According to the Aeronautical Information Manual, “Line up and wait is an air traffic control (ATC) procedure designed to position an aircraft onto the runway for an imminent departure. The ATC instruction ‘LINE UP AND WAIT’ is used to instruct a pilot to taxi onto the departure runway and line up and wait.” In earlier aviation days, not that many years ago, this was known as “position and hold” but the phrase was updated to provide additional clarity.
An ATC Procedure
As is indicated by the definition above, line up and wait is an ATC procedure. It is conducted at tower controlled airports where the tower controller knows what he or she has instructed the previous aircraft to do. The reason for a line up and wait instruction is often due to a prior aircraft still being on the current runway or a crossing runway and the controller wanting to expedite the takeoff of the line up and wait aircraft. The reason for expediting this takeoff may be that there is another aircraft on final or in the pattern that will soon be ready to land. The controller is in a position to see all three aircraft and make modifications if the timing is off or there is a delay due to a pilot error in one of the aircraft.
You should be aware, that a line up and wait instruction from ATC is not an authorization to takeoff. You should expect an authorization to takeoff shortly after the controller is satisfied that the condition that delayed you is now safe. If you do not receive a takeoff clearance within a reasonable amount of time, you should contact the controller and remind him or her that you are there. Accidents have occurred after a controller forgot an aircraft waiting on the runway and cleared another airplane to land on that same runway.
A note in the Aeronautical Information Manual indicates, “FAA analysis of accidents and incidents involving aircraft holding in position indicate that two minutes or more elapsed between the time the instruction was issued to line up and wait and the resulting event (for example, land−over or go−around). Pilots should consider the length of time that they have been holding in position whenever they HAVE NOT been advised of any expected delay to determine when it is appropriate to query the controller.”
Even when following line up and wait instructions at tower controlled airport, it is important for you as the pilot in command to remain vigilant and situationally aware. Listen to the instructions and clearances that the tower is giving to other aircraft in the area. If you hear a clearance to land where you are currently waiting, be alert and ready to call the tower if necessary. You might also consider lining up at a slight angle that affords a better view of landing aircraft approaching behind you.
You should be especially vigilant at night, during reduced visibility, and when the airport is using line up and wait operations on more than one runway. Listen carefully for your call sign and the runway that you are using. Be alert for similar sounding call signs and avoid following the instructions for a different aircraft than yours. When in doubt, contact ATC for clarification. If you are unable to raise ATC, have an escape plan for getting you and your aircraft to a safe location if you are concerned about another aircraft landing in your location.
If you are the landing aircraft and you hear ATC give line up and wait instructions to an aircraft on the runway to which you have been cleared to land, be extra vigilant to ensure that the aircraft has departed before you land. Even if you haven’t heard a line up and wait clearance, be sure that runway is clear before landing. Do not hesitate to ask ATC about any traffic that you see on the runway where you are landing.
Line Up and Wait Is Not for Non-Towered Airports
Line up and wait procedures were never intended for use at non-towered airports despite being common practice with some pilots. As indicated, it is an ATC procedure. Without the additional eyes of the controller and his or her knowledge of the instructions issued to other aircraft, it is simply not a safe procedure to perform.
As the pilot in command of an aircraft that is ready to takeoff, you have no real idea of the intentions of the aircraft that is temporarily blocking your takeoff runway. Will she make the intersection? Will he roll the full length of the runway? How fast will she taxi to the runway exit? Is he oblivious to his surroundings and unsure where to turn? Will her takeoff follow a standard pattern departure? Will he abort the takeoff? You may think that you know but you really do not know when the runway will be clear.
Once you are positioned for takeoff, your ability to see the runway’s approach is seriously limited. How close is that final traffic getting? Is there another aircraft approach that is not using a radio? Does the approaching pilot see or hear you?
Is your life and the life of your passengers really not worth waiting until the runway is clear?