Reduced Vertical Separation Minima (RVSM)
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
Missing FMC input verification leads to terrain proximity warning
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
Separation of arrival and departure aircraft during circling approach
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.
Landing Clearance / Go Around
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.
Monitoring of communications with other traffic
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".
The importance of using standard phraseology
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