals
      • Acknowledge signals in the day with a wing rock and at night by flashing your lights in irregular patterns
      • During daylight hours, hovering helicopters will turn in the direction of the controlling facility and flash the landing light
        • While in flight, helicopters should show their acknowledgment of receiving a transmission by making shallow banks in opposite directions
      • At night, helicopters will acknowledge receipt of transmissions by flashing either the landing or the search light
      • Always transmit in the blind
    • Transmitter and Receiver Inoperative:

      • Remain outside or above the Class D surface area until the direction and flow of traffic has been determined; then, join the airport traffic pattern and maintain visual contact with the tower to receive light signals
      • Acknowledge light signals as noted above

  • Departing:

    • If you experience radio failure prior to leaving the parking area, make every effort to have the equipment repaired
    • If unable, you may contact tower via phone and request authorization to coordinate takeoff without two-way radio communications
    • If tower authorization is granted, you will be given departure information and requested to monitor the tower frequency or watch for light signals as appropriate
    • During daylight hours, acknowledge transmissions or light signals by moving the ailerons or rudder
    • At night, acknowledge by blinking the landing or navigation lights
    • If departing and you go lost comm, be predictable, look for light gun signals and return to parking

Night:

  • If night VMC, proceed into the airport, looking for the ALDIS lamp signal for clearance to land

Formation:

  • In the event of lost communications between aircraft, a join-up should be affected at a pre-briefed NORDO rendezvous point
  • Left turns indicate NORDO only
  • Right turns indicate additional problems with the aircraft
  • Following join up, standard HEFOE signals will be utilized to relay additional aircraft problems to the other aircraft
  • If all attempts at rendezvous fail, single aircraft recoveries shall comply with FAA procedures and local course rules
  • The NORDO aircraft flies wing
  • Lead will coordinate a 1/2 flap straight-in approach
  • If the NORDO aircraft requires an arrested landing, he shall lower his hook
  • The good aircraft shall coordinate an arrested landing for the NORDO wingman, and put the hook down once clearance has been received
  • Day VMC:
    • In section:
      • The NORDO aircraft should fly wing on the lead aircraft during return to base
      • Lead should request a straight-in approach
      • The approach shall be flown at half flaps and 150kts but no slower than on-speed for the heavier aircraft
      • The lead shall "pat the dash" and detach the NORDO aircraft at 3/4 mile (with a centered ball when available) if cleared to land
      • With dual runways available, the NORDO aircraft shall be crossed to the side corresponding to the runway he is cleared to land on
      • After detaching the NORDO aircraft, the good aircraft shall take a cut away and continue the approach abeam the NORDO aircraft so as to be available for join-up in the event the NORDO aircraft doesn't land or is waved off
        • Lower full flaps
      • In that case, the NORDO aircraft shall rejoin the lead for another approach
  • Night/IMC:
    • Single aircraft:
      • In formation he HEFOE code may be used to visually indicate malfunctioning equipment
      • Hold your flashlight at the top of the canopy pointed towards your wingman for about 5 seconds
      • Flash the flashlight using a 1 second on and 1 second off cadence the appropriate number of times
    • In section:
      • The NORDO aircraft shall fly the wing position with all lights on
      • The lead aircraft shall have all lights on except his strobe lights
      • Configuration change signals to the wingman should be initiated through the external master light switch IAW NATOPS (2 flashes=gear, 3 flashes=speed-brake) and a smart break away
      • Lead shall initiate detachment at 3/4 NM by turning on the strobe light and then initiating a positive turn away

Communication Breakdowns:

  • Similar callsigns: use full aircraft identification (do not abbreviate) and listen closely to frequency; if there is ANY doubt or confusion, ask!
  • Don't hear what you expect, listen
  • During periods of high ATC workload, ATC may not catch a readback error so the pilot must be extra vigilant listening and looking for traffic
  • Think before you speak, and write down anything to avoid confusion
  • Use proper phraseology

Reestablishing Radio Contact:

  • In addition to monitoring the NAVAID voice feature, the pilot should attempt to reestablish communications by attempting contact:
    • On the previously assigned frequency; or
    • With an FSS or *ARINC
      • *Aeronautical Radio/Incorporated (ARINC) is a commercial communications corporation which designs, constructs, operates, leases or otherwise engages in radio activities serving the aviation community. ARINC has the capability of relaying information to/from ATC facilities throughout the country
  • If communications are established with an FSS or ARINC, the pilot should advise that radio communications on the previously assigned frequency has been lost giving the aircraft’s position, altitude, last assigned frequency and then request further clearance from the controlling facility
    • The preceding does not preclude the use of 121.5 MHz. There is no priority on which action should be attempted first. If the capability exists, do all at the same time

Conclusion:

  • It is virtually impossible to provide regulations and procedures applicable to all possible situations associated with two-way radio communications failure which leaves pilots confronted by a situation not covered in the regulation, to exercise good judgment in whatever action they elect to take
  • In the event of two-way radio communications failure, ATC service will be provided on the basis that the pilot is operating in accordance with 14 CFR Section 91.185
    • A pilot experiencing two-way communications failure should (unless emergency authority is exercised) comply with 14 CFR Section 91.185
  • Should the situation so dictate they should not be reluctant to use the emergency action contained in 14 CFR Section 91.3(b)
    • Whether a two-way communications failure constitutes an emergency depends on the circumstances, and in any event, it is a determination made by the pilot-in-command
  • Chair fly! Always ask yourself what if so you can react correctly should the situation every present itself

References: