NEW CVR and DFDR RULES Proposed.. and they stink |
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WHY DON'T THEY DO IT SENSIBLY? (why always the predictable, half-baked, unworkable, cheap-charlie solutions? - see second panel) If you think about this mooted (i.e. proposed 2005) change (see below, next panel), it doesn't make a lot of sense - for the following reasons: a. Airlines are bucking for (and have been granted) extensions to the present ETOPS rules (i.e. for extended range twin-engined overwater ops there are tracking limits for max ranges from enroute airfields). All the airlines have to do is prove statistically that historical engine shut-down rates are within reasonable limits. The possibility of cabin or cockpit fires does not enter into this equation. b. Aircraft that disappear enroute beyond radar range may never be located. If SR111's fire had happened 90 minutes further on down track it would have simply vanished. Its final 10 minutes of incommunicado flight could well have been 10 mins or 70 mins - as far as search authorities would have known. As you are aware, there were also lots of deficiencies with its EPIRB (Emergency Position Indicating Radio Beacon). It would have vanished off the face of the Earth (and CVR and DFDR's would never have been recovered). And yet another MD11 IFEN-inspired accident may then have happened routinely because of that sort of eventuality. The same logic applies to terrorist bombs, fuel-tank explosions, hijackings, pilot suicides, clear air turbulence induced structural failures etc. SO WHAT IS THE ANSWER? With some minor technological interfacing, any crew experiencing "PAN PAN PAN" type (or worse) difficulties should be able to select the appropriate ATC transponder code and have both their CVR and DFDR data-dump auto-uplinked via data-link to their own airline's operations site (anywhere on earth). This would include current GPS positional data and so, in the event of a crash, provide a precise crash location (with the proper electrical powering provisions, that is) - and the possibility of more rapid succour for any survivors. You could extend the auto-uplinking initiators to include: a. rapid depressurization (structural failure, system failure or bomb detonation) b. Cargo hold smoke detector initiation c. G excursions (severe turbulence, loss of control, control failure [such as rudder hard-overs]) d. Crew removal of smoke masks, EVAS or hand-held fire extinguishers from stowage. e. Parameter exceedances (slats, flaps or undercarriage extending at high speed etc) f. Rapid-Rate emergency descents g. Aircraft stall stick-shaker actuation h. Fuel dumping i. Loud Noises (gunshots, explosions, structural failure) j. It should also be able to be reverse-initiated by ATC (via transponder responses) (eg if hijacking suspected because of diversion from track or nil comms). To protect pilots' privacy, as now happens, access to CVR data would be crypto-limited to accident investigators or (in the event of an incident) to the pilots' concurrence or a court-ordered review. If you have problems getting your mind around this concept, just think of it as an IRIDIUM mobile phone sending data-streams (versus pure digital voice). It's technologically feasible but I'm pretty sure it's not in the FANS-1 or -2 masterplans. And it makes more sense than NTSB's recommendations (see below) for 6 year's hence. It solves the perplexing problem of massive, costly searches and months of puzzling over expensively salvaged (but incomplete) debris. The savings should be considerable in terms of money, protracted doubts, crew uncertainty and passenger anxieties. It should also reduce the hazards to both searchers and retrieval crews. It would tend to minimize families' anguish if the cause were known rapidly -by virtue of the revealing DFDR data-stream and interfaced CVR transcript. The torture of an air-crash is all the more agonizing because of the years of waiting and speculation - normally followed by a "probable cause" and further years of lawyer-enriching argumentative litigation. Another big plus for this solution is that it (the individual aircraft's system) can be tested and proved at regular intervals. Maybe then you wouldn't really need to carry the proposed multiple systems - because that costs payload over the many years of airframe revenue operation. How many times have CVR's or DFDR's been found deficient or damaged beyond info retrieval? How often have incidents gone on beyond the 30 minute CVR rota and important facts, background noises and aural data been then irretrievable? In the event of an inflight technical conundrum, Boeing or Airbus can plug into the data-stream, analyse the data and advise the air-crews. Cynically viewing the possibilities, I suppose you could say that convening the Court of Inquiry before the crash-landing can ensure the widest possible distribution of blame and responsibility. That should be popular with crews (whether they survive or not) because it will put paid to a lot of the Monday morning quarter-backing and 20/20 hindsight. The percentage of accidents attributable to pilot error may then become a more solid figure. At present it tends to be fattened unfairly because it's a popular "fall-back" position (cf the early B737 rudder accidents). Airline Operations Staff will shortly be retrieving real-time engine and systems data inflight for crew, aircraft operational, and maintenance scheduling purposes. Not to extend this capability, such that it could carry CVR, GPS and DFDR data for underway abnormal operations, would be irresponsible. This NTSB Proposal sounds more like a favoured Avionics Manufacturing Firm has put forward a new expensive piece of kit as a result of the palpitations over SR111's CVR/DFDR failings - and sold it to the NTSB as a tailor-made solution. The FAA will "buy" it and endorse it because it just happens to be going through one of those phases where "long-winded" six year solutions are facile avoidances of short term criticism (for alleged habitual inactivity). It really warrants more thought than it's obviously not been given. |
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Talk back! Wednesday, March 10, 1999 Make black boxes better - TSB Recorders should tape for at least two hours, have separate power, board recommends By RICHARD DOOLEY -- The Daily News The agency leading the investigation into the crash of Swissair Flight 111 is recommending sweeping new rules to cover the operation of flight-data and cockpit-voice recorders - an aircraft's so-called black boxes - aboard passenger planes. The Transportation Safety Board is recommending to Transport Canada recorders be modified so critical clues to the cause of a crash will not be lost. Specifically, the board is recommending: Cockpit-voice recorders have a two-hour recording capacity instead of a 30-minute continuous-loop magnetic tape. Planes required to carry both cockpit-voice recorders and flight-data recorders be fitted with voice recorders with a two-hour recording capability. Black boxes must also be fitted with independent power sources able to keep the units running for at least 10 minutes if an aircraft's power supply is interrupted. The United States National Transportation Safety Board made similar recommendations to the Federal Aviation Administration yesterday. TSB lead investigator Vic Gerden told The Daily News in December the investigation could lead to changes for flight recorders. The investigation into the cause of the crash of Flight 111 off Peggy's Cove Sept. 2 has been dogged by missing information from the Boeing MD-11's black boxes. The plane's flight-data recorder and cockpit-voice recorder stopped working six minutes before the plane plunged into the ocean, killing all 229 people on board. The flight crew had reported seeing and smelling smoke in the cockpit 16 minutes before the plane crashed. Without definitive recorder information, investigators have to rely on traditional methods of investigation, including reconstructing portions of the aircraft. "If the equipment we are recommending had been placed on Flight 111, we would know what went on in the last six minutes of the flight," said board spokesman David Austin. It would also give investigators valuable clues to what was going on aboard the aircraft long before it reached the coast of Nova Scotia. Investigators are curious why Flight 111 would not respond to air-traffic controllers in Boston nearly an hour before the crash. Boston Centre made repeated attempts to contact Flight 111 for 13 minutes as it flew through its area, 38 minutes before smoke was reported. Because the cockpit-voice recorder overwrote any subsequent conversations or noises in the cockpit, investigators don't know why contact with the plane was lost during that period. Transport Canada requires Canadian-made aircraft to have flight recorders supplied from different electrical sources and is co-operating with international aviation agencies on flight-recorder issues. Investigations into several crashes have been hampered by incomplete flight- recorder information, including the crash of a ValuJet plane in the Florida Everglades and the crash of TWA Flight 800 near Long Island, N.Y. in 1996. Many airlines are voluntarily replacing black boxes with solid-state recorders. |
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