Not just C&D checks, oil tankers too. China has the advantage of infrastructure, skillset and low labor cost. US airlines are permitted to use certified foreign MRO facilities.
请楼主提供信息来源，除了美国自己，我看到的是美国各航空公司依赖三个国家（萨尔瓦多，墨西哥和中国）做飞机大修，其中AA多数在美国完成大修，UA用中国的，Delta在墨西哥做大修，不过，这个数据是2015年的，我不相信从2015年到现在，美国会把更多商业飞机送到中国做大修。 US Airways and Southwest fly planes to a maintenance facility in El Salvador. Delta sends planes to Mexico. United uses a shop in China. American still does much of its most intensive maintenance in-house in the U.S., but that is likely to change in the aftermath of the company’s merger with US Airways. 来源：https://www.vanityfair.com/news/2015/11/airplane-maintenance-disturbing-truth
所谓的ABCD检 Line Maintenance Checks This type of maintenance is the most routine. Sometimes called post-flight, maintenance pre-flight, service check, and overnight checks, this is the most typical maintenance service performed on aircraft. Line checks require minimal tools and are usually done at the airport gate under the “open sky.” Line checks happen the most frequently, as they cover basic inspection checks. Commonly, aviation maintenance technicians will inspect things like wheels, brakes, and fluid levels (oil, hydraulics) during line checks. Performing a line maintenance check ensures an aircraft is airworthy and safe to continue service. Aircraft need line maintenance every 24 to 60 hours of accumulated flight time, but it depends on the operator of the aircraft! A Checks The next level of checks is known as A checks. The A check is performed approximately every 400-600 flight hours, or every 200–300 flights, depending on aircraft type. A check maintenance is typically done at a hangar and can take a minimum of 10 working hours depending on the services needed. Sometimes, this maintenance is done overnight as to not interrupt the schedule that airlines keep. The frequency of this check varies by aircraft type, the flight cycle count, or the number of hours flown since the last check. The maintenance work during A checks often covers general inspections of the interior and the aircraft hull for evidence of damage, deformation, corrosion, missing parts. Additionally, it also includes service, engine, and function checks. Other work performed could entail things such as: checking emergency lights lubricating nose gear retract actuator checking parking brake accumulator pressure B Checks Next, B checks are often completed during the A check phase, as airlines and operators have phased out B checks. For airlines and operators to efficiently maintain, repair, and overhaul an aircraft, some B check tasks have been absorbed into A check phases. This helps by reducing aircraft downtime, reducing time maintenance technicians work on the aircraft, improving maintenance scheduling, and implementing better usage of resources such as hangars and test equipment. Aviation maintenance professionals perform B maintenance checks approximately every 6-8 months. It takes about 160-180 labor hours, depending on the aircraft, and can be completed within 1–3 days at an airport hangar. Typical work completed during B checks are tasks such as checking alignment and torquing of the nose landing gear spotlight or inspecting the wheel well hydraulic tubing for condition, corrosion, and fluid leakage. C Checks C and D checks typically fall under “heavy maintenance,” and are much more extensive than the B check. The C check requires an aviation maintenance technician to perform a deep inspection of a majority of the aircraft’s parts. Also, the C maintenance check can often take the aircraft out of service for 1–2 weeks. This type of check often requires an aircraft to stay at a maintenance facility for the necessary space/tools/maintenance technician working hours/materials. Up to 6,000 maintenance hours are typically needed for C checks. Aviation maintenance technicians will perform certain tasks during C checks, such as: examination of structures (load-bearing components on the fuselage and wings) and functions for corrosion and damage checking the operation of the DC bus tie control unit in-depth lubrication of all fittings and cables There are different levels of C checks depending on the type of aircraft, much like how A checks incorporate B check tasks! For example, a schedule might have aviation maintenance technicians performing C1 check tasks on a certain day and then the next day continuing with C2 and so on. D Checks Lastly, the so-called “heavy maintenance visit” occurs every 6-10 years depending on the aircraft. D checks are comprehensive inspections and repairs of the entire aircraft and can mean taking apart the aircraft to inspect for damage and corrosion. The process can take upwards of 30,000 to 50,000 labor hours over a period of four to six weeks. With the entire aircraft stripped down and equipment removed, airlines often decide to refurbish aircrafts’ interiors and upgrade them altogether during D checks. Because of the nature and the cost of a D check, most airlines plan D checks years in advance. Oh, and the cost of the entire process can cost upwards of a few million dollars! There comes a certain point where airlines realize that the cost of repair is more than the actual cost of the aircraft. This usually happens after two or three D checks.
中国大陆民航行业的检修和保养和改装，全球最好。因此，所有二手民航机公务机，来自中国业主的，都比其他来源的，贵上10%左右。
马斯克最近买了架二手公务机，据说，就是中国某公务机租赁公司退役转让的。
corp greed， 政府又deregulation
但也不能排除波音产品设计问题。 今天发现：“波音飞行员座椅的物理移动，带来误触和信号干扰，会造成飞机急剧坠落”
最近那个飞机突然晃动导致多名乘客受伤的事故已经查明，飞行员座椅附近的的一个控制按钮盖子没盖好，空姐给飞行员送食物误碰到按钮，导致飞机突然改变飞行状态。 波音专门下发了一个文件，要求飞行员检查座椅确保按钮盖子扣好。
好像说暂时没排除是不是盒盖松动导致卡到开关，所以还不能说完全跟波音无关
真这个原因的话难道不是设计缺陷？
真行啊，甩锅给空乘。空乘对于她们不熟悉的驾驶舱内按钮肯定躲得远远的。
这可能是因为UA拥有最多的波音飞机吧？
不是这么算的。维修养护肯定是缺失的，ua 只是其中之一。疫情后美国各行业正八经干活的还有吗？汽车业甩锅给缺芯，各类涨价甩给成本供应链，服务业更不用说甩给人员短缺，这都是经济困难时期政治管理的不作为。前线低层工资不涨为保资本不缩水还想着爆利剥削，造成各种消极怠工，无视工作流程政策规定。 各国都受疫情影响，在自救经济的基础上继续（政治）管理系统的运行和调整。而以牺牲民生无视底层前线工作和服务人员的烂操作，包括警察教师医护和政府及其他服务业，断根式的，只此一国
A检是250飞行小时，你可以认为相当于汽车换油，查刹车片机油。C检是4000小时。D检是10000到24000小时之间，大修，换大件，相当于房子装修。
这是怎么发现空姐误碰按钮的？是机场内有录像还是空姐自己坦白从宽？
Not just C&D checks, oil tankers too. China has the advantage of infrastructure, skillset and low labor cost. US airlines are permitted to use certified foreign MRO facilities.
是啊。所以现在不去了
你不知道航空公司是最亏本的资本密集型产业吧，能省.5%，航空公司的CFO半夜要笑醒
US Airways and Southwest fly planes to a maintenance facility in El Salvador. Delta sends planes to Mexico. United uses a shop in China. American still does much of its most intensive maintenance in-house in the U.S., but that is likely to change in the aftermath of the company’s merger with US Airways. 来源：https://www.vanityfair.com/news/2015/11/airplane-maintenance-disturbing-truth
Line Maintenance Checks This type of maintenance is the most routine. Sometimes called post-flight, maintenance pre-flight, service check, and overnight checks, this is the most typical maintenance service performed on aircraft. Line checks require minimal tools and are usually done at the airport gate under the “open sky.”
Line checks happen the most frequently, as they cover basic inspection checks. Commonly, aviation maintenance technicians will inspect things like wheels, brakes, and fluid levels (oil, hydraulics) during line checks.
Performing a line maintenance check ensures an aircraft is airworthy and safe to continue service. Aircraft need line maintenance every 24 to 60 hours of accumulated flight time, but it depends on the operator of the aircraft!
A Checks The next level of checks is known as A checks. The A check is performed approximately every 400-600 flight hours, or every 200–300 flights, depending on aircraft type. A check maintenance is typically done at a hangar and can take a minimum of 10 working hours depending on the services needed. Sometimes, this maintenance is done overnight as to not interrupt the schedule that airlines keep. The frequency of this check varies by aircraft type, the flight cycle count, or the number of hours flown since the last check.
The maintenance work during A checks often covers general inspections of the interior and the aircraft hull for evidence of damage, deformation, corrosion, missing parts. Additionally, it also includes service, engine, and function checks.
Other work performed could entail things such as:
checking emergency lights lubricating nose gear retract actuator checking parking brake accumulator pressure B Checks Next, B checks are often completed during the A check phase, as airlines and operators have phased out B checks. For airlines and operators to efficiently maintain, repair, and overhaul an aircraft, some B check tasks have been absorbed into A check phases. This helps by reducing aircraft downtime, reducing time maintenance technicians work on the aircraft, improving maintenance scheduling, and implementing better usage of resources such as hangars and test equipment.
Aviation maintenance professionals perform B maintenance checks approximately every 6-8 months. It takes about 160-180 labor hours, depending on the aircraft, and can be completed within 1–3 days at an airport hangar.
Typical work completed during B checks are tasks such as checking alignment and torquing of the nose landing gear spotlight or inspecting the wheel well hydraulic tubing for condition, corrosion, and fluid leakage.
C Checks C and D checks typically fall under “heavy maintenance,” and are much more extensive than the B check. The C check requires an aviation maintenance technician to perform a deep inspection of a majority of the aircraft’s parts. Also, the C maintenance check can often take the aircraft out of service for 1–2 weeks.
This type of check often requires an aircraft to stay at a maintenance facility for the necessary space/tools/maintenance technician working hours/materials. Up to 6,000 maintenance hours are typically needed for C checks.
Aviation maintenance technicians will perform certain tasks during C checks, such as:
examination of structures (load-bearing components on the fuselage and wings) and functions for corrosion and damage checking the operation of the DC bus tie control unit in-depth lubrication of all fittings and cables There are different levels of C checks depending on the type of aircraft, much like how A checks incorporate B check tasks! For example, a schedule might have aviation maintenance technicians performing C1 check tasks on a certain day and then the next day continuing with C2 and so on.
D Checks Lastly, the so-called “heavy maintenance visit” occurs every 6-10 years depending on the aircraft. D checks are comprehensive inspections and repairs of the entire aircraft and can mean taking apart the aircraft to inspect for damage and corrosion. The process can take upwards of 30,000 to 50,000 labor hours over a period of four to six weeks.
With the entire aircraft stripped down and equipment removed, airlines often decide to refurbish aircrafts’ interiors and upgrade them altogether during D checks.
Because of the nature and the cost of a D check, most airlines plan D checks years in advance. Oh, and the cost of the entire process can cost upwards of a few million dollars!
There comes a certain point where airlines realize that the cost of repair is more than the actual cost of the aircraft. This usually happens after two or three D checks.
本来就不该把那么重要的按钮放在那么容易按到的地方
还有那个按钮那么重要，难道不应该有secondary safeguard? 比如要求confirm?
而且国内的估计不信任波音的新飞机，买了会自己质检一大遍
我觉得你的信息对楼主的观点是个佐证： AA和UA都是波音机队； AA事故比UA少； —AA维护更好 那么原因呢？ AA还是疫情前的维修机构 UA原来在中国维修，现在不行了 —换维修地点导致UA保养水平下降。
事情其实很明显了 但是某些人有挽尊刚需
无语了，这把人当傻子偏呢，正常空乘，不小心碰到个按钮，肯定吓死了，肯定马上报告机长，还能造成飞机改变飞行状态，好几十人受伤。
主要是最近太多飞了一二十年的老飞机出事儿，这个肯定是维修的问题了。