* IAS = Indicated Airspeed = airspeed indicator reading.
* CAS = Calibrated Airspeed = IAS corrected for static position error.
* EAS = Equivalent Airspeed = CAS corrected for compressibility error.
* TAS = True Airspeed = EAS corrected for OAT and pressure altitude.
* GS = Ground Speed = TAS corrected for wind component.
* M = Mach number = relationship between TAS and speed of sound.
为什么其他的飞机不干脆直接安装类似的 pitot tube 呢？那个 engineer 解释说，那支东西看来很轻，其实它是很重的铁管，要将它 secure 在 nose cone 是一项很考功夫的任务。除了重量之外，那支东西还很难 maintain。所有的 pitot tube 和 static port 都是需要 electrically heat up (heating element 的功能也加重了它的重量)。普通小小支的 pitot tube 都会 overheat 或 heat failure的状况，那么大支的 pitot tube 肯定会更多问题。那么大支的 pitot tube 需要很大的 electric current 来发热，这将会提高其它 electrical problem 的机率。Galley 的 oven 时不时都会 trip 啦，那么耗大电的 pitot tube 会更多问题。Oven 坏顶多是没有热食物而已，不会有人死。Pitot tube icing 是会死人的 failure。
Airservices digs for safety improvements as mining charter sector expands
By Emma Kelly
Australian air navigation service provider Airservices Australia is calling for the "urgent fitment" of automatic dependent surveillance-broadcast (ADS-B) equipment to the country's fly-in, fly-out mining charter fleet - particularly in Western Australia - in light of the "explosive growth" in the sector.
Airservices chief executive officer Greg Russell said the growth in fly-in, fly-out operations is an immediate challenge to the service provider. Until now, Airservices has been using traditional procedural separation standards in managing regional airspace in Western Australia, particularly in the northwest of the state, where most of the mines are located.
However, the system is now close to capacity: "The industry is telling us that significantly more growth is going to occur in fly-in, fly-out operations in the next two to three years," Russell said. "Put simply, this cannot occur safely without a major change to the surveillance picture so we can see the aircraft involved, and that involves a programme of urgent fitment of ADS-B."
Australia has nationwide ADS-B coverage above flight level 300 (30,000ft/9,144m), and Airservices has long been keen to extend the programme below FL300. The company said it is in discussions with operators on the issue, and they are receptive to ADS-B.
The service provider held a regional safety forum to review current and future demand issues in Western Australia earlier this month, attended by more than 30 representatives of the mining and resources industry, airlines, charter operators and Perth airport.
Russell said in order to "buy some time" Airservices is installing a transportable radar in Paraburdoo, which will provide coverage of six airports within 100km (62 miles).
The growth of fly-in, fly-out operations is also putting a strain on Perth airport. Although the airport is currently operating at about a third of its capacity, the rostering of mining operations means there is major departure congestion between 05:30 and 08:00 on Tuesdays, Wednesdays and Thursdays.
"Aircraft leave and return to Perth in large waves, which exacerbate issues with ground infrastructure and cause lengthy delays," Russell added.
Perth airport is undertaking a Australian dollar 500 million ($515 million) redevelopment, including construction of Terminal WA - which will primarily cater for the resource sector's fly-in, fly-out market.
Over a million passengers are expected to use the terminal in its first year of operations in 2013.
How Airservices fixes the issues in Western Australia will provide lessons for other parts of the country, Russell said - with mining projects growing in Queensland and South Australia.
Japanese investigators have detailed the extraordinary in-flight upset involving an All Nippon Airways Boeing 737-700 which resulted in the aircraft banking to a near-inverted attitude.
Flight NH140 from Naha had been cruising at 41,000ft, en route to Tokyo on 6 September, and had been some 43km south of Hamamatsu when the incident occurred.
Japan's Transport Safety Board said the captain had stepped briefly out of the cockpit, but when he returned the co-pilot inadvertently operated the rudder trim control while attempting to let the captain back in.
The 737 banked slightly right, then twice rolled sharply to the left, achieving a bank angle of nearly 132° and "rapidly" pitching 35° nose-down, the inquiry board added.
It descended at high speed, losing 6,300ft before recovering at 34,700ft and climbing.
During the incident the aircraft, which had been on a heading of 052° north-east towards Tokyo, eventually stabilised on a south-west course of 257°.
In its preliminary report into the event the safety board said the aircraft had been on autopilot, but a left turn on the rudder trim control was recorded.
While individual configurations differ, both the rudder trim dial and the cockpit door lock switch on the 737-700 tend to be located towards the rear of the centre pedestal between the two pilots. The door switch requires a turn to the left to unlock the cockpit entry.
The aircraft involved, a four-year old twinjet registered JA16AN, achieved an excessive speed of Mach 0.828 during the event and experienced forces of 2.68g.
Inspectors assessed the aircraft's condition following the event but found nothing abnormal, said the safety board.
There were 117 occupants on board the aircraft, five of them crew members, but only minor injuries were sustained.
Further investigation by the Transport Safety Board will involve verification of its initial simulations, examination of the position of the trim control and cockpit door switch, and analysis of the radar track and radio communications.
Japan's Transport Safety Board said the captain had stepped briefly out of the cockpit, but when he returned the co-pilot inadvertently operated the rudder trim control while attempting to let the captain back in.
captain回去座位关copilot什么事？
While individual configurations differ, both the rudder trim dial and the cockpit door lock switch on the 737-700 tend to be located towards the rear of the centre pedestal between the two pilots. The door switch requires a turn to the left to unlock the cockpit entry.
Japan's Transport Safety Board said the captain had stepped briefly out of the cockpit, but when he returned the co-pilot inadvertently operated the rudder trim control while attempting unlock the cockpit entry to let the captain back in.
如果文章加入红色的那段句子，相信会有更多航空业以外的人能明白。自从911事件过后，所有的民航机的 cockpit entry 是会上锁。如果要打开，必须由 cockpit center pedestal 那里控制开锁。
While individual configurations differ, both the rudder trim dial and the cockpit door lock switch on the 737-700 tend to be located towards the rear of the centre pedestal between the two pilots. The door switch requires a turn to the left to unlock the cockpit entry.
翻译：
个别的飞机会有不同的 configuration (设定)，737-700上 的 rudder trim 和 cockpit door unlock switch 都是位于两个机师 center pedestal 的后方，门锁的 switch 须要扭转去左边来解开 cockpit entry 的锁。
All Nippon Airways Boeing 737-700 from Okinawa to Tokyo Haneda with 117 people on board was at FL410 when the aircraft violently rolled left causing injuries to two flight attendants and descended by about 6000 feet leveling off at FL350 again. The flight continued to Tokyo's Haneda Airport for a safe landing. The two injured flight attendants were delivered to a hospital with flesh wounds.
The airline reported, that the captain (64 years, 16,000 hours total experience) had taken a toilet break and was about to return to the cockpit requiring the first officer (38 years, 2400 hours total experience) to open the cockpit door. The switch to open the cockpit door is located about 10 centimeters/ 4 inches away from the rudder trim switch.
By mistake the first officer operated the rudder trim switch instead of the door opening switch causing the aircraft to violently roll left and descend by about 6000 feet before the first officer was able to return the aircraft to stable level flight. The captain subsequently entered the cockpit.
Two cabin crew received minor injuries (flesh wounds), no other injuries occurred. There was no turbulence in the area at the time of the occurrence. (Courtesy of the Aviation Herald)
Yes, this has also happened to one European airline before when the autopilot gave up on the full deflection of rudder trim as it was wrongly manipulated whilst trying to open the door.
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发表于 10-9-2011 03:23 PM
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