August 12, 2021

Incident at 5251N / 08637W (Communication navigation surveillance/air traffic system)

A Sifec North Inc. Beech 200 (C-GSNI) from Whale Cove, NU (CYXN) to Lachute, QC (CSE4) was instructed to descend from FL290 to FL270 in airspace that was under the jurisdiction of another controller, without prior coordination. No loss of separation or impact on operations.

January 24, 2021

Incident at In the vicinity of: WIARTON ON

There were multiple reports of an emergency locator transmitter (ELT) signal, from FL240 to FL290, between Wiarton, ON, and St. Catharines, ON. In addition, there were several low level ELT reports at A030, near Bobcaygeon, ON. The Joint Rescue Coordination Centre (JRCC) Trenton was advised.

September 27, 2021

Incident at 5900N / 08130W

A China Eastern Airlines Boeing 777-300 (B2023/CES588) from New York/John F. Kennedy Intl, NY (KJFK) to Shanghai/Pudong, China (ZSPD) reported severe turbulence. The aircraft descended and reported smooth air at FL280 and FL290. No impact to operations.

August 9, 2021

Incident at 7350N / 09431W

A Government of Canada, Department of National Defence Lockheed C-130 (CFC4259) from Resolute Bay, NU (CYRB) to Trenton, ON (CYTR) was cleared to FL290, but was observed on the automatic dependent surveillance – broadcast (ADS-B) at FL297. The aircraft returned to FL290 when queried. There was no traffic and no impact to operations.

July 9, 2021

Incident at 5021N / 11413W

A Pentastar Air Ltd. Cessna 525B (C-FNCB) from Calgary, AB (CYYC) to Glacier Park, MT (KGPI) was instructed to climb to FL270. The aircraft was observed to level at FL290. No impact on operations.

May 26, 2021

Incident at GELBO intersection

The Edmonton area control centre (ACC) received an estimate for a United States Air Force Air Mobility Command Boeing C17A (RCH615) from Thule Air Base, Greenland (BGTL) to McGuire Field/Wrightstown, NJ (KWRI) indicating an altitude of FL340. At GELBO, RCH615 entered the Edmonton ACC airspace at FL290. No impact to operations.

November 3, 2020

Incident at 5NM W RABIK intersection

An Aerospace Hawker 800XP (MVNES), registered in the United Kingdom, from Montreal/Pierre Elliott Trudeau, QC (CYUL) to Montreal/Pierre Elliott Trudeau, QC (CYUL), climbing from FL290 towards FL350, 5NM from RABIK, suddenly executed a turn of about 60 degrees to the south. When questioned, the aircraft mentioned having an autopilot problem. The aircraft was reauthorized en route. No impact on operations.

January 20, 2020

Incident at 5804N / 07726W (Communication navigation surveillance/air traffic system)

An Air Inuit Boeing 737-2S2C (C-GAIG/AIE780) from La Grande-Rivière, QC (CYGL) to Puvirnituq, QC (CYPX) was cleared to descend to FL290. The aircraft read back FL280 and the readback error was not caught by the air traffic services (ATS) unit. No impact on operations.

January 22, 2020

Incident at 65NM BROADVIEW SK (YDR) VOR/DME (Communication navigation surveillance/air traffic system)

A SkyWest Airlines Embraer ERJ 170-200LR (SKW4560) on a flight from Minneapolis/St. Paul Intl, MN (KMSP) was cleared to FL290 by the Winnipeg area control centre (ACC) controller and the clearance was read back correctly. The controller subsequently updated the electronic flight strip (EFS) with FL320 as that was the altitude the controller had intended to clear the aircraft to. SKW4560 was observed descending through FL308 and was queried by the controller. SKW4560 was re-cleared to FL300. No impact to operations.

March 7, 2020


TSB Report #A20A0011: C-FDSN, an Airbus A320 operated by Air Canada was conducting flight ACA680 from Toronto Lester B Pearson International Airport, ON (CYYZ) to St John’s International Airport, NL (CYYT). While in cruise at FL350, the number 2 engine rolled back to approximately 54% N1, while the number 1 engine remained at 92% N1. The crew descended to FL290 with auto thrust commanded to 85% and both engines responded. The flight continued to destination without further incident. Maintenance is investigating.

March 12, 2020


An Empire Airways Cessna 560 Citation V (JKR72) from Teterboro, NJ (KTEB) to Halifax/Stanfield, NS (CYHZ) read back incorrect altitude.
UPDATE AOR-263314-V3: JKR72 was cleared to FL290, pilot discretion, and advised next controller that aircraft was descending to 5000ft. No loss of separation or impact to operations.

March 3, 2020

Incident at 4930N / 04756W

An American, corporately registered Learjet 36A (N81GJ) from St. Johns, NL (CYYT) to Hamburg, Germany (EDDH) descended without clearance from FL350 to FL290 and proceeded direct CYYT due to a medical emergency.

February 13, 2020

Incident at 4525N / 06220W

Severe turbulence reported at FL310 by an Aer Lingus Ltd. Airbus A330-300 (EIN104) from New York/John F. Kennedy, NY (KJFK) to Dublin, Ireland (EIDW). Aircraft declared "mayday" and executed an immediate descent to FL290. No injuries or damage. No impact on operations. National Operations Centre (NOC) advised.
Update TSB Report #A20A0008: EI-GAJ an Airbus 330-300 aircraft operated by Aer Lingus was conducting flight EIN104 from John F Kennedy (KJFK) airport, New York, to Dublin airport (EIDW), Ireland. While in cruise at FL310 and approximately 50 NM NE of Halifax, Nova Scotia, the aircraft encountered severe turbulence. The crew declared a MAYDAY and immediately began a descent to FL290. There were no injuries to the crew or passengers nor damage to the aircraft. The aircraft continued to destination.

November 17, 2019

Incident at S OBRET intersection

During initial contact with the lower-level sector, a Bombardier Inc. Bombardier BD-700-1A10 (C-GFQR/BBA34) from Montreal/Pierre Elliott Trudeau Intl, QC (CYUL) to Montreal/Pierre Elliott Trudeau Intl, QC (CYUL) reported that it was descending to FL270, even though it had received and read back clearance from the upper-level sector to descend to FL290. No loss of separation and no impact on operations.

October 4, 2019


A Government of Canada, Department of National Defence Lockheed C-130 (CFC2540) on a flight from Trenton, ON (CYTR) to St. Johns, NL (CYYT) indicated they had a cracked windshield and needed to descend from FL290 to FL200. CFC2540 requested a diversion to Trenton, ON (CYTR). No emergency declared. No impact.

July 10, 2019

Incident at 50NM GASPÉ QC VOR/DME (YGP)

A Boeing KC-135R (ROMA65) from Bangor, ME (KBGR) to Salt Lake City, UT (KSLC) had an engine malfunction indication, requested to dump fuel and return to KBGR. The fuel dump occurred from 0850Z to 0910Z at FL290. No emergency declared. No impact on operations. Affected agencies notified.

July 11, 2019

Incident at 52NM MANIWAKI QC NDB (YMW)

After having received and correctly read back clearance to descend to FL290, an Air Canada Airbus A320-214 (C-FXCD/ACA396) from Calgary, AB (CYYC) to Montreal/Trudeau, QC (CYUL) was seen passing FL280 in descent. No impact on operations.

June 16, 2019


An Air Transat aircraft, make and model unknown (TSC267+), origin and destination unknown, was given and read back FL290 by the LE sector. TSC267+ checked in with the GR sector while descending to FL270. No impact on operations, aircraft was still at FL360 during the check-in.

July 30, 2019


A Philippine Airlines Boeing 777-300 (RPC7782/PAL116) from Manila, Philippines (RPLL) to Vancouver, BC (CYVR) was at FL350 and started descending without clearance. Controller noticed and then cleared the aircraft to FL290. No impact to operations.

July 17, 2019

Incident at 5024N / 12627W

A China Eastern Airlines Airbus A330-243 (B5952/CES597) from Shanghai Pudong, China (ZSPD) to Vancouver, BC (CYVR) started to descend to FL290 without clearance. No impact to operations.

April 13, 2019

Incident at AGNOB intersection

An Alitatlia Airbus A330-200 (AZA65F) from Toronto/Pearson, ON (CYYZ) to Rome, Italy (LIRF) climbing to FL290 received a traffic alert and collision avoidance system (TCAS) resolution advisory (RA) from crossing traffic at FL300. They had the traffic visually and there was no operational impact.
UPDATE: AOR-249508-V2: Traffic was not passed. AZA65F had the traffic visually and there was no operational impact.

January 27, 2019


TSB Report #A19F0024: C-FTVF, a Boeing 737-800 aircraft operated by Air Transat, was conducting flight TSC447 from Holguin/Frank País Intl (MUHG), Cuba to Toronto/Lester B. Pearson Intl (CYYZ), ON with 6 crew members and 183 passengers on board. During cruise flight at FL290, approximately 90 nm east-southeast of Pittsburgh Intl (KPIT), PA, the flight encountered severe turbulence for approximately 30 seconds. Altitude and pitch variations were minor. Speed variations were +/- 10 kts, and the aircraft experienced rolls of approximately 30° that were managed by the auto-pilot. The flight crew requested and was authorized to FL270, and the aircraft continued to destination without further incident. There were no injuries. The operator’s maintenance inspected the aircraft in accordance with the Aircraft Maintenance Manual (AMM). No defects were found, and the aircraft was returned to service.

August 29, 2019

Incident at 4905N / 09534W

A Federal Express Corporation Airbus A310-324 (N811FD/FDX134) on a flight from Memphis Intl, TN (KMEM) to Winnipeg/James Armstrong Richardson Intl, MB (CYWG) was northwest bound descending from FL380 to FL290 and advised responding to a traffic alert and collision avoidance system (TCAS) resolution advisory (RA). The traffic was a southeast bound Air China Cargo Company Boeing 777-200 (B2094/CAO1053) on a flight from Anchorage Intl, AK (PANC) to Chicago/OHare Intl, IL (KORD) at FL330 which passed 5.1NM south of FDX134. No other impact to operations.
Update TSB Report #A19C0107: N811FD, a Airbus A310-324 aircraft operated by FedEx, was conducting cargo flight FDX134 from Memphis Intl (KMEM), USA to Winnipeg/James Armstrong Richardson Intl (CYWG), MB. At approximately 100 nm SE of CYWG, FDX134 requested a descent from flight level 380 and was cleared to flight level 290 by Winnipeg Centre Area Control Centre (ACC). FDX134 subsequently started the descent. ACC then cleared B-2094, a Boeing 777-FFT operated by Air China Cargo as flight CAO1054 at flight 330, to turn right 10 degrees to provide separation with FDX134. As FDX134 was descending through flight level 340, the crew of FDX134 asked ACC about traffic ahead of them. During the radio transmission regarding the traffic, FDX134 received a TCAS TA/RA to climb. FDX134 complied with the TA/RA, notified ACC of the manoeuvre and advised once clear from the traffic. FDX134 continued for an uneventful landing at CYWG. Review of the available radar information indicates that the nearest distance between the two aircraft was 5.1 miles laterally and 600 feet vertically. Minimum separation requirements are 5 miles or 1000 feet.

August 17, 2019

Incident at 6010N / 13730W

The pilot of a United States Air Force Boeing CC-177 Globemaster III (COKE141) from Eielson Air Force Base, AK (PAEI) to Tacoma/Joint Base Lewis–McChord, WA (KTCM) communicated they were receiving door warning indications and requested descent to FL240. Pilot did not declare an emergency at this time and said they would have a better assessment once level at FL240. Aircraft was handed off to Anchorage while still in descent and leaving FL290, approximately. Anchorage controller was made aware of the issues reported by the pilot prior to the hand off. No impact to operations.

February 7, 2019


After establishing contact with the Winnipeg Area Control Centre (ACC), a SkyWest Airlines Bombardier CL-600-2D24 (Series 900) (SKW4559) from Minneapolis/St. Paul International, MN (KMSP) to Winnipeg/Richardson International, MB (CYWG) was cleared to continue on the NORAK TWO arrival into CYWG, and was subsequently observed beginning their descent out of FL360 without a descent clearance. After a query from the controller, the aircraft was cleared to FL290. No operational impact.

September 19, 2019


A Southeast Airmotive Corporation aircraft (flight SPUR81), an Ethiopian Airlines aircraft (flight ETH503), and an Air France aircraft (flight AFR650) reported severe turbulence at FL290, FL330-FL350 and FL360 in an area bounded by Halifax, NS VOR/DME (YHZ), Grindstone (Îles-de-la-Madeleine), QC VOR/DME (YGR) and Sydney, NS VOR/DME (YQY). SIGMET G1 issued after Halifax (HZ) Flight Service Station (FSS) was advised of each of the reports. Aircraft continued on route as filed.

June 24, 2019

Incident at TUSKY intersection

An Air India Boeing 787-8 (AIC104) reported severe turbulence at FL290, aircraft climbed to FL330. Reported to the Flight Information Centre (FIC).

September 28, 2019

Incident at 5700N / 03130W

A WestJet Boeing 737-7CT (C-FWSK/WJA31) on a flight from Glasgow, Scotland (EGPF) to Halifax/Stanfield Intl, NS (CYHZ) declared a medical emergency with North Atlantic Traffic Services (NATS), and requested a diversion to Reykjavik, Iceland (BIKF) as it exited NATS airspace and entered Canadian airspace. Air traffic services (ATS) were unable to provide the requested clearance due to traffic, and the aircraft was advised that there was negative traffic at FL290. The aircraft descended to FL290 using contingency procedures, at which point a clearance direct to BIKF was issued by Gander Area Control Centre (ACC). The aircraft landed safely at 1214Z. No impact to operations.

August 3, 2019

Incident at 5630N / 05920W

An American, corporately registered Boeing 737-300 (N604SW) from Portland Intl Jetport, ME (KPWM) to Keflavik, Iceland (BIKF) was cleared from FL370 to FL350 due to traffic. After initially levelling off at FL350, the aircraft descended from FL350 without clearance, and contacted air traffic control (ATC) to indicate that they were descending to their expected oceanic flight level. Aircraft was re-cleared to FL290. No traffic. No impact to operations.

July 15, 2019

Incident at 4440N / 06550W

A WestJet Boeing 737-7CT (C-GWJF/WJA882) from Toronto/Pearson, ON (CYYZ) to Halifax/Stanfield, NS (CYHZ) was cleared to FL290 and the pilot read back that they were descending to FL290. The aircraft checked in with the low sector and reported descending to FL280. Controller asked the pilot to confirm their cleared level and they confirmed FL280. No impact on operations, safety was not jeopardized, no separation issues.

May 30, 2019

Incident at 4244N / 06444W

An Emirates Boeing 777 300 series (A6EGF/UAE210) from Newark, NJ (KEWR) to Athens, Greece (LGAV) reported continuous moderate to severe turbulence. The aircraft descended from FL330 to FL290.

Incident at 4256N / 06443W

A Delta Air Lines Boeing 777-233LR (N860DA/DAL84) from Atlanta, GA (KATL) to Paris, France (LFPG) reported continuous moderate to severe turbulence. The aircraft descended from FL310 to FL290.

May 21, 2019


A Jazz Bombardier CL-600-2D24 (series 900) (C-GDJZ/JZA8630) from Ottawa/MacDonald-Cartier, ON (CYOW) to Halifax/Stanfield, NS (CYHZ) cleared to descend to FL290, was observed descending to FL280 without air traffic control (ATC) clearance. No loss of separation.

November 15, 2018


A Bombardier CL-600-2B19 (100 series) operated by Jazz (C-GJZZ/JZA8033), flying from Philadelphia (KPHL), PA, to Montreal/Pierre-Elliott-Trudeau (CYUL), QC, declared an emergency. It reported mechanical issues with the right engine and requested emergency vehicle response. The aircraft landed without incident at 0003Z. No operational impact.
UPDATE from Airworthiness: A Civil Aviation Safety Inspector (CASI) looked into this occurrence. Flight Crew conducted an in-flight shut down during descent due to a low oil pressure on the right engine. During maintenance troubleshooting, it was noted that the preformed packing for the air turbine starter (ATS) carbon seal assembly (assy) outer body was missing. A packing was installed, an oil leak check performed, and the aircraft released to service. An Safety Management System (SMS) report was submitted and the event investigated by the Company.
Update TSB #A18F0268: C-GJZZ, a Bombardier CL-600-2B19 (CRJ200) aircraft operated by Jazz Aviation LP, was conducting flight JZA8033 from Philadelphia Intl (KPHL), PA to Montreal/Pierre Elliott Trudeau Intl (CYUL), QC with 3 crew members and 41 passengers on board. Approximately 25 minutes after the departure during cruise flight at FL290, the flight crew received a fluctuating oil pressure indication on the number 2 engine. Passing through 15 000 feet during the descent to CYUL, the flight crew elected to shut the number 2 engine (General Electric CF34-3B1) down since the oil pressure was decreasing and the oil pressure warning activated. The flight crew declared a PAN PAN, briefed the passengers, and completed a successful landing at CYUL without further incident. The operator’s maintenance found that the O-ring behind the number 2 starter seal was missing. A new seal with the O-ring was installed as per GE’s maintenance manual 72-61-00. The number 2 engine oil tank was serviced, engine runs were performed, and no leaks were found. The aircraft was returned to service.

July 11, 2018


An Air Canada Boeing 787-8 (C-GHPQ/ACA005) from Montreal/Pierre Elliott Trudeau Intl, QC (CYUL) to Narita Intl, Japan (RJAA) reported that it was climbing to FL290 during initial contact with the PO sector, even though it had received and read back clearance from sector LA to climb to FL280. No impact on operations.

February 25, 2018

Incident at 4813N / 06909W

An Etihad Airways Boeing 777-300 (ETD76T) on a flight from Chicago/O'Hare Int'l, IL (KORD) to Abu Dhabi, UAE (OMAA) reported severe turbulence at FL310. The aircraft requested and was cleared to FL290.

September 18, 2018

Incident at 34 NM SE THUNDER BAY ON (CYQT) (ATS operating irregularity)

A Skyservice Aviation Learjet 45 (C-GEJD) from Thunder Bay, ON (CYQT) to Toronto/Lester B. Pearson, ON (CYYZ) was cleared to FL280. The pilot's incorrect read back of FL300 was not caught by the controller. When checking in with the next sector, the controller stopped C-GEJD at FL290 due to traffic.


Multiple aircraft at FL260 to FL290 reported a strong emergency locator transmitter (ELT) signal in the vicinity of London, ON (CYXU). Trenton Joint Rescue Coordination Centre (JRCC) was advised.

August 16, 2018

Incident at yow 156 / 33

An Air Canada Rouge Airbus A319-114 (C-GBHR/ROU1704) from Toronto/Lester B. Pearson Int'l, ON (CYYZ) to Deer Lake, NL (CYDF) at FL330 declared a pressurization issue and requested to descend to FL290. At 1940Z, when reaching FL290, the aircraft advised that the pressurization was now stable and continued towards its destination without declaring an emergency. No operational impact.

June 20, 2018

Incident at 25NM TRENTON ON (CYTR)

An Air Canada Rouge Boeing 767-375 (C-FXCA/ROU1914) from Toronto/Pearson International, ON (CYYZ) to Barcelona/El Prat, Spain (LEBL) was climbing from FL290 to FL310 in the vicinity of Trenton, ON (CYTR) when the aircraft reported being struck by a laser 5 to 6 times. ROU1914 provided the controller with coordinates. Trenton, ON (CYTR) aerodrome officials were notified and the military police were called out.

May 2, 2018

Incident at 4909N / 09211W

A Jetport Inc. Bombardier BD-700-1A10 (C-FLGZ) from Sault Ste Marie, ON (CYAM) to Kenora, ON (CYQK) was instructed to descend to FL290 on heading 280 and correctly read back the clearance. C-FLGZ subsequently contacted the East Low Controller in descent through FL389, reported descending to FL280, and was issued further descent. No operational impact.

April 2, 2018


An Air Canada Airbus A320 (ACA413) en route from Montreal/Pierre Elliott Trudeau Int'l, QC (CYUL) to Toronto/Lester B. Pearson Int'l, ON (CYYZ) reported a strong emergency locator transmitter (ELT) signal descending through FL290-FL270 over Peterborough, ON (CYPQ). No other reports. No operational impact.

October 20, 2018

Incident at 25NM NW Albany (KALB)

TSB #A18F0241: C-FEJD, an EMB170-200 was being operated by Sky Regional Airlines as flight SKV7672 from Lester B. Pearson Intl - Toronto (CYYZ) to General Edward Lawrence Logan Intl - Boston (KBOS). During the climb through FL300 for FL310 the crew noticed the cabin altitude was at 8000 feet and in the amber caution range. A descent was requested and at FL290 the cabin altitude continued to rise with a Cabin Altitude High message. A full emergency descent was completed with a descent to 10000 feet. An emergency was declared by the crew with a request to divert to Albany International Airport (KALB). The aircraft landed on RWY28 KALB uneventfully with ARFF on standby. The aircraft was inspected and ferried to CYYZ for further maintenance.

October 7, 2018

Incident at 4702N / 08636W

An Air Bravo Corp. Pilatus PC-12 (AB237) from Hamilton, ON (CYHM) to Thunder Bay, ON (CYQT) was level at FL290 on the hand off from the Minneapolis (MSP) Area Control Centre when the Canadian Automated Air Traffic System (CAATS) estimate received by the Winnipeg Area Control Centre (WG ACC) indicated that AB237 was at FL280. No operational impact. No loss of surveillance separation.

October 3, 2018

Incident at 80NM Annette Island, AK VORTAC (ANN)

An Alaska Airlines Inc. Boeing 737 700 (N625AS/ASA7004) from Seattle-Tacoma Int'l Airport (Sea-Tac), WA (KSEA) to Ketchikan Int'l Airport, AK (PAKT) was observed on surveillance descending below FL290 without authorization. No operational impact.

December 27, 2018


The Winnipeg area control centre (ACC) controller instructed an Airsprint Inc. Cessna 525A (C-FIAS/ASP511) from Swift Current, SK (CYYN) to Calgary Intl, AB (CYYC) to climb to FL340 without coordination with the sector responsible for FL290 and above. No other aircraft in the vicinity and no impact to operations.

January 30, 2018

Incident at 5130N / 11139W

An Air Canada Embraer ERJ 190-100 IGW (ACA355) on a flight from Ottawa/MacDonald-Cartier, ON (CYOW) to Calgary, AB (CYYC) was cleared to descend to FL290 and read back the clearance limit. On contact with the next sector, the aircraft indicated they were cleared to FL240. The controller corrected the clearance limit prior to descent below cleared altitude.

December 22, 2018

Incident at 5613N / 04408W

At 1324Z an Aeroflot-Russian Airlines Boeing 777-M0ER (VQ-BQB/AFL100) from Sheremetyevo Intl Airport, Russia (UUEE) to New York/John F. Kennedy Intl Airport, NY (KJFK) descended from FL300 to FL280 without clearance. Opposite direction traffic of a Federal Express Corporation McDonnell Douglas MD-11F (N613FE/FDX9001) from Memphis Intl Airport, TN (KMEM) to Cologne Bonn Airport, Germany (EDDK) at FL290. AFL100 requested FL280 after it was asked to confirm flight level (FL).
Update TSB Report #A18A0098: VQ-BQB, a Boeing 777-300 aircraft operated by Aeroflot Russian Airlines, was conducting flight AFL100 from Moscow/Sheremetyevo Intl (UUEE), Russia to New York/John F. Kennedy Intl (KJFK), NY. N613FE, a McDonnell Douglas MD-11F aircraft operated by Federal Express, was conducting flight FDX9001 from Memphis Intl (KMEM), TN to Cologne-Bonn/Konrad Adenauer (EDDK), Germany. At approximate position 56°13 N / 044°08 W, AFL100 descended from FL300 to FL280 without a clearance. Opposing traffic was FDX9001 at FL290. Since the 2 aircraft did not establish the required vertical separation for 15 minutes before and after crossing tracks, a loss of separation occurred.

December 11, 2018

Incident at 4334N / 05925W

An Air India Boeing 777-300 (VTALM/AIC144) from Newark International, NJ (KEWR) to Chhatrapati Shivaji Maharaj International, India (VABB) reported severe turbulence at FL310, and descended to FL290. No injuries were reported and there was no impact to operations.

November 14, 2018

Incident at 4827N / 05802W

A United Airlines Boeing 777-200 (UAL82) from Newark International, NJ (KEWR) to Indira Gandhi International, India (VIDP) reported severe turbulence. The aircraft descended from FL290 to FL270. No issues were reported by the crew. No impact to operations.