Date:	Monday 12 June 2023
Time:	17:35 UTC
Type:	Boeing 737-8K5 (WL)
Owner/operator:	TUI Airways
Registration:	G-FDZK
MSN:	37258/3655
Year of manufacture:	2011
Fatalities:	Fatalities: 0 / Occupants: 187
Aircraft damage:	None
Category:	Serious incident
Location:	Manchester International Airport (MAN/EGCC) -   United Kingdom
Phase:	Approach
Nature:	Passenger - Scheduled
Departure airport:	Zakinthos Airport (ZTH/LGZA)
Destination airport:	Manchester International Airport (MAN/EGCC)
Investigating agency:	AAIB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
TUI Airways flight BY2163, a Boeing 737-8K5, made an unplanned descent during a go-around in adverse weather conditions at Manchester Airport.

The aircraft was flying back to Manchester Airport from Zakynthos in Greece. Thunderstorms had been forecast across most of the UK and the crew had taken extra fuel to account for possible extended routings or delays. The commander was the pilot flying.

As the aircraft approached Manchester the flight crew negotiated a routing to the north of the airport to avoid cumulonimbus clouds visible to the south. They were vectored onto the ILS approach for Runway 05R.

Their weather radar showed a thunderstorm cell moving left to right across the airport but they were below the base of the cloud and could see the runway. As the aircraft was handed from the approach controller to the tower controller, they were advised that the previous aircraft had gone around. The tower controller cleared the aircraft to land, stating “05R cleared to land, wind 160 degrees, 19 knots, recent gust 27 knots, heavy shower on the threshold”.

The pilots could still see the runway so decided to continue the approach. They reviewed their missed approach actions.

As the aircraft reached the decision height of 390 ft AMSL it entered heavy rain and the pilots lost visual reference. They described “hitting a wall of rain” and “it all going black outside”.

Both pilots called ‘go-around’ simultaneously. The commander pressed TOGA and manually advanced the thrust levers with the autopilot and autothrottle disconnected. Both pilots confirmed thrust was increasing. The co-pilot selected Flap 15 and with a positive rate of climb selected the landing gear UP. However, as the commander increased the pitch through 10°, he noticed the airspeed rapidly reducing.

Concerned that the aircraft may stall he applied a nose-down pitch input to prevent further speed loss. Initially he could not work out why the aircraft was not accelerating and climbing as he would expect during a go-around.

He recalled that ‘the airspeed was close to VREF, the trend vector was touching the top of the red and black band and the aircraft felt slow to react. After a few seconds he realised the acceleration and climb had stagnated so he started to add additional thrust. The EGPWS system then announced ‘don’t sink don’t sink’, and ‘pull up’ was displayed on the PFD.

The commander immediately applied full thrust and, as the speed increased, he increased the pitch attitude. Once safely climbing away they started to accelerate, retracted the flaps and reduced the thrust.

Once level at the missed approach altitude the pilots reviewed their options. They considered another approach to Manchester but ATC advised that subsequent aircraft had broken off the approach and the crew realised there would be a delay whilst the weather cleared.

They decided to divert to Newcastle where the weather was clear. The remainder of the flight was uneventful.

Both pilots commented that they were startled by the sudden loss of visual reference.

=AAIB Conclusion=
The slight descent and EGPWS caution during the go-around were caused by the commander reducing the pitch attitude in response to a loss of airspeed. The loss of airspeed was due to a change in wind direction caused by the approaching thunderstorm with insufficient thrust applied.

The go-around procedure requires the flight crew to verify sufficient thrust is set to achieve the climb performance during a go-around. The aircraft manufacturer considers a windshear escape manoeuvre to be an appropriate response in these circumstances".

There were no injuries to the 187 persons on board (6 crew and 181 passengers)

EGCC 121620Z AUTO 17004KT 100V220 9999 //////CB 26/16 Q1013
EGCC 121720Z AUTO 21005KT 180V240 9999 //////CB 26/18 Q1013 TEMPO SHRA
EGCC 121750Z AUTO 20005KT 130V240 9999 -TSRA //////CB 21/17 Q1014 RETS RETSGR RETSRA TEMPO 4000 TSRA
EGCC 121850Z AUTO 22006KT 9999 -TSRA //////CB 20/17 Q1016 TEMPO 3000 TSRA

1. AAIB Final report: https://assets.publishing.service.gov.uk/media/659d2a6e48baa2000ebbe386/Boeing_737-8K5_G-FDZX_01-24.pdf
2. https://www.flightradar24.com/data/aircraft/g-fdzx/
3. https://www.flightglobal.com/safety/tui-737-sink-alert-on-go-around-traced-to-insufficient-thrust-in-storm-winds/156446.article
4. https://planefinder.net/data/aircraft/G-FDZX
5. [photo dated 11.2.2023]: https://www.airport-data.com/aircraft/photo/001743868.html
6. https://en.wikipedia.org/wiki/Manchester_Airport

Date/time	Contributor	Updates
12-Jan-2024 09:24	Dr. John Smith	Added
12-Jan-2024 09:30	harro	Updated [Time, Aircraft type, Operator, Other fatalities, Narrative, Accident report]