Engine Failure — Why Aircraft Simply Keep Flying

Few scenarios cause as much unease among passengers as the thought of an engine failure in flight. The notion that an engine fails and the aircraft falls from the sky is one of the most widespread myths in aviation. The reality is entirely different: an engine failure is not a catastrophic event but a well-manageable scenario that pilots are intensively trained for and for which every commercial aircraft is certified.

Why an Engine Failure Does Not Mean a Crash

Modern commercial aircraft are designed so that they can not only fly safely with one engine inoperative but can even climb. This capability is not an optional feature but a mandatory certification requirement. No commercial aircraft receives its type certificate without demonstrating safe flight performance on a single operating engine.

The requirements include, among others:

• Single-Engine Climb Performance: The aircraft must be able to safely climb with one engine inoperative following a rejected takeoff above the decision speed V1.
• Minimum Rate of Climb: Even at maximum takeoff weight, a positive climb gradient must be achieved on one engine.
• Obstacle Clearance: The required climb gradient guarantees clearance from obstacles in the departure path.
• Landing Capability: Landing with only one engine must be possible without restrictions.

ETOPS — How Twin-Engine Aircraft Cross Oceans

One of the most compelling pieces of evidence for the safety of single-engine flight is the ETOPS system (Extended-range Twin-engine Operational Performance Standards). Under both EASA and FAA regulations, this framework allows twin-engine aircraft to fly routes that take them far from alternate airports — because engine reliability is so exceptionally high.

ETOPS-370 means in concrete terms: an Airbus A350 is permitted to operate up to 370 minutes — over six hours — from the nearest suitable airport. This is only possible because the statistical probability of an engine failure is extremely low, and the aircraft can continue flying safely and in a controlled manner on a single engine.

Statistical Reliability of Modern Engines

Modern jet engines are among the most reliable machines ever built. The failure rate is approximately one event per 100,000 to 300,000 flight hours, depending on the engine type. For comparison: a long-haul pilot typically flies 800 to 900 hours per year. Statistically, a pilot could spend their entire career without ever experiencing an engine failure.

This reliability is the result of:

• Strictest Manufacturing Standards: Every component is inspected and certified multiple times, in compliance with EASA Part 21 and FAA Part 33 regulations.
• Regular Inspections: Engines are disassembled and overhauled at fixed intervals (shop visits).
• Real-Time Monitoring: Modern Engine Health Monitoring (EHM) systems monitor hundreds of parameters in real time and detect anomalies before they lead to failures.
• Redundant Systems: Oil pumps, fuel pumps, ignition systems — everything is duplicated or triplicated.

What Happens When an Engine Actually Fails?

If an engine fails, a standardized procedure follows that every airline pilot regularly practices in the simulator:

• Detection: Vibrations, asymmetric thrust, warning messages on the flight deck.
• Securing: The failed engine is shut down, fuel supply is cut off, and the fire suppression system is activated if necessary.
• Asymmetric Flight: Slight rudder input compensates for the yaw. Modern fly-by-wire systems partially handle this automatically.
• Decision: Depending on the flight phase, either continue to the destination or divert to the nearest suitable airport.
• Landing: A completely normal landing, merely at a slightly higher approach speed.

The Glide Ratio — Why Even Without Engines It Is Far From Over

Even in the extremely unlikely event of a total engine failure, an aircraft is not a stone falling from the sky. Every aircraft — whether glider, Cessna, or Airbus — has a glide ratio that indicates how far it can glide per unit of altitude lost.

An Airbus A320 can therefore glide over 112 miles (180 kilometers) from normal cruising altitude — roughly the distance from London to Birmingham and back. A Boeing 777 can cover even more than 124 miles (200 km). This gives the pilots plenty of time and numerous options to reach a suitable airport.

Real-World Cases — The Evidence from Practice

Aviation history knows numerous cases in which engine failures were successfully managed:

British Airways Flight 38 — London Heathrow, 2008

On January 17, 2008, both Rolls-Royce Trent 800 engines of a Boeing 777 simultaneously suffered a loss of thrust shortly before landing at Heathrow. The cause was ice crystal formation in the fuel lines. The pilots managed to touch the aircraft down on the grass just short of the runway. All 152 people on board survived. This incident led to worldwide modifications to fuel systems.

US Airways Flight 1549 — The Miracle on the Hudson, 2009

On January 15, 2009, an Airbus A320 lost both engines only 90 seconds after takeoff from LaGuardia when a flock of Canada geese was ingested. Captain Chesley Sullenberger and First Officer Jeffrey Skiles successfully ditched the aircraft on the Hudson River. All 155 occupants survived. This case impressively demonstrates that even the worst-case scenario — total engine failure at low altitude over a major city — is survivable.

Gimli Glider — Air Canada, 1983

A Boeing 767 ran out of fuel mid-flight due to a confusion between pounds and kilograms during refueling. The captain, an experienced glider pilot, glided the aircraft over 60 miles (100 km) to a decommissioned military airfield in Gimli, Manitoba. All occupants were uninjured.

Backup Systems — When Engines Provide More Than Just Thrust

Modern engines provide not only thrust but also hydraulic pressure, electrical power, and bleed air for the air conditioning and cabin pressurization systems. What happens when these sources are lost?

• APU (Auxiliary Power Unit): A small auxiliary engine in the tail of the aircraft. It can supply electrical power and bleed air independently of the main engines. The APU can be started at any altitude and serves as the first backup layer.
• RAT (Ram Air Turbine): A small wind turbine that deploys from the fuselage in an emergency. The airstream drives it and generates enough electrical power and hydraulic pressure to operate the most critical control surfaces and instruments. The RAT deploys automatically upon total power loss.
• Batteries: Lithium-ion or nickel-cadmium batteries provide emergency power for at least 30 minutes — enough for an emergency descent and landing.
• Windmilling: Even a failed engine continues to rotate in the airstream (so-called windmilling) and can still generate limited hydraulic pressure.

The Redundancy Philosophy of Aviation

All of aviation is built on the principle of redundancy: every safety-critical system exists at least in duplicate, often in triplicate. This applies not only to engines but to the entire aircraft systems architecture.

• Hydraulic Systems: Typically three independent circuits (e.g., on the A320: Green, Blue, Yellow).
• Electrical Systems: Multiple generators, transformers, and batteries.
• Flight Controls: Multiple redundant Flight Control Computers.
• Navigation: Multiple independent navigation systems (IRS, GPS, VOR, DME).
• Communications: Multiple VHF and HF radios, satellite telephone.

This philosophy means: a single failure — whether an engine, a generator, or a hydraulic pump — never leads to an uncontrollable situation.

Engine Failure in General Aviation

In single-engine general aviation (GA) aircraft, an engine failure is naturally more serious since there is no second engine available. Nevertheless, the situation is manageable if the pilot responds correctly:

• Immediately establish the best glide speed: Every aircraft has an optimal speed for maximum glide distance (e.g., Cessna 172: approx. 65 knots).
• Search for a suitable landing field: Fields, roads, open areas.
• Attempt a restart: Often the engine can be restarted (carburetor icing, fuel starvation).
• Execute a forced landing: PPL training includes intensive practice for forced landings.

Statistically, most forced landings in GA end without serious injuries, provided the pilot maintains control and selects a suitable landing field.

Conclusion — Engine Failure Is Manageable

An engine failure is a serious event but not a cause for panic. The combination of redundant systems, intensive pilot training, strict certification requirements (enforced by both EASA and the FAA), and the inherent gliding capability of every aircraft makes it a manageable scenario. The history of aviation proves time and again: even in the worst case — total engine failure — a safe landing is possible. This fact is no coincidence but the result of decades of systematic safety work in aviation.