N552JB

HISTORY OF FLIGHT

On June 17, 2012, about 1608 Pacific daylight time (PDT), JetBlue Airways flight 194, an Airbus A320-232, N552JB, experienced a loss of two of its three hydraulic systems after departure from Las Vegas McCarran International Airport (LAS), Las Vegas, Nevada. After restoring one of the lost hydraulic systems and flying a holding pattern to burn off fuel, the flight crew returned to land at LAS and the airplane was towed to the gate. The flight was operating under the provisions of Title 14 Code of Federal Regulations (CFR) Part 121 as a regularly scheduled passenger flight to John F. Kennedy International Airport (JFK), Jamaica, New York. Visual meteorological conditions prevailed at the time of the incident.

The incident flight was originally scheduled to depart LAS for JFK at 1500 PDT. Due to a delay on the inbound flight, which was operated by a different crew, the flight was rescheduled to depart LAS at 1545 PDT. The flight took off at 1606 PDT at a weight of 168,724 pounds, which was about 1,000 pounds below the maximum allowable takeoff weight.

During landing gear retraction after takeoff, the Green hydraulic system lost pressure and the flight warning computer detected a flight control flaps system fault followed by a reservoir overheat condition for the Yellow hydraulic system 2 minutes later. During the initial climb, a flight attendant called the cockpit and reported a loud screeching sound, which the captain perceived to be the hydraulic power transfer unit (PTU) working in "overdrive." Normal inhibition of alerts and warnings from the flight warning computer prevented notification to the flight crew until the airplane had climbed out of 1,500 above ground level; after which, the pilots experienced a period of high workload as they received multiple aural and visual warnings on the flight deck after climbing through about 1,760 feet above ground level.

The captain, who was the pilot flying, transferred airplane control to the first officer and began to accomplish the abnormal procedures that were displayed on the electronic centralized aircraft monitor (ECAM). Accomplishing the procedures included turning off the Green and Yellow hydraulic systems' engine-driven pumps and the PTU. This action resulted in Yellow hydraulic system low pressure (in addition to the already lost Green hydraulic pressure), the airplane's reversion to alternate law in which flight envelope protections are reduced, and autopilot and autothrust disconnection. The crew attempted to raise the flaps from position 1 (the takeoff position) to 0, but the flaps remained at position 1.

At this point, of the airplane's three hydraulic systems, only the Blue system was providing useable pressure. The crew coordinated with air traffic control to enter a holding pattern at 12,000 feet to accomplish checklists and communicate with company maintenance and dispatch. During this time, the Yellow hydraulic system was recovered and the flight operated with both the Blue and the Yellow hydraulic systems for the remainder of the flight. The captain stated during post incident interviews that there was some uncertainty regarding the position of the flaps, as the flap position indicator on the flight deck appeared to be locked between 0 and 1.

The captain used the procedures in the quick reference handbook to calculate landing distance performance and initially calculated a required landing distance of over 11,000 feet considering two hydraulic systems to be inoperative. After the Yellow system was recovered, the captain calculated a revised landing distance of about 8,500 feet.

The flaps system fault required a higher-than-normal landing speed, and the Green hydraulic system malfunction resulted in loss of normal braking, loss of nosewheel steering on the ground, and loss of the ability to retract the landing gear once extended. Due to the system malfunctions and the inability to raise the landing gear in the event of a go-around, the flight crew decided to remain in the holding pattern to burn fuel and reduce aircraft weight below the maximum landing weight of 142,200 pounds. The flight landed at LAS at 1937 PDT at a weight of 140,640 pounds, and the airplane was towed to the gate where the passengers and crew deplaned via a jetway to the airport terminal.

INJURIES TO PERSONS

There were no injuries to the 149 passengers and 5 crewmembers (2 pilots and 3 flight attendants) on board.

DAMAGE TO AIRPLANE

The airplane sustained minor damage to the hydraulic system.

PERSONNEL INFORMATION

The captain, age 36, was hired by JetBlue in March 2006 and upgraded to captain on the A320 in July 2011. At the time of the incident, he was based in New York.

According to company records, the captain had logged 9,187 hours total flight time, including 4,687 hours in the A320 with 510 hours as pilot-in-command on the A320. FAA records indicated no history of previous accidents or incidents involving the captain.

The captain held a valid Federal Aviation Administration (FAA) airline transport pilot (ATP) certificate with type ratings for the A320, CL-65, ERJ-170, and ERJ-190 and a current FAA first-class medical certificate with a limitation that he must wear corrective lenses. Training and proficiency checks were current and there was no record of failures during company training events.

Company records indicated that the captain had logged 5 hours flight time in the 24 hours before the incident and had logged 16, 29, and 91 hours in the previous 7, 30, and 90 days, respectively.

The captain had been on duty during the 3 days preceding the incident. He reported for duty at 1410 PDT on the day of the incident and, although he could not recall at what time he had gone to sleep each of the three previous nights, stated in post incident interviews that he had not felt tired.

The first officer, age 54, was hired by JetBlue on the A320 in March 2006 and was based in New York.

Company records indicated the first officer had logged 13,700 hours total flight time, including 4,800 hours as second-in-command in the A320. He had also logged 2,500 hours as pilot-in-command. FAA records indicated no history of previous accidents or incidents involving the first officer.

The first officer held a valid ATP certificate with type ratings for the A320, B707, B720, CL-65, ERJ-170, and ERJ-190 and a current FAA first-class medical certificate with a limitation indicating he must wear corrective lenses. According to company records, the first officer had logged 5 hours flight time in the 24 hours before the incident and had logged 16, 85, and 240 hours in the previous 7, 30, and 90 days respectively.

The first officer had been on duty, flying with the incident captain, for the 2 days preceding the incident. He could not recall his sleep and wake times in the 3 days before the incident but stated that he usually slept for 7 to 8 hours each night.

The incident occurred on the first leg of the last day of a 3-day trip. The incident flight was the only flight leg planned for the pilots that day.

AIRCRAFT INFORMATION

The incident airplane, manufacturer serial number 1861, is an Airbus A320-232 equipped with two International Aero Engines V2500 turbofan engines. The airplane had logged about 38,705 hours total time on the airframe, and the most recent inspection was conducted on June 13, 2012, as part of the operator's continuous airworthiness maintenance program. Company records indicated that the airplane was operated on the incident flight with a deferred maintenance item. The slat/flap control system 2 flap channel was inoperative and deferred in accordance with the FAA-approved minimum equipment list.

Hydraulic System

The aircraft has three main hydraulic systems identified as the Green, Blue, and Yellow systems. The three systems are not hydraulically connected but together supply hydraulic power at 3,000 pounds per square in (psi) to the main power users; flight controls, thrust reversers, cargo doors, landing gear, brakes, and nosewheel steering. Reservoirs for each system are pressurized by bleed air from the pneumatic system to ensure a sufficient supply of hydraulic fluid to the pumps.

Each system is pressurized by one main pump: the Green system by an engine-driven pump connected to the left engine, the Yellow system by an engine-driven pump connected to the right engine, and the Blue system by an electric pump that operates when at least one engine is running.

Post incident examination of the airplane found a leak in the right main landing gear door retraction flexible hydraulic line in the Green hydraulic system.

Power Transfer Unit

The aircraft has a PTU to transfer power between the Green and Yellow hydraulic systems. The connection between the two systems is mechanical and no fluid is transferred between them. The PTU is armed when the hydraulic systems are pressurized and automatically operates when there is a pressure difference of 500 psi or more between the Green and Yellow systems.

Flap/Slat System

There are two flap and five slat surfaces on each wing. These surfaces are electrically controlled, hydraulically actuated, and receive control signals transmitted from two slat flap control computers (SFCC), which each contain one slat channel and one flap channel. The slats are powered by both the Green and Blue hydraulic systems while the flaps are powered by the Green and Yellow hydraulic systems.

In the event of a failure of both SFCC channels or failure of both the Green and the Yellow hydraulic systems, the flaps will be locked in the position attained at time of failure.

Flap system 1 was controlled by SFCC channel 1 and powered by the Green hydraulic system. Flap system 2 was controlled by SFCC channel 2 and powered by the Yellow hydraulic system. The incident flight was dispatched with the SFCC flap channel 2 inoperative in accordance with FAA-approved procedures and was therefore operating with flap cont...