AINsight: What To Do before and after a Rejected Takeoff

Rejected takeoffs (RTOs) are a non-normal maneuver that all professional pilots routinely practice and are formally assessed during both initial and recurrent training sessions. In the simulator, there is a lot of focus on the decision-making leading up to the RTO and the actual maneuver of getting the aircraft stopped on the runway—often overlooked is what to do after the RTO on the runway and back on the ramp.

Outside of the simulator, RTOs are rare in line operations. An RTO is an event where a takeoff is aborted and the aircraft is brought to a stop during the takeoff roll. RTOs include three phases: planning and briefing, actions during the maneuver, and post-RTO tasks.

During the 1990s, NASA ASRS published a study, “Rejected Takeoffs: Causes, Problems, and Consequences,” by Capt. Roy Chamberlin. It cited a 1989 Boeing 737 runway overrun accident (USAir Flight 5050) that involved flight crew deficiencies before, during, and after the takeoff rejection. Accordingly, “Contributing to these human performance errors were external conditions that were not perceived by the flight crew as being relevant to the operating decisions.”

The study found that “RTOs introduce multiple risks—those associated with the takeoff abort process itself, and those associated with the events which may follow. They are symptomatic of a breakdown in human performance that can lead to improper aircraft conditions and configurations.” It continued, “A successfully managed RTO involves a skillful blending of pilot perception and appropriate action to conclude the abort procedure safely and avoid dangerous follow-on events.”

Before the RTO—Decision-making

During multi-crew operations, every takeoff briefing includes a detailed discussion on the airspeeds that will affect decisions to reject (or stop) the takeoff up to V1—the takeoff decision speed.

The discussion on whether to stop or go is based on different airspeed regions and the actions required for various malfunctions or conditions. These briefings help flight crews formulate a mental model between each other of what to expect during various points on the takeoff roll. In general, there is a low-speed region (below 80 knots) and a high-speed region (above 80 knots up to V1).

A low-speed RTO is accomplished for any significant or abnormal situation. In this region, below 80 knots, an RTO is warranted for the following: engine fires/failures, master caution/warning lights, system failures, unusual noises and vibrations, tire failure, slow acceleration, windshear warnings, or if the aircraft is unsafe or unable to fly.

Challenges in this region include directional-control issues below the minimum controllable airspeed on the ground (Vmcg), where the rudder may not be effective. Pilots often, during these low-speed scenarios, must control the aircraft using nose wheel steering either through rudder pedals or the tiller and differential braking.

A high-speed RTO is accomplished for major malfunctions such as engine failures and fire or if the aircraft is unsafe or unable to fly. Above 80 knots, it is recognized that the closer the speed gets to V1 the risk increases and the ability to stop the aircraft on the runway decreases. After V1, the RTO should only be considered if there is a strong reason to believe that the aircraft will not fly.

Tire failures during the takeoff roll have been the cause of inappropriate decisions to reject the takeoff at higher speeds. A tire failure will affect the calculated stopping distance due to the loss of braking force on the associated wheel.

In 2008, a Bombardier Learjet 60 crashed at South Carolina’s Columbia Metro Airport (KCAE) when the pilot attempted to reject the takeoff due to a tire failure after V1. Following the tire failure, the aircraft departed the end of the runway, crashed through the airport boundary fence, crossed a highway, and burst into flames as it came to rest on an embankment. Four people onboard the aircraft were killed and two others were critically injured.

The final NTSB accident report attributed the accident to tire bursts during the takeoff and the captain’s decision to abort at a high speed. According to the report, several tires were severely under-inflated and failed during takeoff. Pieces of the tires damaged the aircraft’s hydraulic system, causing the brake system to fail.

Airbus and other manufacturers recommend that in the case of a tire failure, the takeoff should be continued if the airspeed is greater than V1 minus 20 knots. Continuing the takeoff allows the aircraft to become airborne, reduces the fuel load, and land with the full runway length available.

RTO Maneuver—The Easy Part

RTO procedures vary by aircraft by manufacturer. The concept for each is the same: maximize the stopping power of the aircraft by reducing thrust, apply maximum braking, and reduce the lift on the wing by extending ground spoilers (to increase braking effectiveness), and deploying the thrust reversers, if installed.

These procedures are committed to memory—this is the easy part. Coordination between the captain and first officer is essential. Most company SOPs have the captain acting to bring the aircraft to a stop, while the first officer assists by monitoring systems (braking, spoilers, etc.), makes the appropriate callouts, and notifies ATC as time permits.  

After the RTO—More Decision-making

One section of the NASA RTO study focused on flight crew decisions following an RTO. The study found that “decisions made by the flight crews in the wake of an RTO were based largely on their perceptions of aircraft integrity. These perceptions were shaped by warning system alerts, tactile sensing, engine instrument indications, aircraft-generated noises, and observations radioed by tower controllers or other external observers.”

The NASA study found many areas that are problematic to flight crews following an RTO such as requesting emergency equipment, using brake energy charts to determine tire condition, an ill-advised second takeoff attempt, and a decision to evacuate the aircraft.

Following an RTO and once the aircraft is stopped, the flight crew must accomplish all required EICAS/ECAM or QRH abnormal procedures. In the event of a significant event such as a fire (engine or brake), an emergency evacuation may be required.

Emergency evacuation checklist must be readily available; flight deck flows committed to memory and practiced in the aircraft or simulator—remembering details such as a completely dark cockpit when battery switches are selected “OFF.”

If an emergency evacuation is required, ensure that ATC has been properly notified. The NASA study found that ATC was “uniformly of great assistance to RTO aircraft.”

Other considerations include the possibility of wheel fuse plugs melting, advising ground crew of hot brakes, and clearing the runway, if able.

After the RTO—Pro Tips

After a low-speed RTO, aircraft are often legally allowed to attempt another takeoff. Examples include ATC-directed rejects or minor aircraft system anomalies that can be resolved through an approved system reset table or procedure. Regardless, the FAA classifies these as an RTO, even if they occur at a very low speed.

A high-speed RTO typically will result in a significant delay or return to the ramp due to brake cooling (brake energy charts) and other issues.

In the U.S., all RTOs are logged by the local controller at a tower-controlled airport. Subsequent actions by the FAA include a review/investigation by an FAA Safety Inspector.

Following an RTO, accomplish these steps:

• Ensure that the flight crew makes the appropriate maintenance logbook entry, even if the aircraft is returned to a normal status using a system reset table or procedure. This is required by the applicable FAA regulations (91.1025, 121.563, or 135.65—see below). The absence of a maintenance logbook entry may result in FAA enforcement actions, such as a letter of warning.

• Complete and submit any company hazard or event reports.

• If safety is compromised, complete and submit an ASAP or NASA ASRS report.

Simulator training is a great opportunity to learn and refine your airmanship skills. During your next trip to the simulator take the time to review all three phases of the RTO. Review takeoff rejection criteria, practice both low- and high-speed RTOs, then complete the scenario through to evacuation or completion of other non-normal procedures, including all necessary administrative tasks like logbook entries and required reports.  

FARs related to required maintenance logbook entries:

91.1025 Program operating manual contents.

Each program operating manual accessed in paper format must display the date of last revision on each page. Each program operating manual accessed in electronic format must display the date of last revision in a manner in which a person can immediately ascertain it. Unless otherwise authorized by the Administrator, the manual must include the following:

(a) Procedures for ensuring compliance with aircraft weight and balance limitations;

(b) Copies of the program manager's management specifications or appropriate extracted information, including area of operations authorized, category and class of aircraft authorized, crew complements, and types of operations authorized;

(c) Procedures for complying with accident notification requirements;

(d) Procedures for ensuring that the pilot in command knows that required airworthiness inspections have been made and that the aircraft has been approved for return to service in compliance with applicable maintenance requirements;

(e) Procedures for reporting and recording mechanical irregularities that come to the attention of the pilot in command before, during, and after completion of a flight;

(f) Procedures to be followed by the pilot in command for determining that mechanical irregularities or defects reported for previous flights have been corrected or that correction of certain mechanical irregularities or defects have been deferred;

121.563 Reporting mechanical irregularities.

The pilot in command shall ensure that all mechanical irregularities occurring during flight time are entered in the maintenance log of the airplane at the end of that flight time. Before each flight the pilot in command shall ascertain the status of each irregularity entered in the log at the end of the preceding flight.

135.65 Reporting mechanical irregularities.

(a) Each certificate holder shall provide an aircraft maintenance log to be carried on board each aircraft for recording or deferring mechanical irregularities and their correction.

(b) The pilot in command shall enter or have entered in the aircraft maintenance log each mechanical irregularity that comes to the pilot's attention during flight time. Before each flight, the pilot in command shall, if the pilot does not already know, determine the status of each irregularity entered in the maintenance log at the end of the preceding flight.

(c) Each person who takes corrective action or defers action concerning a reported or observed failure or malfunction of an airframe, powerplant, propeller, rotor, or appliance, shall record the action taken in the aircraft maintenance log under the applicable maintenance requirements of this chapter.

(d) Each certificate holder shall establish a procedure for keeping copies of the aircraft maintenance log required by this section in the aircraft for access by appropriate personnel and shall include that procedure in the manual required by FAR 135.21.