Incident Boeing 737-8SH (WL) 9XR-WR, Tuesday 30 January 2018

You can contribute by submitting additional or updated information.

Date:	Tuesday 30 January 2018
Time:	04:10
Type:	Boeing 737-8SH (WL)
Owner/operator:	RwandAir
Registration:	9XR-WR
MSN:	41357/6415
Year of manufacture:	2017
Engine model:	CFMI CFM56-7B
Fatalities:	Fatalities: 0 / Occupants: 0
Other fatalities:	0
Aircraft damage:	Minor
Category:	Incident
Location:	Addis Ababa-Bole Airport (ADD/HAAB) - Ethiopia
Phase:	Standing
Nature:	-
Departure airport:	Kigali Airport (KGL/HRYR)
Destination airport:	Addis Ababa-Bole Airport (ADD/HAAB)
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
On 30 January, 2018, a Boeing 737-800, registration 9XR-WR passenger transport aircraft operated by RwandAir Limited performing flight from Kigali, Rwanda to Addis Ababa landed at Bole International Airport at 03:27 UTC. After landing the aircraft was instructed to proceed to the cargo apron due to high traffic on the main apron. Upon arriving at the cargo apron the airport marshaller guided it to a stopping position. After engine shutdown the marshaller managed by himself to put the chocks in because the ground handling agent (ICAS) was not present at the parking area to meet the aircraft due to misinformation on the expected arrival time of the aircraft.
The pilot released parking brake after receiving hand signals from the marshaller that chocks are in position. Further the marshaller and the “Follow me” vehicle left the area for another duty. At 04:10 UTC the aircraft rolled by itself forward slowly until its left engine inlet cowl collided with a flood light mast and its concrete barrier. An interview with eyewitness confirmed that chocks were not installed at the front side of the wheels to resist the forward rolling of the wheels due to the down slope of the apron but at the back.
The bottom part of the inlet cowl outer barrel skin got scratched by the concrete barrier while it’s left side deformed by the flood light mast.

Probable Cause of the incident
The most probable cause of the incident is improper installation of chocks considering the slope of the apron.
Contributing Factors
- Misinformation on the arrival time of the flight by the ground handling agent.
- Down slope of the unmarked parking apron
- Not sending of the flight movement message by the operator to the handling agent immediately after departure

Accident investigation: