| Recurring |
one_organization, multiple_organization |
(a) The software failure incident related to the Asiana flight crash into San Francisco highlighted issues with the design of the Boeing 777's automation logic. Asiana faulted its crew for failing to notice that the airplane was flying too slowly, but also blamed "inconsistencies in the aircraft’s automation logic" which led to the unexpected disabling of airspeed protection without adequate warning to the flight crew [25292].
(b) The article mentions that in 2010, when another Boeing plane with a similar auto-throttle, the 787, was being certified by the Federal Aviation Administration (F.A.A.), concerns were raised about the way the throttles went into sleep mode. Boeing declined to make a change and agreed with the F.A.A. to put a warning into the pilot manuals. After the Asiana crash, test pilots from the F.A.A. and the airline had severe difficulties flying the approach that air traffic controllers had given the Asiana flight, indicating potential issues with the software or design that could affect multiple organizations [25292]. |
| Phase (Design/Operation) |
design, operation |
(a) The software failure incident in the Asiana flight crash into San Francisco was attributed to design issues related to the aircraft's automation logic. Asiana faulted the crew for failing to notice that the airplane was flying too slowly, but also blamed "inconsistencies in the aircraft’s automation logic" which led to the unexpected disabling of airspeed protection without adequate warning to the flight crew [25292].
(b) The software failure incident can also be linked to operational factors. The crew believed that the auto-throttle system would manipulate the engines to maintain the plane's airspeed, but due to a quirk in the autopilot and auto-throttle systems, the auto-throttle went into sleep mode. This operational misunderstanding, combined with the crew's manual adjustments to the throttles, contributed to the failure during the landing approach [25292]. |
| Boundary (Internal/External) |
within_system |
(a) within_system: The software failure incident in the Asiana flight crash into San Francisco was primarily attributed to issues within the system. Asiana faulted its crew for failing to notice that the airplane was flying too slowly, but also blamed "inconsistencies in the aircraft’s automation logic" which led to the unexpected disabling of airspeed protection without adequate warning to the flight crew [25292]. The auto-throttle system, a part of the aircraft's automation logic, went into sleep mode due to a quirk in the autopilot and auto-throttle systems, contributing to the failure [25292]. The crew's lack of training on certain characteristics of the 777, such as the "flitch trap," also played a role in the software-related failure incident [25292]. |
| Nature (Human/Non-human) |
non-human_actions, human_actions |
(a) The software failure incident in the Asiana flight crash into San Francisco was attributed to non-human actions. Asiana faulted its crew for failing to notice that the airplane was flying too slowly, but also blamed "inconsistencies in the aircraft’s automation logic" and bad software design that led to the unexpected disabling of airspeed protection without adequate warning to the flight crew [25292].
(b) Human actions were also identified as contributing factors in the software failure incident. The crew believed that the auto-throttle system would manipulate the engines to maintain the plane's airspeed, but due to a quirk in the autopilot and auto-throttle systems, and because the crew manually adjusted the throttles at one point, the auto-throttle went into sleep mode. Additionally, the pilots were not trained on certain characteristics of the Boeing 777, including the "flitch trap" issue, which was a setup for the unwary [25292]. |
| Dimension (Hardware/Software) |
hardware, software |
(a) The software failure incident related to hardware can be seen in the article where it mentions that bad software design led to the unexpected disabling of airspeed protection without adequate warning to the flight crew, and a system to warn the crew of low airspeed did not sound soon enough [25292]. This indicates a failure originating in the software design that affected the hardware system of the aircraft.
(b) The software failure incident related to software itself is evident in the article where it discusses the quirk in two tightly linked systems, the autopilot, and the auto-throttle, which led to the auto-throttle going into sleep mode due to a manual adjustment by the crew. This software-related issue caused a critical failure in the system, contributing to the crash [25292]. |
| Objective (Malicious/Non-malicious) |
non-malicious |
(a) The software failure incident related to the Asiana flight crash into San Francisco was non-malicious. The incident was attributed to bad software design that led to the unexpected disabling of airspeed protection without adequate warning to the flight crew. Asiana faulted its crew for failing to notice that the airplane was flying far too slowly to stay in the air, and also blamed inconsistencies in the aircraft's automation logic. The crew believed that an auto-throttle would manipulate the engines to keep the plane's airspeed in the safe landing range, but due to a quirk in the autopilot and auto-throttle systems, the auto-throttle had gone into sleep mode, leading to the crash [25292]. |
| Intent (Poor/Accidental Decisions) |
poor_decisions, accidental_decisions |
(a) The software failure incident related to the Asiana flight into San Francisco was primarily due to poor decisions. Asiana faulted its crew for failing to notice that the airplane was flying too slowly, but also blamed "inconsistencies in the aircraft’s automation logic" which led to the unexpected disabling of airspeed protection without adequate warning to the flight crew [25292]. Additionally, the crew believed that the auto-throttle system would manipulate the engines to maintain the plane's airspeed, but due to a quirk in the autopilot and auto-throttle systems, the auto-throttle went into sleep mode, leaving the crew with no protection against aerodynamic stall. This characteristic was known as the "flitch trap" and the crew had not been adequately trained on this aspect of the 777 aircraft [25292]. |
| Capability (Incompetence/Accidental) |
development_incompetence |
(a) The software failure incident related to development incompetence is evident in the Asiana flight crash into San Francisco. Asiana faulted its crew for failing to notice that the airplane was flying too slowly, but also blamed "inconsistencies in the aircraft’s automation logic" which led to the unexpected disabling of airspeed protection without adequate warning to the flight crew [25292].
(b) The software failure incident related to accidental factors is seen in the quirk in the autopilot and auto-throttle systems on the Boeing 777, which led to the auto-throttle going into sleep mode due to a manual adjustment by the crew. This characteristic, known as the "flitch trap," was not adequately communicated to the pilots, leading to a situation where there was no protection against aerodynamic stall [25292]. |
| Duration |
temporary |
The software failure incident related to the Asiana flight crash into San Francisco was temporary. The incident was attributed to contributing factors introduced by certain circumstances, such as bad software design that led to the unexpected disabling of airspeed protection without adequate warning to the flight crew [25292]. Additionally, the crew's misunderstanding of the auto-throttle system and the quirk in the autopilot and auto-throttle systems contributed to the temporary software failure incident. |
| Behaviour |
crash, omission, timing, value, other |
(a) The software failure incident in the Asiana flight crash into San Francisco was related to a crash. The incident involved the unexpected disabling of airspeed protection without adequate warning to the flight crew, leading to the crash [25292].
(b) The software failure incident also involved an omission. The system failed to provide a timely warning to the crew of low airspeed, which contributed to the crash [25292].
(c) The timing of the software failure incident was also a factor. The system did not sound the warning of low airspeed soon enough, impacting the crew's ability to react in a timely manner [25292].
(d) The software failure incident was related to a value failure. The system's design flaw led to the disabling of airspeed protection, causing the system to perform its intended function incorrectly [25292].
(e) The software failure incident did not exhibit a byzantine behavior as described in the articles.
(f) The other behavior exhibited by the software failure incident was related to the system's interaction with other systems. The incident involved a quirk in the interaction between the autopilot and the auto-throttle systems, leading to the auto-throttle going into sleep mode, which was not anticipated by the crew [25292]. |