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Why is it a useful technique?

Helps to find the right quantity of traffic, because…

Too little traffic?
Too much traffic?

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What has historically been wrong during VATSIM events?

Almost always a problem of too much traffic.

Even if the landing rate is high, the picture often lacks ‘familiarity’ or a sense of being ‘standard’.

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Is this just a bit overkill for VATSIM?

Enables proper forward planning
More manageable frequency
Essential for busy events
More enjoyable

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The Prerequisites

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Core Final Approach Spacings

Spacing	Applicability
2 NM	Diagonal radar separation for aircraft on dependent parallel approaches
2.5 NM	Absolute minimum final approach separation for use when: Offered by the tower There is a strong (15kt+) headwind component Braking action is good Cloud base is high enough to apply RSIVA beyond 6.5 NM
3 NM	Standard (reduced) minimum radar separation
3.5 NM	RECAT-EU – Category B behind a Category B
4 NM	RECAT-EU – Category D behind a Category B

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Compression

What do we mean by compression?
What are the risks posed?
What does this mean for final approach spacing?

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The Target

Aim for 4 NM in ‘normal’ conditions
… except where the required RECAT-EU spacing is 4 NM or greater

e.g. A320 behind a B77W, FIN should aim for 5 NM 🡪�compressing to no less than 4 NM

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Using this as INT

If we know that FIN will be aiming for up to 5 NM…

… as INT, we will therefore be counting in 5s A LOT!

‘5 mile plan’
Variation is to be expected – this technique is for planning

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Standard Patterns

What have you been told about ‘standard vectoring patterns’?
Why do we tell VATSIM controllers this?

What if we told you they are in fact useful…?

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Standard Patterns – Westerlies

Hold	Standard Pattern Distance (NM)
BIG	30 (or 35*)
LAM / BNN / OCK	35 (or 30*)

* Depending on the wind and vectoring, the ‘standard pattern’ can be made to be 30 or 35 miles from any hold.

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Standard Patterns – Easterlies

Hold	Standard Pattern Distance (NM)
BNN / OCK	30
BIG	50
LAM	55

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Variations

Delay Vectors	+ 5-10 miles
Orbit (360°)	+ 10 miles
Hold	+ 15-20 miles

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The Technique

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A Westerly Example

Aircraft A
Aircraft B
Aircraft C
Aircraft D
Aircraft E
Aircraft F

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A Westerly Example

A	Who is at...	20 miles from touchdown?
B	Who is at 20+5=	25 miles?
C	Who is at 25+5=	30 miles?
D	Who is at 30+5=	35 miles?
E	Who is at 35+5=	40 miles?
F	Who is at 40+5=	45 miles?
G	Who could be at 45+5=	50 miles?
H	What’s the picture beyond that?

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The Technique

Start at an aircraft near 20 miles, and work backwards!

How does the process change for Easterlies?

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Descending Aircraft

From MSL to FIN

Do not ❌ descend aircraft below MSL until they are headed towards the final approach. Why?
Go straight to 4000 feet unless there is a specific reason not to. Why?

Facilitating CDAs

When to issue track mileage?
What if an aircraft isn’t at exactly 20 miles from touchdown?
Count backwards from an aircraft you know the miles for.

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Being Responsive

An iterative process

Be proactive AND reactive

What if FIN is…

establishing aircraft at less than 12 DME?
establishing aircraft out at 16-17 DME?

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The ‘Master’ Director

Establish a landing order
INTs speak the most
Do not try to ‘control by proxy’

“take your aircraft off Ockham now heading 075”

“your Speedbird 33CE is behind the Jordanian 36C leaving LAM this time around”

“order is SHT9Z, BAW45EM, SWR62A, BAW43HA, AFR15NP, KLM1009”

“my two heavies are coming off, then you take two mediums”

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Adjustments

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Delaying Tactics

How many miles does an orbit add?
What if we want to add a little less than this, or an aircraft isn’t in a good place for an orbit?

“Speed control serves to _________ separation, rather than _________”

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Whiteboard Activity!

Link: https://www.twiddla.com/

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Accounting for Wind

Scenario 1 – Strong Headwind on Final Approach

What does this mean for the landing rate?
How will an aircraft’s ground speed change throughout the approach?
‘Skipping’ an aircraft vs. Adjusting the assumed mileage

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Accounting for Wind

Scenario 2 – Strong South/Southwesterly Wind

How will an aircraft’s ground speed change throughout the approach?
Does this differ depending on the side of the approach?
When, and by who, will aircraft likely be instructed to reduce to 180 knots?
How could we use vertical separation to our advantage?

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Questions?

What are the assumptions underpinning the 5 mile technique?
What is the assumed mileage from each hold for each configuration?
When do FIN need to be transferred the aircraft?
How is this a difficult technique to apply on VATSIM?

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With Thanks

To Tim Clark & James Yuen for their help in producing the ‘Counting the Miles’ guide for Heathrow

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Feedback

Thanks for attending!

To feedback on this particular seminar: vats.im/ops-seminar-feedback

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