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In 1996 just before swissair signed an agreement with IFT (Interactive Flight Technologies-CEO Michail Itkis)to install the power sucking IFEN's on their aircraft, a report that specifically mentioned IFT by name was submitted. The strange part is that the installation of these systems was done completely ignoring the safety measures set forth in this report. In fact it was almost done in the exact opposite manner that was suggested in this report because the IFEN was too powerful for the MD-11 aircraft to support . So apparently even though those involved knew this, it was done anyway. It wasn't possible to install the IFEN safely in the MD-11 because it used too much power. All safety measures were apparently ignored. The pilots couldn't turn the entertainment system off even if it caught on fire. The purpose of this report was to get the US to accept gambling on foreign airlines which is still illegal to the best of my knowledge. Here is an old post from the sr111 board that comments on that report: As mentioned previously on your board, and in an article in Air Safety Week, there was a report prepared by the U.S. Department of Transportation (DOT) in March 1996, that was submitted to Congress titled " Video Gambling in Foreign Air Transportation " One month after this report was issued, Swissair signed an agreement with IFT to install video gambling systems in several of it's aircraft. Installation of Swissair's first entertainment network (aboard SR111) was completed within 9 months. That included it's design, certification, installation, and testing. Here are more excerpts from that 1996 report: ENSURING COMPLIANCE WITH TECHNICAL SAFETY REQUIREMENTS "One company - Interactive Flight Technologies, Inc. (IFT) -- recently obtained certification for an electronic entertainment system which includes a gambling feature. The process used to certify IFT's system demonstrates how FAA ensures the technical safety of entertainment systems." "IFT's system, dubbed the In-Flight Entertainment Network, was certified for installation on a McDonnell Douglas MD-11 presently operated by Alitalia Airlines..." "Because the installation of an electronic entertainment system is considered a major modification to an aircraft, as is the case with other electronic systems, the installation and operation of IFT's entertainment network was subject to FAA's issuance of a supplemental type certificate for the particular aircraft type. This certification process is initiated by an application to FAA and is multifaceted, requiring several interim approvals. It is a long-standing, standard process spelled out in detail in internal FAA operating manuals." "Martin Aviation, an FAA-approved representative, handled the supplemental type certification process for the IFT system (aboard Alitalia). FAA established the certification criteria necessary for approval, including the requirement for a flight test. FAA and Martin Aviation reviewed all the necessary certification and technical drawings, manuals, and procedures for adequacy and compliance. FAA issued necessary interim approvals, including permission to conduct a flight test; reviewed the results of the flight test; performed inspections to ensure that both the components of the entertainment system and its installation and operation conformed to the certification requirements; and issued the supplemental type certification." "Throughout this safety-certification process the primary concern was to ensure that the entertainment network performed its intended function and did not interfere with the intended functions of other aircraft systems or with emergency procedures. In particular, scrutiny was accorded to whether the entertainment network would interfere with the operational and navigational equipment installed on the aircraft; whether the electrical components of the network were compatible with the aircraft; and whether the the network would generate any type of electromagnetic interference. Other factors examined were whether the entertainment network would provide any unusual drain on the the aircraft power system..." Here's a couple more paragraphs for thought... "Further, should an aircraft malfunction occur, the entertainment network would automatically deactivate by removal of power from the main power distribution." Don't they really mean: "Further, should an entertainment network malfunction occur, the aircraft's flight instruments would automatically deactivate by removal of power from the main power distribution."??---------------------And how about this one? "The system also includes a selective disable function allowing the gambling feature to be deactivated at individual seats."Ironic isn't it, that the flight crew themselves were unable to disable it as easily as this? FACTS List Pertaining to the IFEN installed on sr111: Now look at this list of FACTS (mostly information from van Beveren)and note the difference of how the IFEN was actually installed on the sr111 aircraft: FACT 1:IFEN system was connected to an essential bus on SR111 (and 15 other MD11 sisterships). FACT 2:IFEN is in question as an ignition source on SR111. FACT 3:IFEN could not be successfully deactivated by the crew, given the checklist procedure, since it was connected to an essential bus instead of a cabin bus (which is how it is normally done because an IFE is obviously a non-essential item for flying an a/c.) FACT 4:Wiring for the IFEN was improperly mixed with the harder Kapton insulated wire in the installation and bent at 90 degree angles against the recommendations of the manufacturer, McDonnell Douglas.Patrick Price said it's also evident installers used pliers to bend the wires, another faux pas. "You don't dare do that with insulation material -- you might damage it," said Price(Canadian News) FACT 5: It was reported in a 1997 swissair internal newsletter that swissair was in a hurry to have this IFEN/IFE installed on their MD11 aircraft. (Source; David Evans, Air Safety Week) FACT 6 In late October of 1998, Swissair disconnected the entertainment system on their remaining fleet of MD11s (15 sisterships)because the investigators found the wiring to this system (tefzel) as well as Kapton wiring in the forward section of the plane to have traces of electrical arcing. FACT 7 The FAA has issued an AD prohibiting the use of this IFEN/IFE ( unique to swissair), to be used on commercial a/c. FACT 8 The FAA (see Evans/Wojnar interview), stated that the IFEN/IFE was incompatible with the electrical design philosophy of the airplane.* FACT 9 SBA was both the STC applicant and the approving organization under their DAS.* FACT10 Santa Barbara Aerospace who issued the certification for this system, surrendered the DAS on July 1, 1999. The latest status is that SBA has declared bankruptcy and shut the doors.* FACT11 Within hours after the crash, before the burnt wiring was discovered by the investigators, the FAA was looking at the supplemental type certificate (system) installed on the accident aircraft.* FACT12:The FAA stated (Wojnar) that the installers of this system (Hollingsead) 'didn't use good industry practices for the installations on the wiring'.* FACT 13:"The entertainment setup, whose power supply runs through the cockpit, was identified as one system with sufficient electrical energy to disrupt power to the affected flight deck units and with components in a position to feed smoke into the cockpit, but not the cabin. TSB officials said they have no evidence that the smoke infiltrated the passenger cabin." (Source Aviation Week) FACT 14: Qantis elected not to purchase the IFE system from IFT because they determined that the system required too much power usage.(Source; FACTS) FACT15: Though pulling the IFEN circuit breakers (the only means Swissair flight crews had of removing power to the IFEN) was a part of the 'parking checklist', it was not added onto the emergency checklist. It should be noted that aircraft circuit breakers (CBs) should not be used as switches. They were not designed to be used that way and constant use will increase the failure rate of their primary function. 'Frequent action of the circuit breaker can lead to 'floppy' action and CBs so used may fail to pop when they should. When the circuit protective device fails to open a faulty circuit, one can reasonably expect electrical fireworks to result. Fireworks may occur at the distribution bus, the loss of which means loss of systems en masse.' Source:Air Safety Week. FACT16: The Federal Aviation Administration (FAA)proposed 14 airworthiness directives (ADs) that would ensure flight crews have the ability to shut off in-flight entertainment systems on several transport aircraft models when necessary. An extensive review of current in-flight entertainment systems revealed that these systems can remain powered despite current flight crew procedures.(source:FAA) FACT17 “During the introduction to service of the MD-11 IFEN, in the spring of 1998, numerous problems with overheating of the IFEN had been experienced. The SR MD-11 Chief Pilot later admitted (in an Air Safety Week interview) that they had had to vary the operating range of the MD-11's air-conditioning control selections in order to overcome this.” (Source:Tim van Beveren) *Source: David Evan's(Editor of Air Safety Week)Wojnar(deputy director, aircraft certification service,FAA)interview http://www.aviationtoday.com/reports/wojnar.htm From Air Safety Week regarding the Gambling Report: Famous First Words A highly-pertinent example of the kind of hazardous infringements Aubury was talking about, and the need for competent and rigorous regulatory oversight, involves the installation of the interactive in-flight entertainment network (IFEN) in the Swissair MD-11 that crashed in Halifax, Canada, Sept. 2, 1998. While the source of the electrical fire has not yet been determined, the IFEN was among the earliest suspects. Its installation was approved via a Supplemental Type Certificate (STC) by the Federal Aviation Administration in September 1996 (see ASW, Sept. 13). Just six months before, in March, 1996 the U.S. Department of Transportation (DOT) submitted a report to Congress titled "Video Gambling in Foreign Air Transportation." The report was a response to Congressional concerns about the passenger behavior and the flight safety aspects of systems precisely like the IFEN installed in the Swissair jet. Contrast the report's bland assurances with the blunt post-crash assessment of the FAA's special IFEN certification review team: March 1996, DOT video gambling report. "The entertainment systems in operation today, including ones with a gambling feature, have been certificated as safe...by the FAA. FAA assesses technical risk in accordance with...a well-established certification process. Under this process, an entertainment system proposed for installation on an aircraft is evaluated for electromagnetic interference with other equipment on the airplane, electrical power loading on the aircraft's power generation and distribution system, the potential for fire hazard, potential interference with emergency procedures and passenger evacuation, and other factors affecting the safe operation of the aircraft." June 1999, FAA Special Certification Review Team report. "The current design of the IFEN system electrical power switching is not compatible with the design concept of the MD-11 airplane with regard to the response by the flightcrew to a cabin or flight deck smoke/fumes emergency. In addition, the current IFEN system design does not provide the flightcrew and/or cabin crew with the ability to remove electrical power by a means other than pulling system's circuit breakers." More than a year after the Swissair crash, the FAA voided the IFEN system STC in a Sept. 28 airworthiness directive (see ASW, Oct. 4). ----------------------------------------------------------------\ ---------------- | |||
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To view a copy of the 1996 "Video Gambling in Foreign Air Transportation" report: http://ntl.bts.gov/data/gambling.pdf http://www.bts.gov/ntl/data/gambling.pdf | ||||
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FACT15: Though pulling the IFEN circuit breakers (the only means Swissair flight crews had of removing power to the IFEN) was a part of the 'parking checklist', it was not added onto the emergency checklist. It should be noted that aircraft circuit breakers (CBs) should not be used as switches. They were not designed to be used that way and constant use will increase the failure rate of their primary function. 'Frequent action of the circuit breaker can lead to 'floppy' action and CBs so used may fail to pop when they should. When the circuit protective device fails to open a faulty circuit, one can reasonably expect electrical fireworks to result. Fireworks may occur at the distribution bus, the loss of which means loss of systems en masse.' Source:Air Safety Week. Here is some updated information regarding circuit breakers that appeared in Air Safety Week this week: More Attention Needed for Safe Functioning of Circuit Breakers Along with the tremendous attention paid to the state of aircraft wiring over the past three years, a small side effort has focused on the condition of circuit breakers. The news is mixed. They hold up under conditions and practices that are better avoided. Circuit breakers, also known as circuit protection devices, generally seem to retain their basic function with years of service, unlike the cracking, chafing, and other problems that can afflict wire over time, and which has been documented in both large and small transport aircraft (see ASW, March 19, 2001 and Jan. 27). And, to be sure, circuit breakers mounted in racks offer less opportunity for the kind of installation mayhem that has been found with wiring, such as wires that run alongside fuel lines, next to heat sources and right alongside sharp metal edges (see ASW, Jan. 27). Nonetheless, circuit breakers cannot be ignored. They should not be used cavalierly as "on-off" switches, and they should be kept free of dust, dirt, grease and other contaminants that can create a fire hazard. These are the main findings of a recent study conducted at the William J. Hughes Technical Center near Atlantic City, N.J. The center is operated by the Federal Aviation Administration (FAA). The aircraft age-related circuit breaker degradation study (Report. No. DOT/FAA/AR-01/118) was based on detailed examinations of circuit breaker panels removed from a 29-year-old B727 with 58,800 flights and more than 66,000 flight hours, and from a 28-year old DC-10 with about 25,860 flights and 73,600 flight hours. The breakers were examined as installed in the panels, to include by x-ray, and their electrical functioning was tested. Don't replace, periodically cycle The good news is that their electrical functioning, in terms of the usual tests for voltage drop, minimum and maximum trip limit, and overload current trips (a test designed to prevent nuisance trips), were generally within the breakers' design specifications. The study concluded: "The circuit breakers in aging aircraft have not exceeded their design limits for protecting the wire from slight increased current levels caused by aging of the electrical distribution system. Based on the results ... it is recommended the breakers not be replaced." Rather, the study found that periodically cycling the breaker can actually improve its 200 percent lower current overload characteristics and therefore recommended "the breakers not be replaced but periodically cycled on and off." A Tech Center official explained that breakers can trap debris, so it is important to periodically "make sure they function manually." If used as a switch, install a switch However, the study warned against frequently cycling breakers by using them as the functional equivalent of "on-off" switches. Breakers are designed to handle a certain number of on and off cycles, say 5,000 for a resistive load and 10,000 cycles with no load, but "a switch is typically designed for endurance four times that of [a] circuit breaker." A breaker used as a switch can reach the 10,000-cylce limit "pretty quickly on some aircraft," the Tech Center official said. The study found one breaker maddeningly continued to pop open during routine preparation for a low voltage test. Upon closer examination, "excessive wear of the latching mechanism" appeared to have been caused by "excessive on and off cycling of the breaker," the study noted. If a circuit requires routine on and off action, use a switch, the study recommended. Clean as you go The study found that roughly 50 percent of the breakers removed from panels were exposed to dust or small particles, which evidently accumulated over time after aircraft delivery. It was apparent that liquid contamination and copper particles found on the breakers were deposited during maintenance. Overhead panels seemed to provide the best traps for dust and small particles, as these panels had the most of both. The study team reviewed maintenance manuals and found no clear specifications "that panels be routinely cleaned and protected when exposed to maintenance activity behind or above the panels." Yet, as the study team noted, contaminated breakers "may develop voltage arc-over, current seepage, internal corrosion, and dry closure problems." For these reasons, the report said, maintenance manuals "should include clear instructions on how to protect the panels during maintenance actions." Moreover, the area behind the circuit breaker panel should be cleaned and vacuumed "at least once a year." As reported previously in this publication, the areas behind some panels of high-time jets have been found buried under an inch-thick layer of dust - a serious fire hazard in the event of electrical arcing (where the spark is the "match" and the lint serves as "tinder"). Installation issues The study found two major types of installation problems. Of the 316 breakers that were evaluated, "many of the lugs contained two wires and had two different size conductors." In addition, the study found, "In two cases, a terminal had three wires, and in one case a terminal had four wires ... Depending on [the] amp rating, the categories would include signal and power circuits." The Tech Center official recounted that for the most part these cases of multiple wires connected to one breaker result from supplemental type certificate (STC) modifications. "It is not necessarily dangerous, but it is not recommended," he said, explaining, "When you have all this thermal mass on one lug, [it] can throw the circuit breaker out of calibration." The Federal Aviation Regulations (FARs) clearly state that each circuit for essential loads will have an individual breaker (FAR 25.1357). The study cited two Society of Automotive Engineers (SAE) aerospace recommended practices, ARP 1199 and ARP 4404, saying both documents imply that each circuit should have its own breaker but neither standard provides any guidance "on when multiple conductors on a single breaker should be used." The study said that the SAE committee responsible for the 1199 and 4404 recommended practices should "develop clear guidelines on when multiple circuits on the same breaker should and should not be permitted." The study team found numerous instances where the breakers were darkened, indicating excessive heating, as well as the telltale evidence of electrical arcing, indicating loose terminals. "The darkened areas may be due to chemical oxidation," a sign of exposure to high temperature. "Metal oxides are often nonconductive or semiconductive films that increase the resistance or voltage drop of the circuit, in turn increasing the potential for localized resistive heating," the study said, presenting a "worst-case example" of its concern. Yet maintenance manuals "do not require inspection of circuit breaker panels for signs of overheating or arcing," the study noted, adding that guidance needs to be provided "on what to do" when these indicators are present. The study found numerous examples of stripped threads and other problems of wire-to-breaker connectivity, including broken lock washers, missing lock washers, washers against terminals and not lugs, and so forth. "Aircraft maintenance manuals do not clearly specify that securing hardware should be replaced with identical parts, and there is no established process to permit substitutions until such time that the identical part can be added," the study concluded. In brief, the study found plenty of room to reform maintenance practices, and when breakers are used routinely as switches, they should be replaced with purpose-designed switches on a scheduled basis. The industry hopes that arc fault circuit interrupters (AFCI) will offer a leap in electrical system safety, as they will mitigate the hazard of "ticking faults" and will act faster in the face of arcing than is the case for today's thermally-activated devices. However, AFCI technology is years away from deployment. The recent study of age-related breaker degradation shows the need to upgrade awareness and standards of breaker husbandry today. This complementary activity can improve electrical system safety quite independently of the installed state of breaker technology. Circuit Breakers 101 There are several different designs of circuit breakers, but the most commonly used type ... depends on a thermal-sensing element to release. Typically, the sensing element is a bimetal strip, which opens the electrical circuit at a predetermined calibration point based on a temperature rise caused by load current heating. The electrical designer must choose a circuit breaker rating that matches the wire size the breaker is trying to protect. If the wire size is too small or too big for the breaker, the heat sink characteristics of the wire will shift the calibration curve up or down, respectively. If the wire is too big, the breaker will respond more slowly to a current overload, thus inadequately protecting the wire. If the wire is too small, the breaker will open earlier than designed, potentially causing electrical system malfunctions. Although it is generally not recommended, when multiple wires are used on the same breaker ... the breaker must be chosen to protect the smallest wire size ... and the heat sink characteristics caused by the multiple connectors must be taken into account. This is ... one of the principal reasons why wire ... is always replaced with the same size wire ... in order to prevent safety problems. Source: Aircraft Age-Related Degradation Study on Single- and Three-Phase Circuit Breakers, November 2002, Report No. DOT/FAA/AR-01/118, p. 8 | ||||
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