Afgespeeld
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Situational Awareness
"The perception of the elements in the environment within a volume of time and space, the comprehension of their meaning and the projection of their status in the near future" Mica Endsley 1988
3 levels (or stages) -
- Perception
- Comprehension
- Projection4 Categories of SA -
Geographical
Spatial/Temporal
Systems
Environmental
Types of stress
Physical - noise, vibration, heat, cold and fatigue,
Psychological - mental load, time pressure, perceived time pressure, consequences of events fear, anxiety, uncertainty.
High workload is a form of stress and can be either long term high workload like a 4 sector day in busy airspace, with an inexperienced crew, or short term or even momentary high workload or overload like bad weather on approach.These “clues” can warn of an error chain in progress – a series of events that may lead to an accident. Most accidents involving human error include at least four of these clues. They have been taken from an article written by Douglas Schwartz for FlightSafety International.
-Ambiguity - Information from two or more sources that doesn’t agree.
-Fixation- Focusing on any one thing to the exclusion of everything else.
-Confusion- uncertainty or bafflement about a situation (often accompanied by -anxiety or psychological discomfort).
-Failure to fly the aircraft - Everyone is focused on non-flying activities. (remember the infamous tristar crew that crashed into the everglades because all three of them were fixated on a blown bulb?)
-Failure to look outside… everyone heads down.
-Failure to meet expected checkpoint on flight plan or profile ETA, fuel burn, etc.
-Failure to adhere to SOPs.
-Failure to comply with limitations, minimums, regulatory requirements, etc.
-Failure to resolve discrepancies – contradictory data or personal conflicts.
-Failure to communicate fully and effectively – vague or incomplete statements.
How can improve our situational awareness.
These 10 tips were also part of Douglas Schwartz's article.
1 - Predetermine crew roles for high-workload phases of flight
2 - Develop a plan and assign responsibilities for handling problems and distractions
3 - Encourage input from all crew members, including cabin, ATC, maintenance, dispatch, etc
4 - Rotate your attention from the aircraft to flight path to crew – don’t fixate on one thing
5 - Monitor and evaluate your current status compared to your plan
6 - Project ahead and consider contingencies (for example if you hear aircraft ahead being told to hold)
7 - Focus on the details and scan the big picture
8 - Create visual and/or aural reminders of interrupted tasks (this could be as simple as keeping your finger on a checklist line)
9 - Watch for clues of degraded SA
10 - Speak up when you see SA breaking downLinks
http://www.pacdeff.com/pdfs/AviationSA-Endsley%201999.pdf
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Hydraulic systems can suffer from a number of abnormal situations. Pump low pressure, reservoir overheat, Reservoir low air pressure and reservoir low level. The electric pumps on the blue and yellow systems can also overheat. All of these will lead to the ECAM requesting that you switch off the pump. If this occurs to the green or yellow systems the PTU, if it is available, will transfer power, not fluid, between the systems recovering the affected system. The blue system can not be powered by the PTU. If the PTU is not available or the procedure ask you to turn it off, the failed system will not be powered. This leads to a single system failure.
In the case of a single system failure the aircraft will remain in normal law so all the associated protections are available. Certain flight controls will be affected based on which system has failed but ultimately Aileron, elevator and Rudder control surfaces will remain powered so controlling the aircraft will be conventional. Flaps and or slats will be slow depending on which of the systems has failed, we covered these in the original hydraulics podcast so it maybe worth having a listen again to refresh your memory. Certain spoilers will be unserviceable.
Things start to become more interesting when 2 hydraulic systems fail. When this occurs the Autopilot will be lost so priority must be given to flying the aircraft and stabilising the flight path, the aircraft will also revert to alt law in 2 of the cases, so this, as usual, means direct law once the gear is extended. The ECAM will display LAND ASAP red, this is a timely reminder that you are now operating on a single hydraulic system, why have we lost 2? what happens if we lose the last system? We will cover all 3 cases of Dual hydraulics failure in some detail shortly but lets just broadly go over what you can expect for each case. If you remember these as a guide.
G+B = Handling Problem
G+Y = Braking Problem
B+ Y = As the green system is available this is the least demanding of the 3 scenariosAirbus designed the summary pages to give us all of the information we need to help us during the cruise, approach, landing and if necessary the Go around. in the FCOM Pro-ABN-01- Use of Summaries section, more background information is provided. it states that the summaries are QRH procedures created to help the flight crew to perform actions. In ANY case the flight crew should apply the ECAM first, this includes the STATUS page. This is an important point, it is all too easy in a high workload situation to divert our attention to performance calculations and other tasks before completing the ECAM. The ECAM’s for dual hydraulics are not actually that long and the status page will give you valuable information as to the state of the aircraft increasing your situational awareness.
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This week we take a look at engine issues at various stages of flight, what to look out for and how to handle these scenarios
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This week Matt & Andy look at FMGC failures and their consequences.
There's little information in the manuals so they both take us though the effects of these failues and some of the issues that can be faced.
