Engine Failure After Takeoff in a Light Twin
You are pilot-in-command of a light twin-engine aeroplane, MTOW 2,100 kg, departing Runway 09 (length 1,100 m, elevation 400 ft, slope 1% uphill, dry asphalt) on a hot day. OAT is 30°C, QNH 1013, wind calm. Before takeoff you calculate that the accelerate-stop distance is 950 m and the takeoff distance to 50 ft is 1,050 m. Just after rotation, at about 90 ft AGL, the right engine fails. The aeroplane yaws right; you apply rudder and identify the failed engine. Airspeed is 85 KIAS, Vmc is 78 KIAS, Vyse is 95 KIAS, and single-engine best angle is 88 KIAS. The aerodrome has open flat terrain ahead for 2 km, then rising ground. The undercarriage is still down.
1. What are your immediate priorities and control actions, and what performance reasoning drives them?
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Immediate priorities: maintain control, then configure for best single-engine climb, then decide.
Control actions:
- Apply rudder to counter yaw and hold a small bank toward the live engine (typically 5° or less) to reduce sideslip and improve single-engine performance.
- Pitch to maintain a safe speed above Vmc; at 85 KIAS you are above Vmc (78) but below Vyse (95) and below best angle (88). With gear down and low altitude, the priority is to stop the descent and clear obstacles.
- Identify, verify, and feather the failed engine per the checklist; do not feather before identification is confirmed.
- Retract the undercarriage only when a positive rate of climb is assured and terrain permits; gear drag at this altitude is significant.
Performance reasoning: at 30°C and 400 ft elevation, density altitude is roughly 2,300–2,500 ft, which degrades both engine power and wing/thrust performance. The takeoff distance to 50 ft of 1,050 m on a 1,100 m runway leaves almost no margin; an engine failure at 90 ft is above the 50 ft screen height, so the aeroplane is committed and a forced landing ahead is the realistic option if climb performance is inadequate. With gear down, single-engine climb gradient may be near zero or negative. The rising ground 2 km ahead means a turn back is not viable at this height; the correct decision is to lower the nose, maintain Vmc-plus margin, clean up, and land ahead in the open flat area if altitude cannot be gained. The exam tests the link between density altitude, configuration drag, and the go/no-go decision, not the memory of a number.
2. How does the uphill slope and the runway length affect your pre-takeoff planning, and what would you change?
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A 1% uphill slope increases the takeoff distance and reduces acceleration, and it makes an aborted takeoff harder because deceleration is assisted only slightly by gravity while the climb-out is penalised. With a 1,100 m runway and a calculated takeoff distance to 50 ft of 1,050 m, the margin is only 50 m (about 4.5%), which is inadequate for a hot day with no wind.
Planning changes:
- Recompute with slope and temperature corrections from the aircraft flight manual; if the corrected distance exceeds the available runway, reduce takeoff mass (fuel or payload) until the margin is acceptable.
- Use a reduced-power or improved-climb technique only if the AFM permits it and the obstacle clearance is re-verified.
- Select a decision point (e.g., a speed or distance marker) before which a rejected takeoff is possible, and brief it.
- Consider a different runway or aerodrome with a headwind component or downhill gradient.
- Brief the engine-failure procedure for the specific departure, including the turn or straight-ahead option and the terrain ahead.
The key reasoning is that published takeoff distances assume specific conditions; slope, temperature, pressure altitude, and wind must each be applied, and a small margin is not a margin at all. The correct answer is to reduce mass or change runway, not to accept the calculation.