Date:	Thursday 9 November 2017
Time:	20:53
Type:	de Havilland Canada DHC-8-402Q Dash 8
Owner/operator:	Air Canada Express
Registration:	C-GYJZ
MSN:	4524
Year of manufacture:	2016
Engine model:	Pratt & Whitney Canada PW150A
Fatalities:	Fatalities: 0 / Occupants: 56
Aircraft damage:	Substantial, repaired
Category:	Accident
Location:	Toronto City-Billy Bishop Airport, ON (YTZ) -   Canada
Phase:	Landing
Nature:	Passenger - Scheduled
Departure airport:	Montreal-Pierre Elliott Trudeau International Airport, QC (YUL/CYUL)
Destination airport:	Toronto City-Billy Bishop Airport, ON (YTZ/CYTZ)
Investigating agency:	TSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
A DHC-8-402 aircraft operated by Jazz Aviation, was conducting Air Canada Express flight 7977 from Montreal-Pierre Elliott Trudeau Airport to Toronto City Airport, Canada.
At about 20:50, while on approach to runway 26 at Toronto City Airport, the aircraft experienced turbulence. As a result, the airspeed fluctuated rapidly during the approach.
Jazz standard operating procedures (SOPs) for stable approaches allow for a deviation of -5 to +10 knots from the planned approach speed once the aircraft is below 500 feet above ground level (AGL) on approach. However, the speed of the occurrence aircraft’s approach varied from 119 to 141 knots. Because the speed deviations resulted from momentary wind gusts, the flight crew considered the approach to be stable.
Once the aircraft was below 100 feet AGL on approach, it encountered momentary wind shear as a result of a wind gust, causing its airspeed to decrease. The aircraft touched down and the pilots reacted by advancing the power levers to a maximum of 42.5% and 40% on the left and right engines, respectively.
The airplane was then caught in a wind shear, causing the airspeed to increase. The power levers were retarded through the flight idle gate position to the propeller discing detent position. However, the momentary increase in torque and airspeed caused the aircraft to become airborne again, up to 4.5 feet above the runway, for about 2.75 seconds.
The propeller blade angles moved through the ground-idle range into the disc position, which caused a significant loss of lift. The wind shear decreased, and the combined reduction in lift resulted in the aircraft firmly contacting the runway.
The vertical loads on landing exceeded 5.5g, which is the force at which both flight recorders stop simultaneously. Subsequently, the FDR caution light illuminated. The aircraft then taxied to the gate as normal.
Following consultation with the operator’s maintenance via telephone, the flight crew conducted a visual inspection of the aircraft; no abnormalities were detected. It was then decided that a hard landing maintenance inspection was not required, and the aircraft was dispatched under MEL authority for the FDR caution light that remained illuminated. After the departure on the return flight to Montreal, the flight crew requested that the aircraft be inspected on arrival due to a potential hard landing. When maintenance personnel in Montreal brought the aircraft into the hangar, airframe damage to the aft right fuselage and the right main landing gear was discovered.

No probable cause statement was published by TSB Canada in this limited-scope, fact-gathering investigation.

01:24 UTC / 20:24 local time:
CYTZ 100124Z AUTO 30021G29KT 9SM -RA FEW036 SCT055 SCT067 OVC098 02/M03 A2992 RMK SLP135

02:00 UTC / 21:00 local time:
CYTZ 100200Z AUTO 31021G32KT 9SM FEW030 SCT080 01/M05 A2996 RMK PRESRR SLP150

TSB A17O0243

Other occurrences involving this aircraft

2 October 2023	C-GYJZ	Jazz Air, opf Air Canada Express	0	CYVR - Vancouver Intl - Vancouver		non
Litium battery thermal event

photo (c) TSB Canada; Montreal-Pierre Elliott Trudeau International Airport, QC (YUL/CYUL); 09 November 2017

Date/time	Contributor	Updates