主题：【原创】水牛城Colgan3407航班坠机事故 -- Slay0r
家园 今天的华尔街日报有一篇文章 The captain of a commuter plane that crashed Feb. 12 near Buffalo, N.Y., had flunked numerous flight tests during his career and was never adequately taught how to respond to the emergency that led to the airplane's fatal descent, according to people close to the investigation.机长在多次考核中未能过关，公司也从来没有培训他在自动推杆系统启动后应该如何反应。
The crew initially didn't notice the plane's speed had dropped dangerously low, sliding under 115 miles an hour, and risked going into a stall. The slowing speed set off an emergency system called a "stick-pusher," which pushes the control column down in order to send the aircraft into a temporary dive so it can regain speed and recover from a stall.However, Capt. Renslow tried to force the plane to do the opposite. He yanked back on the controls while adding thrust. His effort was strong enough to manually override the stick-pusher. Within seconds, the plane lost lift, bucked violently and started to roll. It slammed into a house five miles from the runway.
机组未能在第一时间发现飞机速度过低，已经接近失速速度。当自动推杆系统启动，使飞机低头加速时，机长手动拉杆抬机头并增大发动机功率企图爬升，致使飞机失速坠毁。
Investigators surmise the pilots didn't fully understand the operation of one ice-protection system, and therefore incorrectly programmed approach speeds into a flight computer. Startled by an initial stall warning at low altitude, Capt. Renslow reacted with the mistaken assumption that ice accumulation on the tail caused speed to suddenly drop well below normal, investigators believe. The NTSB has said the plane wasn't significantly affected by icing.机组错误计算了防冰装置开启时的进场速度，导致进场速度过低而自动推杆系统启动。机长错误地认为这是由于尾翼结冰而引起，(从而采取了错误的拉杆措施，)其实飞机结冰情况并不严重。
- -- 系统屏蔽 --。
- 复 拉杆没啥不对呀
家园 拉杆确实不对 一旦升降舵配平之后，调整节流阀（油门）并不会显著改变空速而更多的是调整下降速率，就是说踩油门的效果更大的是上坡而不是平地加速。而强行拉杆改变的是飞机俯仰角度，在低速时不会让飞机爬升多少只会显著降低空速。知道F86是怎么打歼5的吗，偷袭完之后俯冲加速逃脱啊，俯仰角度对速度的影响比开加力的效果显著得多。另外加油门之后飞机需要一定时间来获得动能，并不是马上生效，因此即使先加油再拉杆，只要间隔很小也会失速。
简单来说就是在稳定飞行的前提下，油门控制升降而操纵杆控制速度，这跟一般的直觉和常识是相反的。当然，推重比大于1的战斗机在机动时不是这样，那完全是另一回事。
- 复 拉杆没啥不对呀
家园 You need several seconds for the engine to rev up from flight idle and for airspeed to build up, the PIC most probably didn't give that few seconds...
家园 还有几个不可思议的地方 一个是女副驾居然家在西雅图，飞这班航班前先搭Fedex货机到孟菲斯，再转机到纽瓦克，花了一个晚上横穿美国大陆，这个大概可以创上班路途最远的吉尼斯纪录了，
二是飞行员的工资很低啊，
In the crash, the first officer, Rebecca L. Shaw, 24, a Colgan employee for about a year, apparently pulled an all-nighter to get a free transcontinental trip to work. She was living near Seattle and commuting to her job at Colgan’s operation in Newark, according to board investigators. She flew from Seattle to Memphis in a spare seat on one FedEx jet, and to Newark on another, planning to sleep in a crew lounge, investigators said. The airline said Wednesday evening that her rate of pay, for a minimum of 75 hours a month, was $23,900 a year.
家园 嗯，就这两天照计划NTSB该出来做一个先期调查报告了 飞行员误把Stick－pusher的低头当作水平尾翼失速来纠正的，所以拉杆纠正使飞机完全失速也是有可能的。
那就必须要知道为什么飞机在正常情况下（结冰不严重）飞机速度会低到如此程度(导致Stick－pusher启动）。Deicing开启绝不会导致这么大差别。文中错误的输入进场速度更是无稽之谈，Q400上有没有自动油门是我最早关心的一个问题，目前可以肯定的说所有DASH8Q400上都没有自动油门，即使AP被开启，飞行员也必须通过观察空速表手动控制油门和桨距来调整速度。
另外飞行员为什么没有注意到速度已经很低了，都是数千小时的飞行员，留意空速应该都已是本能，而放起落架和襟翼都有特定的速度要求，怎么放下起落架的时候不看，放下襟翼之前也不看？
家园 【讨论】西方人比较习惯用自动驾驶降落 西方人比较习惯用自动驾驶降落，中国大陆比较习惯手动落地，不过现在国内出去学的飞行学员也多了，也要被西方习惯影响了...
家园 我觉得倒不是自动驾驶仪的错 上一期国内《航空知识》介绍过这个空难。直接原因的确和自动驾驶有关，当时飞机已经严重结冰，不过自动驾驶仪补偿了这个影响，直到机组人员发现结冰报警杆震动，试图手工操纵时，补偿过量。
但归根结底应看作是机组人员的经验和应变能力的问题，文章中源引最近在河上漂亮迫降的那个飞行员的话“上个世纪的美国民航飞行员有90%是军队退役的飞行员，他们组成了民航飞行员的灵魂，现在这个比例已经30%不到了”。作为部队飞行员，和经航校出来的飞行员重要的区别在于心理素质和应付复杂情况的经验，这些是一般航校无法提供的能力。国内现在估计民航和美国上世纪的情况差不多，所以安全上反而还是有保障的，毕竟国内不像美国，随便哪个人都可以摸到飞机。