FUEL TANK SAFETY / EWIS CONTINUATION TRAINING

Transcription

1 FUEL TANK SAFETY / EWIS CONTINUATION TRAINING Q1 & Q Page 1 of 11

2 CONTENTS: 1 INTRODUCTION 2 LOCATION OF CDCCL OPERATOR DOCUMENTS 3 EWIS MOR 4 FIRE SAFETY INITIATIVE 5 MOE CHANGES TO CDCCL COMPLIANCE Page 2 of 11

3 1. Introduction The purpose of this module is to highlight industry issues related to SFAR 88 & EWIS. 2. Location of Operators CDCCL Documents Page 3 of 11

4 3. EWIS related MOR ALT Fuel Tank Safety / EWIS Continuation Training. The following are maintenance related extracts from the UK CAA MOR data base related to the EWIS on various aircraft types. The information is protected by the UK CAA and the monthly digest are now strictly controlled by them. It is respectfully requested that with this in mind, the content of the following is not copied or distributed in any way. A330 Voyager During fault investigation into fluorescent lighting tube evidence of arcing was found on floor lighting wiring. During fault investigation into fluorescent lighting tube, wires were found to be completely burned through approx 8in from ballast unit, as a result of electrical arcing, presumably between the two cables. Further investigation revealed problem caused by proximity of cable bundle routeing to a tie rod, which was found to be hard against one of the cable bundle tie-wraps securing the protective conduit around the cable. Visual examination revealed further insulation damage to the twisted pair data cables in the area of the arcing, and a hole burned clean through the split conduit protective sheath. There were no reports of the associated C/B tripping at any point, which indicates a failure of associated circuit protection in this case. Supplementary 20/01/14: No further anomalies have been detected in the wiring of the ballast unit. All aircraft have been manufactured in accordance with definition in original Design Office Drawings. CAA Closure: No root cause could be defined and it has been considered as an isolated occurrence not leading to a potentially unsafe condition. British Airways B767 Water damage and ingress found in the MEC area following flooding of forward galley, door 1L area. Wet carpet and floor covering in the door way with the door scupper drain channel blocked and backing up. Drain water leakage was evident with two wiring bundles wet in the area just aft of the EICAS computers and their drip shield. Evidence of previous leakage was found on the structure directly below the drain funnel and ragged edge corrosion was evident on a vertical flange of a plate/angle on the forward edge of the scupper drain funnel. Recurring problem. CAA Closure: Investigations found that the spillage was due to the forward scupper drain being blocked by an unknown material. The floor membrane was also not sealed correctly on the aft edge of the toilet, allowing water to penetrate. The membrane was resealed. The water ingress was found on two wiring harnesses between BS266 to BS287. These harnesses were cleaned and dried, with no additional findings. The aircraft type is acknowledged to have narrow drain lines, which are known to block and there are no modifications to alleviate this problem. The moisture shroud above the racks is also known to crack but there is a Boeing SB to address this which is currently being reviewed by the operator. Page 4 of 11

5 The cabin crew are regularly reminded not to throw certain liquids down the sinks and it is hoped that the introduction of the 'thirsty box' will mitigate some galley floods by providing an alternative means of disposal of waste liquids such as tea, coffee, orange juice, milk, wine etc. However, there is still a the requirement to put FRAKLEEN down the sinks, as this will continue to break down what is already lining the pipes and causing the blockages, as in this case. British Airways B777 EICAS alert 'Brake source' at 120kts on take-off. Take-off continued. Engineering reported that aircraft had a 'long history' of 'brake source' EICAS messages and had ADD's to this effect. CAA Closure: The aircraft had been experiencing intermittent false brake source warnings since mid April Wiring had been checked and a pressure switch changed. Further extensive wiring checks found a wire trapped with degraded insulation in the P105 (left integration panel). This would have provided the earth for the indication circuit. The wire was repaired. It could not be determined when the wire became trapped. It is possible that is had occurred when the aircraft was manufactured in British Airways B777 Damaged wiring found on fuel quantity indication system RH centre fuel tank. Manufacturer informed. CAA Closure: The chafe was probably caused by the wiring being left with slack in a chafe zone post SB embodiment in May Defect corrected and no further action is planned as this is the first report across several other aircraft. The fleet will be monitored. Jet 2 B757 Electrical wires found cut and protected with heat shrink. No Tech Log entry/add for inoperative panel lights. On inspection of wiring on panel area the four wires from the a/c to the panel were found cut and protected with heat shrink. Reporter suspects cables severed at hinge point of door and were cut to prevent refuel C/B popping. CAA Closure: Review of the maintenance history noted that no entry for capping of these wires can be found. It is not known how long or why these wires were terminated incorrectly. Engineers have been reminded to remain vigilant for wiring issues and a wiring defects review will be carried out to work towards additional training for all Engineers related to the operators aging fleets wiring issues. British Airways B747 Flap drive caution on departure. PAN declared aircraft returned. EICAS caution on selection of flap 5. Outboard flaps affected, jammed in position. PAN declared, fuel dumped to landing weight, aircraft returned. Airport fire services in attendance. Aircraft had made an airborne return the previous day as a result of the same defect which had been investigated by engineering before departure. Page 5 of 11

6 CAA Closure: The wiring inside the conduit adjacent to the left outboard TE flap RVDT was inspected and found that the insulation and screen was damaged on wire nos W R/ B/303-20Y (ref WDM ). In addition the left Outboard TE flap RVDT connector DM7891 was also found in poor condition and replaced. British Airways B747 Wiring loom supports found loose/disconnected and to have caused wearing/chafing of elevator cables. During routine inspection of elevator cables, it was discovered that both inboard screws on the wiring loom supports had fallen out and the outboard screws were in only by two threads. As a result, the supports had been contacting the lock clad portion of the elevator cables and had worn these sections. Wear was found to be within limits. One screw and two washers were found on top of overhead bins. CAA Closure: The airline has concluded its investigation. It is believed that the reported condition was the result of insufficient torque being applied to the support bracket hardware following disturbance, during a shear tie maintenance input five years previously. It has concluded that although the reported condition is undesirable it is not considered that aircraft safety in this case was compromised due to system redundancies and limited impact on the elevator system. The discovery was made during routine maintenance programme inspection. It is considered an isolated event. Noting routine inspections cover the area. Any damage to the elevator control cables was minimal, passing AMM inspection for continued operation without replacement. Material loss on the support brackets is consistent with the materials used for the flying control cables and support brackets. Due to the passage of time, the contracted maintenance organisation has not investigated individuals but has used this event as a learning opportunity. British Airways A319 Engine fire detection wiring fault. During high power engine runs followed fitting of new engine nr2 Fire Loop A fault and a separate Centralised Flight Display System (CFDS) message regarding nacelle temperature sensor appeared. Wiring to Core fire detector element and nacelle temp sensor found crushed by C-Duct mating pads due to wiring had been incorrectly installed at the position where it is in a vertical run just fwd of the nacelle temp sensor connector. The wiring is part of the engine harness. Additionally 3 backshell wire clamps found excessively loose but wirelocked. Thomsonfly B757 Missing wire, possibly as a result of rat damage. We have found a length of wire, approx. 1 inch long, missing from the rear of an ARINC connector on the E2-1 rack. The wire is and it goes to D1583C pin 8. The wire couldn t have just snapped as there is no evidence of stretching and it was found tied into a loom. There is no evidence of burning/arcing or heat damage. The wire is a signal ground for the TCAS computer and Tech Support is investigating the purpose of this wire. During the check, we have started to uncover significant amounts of rodent droppings as well as other evidence of rodents. For instance, chewed labels, chewed soundproofing, nests and signs of damage to wiring. I strongly believe the damaged TCAS wiring is a result of rodent biting. I think the damage to the wire itself is probably of less concern now than this possible cause but it is very hard for us to ascertain whether the rodent(s) is/are still on board. Page 6 of 11

7 We can t tell how recent the droppings or damage are. I think we need to think about whether it is worth us having some of rodent traps on board our aircraft. While these cases aren t common, the effects could be severe. Whether they be damage to aircraft systems or the spread of diseases, especially among the engineers coming into contact with the faeces and urine. The damaged TCAS wire has been repaired. Thomsonfly B787 Dimmable window power cable broken with evidence of arcing. Broken wire discovered at splice, dimmable window 15GHJ. Suspect installation error at manufacture during making of splice. Cut wire adjacent to where screen cut back for solder sleeve screen. 28V power cable probably nicked. Wire eventually failed due to arcing/loom disturbance. Immediate corrective action taken. Wire to wire screened splice repair carried out. Rewire to dimmable window power 15GHJ. Manufacturer to review manufacturing procedures. This is the second wiring fault on this aircraft in the same circuit line originating from manufacture flaws. First solder sleeve pigtail. CAA Closure: The cause was determined to be an isolated workmanship error at the aircraft manufacturer where the wire bundles were disturbed after final installation. No other cases have been found post inspection. The manufacturer has issued Corrective Action Task to bring awareness to Final Assembly and Delivery, Delivery and QA. Other relevant notifications have been released to interested parties. B737 Jet2 VHF 3 wiring was found to be un-stowed inside the centre console and had end caps missing from wiring. Whilst carrying out checks on the VHF NAV Control panels in the centre console of the flight deck the VHF 3 wiring was found to be un-stowed inside the centre console and had end caps missing from wiring. VHF 3 has been removed from this aircraft but the wiring remains in-situ, however, it should be correctly stowed so as to prevent any damage occurring. In this instance it could have been possible for the looms to come into contact with other looms inside the console and cause damage or for the looms to fall through the access hole in the floor and restrict control cables. The wiring (plus D00549 and D02887) has now been correctly stowed. Investigation under Thomsonfly B787 Dimmable window power cable broken with evidence of arcing. Broken wire discovered at splice, dimmable window 15GHJ. Suspect installation error at manufacture during making of splice. Cut wire adjacent to where screen cut back for solder sleeve screen. 28V power cable probably nicked. Wire eventually failed due to arcing/loom disturbance. Immediate corrective action taken. Wire to wire screened splice repair carried out. Rewire to dimmable window power 15GHJ. Manufacturer to review manufacturing procedures. This is the second wiring fault on this aircraft in the same circuit line originating from manufacture flaws. First solder sleeve pigtail. Page 7 of 11

8 Monarch A330 Galley wiring found burnt. During investigation of Aft galley port side oven popping CB and Aft boiler 2 CB popped, Aft Galley No7 (R/H) found to have heavy burn/arcing damage to wiring loom adjacent to upper galley mounting bracket. Adjacent insulation blankets also burnt. Wiring does not appear to have chaffed on structure. Swiss BAe 146 RJ Damage found to engine FADEC electrical harnesses. This report is raised to advise of inspection arisings during maintenance. The topic & condition described is not limited to the subject aircraft registration. There is damage noted to be occurring to the Engine FADEC Electrical Harnesses in the Engine Pylon area. Damage has been discovered at each pylon position on the subject aircraft, but is being occasionally discovered at the same location on other aircraft of the Type. The noted damage occurs at location where the FADEC Cable Harness is routed over/adjacent-to the Starter Contactor power terminal stud. Typical damage is abrasion/chafing of the Harness outer Halar braid & the inner nickel copper braid, but damage to inner wiring insulation and electrical arcing/burn damage is also encountered. It is noted that some previous attempts to protect the harness at the location may have been employed by the addition of plastic Spiral-Wrap typical protection, but this does not appear to have afforded sufficient protection to avoid the introduction/progression of damage at this location. Due to the closeproximity of electrical wiring and other hardware routed through this upper-pylon area, the wiring could be susceptible to the damage onset by reduced clearances / disturbance / routing variations as known to present similar problems in the area. The reported damage is almost always at the point where the FADEC cable is routed over the Starter Contactor Power Terminal Stud. Differing Mod standards and Part Numbers of the FADEC Harness can exist on the installation on type but any may exhibit similar damage at this location. FADEC Harness Assy Part Nos C4 and also NC iss3. Typical. (Wiring Diagram Manual Ref WDM Zone Damaged Electrical Harnesses to be repaired/replaced as appropriate. Clearances & Routing Checked. Function testing as necessary. Recommend re-evaluation of routing/positioning to ensure FADEC Harness / adjacent hardware clearances are maintained. The reporting organisation suggests a possible contributor to the perceived damage may be disturbance during certain levels of maintenance, when access panels are removed and the wiring exposed to risk by any local maintenance activity. This to be further considered together with feasibility of use of suitable protection during local maintenance activity if necessary. In any case a specific risk of FADEC cable damage exists at the location. Maintenance/Inspection staff to be advised of specific problem by inclusion in the routine & EWIS continuation training programme. Thomsonfly B757 Fuel tank wiring harness damaged. Aircraft currently undergoing Winglet modification and additional work. During installation of L/H Wing Main Tank FQIS Wiring Harness found wire damaged. The wire insulation was damaged exposing the wire conductor. The area of damage is approximately 5mm between L/H wing stations and Wiring harness replaced. Page 8 of 11

9 Engineering report: An examination of the removed harness confirms that the wire insulation is damaged, although it is extremely difficult to tell if the conductor is exposed. As the harness had been removed and the damage only noticed during reinstallation, it is not clear whether the damage to the harness occurred whilst on or off the aircraft. An inspection of the left wing in-tank harness, is included in the maintenance program, but has not so far been carried out on this aircraft. This task has been carried out on twelve aircraft so far, with no findings. All records were also checked for damaged tank harnesses, but nothing was found. The cause of the damage to the cable could not be determined. British Airways A319 Galley boiler damaged/chafed wiring. Reference weekly check, cleaning of forward & aft worktop scupper drains. Cleaned forward galley beverage maker scupper drain, refitted beverage maker and reset C/B. When the C/B was reset there was a blue flash and a loud bang from behind beverage maker. C/B Pulled, beverage maker removed and on inspection of electrical components located behind the beverage Maker location, found damaged/chaffed wiring on the back of the connector. Potential Electrical hazard. Possibly due to method of drain cleaning Jet2 B757 Electrical wires found cut and protected with heat shrink. No Tech Log entry/add for inoperative panel lights. On inspection of wiring on panel area the four wires from the a/c to the panel were found cut and protected with heat shrink. Reporter suspects cables severed at hinge point of door and were cut to prevent refuel C/B popping. CAA Closure: Review of the maintenance history noted that no entry for capping of these wires can be found. It is not known how long or why these wires were terminated incorrectly. Engineers have been reminded to remain vigilant for wiring issues and a wiring defects review will be carried out to work towards additional training for all Engineers related to the operators aging fleets wiring issues. Page 9 of 11

10 4. Fire Safety Initiative ALT Fuel Tank Safety / EWIS Continuation Training. The potential risks fire poses to passenger aircraft has been placed centre stage in an awareness raising campaign by the United States Federal Aviation Administration (FAA) and the UK Civil Aviation Authority (CAA). The safety drive includes a short video that has just been released, identifying the specific maintenance risks that may cause onboard fires, such as dust accumulation and faulty electrical wiring. The film will be distributed to US and UK airlines and maintenance organisations to incorporate into their training regimes. The video highlights the importance of accurately following aircraft maintenance procedures and also ensuring that electrical wiring is not damaged or contaminated with grease or foreign debris in any way. The CAA and FAA already collaborate extensively on fire and cabin safety issues, with both regulators also engaging with Transport Canada and the European Aviation Safety Agency on fire-related workstreams. The UK regulator has also worked extensively with the aviation industry to explore mitigation measures for fire-risks. Indeed, the CAA has previously identified fire as one of the significant seven safety risks to commercial aviation, along with such threats as loss of control and runway excursions. Of particular concern is the threat of fires breaking out in hidden areas of the aircraft, which cabin crew are unable to access and bring under control in-flight. The importance of reducing fire risks was highlighted with the recent significant fire on the Ethiopian Airlines Boeing 787 on the ground at London Heathrow. As the film points out, an in-flight fire that is out of control will on average lead to flight crew losing control of the aircraft within 15 minutes. The five minute video is available to view at and the CAA s YouTube channel YOU CAN FIND A DIRECT LINK TO THE VIDEO ON TECHCOM, QUALITY, UK CAA DOCUMENTS Page 10 of 11

11 5. MOE Changes to Section 2 relating to CDCCL Compliance During a recent internal audit, it was identified that ALT did not comply with AMC 145.A.70 (a) with respect to how we detail our method of complying with CDCCL requirements. As a result, a small addition was made to the MOE detailing how ALT comply. The amendment was as follows: MOE 2.24 Page 11 of 11