Pegasus B738 at Istanbul on Jan 7th 2020, runway excursion on landing

Last Update: September 16, 2021 / 19:36:29 GMT/Zulu time

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Photo of Pegasus Airlines TC-CCK, Boeing 737-800 — Pegasus Airlines TC-CCK, Boeing 737-800 (Photo credit: Ian A Gratton / Flickr / License: CC by)

Incident Facts

Date of incident
Jan 7, 2020

Classification
Incident

Cause
Runway excursion on landing

Airline
Pegasus Airlines

Flight number
PC-747

Departure
Sharjah, United Arab Emirates

Destination
Istanbul Sabiha Gokcen, Turkey

Aircraft Registration
TC-CCK

Aircraft Type
Boeing 737-800

ICAO Type Designator
B738

Airport
Sabiha Gökçen International Airport, Istanbul

Airport ICAO Code
LTFJ

A Pegasus Airlines Boeing 737-800, registration TC-CCK performing flight PC-747 from Sharjah (United Arab Emirates) to Istanbul Sabiha Gokcen (Turkey) with 164 people on board, landed on Sabiha Gokcen Airport's runway 06 at 09:09L (06:09Z) but shortly after touchdown veered left and came to a stop with all gear on soft ground off the left runway edge about 1000 meters/3330 feet down the runway. The aircraft was evacuated via slides. There were no injuries, the damage to the aircraft is being assessed.

Istanbul's Governor's Office reported the incident occurred due to bad weather. The airport is currently closed, flights are being redirected. The occurrence is being investigated.

The airline reported the aircraft suffered a runway excursion after landing, all occupants disembarked safely. An investigation has begun.

In September 2021 the Turkish Ulasim Emniyeti Inceleme Merkezi (UEIM, Turkish Accident Investigation) created their website and released their first ever final report in Turkish only (Editorial note: to serve the purpose of global prevention of the repeat of causes leading to an occurrence an additional timely release of all occurrence reports in the only world spanning aviation language English would be necessary, a Turkish only release does not achieve this purpose as set by ICAO annex 13 and just forces many aviators to waste much more time and effort each in trying to understand the circumstances leading to the occurrence. Aviators operating internationally are required to read/speak English besides their local language, investigators need to be able to read/write/speak English to communicate with their counterparts all around the globe).

The UEIM concluded the probably causes of the serious incident were:

Human Factors as result of the captain's fault implementation of cross wind landing technique causing a hard touchdown on the runway subsequently steering the aircraft off the runway by applying rudder and ailerons the wrong way with the first officer reacting late.

In addition the report of windshear by previous landing traffic as well as frequent changes of wind direction and intensity are considered contributing factors.

The UEIM listed following main findings:

- pilots were properly licensed and met all regulations, the aircraft met all requirements

- the captain did not apply the proper crosswind landing technique

- a SINK RATE warning occurred twice due to incorrect use of the controls

- the aircraft touched down at +2.605G

- Rudder input was provided to turn the aircraft into the wind instead of counteracting the weathercocking effect

- asymmetric brakes were not used

- the runway excursion is the result of the captain's left rudder application

- the first officer did not intervene

- 24 hours to clear the runway is too long

The UEIM analysed that fatigue was not a factor into the serious incident. Vref had been computed to 142 KIAS, with the wind corrections Vapp was computed at 157 KIAS. According to FDR and CVR data the aircraft performed a stabilized ILS approach to runway 06. At 518 feet AGL the autopilot was disconnected. At 404 feet AGL the airspeed increased to 167 KIAS and reduced to 151 KIAS one second later. Autothrottle gets disconnected at 247 feet AGL, the aircraft is above the glideslope by about half a point, winds at that point 36 knots from 018 degrees, airspeed 169 KIAS. At 197 feet AGL the airspeed is 157 KIAS, winds at 33 knots from 022 degrees.

At 125 feet AGL and 98 feet AGL SINK RATE warnings occurred following large nose down inputs (4 degrees), sink rates above 1000 fpm were recorded between 125 and 57 feet AGL, the aircraft descended 0.6 points below the glideslope and 0.3 points left of the localizer. The aircraft is pitched up by 3 degrees, the airspeed drops to 142 KIAS (15 knots less than required), the aircraft is one dot below the glide and descends at 850 fpm.

The aircraft touched down on the left side of the runway at about 150 KIAS at 681 fpm, engines at 48/44% N1 without being pulled back to idle, the aircraft touched down at +2.605G due to insufficient nose up. The aircraft bounced. With the winds from the left ailerons are applied to the right, but no right rudder is being used to steer the aircraft onto the center line. The aircraft touched down a second time at 6.7 degrees right bank and 3 degrees nose down resulting in +1.6G vertical acceleration. Engines are reduced to idle, full aileron to the right and 5 degrees left rudder are applied, maximum reverse thrust is being applied. Autobrakes engage.

Related NOTAM:
A0101/20 NOTAMN
Q) LTBB/QMRLC/IV/NBO/A /000/999/4054N02919E005
A) LTFJ B) 2001070626 C) 2001070820 EST
E) RWY 06/24 CLSD TO TFC.

Metars:
LTFJ 070850Z 03024G35KT 6000 -SHRA BKN009 BKN030 06/04 Q1015 NOSIG RMK RWY24 01024KT=
LTFJ 070820Z 03025G38KT 6000 -SHRA BKN009 BKN030 06/04 Q1015 NOSIG RMK RWY24 02024KT=
LTFJ 070750Z 03025G37KT 6000 -SHRA BKN009 BKN030 06/05 Q1015 NOSIG RMK RWY24 01025G36KT=
LTFJ 070720Z 03027KT 3900 SHRA BKN009 BKN030 06/05 Q1014 BECMG TL0820 7000 RMK RWY24 02023G35KT=
LTFJ 070650Z 03026G36KT 7000 SHRA BKN009 BKN030 06/05 Q1014 BECMG TL0750 NSW SCT011 BKN025
LTFJ 070620Z 03027G37KT 8000 -SHRA SCT011 BKN030 BKN080 06/04 Q1014 NOSIG
LTFJ 070550Z 03024G36KT 7000 -SHRA SCT011 BKN030 BKN080 06/05 Q1014 NOSIG
LTFJ 070520Z 03028G38KT 7000 -SHRA SCT011 BKN030 BKN080 06/05 Q1013 NOSIG RMK RWY24 01022KT
LTFJ 070450Z 03023G33KT 7000 -SHRA SCT011 BKN030 BKN080 06/05 Q1013 NOSIG RMK RWY24 02023KT
LTFJ 070420Z 03026G37KT 7000 -SHRA SCT011 BKN030 BKN080 06/05 Q1013 NOSIG
LTFJ 070350Z 03026G37KT 8000 -SHRA SCT011 BKN030 BKN080 06/05 Q1012 NOSIG
LTFJ 070320Z 03025G36KT 9999 -SHRA SCT011 BKN030 BKN080 06/05 Q1012 NOSIG

The aircraft off the runway (Photo: Ömer Faruk Meydanal):

Overview:

The aircraft sunk into the soft and wet ground:

Ground tracks:

Map (Graphics: AVH/Google Earth):