Showing posts with label RAT. Show all posts
Showing posts with label RAT. Show all posts

Thursday, November 11, 2010

Boeing releases more information on ZA002

Boeing came out what now seems like daily updates on their investigation into the fire about ZA002. Boeing is saying that the P100 panel that apparently started the fire in the electronics bay by setting an insulation blanket on fire. Boeing has removed the faulty unit and is sending a replacement unit to be installed in Laredo.

Boeing also states that while there is significant damage to the P100 unit, there doesn't seem to be much damage to the surrounding area or systems. Their investigation is still preliminary so there may be changes in this assessment as the investigation progresses. Boeing stated that they did find molten metal (aluminum according to Flightblogger) near the P100 panel but this was to be expected in light of the fire that took place. Boeing still stresses that their investigation of the area around the P100 panel including the composite fuselage is not completed yet and will take a few more days. They are also trying to assess repair time and plans as well as plans to return the test flight fleet to the air.

Here is Boeing's press release:

Updated Boeing Statement on 787 Dreamliner ZA002 Incident

EVERETT, Wash., November 11, 2010 - Boeing continues to investigate Monday's incident on ZA002. We have determined that a failure in the P100 panel led to a fire
involving an insulation blanket. The insulation self-extinguished once the fault in the P100 panel cleared. The P100 panel on ZA002 has been removed and a
replacement unit is being shipped to Laredo. The insulation material near the
unit also has been removed.

Damage to the ZA002 P100 panel is significant. Initial inspections, however, do not show extensive damage to the surrounding structure or other systems. We have not completed our inspections of that area of the airplane.

The P100 panel is one of several power panels in the aft electronics bay. It receives power from the left engine and distributes it to an array of systems. In the event of a failure of the P100 panel, back-up power sources - including power from the right engine, the Ram Air Turbine, the auxiliary power unit or the battery - are designed to automatically engage to ensure that those systems needed for continued safe operation of the airplane are powered. The backup systems engaged during the incident and the crew retained positive control of the airplane at all times and had the information it needed to perform a safe landing.

Molten metal has been observed near the P100 panel, which is not unexpected in the presence of high heat. The presence of this material does not reveal anything meaningful to the investigation.

Inspection of the surrounding area will take several days and is ongoing. It is too early to determine if there is significant damage to any structure or adjacent systems.

As part of our investigation, we will conduct a detailed inspection of the panel and insulation material to determine if they enhance our understanding of the incident.
We continue to evaluate data to understand this incident. At the same time, we are working through a repair plan. In addition, we are determining the appropriate steps required to return the rest of the flight test fleet to flying status.

Boeing will continue to provide updates as new understanding is gained.

Dominic Gates of the Seattle Times has a very detailed report up as well. In it he says that he has access to Boeing photos showing the damage to the P100 unit including damage to the contactors within the unit which close and open circuits when power is needed. Dominic also said that the insulation blanket which caught fire was placed between the P100 unit and the composite fuselage skin. Once the pilots cut power to P100 (which is on the left side of the airplane), the P200 unit which is on the right side of the airplane provided power as did the aircraft's APU (auxiliary power unit) and RAT. This is why the aircraft was able to land safely with power.

You can read Dominic's article below:

Dominic Gates: Boeing photos show damage to key 787 electrical components

Additionally, Flightblogger has posted his update as well:

Flightblogger: A Closer Look: 787 fire investigation points to P100 power panel

I've added Guy Norris' report that he put out this morning:

Guy Norris: 787 - new detail of fire and damage on ZA002