Jordan B734 at Tombouctou on May 5th 2017, overran runway on landing

Last Update: May 17, 2018 / 16:48:58 GMT/Zulu time

Bookmark this article
Incident Facts

Date of incident
May 5, 2017

Classification
Report

Flight number
R5-7843

Departure
Bamako, Mali

Destination
Tombouctou, Mali

Aircraft Registration
JY-JAP

Aircraft Type
Boeing 737-400

ICAO Type Designator
B734

A Jordan Aviation Boeing 737-400, registration JY-JAP performing flight R5-7843 from Bamako to Tombouctou (Mali) with 90 passengers and 11 crew, was on approach to Tombouctou's runway 07, tower reported winds from 250 degrees at 4 knots in 5km visibility and dry runway. About 5nm from the runway threshold the first officer (30, ATPL, 3,300 hours on type), pilot monitoring, stated EHSI and FMC showed a tail wind component of 16 knots in excess of the operating limits of the aircraft. The captain (63, ATPL, 9,000 hours on type) acknowledged and continued the approach. The aircraft touched down 350 meters past the runway threshold, just past the touch down zone markings, at 141 KIAS, 15 knots above computed Vapp for flaps 30 being used, and 16 knots tailwind. After touchdown the spoilers were manually commanded into the ground up position, the thrust reversers were deployed with the left hand thrust reverser lagging behind by about 3 seconds creating a small drift of about 2 degrees. After the nose wheels touched down the captain applied increased manual brakes pressure and maximum reverse thrust as he perceived the deceleration as insufficient. The aircraft travelled down the 2170 meters long runway, went beyond the runway end near the taxiway edge at the runway end and came to rest past the runway end and to the right of the runway right hand edge on soft ground. There was no fire, the captain therefore did not initiate an evacuation. The passengers disembarked onto soft ground via mobile stairs through the right forward door. No injuries occurred, the aircraft sustained damage to all fan blades of the left hand engine (CFM56).

Jordan's Civil Aviation Regulatory Commission (JCARC) released their final report concluding the probable causes of the serious incident were:

The cause of the occurrence was a high energy unstabilized approach followed by a landing with an excessive speed with higher than operational limit tailwind component, in addition to non-efficient usage of the wheel brakes.

A contributing factor to the incident was a combination of deficiencies involving aspects of crew resource management and human factors in which involved the captain leadership, team work and F/O assertiveness.

The JCARC analysed: "The FDR Analysis shows that the aircraft approach was unstable as the vertical speed and tail wind component were showing higher than normal readouts and this continued till the point of touchdown."

The JCARC continued analysis: "Jordan aviation has a policy on unstabilized approaches that is based on internationally accepted standards and on the recommendations issued by Boeing, the manufacturer of the aircraft." and stated: "Any significant deviation from planned flight path, airspeed, or descent rate should be announced. The decision to execute a go-around is not an indication of poor performance."

The JCARC analysed:

In understanding why the flight crew continued the approach and did not consider a go-around, it is important to know that the captain of the flight had experienced some delays in Tombouctou airport in previous flights which according to his statement comes as a result of services non availability in that airport, so; his plan was to continue the approach without affecting the fuel quantity. According to his statement; asking for extra fuel would result in an extra ground time as they have to request that fuel from another air base near to TOM airport and this delay may extend to 2 hours. This would in turn affect the schedule, flight duty time and customer satisfaction.

Flight crews can be subject to a plan continuation bias. Without salient triggers, they will continue with their original plan (that is, to carry out the landing). In this occurrence and according to his understanding there was nothing particularly significant to cause the captain to re-evaluate the original plan of action. Therefore, the flight crew’s recognition that the aircraft was unstable at that point during the approach would have been affected because of plan continuation bias and reliance on the captain skills to land the aircraft uneventfully.

According to his statement, the First officer who was the pilot monitoring on the occurrence flight said that he did not show an assertive action when he realized that the approach was unstabilized because he had previous experience in which the captain of the occurrence flight continued an unstable approaches to landing and he added that in some cases when he was flying the aircraft in some of these flights the captain was taking the controls over whenever the approach was found unstable.

The JCARC analysed:

At 08:35:45 the aircraft passed runway 07 threshold at 48 ft AAL, the speed was still higher than the recommended Vapp+10, the indicated airspeed was recording 157 kts and tailwind component was 16 kts with a ground speed of 182 kts. The pitch was recording 2.8 deg while the vertical speed was showing a value of 608 ft/min.

At 08:35:47 the aircraft was at 25 ft AAL and the pilot flying started the flare by pushing the control column to produce a 4.9 deg pitch angle, this slowed the rate of descent to 466 ft/min. the engine thrust was decreased by retarding the thrust levers to 35% N1. The flare continued for 7 seconds at which the vertical speed was bled off to 233 ft/min and the aircraft touched the ground at a distance of approximately 350 m from the runway threshold. However; the indicated airspeed was higher than the recommended approach speed at touchdown and with tailwind recording 16 kts.

At 08:35:53 the aircraft touched down the ground with an indicated airspeed of 148 kts and a ground speed of 173 kts this increase in ground speed is due to the tailwind factor that affected the aircraft during its approach and landing phases. The vertical speed at touchdown was bled off to 233 ft/min which is below the limit of hard landing (360 ft/min) and the gravitational vertical acceleration recorded a maximum value of 1.28 g, which indicates that the landing was not hard. The thrust reversers were deployed immediately at touchdown. The FDR data shows that the left engine thrust reverser lagged for 4 seconds from the right engine, resulting in a drift angle of 2 degrees to the right. At 08:35:56 the nose landing gear touched the ground and after 2 seconds at 08:53:58 the thrust reversers were set to maximum thrust with 95 – 97% N1untill the aircraft came to rest on the unpaved area at which they were stowed to close position.

The pilot flying applied a left brake pedal pressure in an attempt to maintain the aircraft in the center line and to compensate this 2 deg of drift. This left brake application lasted to 6 seconds after touchdown.
The brake pressure on the right side was evidenced 5 seconds after touchdown with a value reaching to 3400 PSI.

At 08:36:00 both brake pedals were released momentarily, the brake pedal release lasted to 2 seconds for left and 4 seconds for right brakes. The right brake pressure was not sufficient to provide proper braking performance in which it reached 2000 PSI.

At 08:36:10 both pedal were depressed to the maximum pressure and were showing a brake pressure of 3200 – 3300 PSI.

At 08:36:19 the brake pedals were released again and the ground speed was showing 60 kts, the pilot flying turned the nose wheel steering toward the taxiway entrance which is perpendicular to the runway. The total distance travelled on the runway from the point of touchdown to the point at which the pilot flying used the hand wheel steering to turn the aircraft was 4860 ft (the remaining runway length is ((7118-1148) – (4860) = 1110 ft)).

According to the above performance calculation, it is believed that if the crew kept a continuous maximum brake pressure on the brake pedals, the aircraft would stop on the available remaining length of the runway. Baring in mind that the runway is provided with an extra 60 meters as a stopway at both ends of the runway.

...

During the first 10 seconds of the landing run, while the aircraft forward speed was higher than normal due to the high rate of descent and tailwind component effect, the braking efficiency varied between low to medium. It then increased during the following seconds of the landing run reaching the highest value at the end of the run just before heading deviation.

The high brake energy released from the braking action resulted in tires prints on the runway just prior to aircraft turn towards the taxiway track.

With respect to Cockpit Resource Management CRM the JCARC analysed:

THE LEADERSHIP OF THE CAPTAIN AND TEAM WORK

The interview held with the operating crew of the occurrence flight revealed that the captain who was pilot flying made every decision and at no time did he ask the F/O his opinion. He decided to continue the approach in spite it was unstable. He eventually decided to land the aircraft using the manual brakes not according to the SOPs and without an assessment to the landing runway. Finally he decided to vacate the runway at higher than allowable speed to the taxiway in spite of the F/O calls not to do that action.

THE F/O LACK OF ASSERTIVENESS

When the captain decided to continue the approach, The F/O did not exhibit the necessary assertiveness to check with the tower for an update to the weather report after he was aware of the deviation in tailwind values that were exceeding the limitations. The F/O lack of assertiveness was also evident in when he did not tell the captain that the rate of descent was going higher than the known stabilized approach limits. The F/O lack of assertiveness to tell the captain that he did not agree with what he was doing is undoubtedly a contributing factor to the development of the incident.
Incident Facts

Date of incident
May 5, 2017

Classification
Report

Flight number
R5-7843

Departure
Bamako, Mali

Destination
Tombouctou, Mali

Aircraft Registration
JY-JAP

Aircraft Type
Boeing 737-400

ICAO Type Designator
B734

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!

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.

Send tip

Support AeroInside by sending a small tip amount.

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