WN278 - Incident: Southwest B737 at Burbank on Dec 6th 2018

A Southwest Airlines Boeing 737-700, registration N752SW performing flight WN-278 from Oakland,CA to Burbank,CA (USA) with 112 passengers and 5 crew, landed on Burbank's runway 08 (length 5800 feet/1765 meters) at 09:02L (17:02Z) but overran the end of the runway and came to a stop in the EMAS (engineered material arrestor system) past the end of the runway. There were no injuries, the aircraft sustained minor if any damage. The passenger disembarked via mobile stairs.

The airline reported the aircraft went into the EMAS at Burbank. All 112 passengers and 5 crew are unharmed and have disembarked via stairs.

On Jun 13th 2019 the NTSB reported they have opened an investigation into the occurrence rated an incident. The aircraft overran the end of runway 08 while landing in Burbank and came to a stop in the EMAS. There were no injuries, the aircraft sustained minor damage.

On Feb 11th 2021 the NTSB opened their investigtion docket into the occurrence and stated: "Probable cause and final report will be issued at a later date."

Within the docket the chairman of the flight data recorder specialist reported:

During the descent accelerations consistent with light to moderate turbulence were recorded below 7,000 ft. At about 8:58 PST the aircraft turned on to its final heading and captured the glideslope and localizer. The aircraft began to descend, maintaining the glideslope. Final flaps were selected at 8:59 PST and the airspeed decelerated to 133-136 knots, while groundspeed was at 144-145 knots. FMC calculated Vref speed was 126 knots. With final flaps selected, pitch varied from +3.3 deg to -1.7 deg and roll varied by +/-3.3 deg.

The aircraft touched down at 9:02:35 PST at an airspeed of 126 knots and a groundspeed of 149 knots. Winds at touchdown were reported by the FMC to be 20 knots at 285 degrees.

At touchdown, autobrakes, auto speedbrakes, and ground spoilers were all activated. Both thrust reversers transitioned and were fully deployed within 3 seconds of touchdown and engines spooled up with the thrust reversers deployed. Brake pressure reached its max of 3,000 psi in 7 seconds.

For the first 17 seconds following touchdown, the aircraft reached and maintained a deceleration rate of about 0.3 – 0.4 g. Groundspeed reached 44 knots in this time. For the next 5 seconds deceleration rate decreased to 0.15 to 0.2 g, slowing to a groundspeed of about 33 knots. Following this change the deceleration rate increased to its maximum of about 0.6 g until the aircraft stopped. The high rate was consistent with the aircraft decelerating in the EMAS.

The operational/human factors group chairman reported in his report, that the crew had never seen a stopping margin that low (245 feet at runway length 5802 feet), their Vref was computed at 126 KIAS and Vapp at 131 KIAS. ATC advised there had been a pilot report of loss of 15 knots of airspeed about 10 minutes prior to their arrival. Winds were reported from 260 degrees at 9 knots, about one minute prior to touchdown from 270 degrees at 11 knots. The crew reported their approach was smooth, no loss of airspeed was observed. The aircraft crossed the threshold at 54 feet and 137 KIAS. The crew reported in the landing flare at about 5 feet AGL rain intensity picked up and visibility reduced. Both crew believed they had touched down about 1300-1500 feet past the runway threshold, the NTSB performance study determined they touched down 2504 feet past the runway threshold.

The chairman wrote:

In his statement, the FO said that the speedbrakes and thrust reversers were deployed immediately on touchdown. He reported that the brake anti-skid system began to cycle, and the airplane did not slow appreciably at first. The captain stated that after touchdown, he used maximum reverse thrust and heard and felt chattering of the brakes through the brake pedals. He verified that the speedbrake handle was extended and “started blending in manual brakes after that.” He stated that with thrust reverse and autobrakes, the airplane did not feel like it was slowing. It then started to slow, but then deceleration decreased. As the airplane passed the intersection of runway 15/33 (about 3765 ft. from the runway 08 threshold) he became concerned about stopping. He stated that on a dry day, you could stow the thrust reversers and ease off the brakes at that point. He guessed that the airplane was at 70-80 knots at this point, faster than on a dry day. As they approached the final 1000-500 feet of the runway, the deceleration slowed markedly. He saw the large intersection where taxiway D1 intersected with the runway (about 5340 feet from the runway threshold) and thought he might be able to make a turn off the runway there, but as he tried to turn using left rudder and the tiller, he didn’t feel the airplane was responding. He felt the nosewheel was just skidding. He stated he then straightened out the nosewheel so they would not enter the EMAS with the nosewheel cocked sideways. The airplane entered the EMAS at a speed of about 10-15 knots and was quickly brought to a stop. The thrust reversers were still engaged upon entry.

The aircraft performance group reported that the landing performance calculation depended on the aircraft touching down between 1000 and 1500 feet past the runway threshold, a touchdown beyond 1500 feet would invalidate the performance calculation. The performance calculation, provided by the FMS, computed a landing roll of 3145 feet 1500 feet beyond the runway threshold and added a 15% safety reserve resulting in a landing distance required of 5,342 feet. Due to placement of glideslope antenna at 1215 feet past the runway threshold the computation reduced the actual landing distance available from 5802 to 5587 feet.

Related NOTAMs:
12/012 (A1008/18) - RWY 08/26 CLSD. 06 DEC 17:58 2018 UNTIL 07 DEC 07:00 2018. CREATED: 06 DEC 17:59 2018

12/014 (A1010/18) - RWY 26 RWY END ID LGT U/S. 06 DEC 20:54 2018 UNTIL 12 DEC 07:00 2018. CREATED: 06 DEC 20:54 2018

Metars:
KBUR 061806Z 01014G17KT 3SM +RA BR SCT022 BKN050 OVC070 08/08 A2992 RMK AO2 PRESFR P0006 T00830078=
KBUR 061753Z 29005KT 2 1/2SM +RA BR FEW020 BKN026 OVC048 08/07 A2996 RMK AO2 SLP139 AIRCRAFT MISHAP P0049 60166 T00830072 10100 20083 53035=
KBUR 061723Z 28012KT 1 1/4SM +RA BR FEW008 BKN016 OVC024 08/08 A2994 RMK AO2 AIRCRAFT MISHAP P0032 T00830078=
KBUR 061715Z 29008KT 1SM +RA BR FEW005 BKN013 OVC031 08/08 A2993 RMK AO2 AIRCRAFT MISHAP P0026 T00830078=
KBUR 061653Z 28011KT 1 1/2SM +RA BR FEW004 OVC013 08/08 A2991 RMK AO2 SLP122 P0033 T00830083=
KBUR 061641Z 26011KT 2 1/2SM RA BR FEW004 BKN013 OVC019 09/09 A2989 RMK AO2 P0023 T00890089=
KBUR 061553Z 29005KT 1 1/4SM +RA BR BKN011 BKN017 OVC047 09/09 A2986 RMK AO2 SLP106 P0021 T00940089=
KBUR 061547Z 29005KT 1 3/4SM +RA BR SCT011 BKN047 OVC060 09/09 A2986 RMK AO2 P0017=
KBUR 061453Z 32003KT 4SM RA BR FEW003 SCT026 OVC049 09/09 A2985 RMK AO2 SLP103 P0020 60063 T00940094 58002=
KBUR 061440Z 26005KT 4SM +RA BR FEW003 SCT026 OVC049 09/09 A2985 RMK AO2 P0016 T00940094=
KBUR 061353Z 31005KT 5SM RA BR FEW015 SCT025 OVC049 09/09 A2986 RMK AO2 SLP104 P0020 T00940094=
KBUR 061253Z 32007KT 3SM RA BR SCT010 OVC017 09/09 A2986 RMK AO2 SLP104 P0023 T00890089=

N752SW in the EMAS:

The nose gear stuck in the EMAS:

Map (Graphics: AVH/Google Earth):

Related Flight: WN278, Southwest Airlines News