Category Archives: NTSB

NTSB issues recommendations to the FAA for the evaluation and certification of lithium-ion batteries on Boeing 787s

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The National Transportation Safety Board (NTSB) (Washington) has issued a series of recommendations related to the evaluation and certification of lithium-ion batteries for use in aircraft systems, as well as the certification of new technology.

The five safety recommendations, all addressed to the Federal Aviation Administration (FAA) (Washington), are derived from the NTSB’s ongoing investigation of the January 7, 2013, fire event that occurred in a lithium-ion battery on a Boeing 787 that was parked at Boston Logan Airport.

Investigators found that the battery involved in the Boston 787 fire event showed evidence not just of an internal thermal runaway but that “unintended electrical interactions occurred among the cells, the battery case, and the electrical interfaces between the battery and the airplane.”

The 12-page safety recommendation letter said that the processes used in 2006 to support the certification of the lithium-ion battery designed for the 787 were inadequate, in part, because there is no standardized thermal runaway test that’s conducted in the environment and conditions that would most accurately reflect how the battery would perform when installed and operated on an in-service airplane.

Further, the NTSB said that because there is no such standardized thermal runaway test, lithium-ion battery designs on airplanes currently in service might not have adequately accounted for the hazards associated with internal short circuiting.

In its examination of the challenges associated with introducing newer technologies into already complex aircraft systems, the NTSB said that including subject matter experts outside of the aviation industry “could further strengthen the aircraft certification process” by ensuring that both the FAA and the aircraft manufacturer have access to the most current research and information related to the developing technology.

To address all of these issues, the NTSB asked the FAA to do the following:

1. Develop an aircraft-level thermal runaway test to demonstrate safety performance in the presence of an internal short circuit failure
2. Require the above test as part of certification of future aircraft designs
3. Re-evaluate internal short circuit risk for lithium-ion batteries now in-service
4. Develop guidance for thermal runaway test methods
5. Include a panel of independent expert consultants early in the certification process for new technologies installed on aircraft

“The history of commercial aviation is one in which emerging technologies have played a key role in enhancing flight safety,” said NTSB Acting Chairman Christopher A. Hart. “This is why it’s crucial that the process by which these technologies are evaluated and certified is as robust and thorough as possible. These recommendations will take us further in that direction.”

The final report on the January 2013 Boston 787 battery fire investigation is estimated to be completed in the fall.

Read the full report: CLICK HERE

Read about the original Boston JAL Boeing 787 incident: CLICK HERE

 

NTSB Chairman Hersman’s briefing on the Asiana Airlines Boeing 777 crash at San Francisco

National Transportation Safety Board’s Chairperson Hersman briefs the media at yesterday’s hearing in Washington on the Asiana Airlines Boeing 777 crash. The main theme of the investigation is centered around the overuse of automation.

Read the analysis by Reuters: CLICK HERE

NTSB: The captain took over Southwest flight 345 seconds before its hard landing at New York LaGuardia Airport on July 22

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The National Transportation Safety Board (NTSB) (Washington) has issued this statement regarding the investigation of the hard landing of Southwest Airlines (Dallas) flight 345 at New York (LaGuardia) on July 22, 2013:

In its continuing investigation of the July 22 accident in which Southwest Airlines flight 345, a Boeing 737-700, landed hard at New York’s LaGuardia Airport (LGA), the National Transportation Safety Board has developed the following factual information:

  • The captain has been with Southwest for almost 13 years and has been a captain for six of those years. The captain has over 12,000 total flight hours, over 7,000 of which are as pilot-in-command. In 737s, the captain has over 7,900 hours, with more than 2,600 as the pilot-in-command.
  • The first officer has been with Southwest for about 18 months. The pilot has about 5,200 total flight hours, with 4,000 of those as pilot-in-command. In 737s, the first officer has about 1,100 hours, none of which are as the pilot-in-command.
  • This was the first trip the flight crew had flown together and it was the second leg of the trip. The first officer had previous operational experience at LGA, including six flights in 2013. The captain reported having flown into LGA twice, including the accident flight, serving as the pilot monitoring for both flights.
  • The en route phase of the flight, which originated in Nashville, was characterized by the flight crew as routine. On approach into LGA, the first officer was the pilot flying and the captain was the pilot monitoring. SWA 345 was cleared for the ILS Runway 4 approach.
  • The weather in the New York area caused the accident flight to enter a holding pattern for about 15 minutes. The crew reported that they saw the airport from about 5-10 miles out and that the airplane was on speed, course and glideslope down to about 200-400 feet.
  • The crew reported that below 1,000 feet, the tailwind was about 11 knots. They also reported that the wind on the runway was a headwind of about 11 knots.
  • SWA 345 proceeded on the approach when at a point below 400 feet, there was an exchange of control of the airplane and the captain became the flying pilot and made the landing.
  • The jetliner touched down on the runway nose first followed by the collapse of the nose gear; the airplane was substantially damaged.

At this point in the investigation, no mechanical anomalies or malfunctions have been found. A preliminary examination of the nose gear indicated that it failed due to stress overload.

Investigators have collected five videos showing various aspects of the crash landing. The team will be analyzing these recordings in the coming months.

Parties to the investigation are the Federal Aviation Administration, Boeing Commercial Airplanes, Southwest Airlines, and the Southwest Airlines Pilots Association.

This is a factual update only and no interviews are being conducted.

Southwest Airlines’ landed nose wheel first at LaGuardia Airport

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Southwest Airlines‘ (Dallas) Boeing 737-700 involved in the crash landing at New York’s LaGuardia Airport on July 22 landed with the nose wheel striking the runway first (the aircraft did not flare fro landing) according to the NTSB. The NTSB issued this statement:

The National Transportation Safety Board released factual information from the July 22 accident involving a Southwest Airlines Boeing 737-700 landing at New York’s LaGuardia Airport. The airplane’s front landing gear collapsed on landing.

  • Evidence from video and other sources is consistent with the nose-gear making contact with the runway before the main landing gear.
  • The flight data recorder on the airplane recorded 1,000 parameters and contained approximately 27 hours of recorded data, including the entire flight from Nashville to New York.
  • The cockpit voice recorder contains a two-hour recording of excellent quality that captures the entire flight from Nashville to New York and the accident landing sequence.
  • Flaps were set from 30 to 40 degrees about 56 seconds prior to touchdown.
  • Altitude was about 32 feet, airspeed was about 134 knots, and pitch attitude was about 2 degrees nose-up approximately 4 seconds prior touchdown.
  • At touchdown, the airspeed was approximately 133 knots and the aircraft was pitched down approximately 3 degrees.
  • After touchdown, the aircraft came to a stop within approximately 19 seconds.
  • A cockpit voice recorder group will convene at NTSB laboratories in Washington to transcribe the relevant portion of the accident flight.

Southwest Airlines: AG Slide Show

Asiana Airlines’ pilot sees a bright light on the final approach

National Transportation Safety Board (NTSB) (Washington) has conducted its final press conference in San Francisco. The landing Asiana Airlines pilot reported a bright light source on his final approach (reflection of the sun on the water?). The pilot looked away and did not think it blinded him. The other pilot did not report any source of light. Here is the briefing from yesterday afternoon (July 11). The final accident report will probably take a year or longer before it is issued. If there are any recommendations, the NTSB will issue those recommendations sooner to the Federal Aviation Administration (FAA).

Meanwhile the remains of the Boeing 777 are slowly being removed.

The latest (July 10) NTSB briefing on the Asiana Airlines crash

The National Transportation Safety Board (NTSB) issued this briefing on the Asiana Airlines crash at San Francisco late yesterday (July 10). The briefing includes new information on the pilots.

NTSB to conduct teardown examinations on Boeing 787 batteries cells with CT scans

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The National Transport Safety Board (NTSB) (Washington), which is still investing the Boeing 787 battery fire at Boston, is seeking help in conducting teardown examinations of Boeing 787 battery cells. The NTSB is asking for help with the CT scans.

The NTSB issued this statement:

The NTSB is planning to conduct teardown examinations as soon as possible of several aircraft batteries similar to one involved in an aircraft incident. This urgent requirement is in support of accident investigation DCA13IA037 that occurred in Boston, MA. To facilitate those examinations, CT scans of these batteries and their subcomponents are required to non-destructively determine as much information as possible about those components. In addition, batteries and battery cells of the same type which have been subjected to known test conditions will also be scanned. These scans will be conducted both before and after the test conditions are applied. Since these batteries are of the lithium ion type and have substantial shipping restrictions (including a requirement for ground shipping only using specially qualified hazardous materials shippers which would cause a delay of several days to accommodate), these scans need to be conducted at a location close to Washington, D.C. to allow the NTSB to transport the battery to the contractor and thereby avoid shipping and other logistical complications. They must also be completed within the shortest timeframe possible to provide the fastest possible receipt of this information to avoid potential future accidents involving this type of aircraft battery. Since the FAA has recently approved a plan intended to result in the Boeing 787 being approved for a return to service, the information from these tests (and the CT scans required to support these tests) is needed as soon as possible. A scan report that documents items such as the x-ray source power used, x-ray focal spot size, detector used, integration time, number of views, image pixel size, slice thickness, total length scanned, number of slices, etc. is due no later than 10 days after the end of the scanning activity. The NTSB has a requirement for CT scanning services to begin on May 6, 2013. Therefore, this requirement is urgent.

 

The NTSB has a requirement for CT scans of eight (8) Boeing 787 batteries cells. In addition, the NTSB has a requirement for additional scanning work for up to 40 additional battery cells or their equivalent scanning effort to be used as needed at the discretion of the NTSB. The scanning work for the “up to 40 additional battery cells” will be conducted in two installments. The cells will first be scanned in a “before testing” configuration, and then scanned again after testing has been completed with the cells. Finally, the NTSB requires at least 2 digital radiographs per component (90 degrees apart).

Read the full report: CLICK HERE

NTSB is making progress on the JAL Boeing 787 battery fire investigation

The National Transportation Safety Board (Washington) has issued this new interim report on the Boeing 787-8 fire at Boston:

The National Transportation Safety Board has released the seventh update on its investigation into the January 7 fire aboard a Japan Airlines Boeing 787 at Logan International Airport in Boston.

The auxiliary power unit battery, manufactured by GS Yuasa, was the original battery delivered with the airplane on December 20, 2012. It is comprised of eight individual cells. All eight cells came from the same manufacturing lot in July 2012. The battery was assembled in September 2012 and installed on the aircraft on October 15, 2012. It was first charged on October 19, 2012.

Examination and testing of an exemplar battery got underway earlier this week at the Carderock Division of the Naval Surface Warfare Center laboratories in West Bethesda, MD. The tests consisted of electrical measurements, mass measurements, and infrared thermal imaging of each cell, with no anomalies noted. The cells are currently undergoing CT scanning to examine their internal condition. In addition, on Thursday, a battery expert from the Department of Energy joined the investigative team to lend his expertise to the ongoing testing and validation work.

In Seattle, NTSB investigators and Boeing engineers examine the type of lithium ion battery used on the Boeing 787 to start the auxiliary power unit and to provide backup power for flight critical systems.
In Seattle, NTSB investigators and Boeing engineers examine the type of lithium ion battery used on the Boeing 787 to start the auxillary power unit and to provide backup power for flight critical systems.

NTSB investigators were made aware of reports of prior battery replacements on aircraft in the 787 fleet, early in the investigation. As reported Tuesday, Boeing, a party to the investigation, is providing pertinent fleet information which investigators will review to determine if there is any relevance to the JAL investigation.

An investigative group continued to interpret data from the two digital flight data recorders on the aircraft, and is examining recorded signals to determine if they might yield additional information about the performance of the battery and the operation of the charging system.

Next week, the NTSB battery testing team will initiate a non-invasive “soft short” test of all cells of the exemplar battery. This test will reveal the presence of any high resistance, small or “soft” shorts within a cell. Also, an NTSB investigator will travel to France with the battery contactor from the JAL event battery, for examination at the manufacturer. The battery contactor connects a wiring bundle from the airplane to the battery.

Investigators are continuing their work in Washington and Japan and the team in Seattle continues to observe the FAA-led review of the certification process for the 787 battery system. The flow of information from these observations helps to inform NTSB investigative activity in the US and around the world.

Additional information on the NTSB’s investigation of the Japan Airlines B-787 battery fire in Boston is available at http://go.usa.gov/4K4J.

The NTSB will provide another factual update as developments warrant.

Excess voltage of the 787 batteries is ruled out as the cause of the Boston JAL fire, NTSB now looking at the APU

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The National Transportation Safety Board (NTSB) (Washington) has ruled out excess voltage as the cause of a battery fire this month on a Boeing 787 operated by Japan Airlines (Tokyo) according to Reuters (see reports below) and said they were expanding the probe to look at the battery’s charger and the jet’s auxiliary power unit.

According to the report, investigators will convene in Tucson, Arizona today to test and examine the charger for the battery, and download non-volatile memory from the APU controller, with similar tests planned at the Phoenix facility where the APUs are built.

Read the full report: CLICK HERE

On January 14 the NTSB issued this preliminary report:

The National Transportation Safety Board today released a second update on its investigation into the Jan. 7 fire aboard a Japan Airlines Boeing 787 at Logan International Airport in Boston.

The lithium-ion battery that powered the auxiliary power unit on the airplane was removed and transported back to the NTSB Materials Laboratory in Washington on Jan. 10. The battery is currently being examined by NTSB investigators, who plan to disassemble it this week.

Click for Larger Image
NTSB photos of the burned auxiliary power unit battery from a JAL Boeing 787 that caught fire on Jan. 7 at Boston’s Logan International Airport. The dimensions of the battery are 19×13.2×10.2 inches and it weighs approximately 63 pounds (new).

 

In advance of that work, under the direction of the NTSB, radiographic examinations of the incident battery and an exemplar battery were conducted this past weekend at an independent test facility. The digital radiographs and computed tomography scans generated from this examination allowed the team to document the internal condition of the battery prior to disassembling it.

In addition, investigators took possession of burned wire bundles, the APU battery charger, and several memory modules. The maintenance and APU controller memory modules will be downloaded to obtain any available data. Investigators also documented the entire aft electronics bay including the APU battery and the nearby affected structure where components and wire bundles were located. The airplane was released back to Japan Airlines on Jan. 10.

The airplane’s two combined flight data recorder and cockpit voice recorder units were transported to NTSB headquarters and have been successfully downloaded. The information is currently being analyzed by the investigative team.

The airport emergency response group documented the airport rescue and firefighting efforts to extinguish the fire, which included interviews with first responders. Fire and rescue personnel were able to contain the fire using a clean agent (Halotron), however, they reported experiencing difficulty accessing the battery for removal during extinguishing efforts. All fire and rescue personnel responding to the incident had previously received aircraft familiarization training on the Boeing 787. In accordance with international investigative treaties, the Japan Transport Safety Board and French Bureau d’Enquêtes et d’Analyses pour la sécurité de l’aviation civile have appointed accredited representatives to the investigation. The NTSB-led investigative team is comprised of subject matter groups in the areas of airplane systems, fire, airport emergency response, and data recorders and includes experts from the Federal Aviation Administration, The Boeing Company, US Naval Surface Warfare Center’s Carderock Division, Japan Airlines (aircraft operator), GS Yuasa (battery manufacturer), and Thales Avionics Electrical Systems (APU battery/charger system).

On January 20 the NTSB issued this on-going report:

The National Transportation Safety Board today released a third update on its investigation into the Jan. 7 fire aboard a Japan Airlines Boeing 787 at Logan International Airport in Boston.

The lithium-ion battery that powered the auxiliary power unit has been examined in the NTSB Materials Laboratory in Washington. The battery was x-rayed and CT scans were generated of the assembled battery. The investigative team has disassembled the APU battery into its eight individual cells for detailed examination and documentation. Three of the cells were selected for more detailed radiographic examination to view the interior of the cells prior to their disassembly. These cells are in the process now of being disassembled and the cell’s internal components are being examined and documented.

Investigators have also examined several other components removed from the airplane, including wire bundles and battery management circuit boards. The team has developed test plans for the various components removed from the aircraft, including the battery management unit (for the APU battery), the APU controller, the battery charger and the start power unit. On Tuesday, the group will convene in Arizona to test and examine the battery charger and download nonvolatile memory from the APU controller. Several other components have been sent for download or examination to Boeing’s facility in Seattle and manufacturer’s facilities in Japan.

Finally, examination of the flight recorder data from the JAL B-787 airplane indicate that the APU battery did not exceed its designed voltage of 32 volts.

In accordance with international investigative treaties, the Japan Transport Safety Board and French Bureau d’Enquêtes et d’Analyses pour la sécurité de l’aviation civile have appointed accredited representatives to this investigation. Similarly, the NTSB has assigned an accredited representative to assist with the JTSB’s investigation of the Jan. 15 battery incident involving an All Nippon Airways B-787. Both investigations remain ongoing.

 

NTSB urges redesign of Rolls-Royce 777 engines

The National Transportation Safety Board (NTSB) (Washington) has issued an urgent safety recommendation for the redesign of the Rolls-Royce engine component of Boeing 777 during the next maintenance cycle or within the next six months. This recommendation comes after its investigation of two 777 engine failure incidents, the January 17, 2008 dual-engine failure and crash at Heathrow Airport of a British Airways Triple Seven and a November 26, 2008 single engine failure involving a Delta Air Lines 777-232 ER en route from Shanghai to Atlanta over Montana. It will now be up to the Federal Aviation Administration (FAA) to accept and implement the recommendation.