SKYbrary Highlights

[Jonas Kuster]

This is a a loose collection of SKYbrary articles and animation videos. Feel free to contribute with links to SKYbrary articles you find helpful. SKYbrary provides a large number of interesting articles about aviation topics. It's a perfect platform to expand your knowledge.

[Jonas Kuster]

TCAS RA Not Followed | SKYbrary Aviation Safety

[Jonas Kuster]

Did you know that RVSM airspace exists only between FL290 and FL410, if declared?
And are you aware what separation minima would apply if there was no RVSM airspace?

Thankfully, RVSM airspace is implemented in many regions, including entire Europe.

https://skybrary.aero/articles/reduc...on-minima-rvsm

[Jonas Kuster]

Have you ever experienced a sudden need for a go around and were not sufficiently prepared/briefed? Maybe it was not obvious that a missed approach might be needed and your mental picture didn't take into consideration this scenario?
Such situations can be overwhelming, especially if you are flying/managing a complex aircraft solo. But even real-life situations can take you by surprise, as it did for a French Bee crew on an approach during nice weather in Paris Orly.

Read more about it in the following article: A359, vicinity Paris Orly France, 2020 | SKYbrary Aviation Safety

[Jonas Kuster]

Two very interesting report from Abu Dhabi (June 2020) and Paris (March 2022) from occurrences involving incorrect altimeter setting during an LNAV/VNAV RNP Approach.

B78X, vicinity Abu Dhabi UAE, 2020 | SKYbrary Aviation Safety
A320, vicinity Paris CDG France, 2022 | SKYbrary Aviation Safety

The phraseology proposal for ATC in such a situation would be: (call sign), LOW ALTITUDE WARNING, CHECK YOUR ALTITUDE IMMEDIATELY, QNH IS (number) [(units)].

Compared to the reaction from the controllers in Paris in the abovementioned case, this will immediately draw the pilots attention to the issue observed by ATC and the relevant parameter (QNH) to be checked. In abnormal situations, ATC should only report the observed discrepancy (which leads to a call) to pilots. This will provide the best clues to a flight crew on why ATC is actually initiating a call and result in more structured reaction by the flight crew.

[Jonas Kuster]

Single runway operations with mixed arrivals and departures requires a continuously updated mental picture. Unambiguous instructions and traffic information where necessary are key elements to successfully execute a plan. Keep in mind that pilots may not be aware of relevant depended traffic resulting in a certain urge to follow them. ATC should use appropriate phraseology where applicable. Also consider a revision of your plan, and correct accordingly as early as possible. Feeling uncomfortable is a first indicator to give yourself some space in order to provide safe and efficient service. If it's getting "tight", adapt your working style and reduce the pressure by adding additional (safety) margins.

The following article describes a situation in Malaga in 2019 involving a landing very close behind a departing aircraft. And according to the report, it wasn't the only occurrence. You might have found yourself in a similar situation during a session on VATSIM (when controlling LSGG).
The identified contributing factors are equally valid for real-life and simulation scenarios.

B738 / B738, Malaga Spain, 2019 | SKYbrary Aviation Safety

[Jonas Kuster]

A good example to demonstrate the importance to review and verify data after it has been entered into the FMC/FMS. While on VATSIM the main issues are increased workload for ATC and possible conflicts with other pilots, actual terrain clearance is vital in real life. Fortunately, the event explained in this article did not cause any harm to people.
The most important contributory factor was probably that "The SID course and the first active waypoint were not verified". Especially the initial part of a SID needs to be verified at all times. Modifications of terminal procedures (SID/STAR/Transitions) is usually limited or even prohibited, unless an amended clearance by ATC is received.

B748, vicinity Hong Kong China, 2017 | SKYbrary Aviation Safety

[Jonas Kuster]

In the light of the recently published MSFS scenery for Bern, have a look at the following explanation video about the risks associated with the separation of arrival and departure aircraft involving a circling approach.

Separation of arrival and departure aircraft during circling approach (SKYclip) | SKYbrary Aviation Safety

Bern has defined patterns for circling approaches, which reduce the risk of uncertainties. However, the majority of points raised in the video is also relevant for Bern, as they are for other airports providing circling approaches.

[Jonas Kuster]

Low Level Go Arounds are a risk at busy airports, especially if the same runway is used for arrivals and departures. The following video shows a possible scenario which fits perfectly LSGG Geneva airport. A number of recommendations and learning are provided to avoid such situations.

Low Level Go Around (SKYclip) | SKYbrary Aviation Safety

As the landing phase requires high workload in the cockpit and for the TWR controller to monitor the situation, a state of uncertainty (has clearance been issued already?) or expectation bias (assuming the clearance has been issued) regarding the provision of the landing clearance could arise. Due due the time criticality, landings without a clearance may be difficult to detect and solve last second. The following article lists factors, which may contribute to such situations.

Landing without Clearance – Precursors and Defences | SKYbrary Aviation Safety

Safety barriers for controllers include strip marking (to record issued landing clearances). While the controller client EuroScope by default does not provide such an option, our plugin EasyTag adds such a functionality in the form of a checkbox integrated in the Arrival List / ADC Sector List. This helps the controller to keep track of provided landing clearances.

[Jonas Kuster]

Reasons for unstablisied approaches are diverse. Contributing factors not only exist from the pilot side, but also ATC. Both have different options to facilitate an unstabilised approach, directly or induced. But both have also the possibility to recognise the issue and support a resolution of the situation, which is a go around in the vast majority of cases.
The pilots responsibility is closely linked to standard operating procedures including stabilisation criteria, mutual monitoring and call outs. When flying solo on VATSIM, self-monitoring and flying at the same time may be demanding, especially in a phase of flight which causes naturally a workload.
The controllers role to monitor approaches becomes even more important in this case. Lateral and vertical evolution of the flight path, but also pilot readbacks and execution of instructed maneouveres provide a comprehensive idea of a pilots stress and workload. While an initial reaction should only be to alert the pilot of observed deviations, it might also become necessary to instruct an abortion of the approach.
A common denominator of unstabilised approaches is an unprepared or rushed attempt to land. Therefore, sufficient time should be considered to prepare and guide an approach. Higher priority shall be given to a stabilised approach rather than a super-efficient and short flight trajectory. The currency (regular training) is also an important factor influecing the efficiency and completness of your workflows and manipulations. Experience certainly helps, but can never replace routine.

Pilots:

• Prepare an approach in due time
• Ask for support / additional track miles if not yet ready for an approach
• Establish a number of criteria which support a stabilised approach
• Initiate a go around if criteria are not met

Controllers:

• Don't unnecessarily rush pilots for an approach
• Consider the total energy management (altitude & speed (& weight) vs. distance from threshold)
• Aim for a clean intercept of the LOC and GP (do you know the criteria?)
• Monitor approaches closely and keep them on your frequency if you doubt that a successful landing will be completed

Here are two incident reports unstabilised approaches:

• A318, vicinity Paris Orly France, 2020
• A359, vicinity Frankfurt Germany, 2020

[Jonas Kuster]

Separation loss can suddenly become critial in the departure and approach phase, namely in holdings. The incident northwest of Surabaya Indonesia involving two aircraft approaching the same holding is an exemplary situation where reduced attention to other traffic communications and a misselected altitude resulted in a TCAS RA.

A320 / B739, en-route, northwest of Surabaya Indonesia, 2018 | SKYbrary Aviation Safety

As aircraft on the network are usually operated by one pilot only, similar situations may also occur online. Therefore a high level of attention is required when operating in dense airspace, approach sectors and holdings. Clearances are often issued in order to keep only the minimum required separation. Consequently there little to no room for errors.
It is also advised that pilots pay attention to communications between the controller and other pilots in order to raise situational awareness. If you realise what other traffic is doing, you might also notice conflicting or misinterpreted clearances, prompting you to check your own flight path again. If you are in doubt or wish to reconfirm a clearance or parts of it, don't hesitate to ask the controller to "say again".

[Jonas Kuster]

This case of a runway incursion of a departing aircraft while another one was landing on the same runway shows how important standard phraselogy can be. And how easily an instruction can be misinterpreted.

A319 / B738, Cheongju South Korea, 2016 | SKYbrary Aviation Safety

These key takeaways are also valid for the VATSIM environment:

• The use of standard phraseology is intended to avoid misunderstandings
• If an instruction seems ambigous, don't hesitate to ask for clarification ("confirm ...", "say again ...")
• A clearance limit is an effective measure contributing to safe operations
• Understanding the different ATC stations roles and responsibility helps a pilot to increase situational awareness, and thus contributing to safe operations
• Airports with low traffic volumes not necessarily reduce the risk of runway incursions