Ibex CRJ7 near Fukuoka on Oct 30th 2019, cracked windshield

Last Update: October 28, 2020 / 12:31:35 GMT/Zulu time

Bookmark this article
Incident Facts

Date of incident
Oct 30, 2019

Classification
Incident

Cause
Cracked windshield

Airline
Ibex Airlines

Flight number
FW-16

Departure
Sendai, Japan

Destination
Fukuoka, Japan

Aircraft Registration
JA11RJ

Aircraft Type
Canadair CRJ-700

ICAO Type Designator
CRJ7

An Ibex Airlines Canadair CRJ-700, registration JA11RJ performing flight FW-16 from Sendai to Fukuoka (Japan) with 69 passengers and 4 crew, was enroute at FL340 about 150nm northeast of Fukuoka when one of the windshields cracked. The crew initiated an early descent to 10,000 feet levelling off at 10,000 feet about 14 minutes after leaving FL340, and continued to Fukuoka for a safe landing.

The occurrence aircraft was still on the ground about 36 hours after landing.

On Nov 1st 2019 Japan's TSB reported the aircraft was enroute at FL340 when the captain's windshield cracked. While working the checklists to deal with the crack and while descending the crew noticed the cabin pressure had dropped, the passenger oxygen masks dropped automatically, the crew initiated an emergency descent to 10,000 feet. The aircraft landed in Fukuoka without further incident. An investigation has been opened.

On Oct 28th 2020 the JTSB released their final report concluding the probable causes of the serious incident were:

It is highly probable that this serious incident occurred because an arcing occurred in the left windshield while the aircraft was flying at FL 340, and the PIC performed the operation to raise the cabin altitude in accordance with the check list, resulting in abnormal decompression inside the aircraft.

It is also highly probable that the abnormal decompression inside the aircraft occurred because irrespective of the flight altitude, the procedure in the check list would require the pilot to perform the set to climb the cabin altitude at the maximum climb rate without any exception.

The JTSB described the sequence of events:

At around 17:47, when the aircraft was cruising at FL 340, about 50 km east of Miho Airport, the PIC saw a flash near the left window. After that, EICAS displayed gL WINDOW HEATh (Caution*3). According to the check list, the PIC switched the gL WSHLD HEAT SWh from gLOWh to gOFF/RESETh, and when he set it to gLOWh again, the message disappeared.

At around 17:53, the PIC saw a flash near the left window again. After a while, in turn, EICAS displayed gL WSHLD HEATh (Caution). According to the check list, the PIC switched the gL WSHLD HEAT SWh from gLOWh to gOFF/RESETh, and when he set it to gLOWh again, the message disappeared. According to the PIC, at the moment, the cabin altitude was about 5,700 ft.

At around 17:56, when flying at FL 340 about 50 km southwest of Miho
Airport, the PIC found something like cracks in the left windshield. The PIC commenced dealing with the situation according to the check list (See the description in 2.7 (6)).

As the PIC decreased the cabin pressure manually according to the
check list, the cabin altitude started to increase.

At around 17:58, when the PIC was going to commence descending, EICAS displayed gCABIN ALTh (Caution), which soon turned into gCABIN
ALTh (Warning).

At around 17:59, the PIC commenced an emergency descent according to the check list. Considering the expansion of the crack in the windshield, the PIC had the aircraft descent to 10,000 ft at a descent rate of about 3,000 ft/min so as not to increase the aircraftfs air speed. According to the PIC, at the moment, the cabin altitude was about 12,400 ft.

At around 18:02, in an emergency descent, when the Aircraft was at around FL 260 and about 90 km southwest of Miho Airport, EICAS displayed gPASS OXY ONh (Caution) and the oxygen masks in the cabin were automatically deployed. According to the PIC and the FO, at the moment, the cabin altitude was about 14,000 ft, and the differential pressure was 5.2 psid.

At around 18:10, the aircraft reached (the flight altitude of) about 10,000 ft over near Iwami Airport and the cabin altitude also reached about 10,000 ft.

At 18:21, communicating with Fukuoka Approach, the PIC declared an emergency.

At 18:38, the aircraft landed at Fukuoka Airport.

The JTSB listed the relevant procedure:

Procedure in the check list

There were the following descriptions in the second volume
gABNORMAL PROCEDUREh of the AOM for the aircraft as regards the
check list to be followed when arcing, delaminated, shattered, or cracked
are found on the windshield, and the following are the excerpts.

‡@ ANTI-ICE, LH or RH WSHLD------------------------Affected side OFF
‡A PRESS CONT-----------------------------------------------MAN
‡B MAN RATE--------------------------------------------------INCR MAX
‡C MAN ALT-----------------------------------------------------UP (position)
‡D Crew and passenger oxygen----------------------------On, if required
‡E Descent--------------------------------------------------------Initiate, if required

The JTSB analysed:

It is highly probable that as a result of an investigation on the windshield, something like cracks, which the PIC found in the upper part of the left windshield, were arcing marks, and since cracks were not observed on the windshield. There was no decrease in strength regarding the left windshield. There was evidence of repairing the moisture seal, but it is highly probable that according to the maintenance record of the operator, repair work was carried out in accordance with the AMM. It is probable that the arcing marks were caused by the deterioration of the moisture seal and moisture penetration into inside of the left windshield, resulting in an arcing in the heater element; however, it could not be determined when this moisture penetration occurred.

(3) It is highly probable that based on CVR records, the PIC found something like cracks on the windshield and dealt with the situation in accordance with the check list as described in 2.7 (6).

(4) It is highly probable that as the PIC switched the cabin pressurization to manual mode and set the cabin altitude at the maximum climb rate according to the check list, the cabin altitude started to increase, resulting in abnormal decompression inside the aircraft.

(5) When flying at FL 340, the PIC commenced the check list, and the aircraft descended at a descent rate of about 3,000 ft/min, however, it is highly probable that it took more than 10 minutes for the aircraft to reach a flight altitude of 10,000 ft. On the other hand, the cabin altitude was approximately 5,700 ft when the PIC commenced the check list. It is highly probable that as the PIC switched to manual mode to set the cabin altitude at the maximum climb rate of 3,000}500 ft/min in accordance with the check list, the cabin altitude exceeded 10,000 ft within about two minutes.

(6) It is highly probable that based on DFDR records, the cabin altitude was exceeding 10,000 ft for 10 minutes 14 seconds between 17:58:46 and 18:09:00 while gCABIN ALTh (Warning) was being displayed.

(7) It is highly probable that in view of the fact that the oxygen masks in the cabin were automatically deployed and EICAS message gPASS OXY ONh (Caution) was displayed, the cabin altitude had exceeded 14,000}300 ft.

(8) Based on these factors, it is highly probable that as an arcing occurred in the left windshield during cruise, the PIC dealt with the situation in accordance with the check list to be followed at the time of occurrence of such problems, which caused the cabin altitude to rapidly climb, resulting in abnormal decompression inside the aircraft. The procedure of the checklist was required to uniformly set the cabin altitude at the maximum climb rate regardless of the degree of windows damage and the flight altitude. When flying at a high altitude like the aircraft, it is highly probable that it was inevitable that the cabin altitude reached the threshold for automatic deployment of the passenger oxygen masks.

(9) It is desirable that the Design and Manufacturer of the aircraft should review the check list in order to improve procedures which will prevent from occurring an abnormal decompression even when there occurs a similar incident.
Incident Facts

Date of incident
Oct 30, 2019

Classification
Incident

Cause
Cracked windshield

Airline
Ibex Airlines

Flight number
FW-16

Departure
Sendai, Japan

Destination
Fukuoka, Japan

Aircraft Registration
JA11RJ

Aircraft Type
Canadair CRJ-700

ICAO Type Designator
CRJ7

This article is published under license from Avherald.com. © of text by Avherald.com.
Article source

You can read 2 more free articles without a subscription.

Subscribe now and continue reading without any limits!

Subscribe now
Are you a subscriber? Login
Subscribe

Read unlimited articles and receive our daily update briefing. Gain better insights into what is happening in commercial aviation safety.

Compare our plans

Send tip

Support AeroInside by sending a small tip amount.

Send tip

Related articles

Newest articles

Subscribe today

Are you researching aviation incidents? Get access to AeroInside Insights, unlimited read access and receive the daily newsletter.

Pick your plan and subscribe

Partner

Blockaviation logo

A new way to document and demonstrate airworthiness compliance and aircraft value. Find out more.

ELITE Logo

ELITE Simulation Solutions is a leading global provider of Flight Simulation Training Devices, IFR training software as well as flight controls and related services. Find out more.

Blue Altitude Logo

Your regulation partner, specialists in aviation safety and compliance; providing training, auditing, and consultancy services. Find out more.

AeroInside Blog
Popular aircraft
Airbus A320
Boeing 737-800
Boeing 737-800 MAX
Popular airlines
American Airlines
United
Delta
Air Canada
Lufthansa
British Airways