11.3 Lost Link, Flyaway & Emergency Procedures
Key Takeaways
- Configure and brief lost-link behaviour before flight: return-to-home (RTH), hover/loiter, or land/descent—each is appropriate only for specific site geometries near people or controlled airspace.
- A flyaway is loss of effective control with the aircraft departing the intended operation; recognize it early, attempt recovery, protect people, and notify the right authorities.
- Contact ATC when the occurrence affects or may enter controlled airspace/aerodrome environments; use emergency services for ground risk; notify Transport Canada as required for the occurrence type.
- Select emergency landing zones in the site survey; maintain continuous see-and-avoid; crewed aircraft always have right of way over RPAS.
- CAR 901.16 flight-safety themes, formation limits under 901.36, and multiple-RPA limits under 901.40 constrain how you operate and recover in shared airspace.
11.3 Lost Link, Flyaway & Emergency Procedures
Quick Answer: Before launch, set a lost-link mode that fits the site—RTH, hover/loiter, or land—and brief the crew. On flyaway, try recovery, keep people clear, and notify the right parties (ATC if controlled airspace/aerodrome risk, emergency services for ground hazard, Transport Canada as required). Always see-and-avoid, give right of way to crewed aircraft, use planned ELZs, and respect 901.16, formation 901.36, and multiple-RPA 901.40 limits.
Lost-link and flyaway handling is a Standard 921.02 / TP 15395 flight-review theme and a high-yield Advanced written topic. The exam rewards pilots who pre-program predictable behaviour and who know who to call—not pilots who only memorize marketing names for smart features.
Lost link defined
A lost link (loss of command-and-control) means the pilot can no longer reliably command the aircraft through the control link. Causes include RF interference, excessive range, terrain/building masking, GCS power failure, aircraft radio failure, or spectrum congestion.
Lost link is not automatically a flyaway. Many systems enter a pre-selected contingency mode. Your job is to ensure that mode is safe for this site.
Programmed lost-link behaviours
| Mode | Typical behaviour | Best when | Risky when |
|---|---|---|---|
| Return-to-home (RTH) | Climbs to set altitude (if configured), navigates to home point, lands or hovers per settings | Home point is clear, RTH altitude clears obstacles, path does not cross crowds or approach paths | Home is across a highway of people; RTH altitude tunnels through wires; home was never updated after moving the launch point |
| Hover / loiter | Holds position (and altitude) waiting for link restoration | Short expected outages; position is already clear of people and traffic; VO can still see aircraft | Holding over people, over a road, or in controlled airspace without a recovery plan; wind drifts the hover |
| Land / controlled descent | Descends and lands at current location or along a simple profile | Directly over a prepared clear ELZ; low altitude; RTH path is more dangerous than landing in place | Over people, water without flotation plan, dense forest, or moving vehicles |
Selecting the right mode near controlled airspace and people
- Near people: Prefer modes that do not transit over uninvolved persons. Hover-in-place over a clear pad may beat RTH across a crowd. Landing in place on a clear roof pad may beat RTH across a street.
- Near controlled airspace / aerodromes: RTH paths that climb into a control zone or drift toward final approach can create a crewed-traffic conflict. Brief and set altitudes carefully; ensure authorization conditions and lost-link expectations match what ATC/NAV CANADA procedures require for the operation.
- Obstacle-rich sites: RTH altitude must clear the tallest obstacle on the return path with margin—or RTH becomes a wire-strike machine.
- Always verify home point after relocating the GCS. Wrong home + RTH is a classic flyaway-like outcome.
Pre-flight confirmation of lost-link behaviour is the single most important predictability control (matches practice-bank teaching: configure RTH/hover/land before you need it).
Flyaway recognition and response
A flyaway is an event in which the RPA departs controlled flight intent—the pilot cannot effectively control the aircraft and it leaves the planned operating volume (or is about to). Causes include control-system failure, severe GNSS/magnetometer faults, incorrect failsafe settings, motor failure inducing uncommanded flight, or lost link without a safe contingency.
Recognition cues
- Aircraft ignores control inputs or moves opposite to commands
- Rapid uncommanded climb, acceleration, or heading change
- Telemetry shows aircraft leaving geofence or planned cylinder while stick inputs do nothing
- Atti/GNSS mode faults with diverging position
Immediate response priorities
- Attempt recovery — mode changes, RTH command, attitude mode, motion controls per manufacturer emergency procedure; note what works.
- Maintain visual as long as possible (PIC/VO)—call out bearing and estimated altitude/distance.
- Protect people — warn bystanders, stop traffic if you have marshals, never chase under spinning props.
- Predict path — wind drift, last heading, RTH target if partially functioning.
- Communicate — notify the right authorities early if the aircraft may enter sensitive airspace or hit a populated area (below).
- Do not create a second hazard — launching a second drone into the same volume without a plan can worsen the mid-air picture.
Who to contact
| Situation | Contact |
|---|---|
| Aircraft may enter / is in controlled airspace or conflict with aerodrome traffic | ATC / the appropriate air traffic unit as soon as practicable; follow local emergency aviation reporting practice |
| Immediate ground injury, fire, or major property threat | Emergency services (e.g., 911) |
| Regulatory occurrence (accident/incident thresholds) | Transport Canada as required under Part IX reporting (see Section 11.4); TSB when thresholds met |
| NAV CANADA authorization conditions | Comply with any notification terms in the RPAS Flight Authorization |
Do not assume “no one was hurt, so silence is fine” for a flyaway that entered controlled airspace or created a serious aviation hazard. Practice-bank framing: report the occurrence and notify applicable authorities—not only the manufacturer.
Emergency landing zone selection (in the moment)
When you still have partial control or are choosing a forced landing:
- Prefer pre-briefed ELZs from the site survey
- Prioritize people first, then property, then the aircraft
- Avoid roads with moving traffic, power lines, glass facades, and fuel storage
- Accept a hard landing in a clear field over a soft landing on a playground
- After any hard landing or termination, treat the aircraft as unserviceable until inspected
See-and-avoid continuous; right of way to crewed aircraft
RPAS operations depend on detect-and-avoid that is largely see-and-avoid by the pilot and visual observers. Continuous visual vigilance is not optional during “automated” mapping grids.
Crewed aircraft always have right of way. If a helicopter, airplane, or ultralight appears on a conflicting path:
- Descend, land, or manoeuvre the RPA to remain well clear
- Do not climb into the traffic
- Do not assume the crewed pilot sees your small multirotor
- Resume only when the conflict is gone and the site is still valid
CAR 901.16 — Flight safety themes
CAR 901.16 is taught as a flight safety obligation family: operate the RPAS so as not to endanger aviation safety, people, or property—core “do not create a hazard” duty that sits underneath every privilege. In emergencies, 901.16 thinking means your recovery action should reduce total risk, not protect the airframe at the expense of a crowd.
Formation — CAR 901.36
CAR 901.36 addresses formation flight of RPAS. Teaching points for Advanced candidates:
- Formation is restricted/regulated—you do not freestyle multi-aircraft choreography because it looks good on social media.
- Without meeting the applicable conditions/authorizations, do not operate in formation.
- Formation multiplies mid-air and lost-link complexity; emergency procedures must cover more than one airframe.
Exam posture: if a scenario describes two or more RPAs flying as a coordinated formation without proper authority, the correct answer is that the operation is not allowed under ordinary Advanced assumptions.
Multiple RPA — CAR 901.40
CAR 901.40 addresses operating more than one RPA at a time. Core idea: a single pilot cannot simply “multi-box” unlimited aircraft under basic Advanced privileges. Limits and conditions apply so that control, see-and-avoid, and emergency handling remain effective.
| Concept | Operational meaning |
|---|---|
| One PIC attention model | You must be able to maintain control and safety responsibilities for what you operate |
| 901.40 limits | Multiple simultaneous RPA operations are constrained by regulation—not only by transmitter channels |
| Emergencies | Two aircraft lost-link plans can conflict; plan or avoid multi-aircraft until compliant |
Integrated emergency brief (say this out loud before launch)
- Lost-link mode is X; RTH altitude is Y; home point verified at Z.
- ELZ-1 is …; ELZ-2 is ….
- If crewed traffic appears, we land/clear immediately.
- If flyaway toward the airport/control zone, we call ATC/appropriate unit and 911 if ground risk.
- No formation / no multiple RPA outside 901.36 / 901.40 compliance.
- After any emergency landing, safe scene, then records and reporting (next section).
Bottom line: Program lost-link for the site, not for the demo video. Recognize flyaways early, protect people, call ATC/emergency services/TC as the situation demands, keep eyes outside, yield to crewed aircraft, and stay inside formation and multiple-RPA rules while you still have a controllable fleet.
Before flight, what is the most important measure to ensure a predictable response if command-and-control is lost?
An RPA flyaway may enter a control zone near a towered airport. Beyond attempting recovery, what contact priority is most appropriate?
Which statement correctly combines right-of-way, 901.16 flight-safety themes, and multi-aircraft rules?