30 Jul 2011, 9Y-PBM, 737-800, 29635/2326, FF 06 Jul 07, Caribbean Airlines; Georgetown, Guyana.
The approach was a normal RNAV approach, in rain, at night onto Runway 06 (2270m) at Cheddi Jagan International Airport (CJIA). The Captain was PF.
METAR SYCJ 300500Z 00000KT 9000 -SHRA FEW014CB BKN015 25/24 Q1009 CB-NE-ENE NOSIG=
Conditions on approach and over the runway were conducive to visual illusions. These conditions include the lack of approach lights, the featureless terrain, rain on the windscreen, the shallow approach path that was engendered by the glide slope angle of the beam projection of the PAPIs, and wet and sloping runway. Notwithstanding both flight crew members’ familiarity with conditions at the CJIA, they may have been affected by these visual illusions.
Visual refernces were obtained and the automatics disengaged. Upon reaching minimums the captain expressed doubt about the airplane’s approach profile and remarked that the airplane was slightly low on the glide-path. He then increased power to 65% N1 to correct the glide-path, this thrust was maintained for approximately the first 2000ft of runway. The captain did not reduce power during the flare and the copilot did not notice or call out the excess power during the flare.
As the flight continued over the runway, the captain indicated to the FO that the aircraft was not touching down. A go-around call was made by the Captain 16 seconds after crossing the threshold and acknowledged by the First Officer, however the aircraft touched down 3s later 4700 feet beyond the runway threshold, leaving just over 2700 feet of runway surface remaining.
After touch down, the captain did not apply maximum available reverse thrust or braking. The ground spoilers deployed at touchdown. The thrust reversers deployed as commanded by the crew to a position between idle and Detent 2 reverse thrust approximately three seconds after touchdown and 2000ft from the end of the runway. The Detent 2 reverse thrust position assumed in the QRH estimates was never commanded by the flight crew.
The final position of the aircraft was approximately 130ft from the end of the paved surface of RWY06 and 64ft off the extended runway center line. The aircraft suffered damage beyond economic repair. It broke into two sections in the vicinity of the first class bulkhead. Both engines were destroyed by the impact and FOD ingestion. There was no post-crash fire. There were no fatalities. One passenger suffered a broken leg which resulted in an amputation. Several other passengers and crew suffered minor injuries during the accident and evacuation.
The Guyana Civil Aviation Authority (GyCAA) published their final report in April 2019(!) significant extracts are given below:
*** Updated 18 Apr 2019 ***
On 30thJuly, 2011 Caribbean Airlines Flight BW523, a Boeing 737-800 aircraft, with 157 passengers and a crew of six, departed Piarco International Airport, (TTPP), Port of Spain Trinidad at 04:36hrs Universal Coordinated Time (UTC) on an instrument flight rules (IFR) flight plan on a scheduled flight to the Cheddi Jagan International Airport (CJIA), ICAO identifier: (SYCJ), Timehri, Guyana.
The aircraft landed at CJIA on runway 06 (RWY06) in the hours of darkness at 05:32hrs UTC, following an RNAV (GPS) approach. The reported aerodrome weather conditions were at 05:00hrs - wind calm, visibility 9km, light rain, few clouds 1400ft in cumulonimbus clouds, broken at 1500ft, QNH 1009hPA.
The aircraft touched down at approximately 4700 feet of the 7448 feet long runway, some 1700 feet beyond the runway touchdown zone. The runway was wet. The crew was unable to stop the aircraft on the remaining runway surface and it exited the end of the runway approximately 20ft left of the center line, breaking through a fence and coming to rest on the bottom of a 20ft high earth embankment.
The final position of the aircraft was approximately 130ft from the end of the paved surface of RWY06 and 64ft off the extended runway center line.
The aircraft suffered damage beyond economic repair. It broke into two sections in the vicinity of the first class bulkhead. Both engines were destroyed by the impact and foreign object debris (FOD) ingestion. There was no post-crash fire.
There were no fatalities. One passenger suffered a broken leg which resulted in an amputation. Several other passengers and crew suffered minor injuries during the accident and evacuation.
HISTORY OF THE FLIGHT
The flight originated in New York as BW 523, and made a passenger and fuel stop in Port-of-Spain, Trinidad where there was also a change of crew comprising two pilots and four flight attendants before proceeding to Georgetown, Guyana. The flight departed Piarco at 04:36UTC. The aircraft proceeded to Georgetown from Port of Spain at Flight Level (FL) 330, was given descent clearance and was cleared for an RNAV (GPS) approach to RWY 06, landing at 05:32 UTC. There were no reported anomalies in the en-route profile, although during the transition from cruise to approach to RWY 06 the aircraft deviated to avoid some thunderstorm cells north and east of the Airport. The reported visibility was 9,000m. Light rain was encountered during the approach. The pilot reported that after visual contact was made and after crossing the Final Approach Fix (FAF), he disengaged the auto pilot and configured the aircraft for landing. The Flight Data Recorder (FDR) indicated that the flight was normal until the aircraft was approaching the runway. Even before the aircraft was over the threshold, the captain commented that he was not landing here. As the flight continued over the runway, comments on the Cockpit Voice Recorder (CVR), revealed that the captain indicated to the First Officer (FO) that the aircraft was not touching down. A go-around call was made by the Captain and acknowledged by the First Officer, however three seconds elapsed and the aircraft subsequently touched down approximately 4700ft from the threshold of RWY06, leaving just over 2700 feet of runway surface remaining. Upon touchdown, brake pressure was gradually increased and maximum brake pressure of 3000psi was not achieved until the aircraft was 250ft from the end of the runway or 450ft from the end of the paved area. The ground spoilers were extended on touchdown. The thrust reversers were partially deployed after touchdown. The aircraft did not stop and overran the runway. It then assumed a downward trajectory followed by a loud impact.
DAMAGE TO AIRCRAFT
The aircraft suffered damage beyond economic repair. It was fractured at the first class bulkhead, with the cockpit portion resting at a 30° angle to the rest of the fuselage which was resting angled up at about a 10º angle from horizontal. The nose landing gear had collapsed underneath the cockpit and was pushed backwards into the fuselage where the avionics and electronics are typically housed. The fuselage, from the radar dome to about ten feet aft of the nose, was damaged and crumpled from impact. The thrust reverser doors were partially deployed on both engines which were severely damaged by impact and FOD ingestion.
The Captain was aged 52 and had 9,600hrsTT inc 5,000hrs on type.
The FO was aged 23 and had 1,400hrs TT inc 350hrs on type.
The Timehri (SYCJ) RNAV RWY06 Approach
The RNAV-GPS approach procedure aligns the aircraft on the RWY06 extended center line at position AKSIN, 11.2nm from the threshold at an altitude of 3000ft AMSL. The aircraft will continue the approach to cross the Final Approach Fix, position OLVIK, located 5.2nm from the threshold, at 1800ft. Thereafter the aircraft will make a continuous descent on a 3º slope to a Minimum Decision Altitude of 380ft AMSL. After this, approach and landing is completed by visual reference to the ground. If visual reference is not acquired when the aircraft reaches 380ft AMSL a MAP is carried out.
Caribbean Airlines Flight, BW523 was properly configured for landing at Georgetown, Guyana, early in the morning of July 30, 2011. There was no evidence of an aircraft malfunction, and the aircraft reached the runway threshold close to the QRH reference speed of Vref =149kt.
The aircraft touched down approximately 4700ft down the runway, leaving 2900ft of pavement to stop on.
The touchdown was 3700ft beyond the runway “aiming point” (or fixed distance marker) and 1700ft beyond the runway touchdown zone for landing operations. Assuming good braking on a wet runway with an average aircraft braking coefficient of 0.2, the aircraft could not have stopped before reaching the end of the runway using Auto-brakes 3.
The captain carried a power setting of 65% N1 for approximately the first 2000ft of runway. The high power setting explains the excessive float during the flare reported by the crew as well as the long touchdown.
Boeing was able to match the flight’s performance with their B737-800 simulation using the recorded FDR inputs. When the TLA’s were reduced to flight idle at 20ft AGL in the simulation, the aircraft touched down over 1700ft sooner than with the actual FDR TLA’s.
Boeing also used the simulation to show that it was possible to remain on the runway using Detent 2 reverse thrust.
The ground spoilers deployed at touchdown. The thrust reversers deployed as commanded by the crew to a position between idle and Detent 2 reverse thrust approximately three seconds after touchdown and 2000ft from the end of the runway. The Detent 2 reverse thrust position assumed in the QRH estimates was never commanded by the flight crew.
The analysis of the FDR shows that while on short final the aircraft was sinking below the desired glide-path and the crew increased power. The airplane regained the glide-path, but the pilot did not reduce power as the airplane entered the flare. The excess power resulted in the aeroplane floating beyond the intended touchdown point. Power was not reduced until the airplane was approximately 4000ft down the runway, about 6 seconds before touchdown. 3 seconds later the pilot called a go-around and advanced power, which contributed slightly to the float. However 3 seconds later the wheels touched down.
BW523 had approximately 2900ft of pavement to stop on when it touched down, 4700ft down the runway. Boeing’s landing distance estimates using a calculated aircraft braking coefficient as a function of groundspeed indicate that it was possible to stop the aircraft on the runway using either Detent 2 or maximum reverse thrust. However the ground spoilers were armed and as a result deployed at about the time of touchdown at 05:32:12 and the thrust reversers deployed (less than Détente 2 was commanded by the crew) 2 seconds later at 5:32:14 when the aeroplane was 2000ft from the end of the runway. Further the crew applied gradual brake pressure starting at touch down, maximum brake pressure of 3000psi was not achieved until the aircraft was 250ft from the end of the runway.
Because the aircraft touched down so far down the runway and the crew did not use all of the available deceleration devices, it was not stopped on the paved surface and exited the prepared surface of the runway and impacted a berm resulting in substantial damage to the airframe.
The probable cause of the accident was that the aircraft touched down approximately 4700 feet beyond the runway threshold, some 2700 feet from the end of the runway, as a result of the Captain maintaining excess power during the flare, and upon touching down, failure to utilize the aircraft’s full deceleration capability, resulted in the aircraft overrunning the remaining runway and fracturing the fuselage.
The Flight Crew’s indecision as to the execution of a go-around, failure to execute a go-around after the aircraft floated some distance down the runway and their diminished situational awareness contributed to the accident.
Actions by CAL
Actions by TTCAA
Actions by SYCJ
Action by GCAA
Consider need for a meteorological officer to be stationed at a strategic location on the field to provide local weather information.
The full final report can be read here. https://gcaa-gy.org/pdf/CAL-Accident-Report-Guyana.pdf