|Last Updated||11/24/2020 22:32
by Skylar Hutter
There are many concepts a tower controller needs to learn in order to be efficient and proficient at his/her position. A lot of these concepts are great to know in theory, but must be put into practice in order to best control the position. As VATSIM controllers, we provide a service to the virtual flying community which is expected to be efficient and professional. For this reason, we should review one of the core and most important concepts: Same Runway Separation (SRS)
There are 3 types of same runway separation: General, Category, and Wake Turbulence, with special wake turbulence requirements for intersection departures.
General Separation - Separate a departing aircraft from a preceding departing or arriving aircraft using the same runway by ensuring that it does not begin takeoff roll until (1) the other aircraft has departed and crossed the runway end or turned to avert any conflict or (2) A preceding landing aircraft is clear of the runway.
Category Separation - Category separation is simply separating aircraft by category alone. There are 3 categories of aircraft: Category I, Category II, and Category III
Note - Categories set forth in 3-9-6 of the 7110.65Y are for SRS only and should not be confused with the J, T, and P categories as outlined in SOPs 102 and 103. The categories mentioned in these SOPs are used when determining items such as initial altitudes and departure headings, therefore should not be used interchangeably with SRS categories.
Category separation is applied by separating aircraft by a specified number of feet. This is the lateral distance, not vertical. This distance must exist by the time the second aircraft starts its takeoff roll. Separation is as follows:
Wake Turbulence Separation - Wake Turbulence Separation is separating successive departures based on wake turbulence. There are 4 aircraft groups for the purpose of wake turbulence. These categories are based on the maximum takeoff weight of the aircraft, not the actual weight.
Wake turbulence separation may be applied in two different ways: In minutes or in miles.
Because PDX and SEA are radar towers, we may use miles, which is much quicker than minutes, but it is still important to know both. There are, however, certain instances where you can only use time for wake turbulence separation (mentioned and required for intersection departures).
Miles (preferred for PDX and SEA):
Wake Turbulence Separation (Intersection Departures) - Wake Turbulence Separation for Intersection Departures is separation applied based on aircraft departing from an intersection behind another aircraft which departed at the full length of a runway.
*Note - These first two time intervals may be waived upon pilot request. A request for takeoff is not a waiver request; such requests must be made separately.
Note - Any of these time intervals may be waived if:
Note - Aircraft conducting touch-and-go and stop-and-go operations are considered to be departing from an intersection.