Why is a single-engine go-around so dangerous in a light twin?

A single-engine go-around combines slow airspeed, high landing-configuration drag, asymmetric thrust from the operating engine, and close proximity to the ground all at once. The aircraft may have zero or even negative climb capability in full landing configuration on one engine, and if airspeed drops near Vmc, directional control can be lost. The FAA Airplane Flying Handbook states that a single-engine go-around should be avoided whenever possible.

What should I do if I lose directional control below Vmc during a go-around?

The immediate, primary response is to reduce power on the operating engine and lower the nose to regain airspeed. Reducing power eliminates the asymmetric thrust that is causing the loss of control. This is not a last resort — it is the first action, and delaying it while trying to maintain full power below Vmc will result in a rapid, uncontrollable yaw and roll toward the dead engine.

What is the correct flap retraction procedure during a single-engine go-around?

Flaps should be retracted incrementally — in stages — rather than all at once. Retracting full flaps instantly removes a large amount of lift and can cause the aircraft to sink into the ground at the worst possible moment. Each stage of flap retraction should be followed by allowing the aircraft to accelerate before removing the next increment of flaps.

The Single-Engine Go-Around and Why It Is So Hazardous

Of all the emergencies a multi-engine pilot can face, few demand more immediate, precise action than an engine failure during the approach and landing phase — and few decisions are more consequential than the choice to execute a go-around on one engine. The single-engine go-around sits at the intersection of the most hostile aerodynamic conditions a light twin will ever encounter: the aircraft is slow, configured for landing, close to the ground, and suddenly being asked to climb while fighting severe asymmetric thrust. Understanding exactly why this maneuver is so hazardous — and how to execute it correctly when it must be done — is essential knowledge for every multi-engine pilot.

The FAA Airplane Flying Handbook (FAA-H-8083-3C, Chapter 13) addresses this topic with unusual directness: a single-engine go-around is to be avoided if at all possible. That is not timidity — it is a frank acknowledgment of the aerodynamic realities involved. Let's examine those realities in detail.

The Aerodynamic Stack-Up: Why Everything Goes Wrong at Once

To appreciate the danger, consider what the aircraft's state looks like at the moment an engine fails on short final or during a balked landing. Airspeed is near approach speed — often close to or even below Vyse (blue-line speed), the best single-engine rate-of-climb speed. Full flaps and landing gear are extended, generating enormous drag. The aircraft may be in ground effect or just above it. Power on the operating engine is being pushed to maximum, creating a massive asymmetric yawing and rolling moment precisely when the pilot has the least energy reserve to counteract it.

Each of these factors alone is manageable. Together, they form what experienced instructors call a lethal aerodynamic stack-up.

Drag: The Silent Killer

Landing configuration drag is substantial. Full flaps on most light twins can increase drag dramatically compared to a clean configuration. Retractable gear, when extended, adds further parasite drag. When one engine is out, the remaining engine must overcome all of this drag plus the additional drag of a windmilling propeller — a large, flat-pitch, spinning disk that can produce more drag than a feathered propeller by a significant margin. The net result is that the aircraft's single-engine climb capability, already marginal on many light twins, may be zero or even negative in full landing configuration. Some aircraft simply cannot climb on one engine with gear and full flaps extended; they will descend regardless of pilot technique.

Asymmetric Thrust and Vmc

The operating engine at full power creates a powerful yawing moment toward the failed engine, and a rolling moment in the same direction. On a conventional light twin with both propellers rotating clockwise as seen from the pilot's seat, the critical engine is the left engine. The reason is P-factor: each engine's descending (right) blade produces more thrust than the ascending blade. The right engine's descending blade is farther from the aircraft's centerline, giving it a longer moment arm. If the left engine fails, the right engine's thrust is not only unbalanced but offset far from the CG, producing the maximum possible yawing moment to the left. Losing the right engine instead would produce less asymmetric moment because the left engine's thrust line is closer to the center.

This is why Vmc — the minimum control speed with critical engine inoperative — is so critical during a go-around. Vmc is defined under 14 CFR Part 23 as the calibrated airspeed at which, with the critical engine suddenly made inoperative, the pilot can maintain directional control and hold a heading with no more than 5° of bank. Importantly, Vmc is purely a directional control standard — it says nothing about climb capability. An aircraft can be above Vmc and still be descending.

On a go-around, the pilot must add full power on the operating engine. This dramatically increases the asymmetric yaw. If airspeed is at or below Vmc at that moment, the rudder cannot overcome the yawing moment, and directional control is lost. On approach, with a sink rate, the aircraft may already be at or below blue-line speed, putting it dangerously close to — or already below — Vmc. Adding full power to one engine in this condition can be catastrophic.

Why the Go-Around Decision Must Be Made Early

The window for a successful single-engine go-around closes rapidly as the approach progresses. At pattern altitude with gear and flaps up, a competent pilot in a capable twin has a fighting chance of climbing away. At 200 feet AGL on short final with full flaps and landing gear extended, the math often simply does not work. The aircraft may lack the single-engine climb gradient to clear obstacles, the pilot may lack the altitude to accelerate to a safe airspeed, and the proximity to the ground eliminates all margin for error.

This is why the FAA guidance is unambiguous: land the airplane. If an engine failure occurs during the approach and a safe landing area is within reach, the pilot should continue to land rather than attempt a go-around. The go-around should only be considered if landing is truly not possible — for example, a runway blocked by a ground vehicle — and even then the pilot must immediately assess whether the aircraft can actually perform the maneuver given its current energy state and configuration.

Executing the Maneuver When It Cannot Be Avoided

If a single-engine go-around must be executed, the sequence of actions matters enormously. The FAA Airplane Flying Handbook's guidance for this scenario emphasizes:

Mixtures, props, throttles — bring the operating engine to maximum power smoothly but without delay. Simultaneously, verify the inoperative engine is identified and secured (feathered if not already done).
Retract flaps incrementally — do not retract all flaps at once. Remove flaps in stages, allowing airspeed to increase between steps. Retracting all flaps instantly dumps lift and dramatically increases the aircraft's descent rate at the worst possible moment.
Retract landing gear — once a positive rate of climb is established, or if a positive rate cannot be established and terrain is an immediate concern, retract the gear to reduce drag.
Accelerate to Vyse — blue-line speed is the target. Do not attempt to climb at speeds below Vyse; below that speed, single-engine climb performance degrades. Establish the zero-sideslip condition (approximately 2° of bank into the operating engine) to maximize performance.
Maintain directional control — aggressive use of rudder into the operating engine is required from the moment power is applied. Do not allow the aircraft to yaw or roll toward the dead engine.

One critical point the handbook emphasizes: if airspeed decays toward or below Vmc during a go-around and control becomes difficult, the immediate response is to reduce power on the operating engine and lower the nose to regain airspeed. This removes the asymmetric thrust that is driving the loss of control. It feels counterintuitive, but reducing power is the primary recovery action — not a last resort. Maintaining full power while below Vmc will lead to loss of control far more quickly than reducing power and accepting a descent.

Key Numbers and Rules

Vyse (blue line): best single-engine rate-of-climb speed — the target airspeed once a positive climb is established.
Vxse: best single-engine angle-of-climb speed — used when obstacles must be cleared; produces a steeper but slower climb.
Vsse: safe single-engine speed — the minimum speed at which single-engine training maneuvers should be initiated.
Vmc: determined at most unfavorable conditions — lightest weight, aft CG, maximum takeoff power, gear retracted, no more than 5° bank. Vmc is not established at max gross weight. Vmc increases as weight decreases.
Zero-sideslip bank: approximately 2° into the operating engine, combined with rudder to maintain heading — produces best OEI climb performance by minimizing fuselage drag.
Below Vmc response: reduce power on the operating engine and lower the nose immediately.

Common Test Traps

Thinking Vmc is a climb guarantee. Vmc is purely a directional control speed. An aircraft can be well above Vmc and still be unable to climb on one engine in landing configuration.
Believing the right engine is critical. On a conventional twin with clockwise-rotating propellers, the left engine is critical. Counter-rotating propellers eliminate the critical engine entirely.
Thinking Vmc is lowest at light weight. The opposite is true — Vmc increases as weight decreases, making light weight the most unfavorable condition for Vmc. Heavy weight gives the banked-lift vector more authority against the rudder, lowering the effective Vmc.
Retracting all flaps immediately on go-around. Flaps must be retracted incrementally to avoid suddenly losing lift and driving the aircraft into the ground.
Treating power reduction as a last resort below Vmc. Reducing power on the operating engine is the primary, immediate response when control is being lost below Vmc — not a desperate final action.