8 The Unexpected

8 The Unexpected

8.1. General

8.1.1. Missed Approach

8.1.2. Standard  Terms

8.1.3 Reasons for Going Around

8.1.4. The Procedure

8.1.5 Practical Examples

8.2 Loss of Radar Contact

8.2.1. VATSIM Limitations and Implications

8.2.2. How to Handle

8.2.3. Phraseology

8.3 Communication Failure

8.3.1 Light Signals

8.3.2 Procedure Approach

8.3.3 ATC Action

8.4 Emergencies

8.4.1 Example of  Urgency Messages

8.4.2 Example of Distress Messages

8.4.3 Contingencies

8.4.4. ATC action

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8. The Unexpected General  

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8.1.1. Missed Approach [SS]

A go-around, overshoot or missed approach is an aborted landing of an aircraft which is on final approach.

Missed Approach procedures differ from airport to airport and the procedure to be flown can be found on the respective approach plates. In general in VATSIM, ATC usually tends to give all aircraft the same command on a Missed Approach being something similar to:

EX123 Fly runway heading to 3000ft, stand by for vectors.

Whilst one could argue that there really is nothing wrong with this approach to things, as it would allow the pilot to climb on the runway heading giving him or her the time to read the published procedure, the fact is that it is not really correct as there are specific Missed Approach procedures in use at various fields, which call for different instructions.

The Fly Runway heading in VATSIM is being used generally for a number of reasons.

• Easy to remember.
• Gives the ATC flexibility in deciding if the approach will be a left or a right had turn
• Easy for pilots.

However, as most of us know, the increasingly sophisticated Add On packages available means that a growing number of us are able to follow the correct Missed Approach procedure which – you have guessed it – is not a runway heading.

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8.1.2 Standard Terms

Let us look at the standard phrases and terms that exist in respect to missed approaches, there are more than one may think.

• Missed Approach (MA): Other expression for Missed Approach Segment.

• Missed Approach Point (MAPt): This designates the point during a non-precision instrument approach that signals the termination of the final approach and the start of the missed approach segment, this point may be:

• The intersection of an electronic glide path with a decision height.
• A NAVAID located at the field
• A suitable fix, for example a DME
• A specified distance beyond the NAVAID or final approach fix, (FAF), not to be exceeded.
• Missed Approach Holding Waypoint (MAHWP) the waypoint designated in the missed approach segment of an instrument approach procedure to which the aircraft will automatically fly and upon reaching this position, enter a specified holding pattern.

• Missed Approach procedure: The procedure that has to be followed after an instrument approach procedure, if, for any reason, a landing can not be effected. it normally occurs:

• When the Aircraft has descended to the decision height (DH) or to the minimum descent altitude (MDA) and reached the missed approach point or waypoint and has not established the required visual reference to land.

• When the aircraft is directed by ATC to pull up or to Go Around.

• Missed Approach Segment: The Part of an instrument approach procedure between the missed approach point, (MAPt), the missed approach waypoint (MAWP) or the point of arrival at Decision Height, and the specified missed approach NAVAID, intersection, fix  or waypoint, as appropriate, at the minimum IFR altitude. It is in this part of the approach procedure that the aircraft climbs and returns to the en-route structure or is directed for holding or subsequent approach.

• The route of flight and altitudes are shown on instrument approach charts.

• Missed Approach Turning Waypoint: (MATWP) The waypoint designated in the missed approach segment of an instrument approach procedure to which the aircraft will automatically fly en  route to the specified missed approach holding waypoint.(MAHWP)

• Missed Approach Waypoint (MAWP) The waypoint on the final approach course that signifies the termination of the final approach segment and the start of the missed approach segment.

• Overshoot: The phase of a flight wherein a landing approach of an  aircraft is not continued to touchdown (also called Go-Around)

8.1.3 Reasons for Go Around

The go-around procedure may be initiated either by ATC or by the captain of the aircraft.

The air traffic controller will instruct the pilot to go around if there is an aircraft, vehicle or object on the runway. or there are other hazards that could bring the aircraft into a dangerous situation unless instructed to go around.  The captain will decide to go around if the aircraft is not lined up or configured properly for the approach, a landing aircraft has not cleared the runway, no landing clearance was issued, the runway is not visible by the time the aircraft reaches the decision height because of low visibility, or if other dangerous meteorological conditions are experienced on final approach.

A go-around in itself does not constitute any sort of emergency.

In other words:

An aircraft shall be instructed by ATC to carry out a missed approach in any of the following cases:

• On Instructions from TWR ATC if no landing clearance is received at the MAWP or DH
• On Instructions from TWR ATC if the aircraft appears to be wrongly positioned on final approach.
• On Instructions from TWR ATC if the aircraft is not visible on radar during final approach.
• On instructions from TWR ATC if the landing runway is not cleared by other aircraft’s.

An Aircraft can initiate a Go Around on his own if:

• The pilot arrives at DH and is still in the clouds and does not have any visual references
• The pilot has not received Landing Clearance at the DH  In this situation actually the pilot HAS to go around except if the pilot decides that going around would bring the aircraft into a more dangerous situation than landing (for example if low on fuel)
• The pilot deems that to continue the approach would endanger the aircraft.

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8.1.4. The Procedure   

When the captain is instructed, or decides himself to go around, he will apply full power to the engines, adopt an appropriate climb attitude and airspeed, retract landing gear, retract flaps as necessary and follow the published missed approach procedure (a set path to follow in the event of a go-around) or the instructions of the air traffic controller.

EX123 climb to 3000ft on runway heading.

This is wrong; there is no need to tell the pilot to climb! The pilot is already climbing as per the prescribed Missed Approach Procedures.

The correct command should be something like this

EX123 execute missed approach for runway xx
or
EX123 continue missed approach, stand by for vectors.
or
EX123 Roger

However many pilots on VATSIM are not prepared for a possible missed approach and do know the missed approach procedures. ATC should ask the pilot whether he is able to follow standard missed approach. If he does not then vectors similar to the example above are given.

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8.1.5. Practical Examples

Choose any local approach chart from your VACC and get familiar with the missed approach procedures. The example below illustrates a simple missed approach procedure and the impact this may have on ATC.

Runway 27: The aircraft continues on a track of 267° to 3000ft and upon reaching 3000 feet (more or less 2nm from GE) the pilot would turn right toward the LO NDB on 314 and would enter the prescribed hold at LO.

The above procedure should happen automatically and unless ATC gives a different command.

EX123, going around
Twr “somewhere” Copy Exair123 execute missed approach rwy 27, report inbound LO

EX123, inbound LO
Twr “somewhere” Exair123 leave LO on Heading 110, maintain 3000ft vectors for LOC runway 27

 From there onwards it is only a matter of vectoring to bring the aircraft back to the LOC as usual.

Different Fields use different procedures and these procedures again are different depending on  the type of aircraft involved in the process. The main thing to bear in mind is that the missed  approach procedure does involve a prescribed hold unless ATC instructs the pilot differently.

8.2. Loss of Radar Contact [C+]

There are two main methods to control traffic: Radar and Non-Radar.

Radar is used to accurately determine each aircraft’s position in order to separate and sequence traffic.

Non-radar uses time and distance to create blocks of protected airspace for each aircraft along its route.

In real-life, both methods are normally used together according to the situation and equipment limitations, as Radar coverage may not always be 100%. Especially over the ocean or in remote areas.

Procedural Approaches are normally used in NON RADAR environment; hence they will hardly (if ever) be of importance for us as VATSIM is a 100% radar environment

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8.2.1. Vatsim Limitations and Implications

However, having said this, we can if we so want to; simulate a Non Radar environment. Such a simulation may in fact be simulated during a Controller Practical Test

In earlier versions of the software we use it was possible for a pilot to disconnect from the servers whilst maintaining voice contact as the programs used were stand alone applications. With voice now being integrated the moment a pilot disconnects he or she is totally gone. The only way to simulate a loss of radar contact is:

In practice (if this situation should occur) then the most likely scenario will be the pilots continuing on line but in Standby mode.

Assuming however that a non radar or radar loss occurs then you as ATC will have to reply mainly on the pilot being able to maintain non-radar separation minima: which is the minimum (visual) separation to be maintained by approaching aircraft following a published procedure approach.

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8.2.2. How to Handle

Very straight forward, an aircraft is with you on voice and radar and cleared inbound your field the aircraft will be told to somehow do a magic disappearance trick and you as ATC loose the vital data.

However the aircraft is still there and is still moving at the same speed/heading and FL as when he disappeared from the scope and he is still with you on voice.