Lesson 1

3−9−6. SAME RUNWAY SEPARATION 

CATEGORY I - Small single−engine propeller driven aircraft weighing 12,500 lbs. or less, and all helicopters

CATEGORY II - Small twin−engine propeller driven aircraft weighing 12,500 lbs. or less. 

CATEGORY III - All other aircraft. 

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: 

a. The other aircraft has departed and crossed the runway end or turned to avert any conflict. (See FIG 3−9−1.) If you can determine distances by reference to suitable landmarks, the other aircraft needs only be airborne if the following minimum distance exists between aircraft: 

1. When only Category I aircraft are involved− 3,000 feet. 

2. When a Category I aircraft is preceded by a Category II aircraft− 3,000 feet. 

3. When either the succeeding or both are Category II aircraft− 4,500 feet. 

4. When either is a Category III aircraft− 6,000 feet. 

5. When the succeeding aircraft is a helicopter, visual separation may be applied in lieu of using distance minima. 

b. A preceding landing aircraft is clear of the runway. (See FIG 3−9−3.)

EXAMPLE #1 - Two B738s are holding short of a runway. The first B738 needs to be airborne and past 6,000ft down the runway before the second B738 can begin its takeoff roll.

EXAMPLE #2 - A Piper Seminole is #1 (Category II) and a Cessna 172 is #2 (Category I) short of a runway. The Seminole needs to be airborne and past 3,000ft down the runway before the C172 can begin its takeoff roll.

EXAMPLE #3 - An A321 is holding short of a runway for an arriving C172. The A321 cannot begin its takeoff roll until the C172 has cleared the runway.

FULL LENGTH DEPARTURES (3−9−7.)

d. Do not issue clearances to a small aircraft to line up and wait on the same runway behind a departing super or heavy aircraft to apply the necessary intervals. 

e. The minima in Paragraph 5−5−4, Minima, subparagraph g, may be applied in lieu of the time interval requirements in subparagraphs f, g, and h. When Paragraph 5−5−4, Minima, is applied, ensure that the appropriate radar separation exists at or prior to the time an aircraft becomes airborne. 

NOTE - 2. Takeoff clearance to the following aircraft should not be issued until the time interval has passed after the preceding aircraft begins takeoff roll. 

f. Separate aircraft taking off from the same runway or a parallel runway separated by less than 2,500 feet:

1. Heavy, large, or small behind super − 3 minutes. 

2. Heavy, large, or small behind heavy − 2 minutes.

g. Separate a small behind a B757 aircraft by 2 minutes when departing: 

1. The same runway or a parallel runway separated by less than 700 feet.

2. A parallel runway separated by 700 feet or more if projected flight paths will cross.

h. Separate aircraft departing from a parallel runway separated by 2,500 feet or more if projected flight paths will cross:

1. Heavy, large, or small behind super − 3 minutes. 

2. Heavy, large, or small behind heavy − 2 minutes. 

l. Do not approve pilot requests to deviate from the required intervals contained in subparagraphs f through h. 

n. Inform aircraft when it is necessary to hold in order to provide the required time interval. 

PHRASEOLOGY− HOLD FOR WAKE TURBULENCE. 

EXAMPLE #1 - A B744 is in front of a B738 short of a runway. A 2 minute timer shall be started when the B744 stats its takeoff roll. The B738 cannot be cleared for takeoff until the time has expired. The B738 pilot cannot waive this time.

EXAMPLE #2 - You are working OKC tower. A C172 is short of runway 17R and an A388 short of 17L. No wake turbulence separation is required, and simultaneous takeoffs authorized, so long as flight paths do not cross. (Runways separated by more than 2,500ft).

EXAMPLE #3 - A B738 is in front of a C172 short of a runway. No wake turbulence separation is required. (A wake turbulence cautionary advisory is highly encouraged).

3−9−7. WAKE TURBULENCE SEPARATION FOR INTERSECTION DEPARTURES 

a. Apply the following wake turbulence criteria for intersection departures:

1. Separate a small aircraft weighing 12,500 lbs. or less taking off from an intersection on the same runway (same or opposite direction takeoff) behind a departing small aircraft weighing more than 12,500 lbs. by ensuring that the aircraft does not start takeoff roll until at least 3 minutes after the preceding aircraft has taken off. 

2. Separate a small aircraft taking off from an intersection on the same runway (same or opposite direction takeoff) behind a departing large aircraft (except B757) by ensuring that the aircraft does not start takeoff roll until at least 3 minutes after the preceding aircraft has taken off. 

3. Separate a small aircraft taking off from an intersection (same or opposite direction takeoff) behind a preceding departing B757 aircraft by ensuring that the small aircraft does not start takeoff roll until at least 3 minutes after the B757 has taken off from: 

(a) The same runway or a parallel runway separated by less than 700 feet. 

(b) Parallel runways separated by 700 feet or more, or parallel runways separated by 700 feet or more with the runway thresholds offset by 500 feet or more, if projected flight paths will cross. 

4. Separate aircraft departing from an intersection on the same runway (same or opposite direction takeoff), parallel runways separated by less than 2,500 feet, and parallel runways separated by less than 2,500 feet with the runway thresholds offset by 500 feet or more, by ensuring that the aircraft does not start take-off roll until the following intervals exist after the preceding aircraft has taken off: 

(a) Heavy, large, or small behind super - 4 minutes. 

(b) Heavy, large, or small behind heavy - 3 minutes. 

NOTE− Apply Para 3−9−6, Same Runway Separation, subpara f to parallel runways separated by less than 2,500 feet with runway thresholds offset by less than 500 feet. 

5. Inform aircraft when it is necessary to hold in order to provide the required time interval. 

PHRASEOLOGY− HOLD FOR WAKE TURBULENCE. 

EXAMPLE #1 - A B738 is departing the runway at full length. A C172 calls for departure from the same runway at an intersection. A 3 minute timer shall be started once the B738 is airborne. The C172 cannot start its takeoff roll until the time has expired. The C172 can request to waive this time requirement.

EXAMPLE #2 - A B752 is departing the runway at full length. A C172 calls for departure from the same runway at an intersection. A 3 minute timer shall be started once the B738 is airborne. The C172 cannot start its takeoff roll until the time has expired. The C172 cannot request to waive this time requirement.

EXAMPLE #3 - You are working CSM tower. A B744 is departing full length 17R. A C172 calls for departure at full length runway 17L. A 3 minute timer shall be started once the B744 is airborne. The C172 cannot start its takeoff roll until the time has expired. The C172 cannot request to waive this time requirement.

3−10−3. SAME RUNWAY SEPARATION 

a. Separate an arriving aircraft from another aircraft using the same runway by ensuring that the arriving aircraft does not cross the landing threshold until one of the following conditions exists:

1. The other aircraft has landed and is clear of the runway. Between sunrise and sunset, if you can determine distances by reference to suitable landmarks and the other aircraft has landed, it need not be clear of the runway if the following minimum distance from the landing threshold exists: 

(a) When a Category I aircraft is landing behind a Category I or II− 3,000 feet.

(b) When a Category II aircraft is landing behind a Category I or II− 4,500 feet. 

2. The other aircraft has departed and crossed the runway end. If you can determine distances by reference to suitable landmarks and the other aircraft is airborne, it need not have crossed the runway end if the following minimum distance from the landing threshold exists: 

(a) Category I aircraft landing behind Category I or II− 3,000 feet. 

(b) Category II aircraft landing behind Category I or II− 4,500 feet. 

(c) When either is a category III aircraft− 6,000 feet.

WAKE TURBULENCE APPLICATION

b. Issue wake turbulence advisories, and the position, altitude if known, and the direction of flight of: 

1. The super or heavy to aircraft landing behind a departing/arriving super or heavy on the same or parallel runways separated by less than 2,500 feet. 

2. The B757/large aircraft to a small aircraft landing behind a departing/arriving B757/large aircraft on the same or parallel runways separated by less than 2,500 feet. 

3−10−4. INTERSECTING RUNWAY/INTERSECTING FLIGHT PATH SEPARATION

Issue traffic information to each aircraft operating on intersecting runways. 

a. Separate an arriving aircraft using one runway from another aircraft using an intersecting runway or a nonintersecting runway when the flight paths intersect by ensuring that the arriving aircraft does not cross the landing threshold or flight path of the other aircraft until one of the following conditions exists: 

1. The preceding aircraft has departed and passed the intersection/flight path or is airborne and turning to avert any conflict. (See FIG 3−10−6 and FIG 3−10−7.)

2. A preceding arriving aircraft is clear of the landing runway, completed landing roll and will hold short of the intersection/flight path, or has passed the intersection/flight path. (See FIG 3−10−8 and FIG 3−10−9.) 

b. “USA/USAF/USN NOT APPLICABLE.” LAHSO procedures shall only be used where published information exists (Depicted on airport diagrams or chart suppliments). The following conditions apply: 

1. A simultaneous takeoff and landing operation must only be conducted in VFR conditions. 

2. Instruct the landing aircraft to hold short of the intersecting runway being used by the aircraft taking off. In the case of simultaneous landings and no operational benefit is lost, restrict the aircraft of the lesser weight category (if known).

3. Issue traffic information to both aircraft involved and obtain an acknowledgment from each. Request a read back of hold short instructions when they are not received from the pilot of the restricted aircraft. 

4. Issue the measured distance from the landing threshold to the hold short point rounded “down” to the nearest 50−foot increment if requested by either aircraft. 

6. Land and Hold Short runways must be free of any contamination, with no reports that braking action is less than good 

7. There is no tailwind for the landing aircraft restricted to hold short of the intersection. The wind may be described as “calm” when appropriate.

8. The aircraft required landing distances are listed in the current LAHSO directive. 

PHRASEOLOGY− HOLD SHORT OF RUNWAY (runway number), (traffic, type aircraft or other information).