The October 3 a plane crash involving flight FR88265 of Ryanair made the news at Brindisi airport. The flight, directed to Bologna and operated by a Boeing 737-800suffered a flame in one of its engines while still on the runway while taxiing. The pilots, reacting promptly, aborted the take-off and brought the plane back to safety. Fortunately, no passengers were injured. But what caused the blaze and how did the crew react? Let’s discover the possible technical causes and the procedures that allowed the emergency to be managed safely.
Possible causes of an engine flameout
Flare-ups in jet engines can occur for a variety of technical reasons, and pilots must be ready to react quickly, especially during critical phases such as takeoff. Let’s see some of the main causes that can cause a blaze, such as the one observed in the Brindisi accident.
Compressor stalling
The jet engine works thanks to a continuous and uniform flow of compressed air that enters the compressor and is sent to the combustion chamber. However, if this flow is interrupted or becomes erratic, the compressor may “stall“. In this case, combustion stops temporarily and unburned fuel can build up and eventually explode when combustion resumes, causing a visible flame on the outside of the engine.
Problems with fuel injection
The fuel injection system of jet engines is extremely precise, but a malfunction can lead to excessive injection of fuel in the combustion chamber. If this excess fuel is not burned immediately, it can build up and subsequently ignite all at once, creating a blaze. This situation can occur suddenly, especially during the acceleration phases for take-off, as happened in Brindisi.
Mechanical damage
Another possible cause of a flameout can be internal damage to the engine, such as breakage of a compressor or turbine blade. These components play a vital role in maintaining airflow and smooth combustion. If one of them becomes damaged, the engine may not work properly, causing irregular combustion and, consequently, a flameout.
Adverse weather conditions
Although not always considered the first cause, atmospheric conditions such as very strong wind, heavy rain or turbulence can affect the normal air flow in the engine. For example, heavy rain can rapidly cool critical engine parts, altering the combustion process and causing flare-ups or temporary combustion interruptions.
The crew’s emergency response
One of the first and most critical decisions pilots must make during takeoff concerns the speed of decision V1. This speed, specific to each aircraft and variable based on factors such as weight and weather conditions, represents the point of no return in the takeoff process. Before reaching V1, pilots can still abort takeoff and ensure they have enough runway needed to stop the aircraft safely on the runway. However, once past V1, takeoff must continue, even in an emergency, as stopping could be dangerous.
In the case of the Ryanair flight to Brindisi, the aircraft was still under V1 when the blaze occurred. It is assumed that the aircraft was stopped in the first 200 meters of the runway, this allowed the crew to carry out a take-off aborted (RTO, Rejected Takeoff) at low speed fortunately and stop the plane safely. The readiness and training of the crew were key to effectively managing the situation.
After the takeoff was rejected, the pilots activated the fire handlean essential tool in emergency fire situations on Boeing 737s. The fire handle is designed to isolate the affected engine and minimize the risk of fire spreading. Once pulled, the fire handle immediately stops:
- Air conditioning: The flow of conditioned air to the engine is blocked, avoiding further fueling the fire;
- Fuel: The fuel supply to the engine is cut off, preventing further combustion;
- Electricity: The electrical current to the motor is interrupted, reducing the risk of short circuits;
- Hydraulic fluid: Blocks the flow of hydraulic fluid to the engine, limiting further mechanical damage.
After isolating the engine, pilots can manually activate the fire extinguishers present on board to try to put out the fire. These fire extinguishers release chemicals, usually high pressure halogen, which suffocate the flames within the engine, reducing the risk of catastrophic damage.
How the fire detection system works
Modern airplanes, such as the Boeing 737, are equipped with sophisticated fire detection systems, designed to quickly spot any thermal anomalies or overheating in the engines. One of the most common systems is the a system loop cables. These consist of temperature sensitive conductors, installed around the motor. When the temperature inside the engine compartment increases beyond a certain limit, the resistance inside the cables changes. This change in resistance is detected by the aircraft’s monitoring system and sends a signal to the cockpit. At this point, the crew receives several alarm signals:
Fire handle red: The fire handle for the engine in question lights up red, indicating the presence of a fire or critical overheating.
Audible alarm: An alarm bell sounds to alert pilots to the need for immediate action.
This system ensures that the pilot is alerted instantly, allowing for a timely reaction. Once these signals are received, the crew must follow emergency procedures, such as activating the fire handle and fire extinguishers, to neutralize the fire and ensure the safety of the aircraft.
The Ryanair accident in Brindisi highlighted this the importance of crew preparation and advanced technologies on board modern aircraft. Although a blaze may seem scary, it is manageable thanks to a combination of pilot training, advanced detection systems and standardized procedures. The V1 decision speed, the use of the fire handle and fire detection systems such as loop cables are all essential tools that allow you to deal with emergency situations quickly and effectively. Even in a critical event like this, passenger safety always remains the top priority.