Second Segment Climb
Understanding the second segment climb is vital for ensuring obstacle clearance and maintaining safety in the event of an engine failure during take-off, especially in multi-engine operations. It directly impacts take-off mass planning, aircraft configuration, and emergency procedures.
The second segment climb is a critical phase of the multi-engine take-off profile, beginning after gear retraction and continuing to the acceleration altitude. During this segment, the aircraft climbs at V2 speed with take-off thrust on the operating engine(s), flaps in the take-off position, and gear up. The main objective is to achieve a minimum regulatory climb gradient to ensure obstacle clearance in the event of an engine failure.
Quick Check
During the second segment climb of a multi-engine aircraft, which configuration is correct?
Go beyond the textbook.
Explanation
Second Segment Climb Explained
The second segment climb starts immediately after the landing gear is fully retracted, following the first segment of the take-off. At this point, the aircraft is configured with flaps in the take-off position, gear up, and is flown at V2—the take-off safety speed. For regulatory compliance, this segment assumes the failure of the critical engine (for multi-engine aircraft) and requires the remaining engine(s) to deliver take-off thrust.
The aircraft must achieve a minimum climb gradient, which is specified by regulations and varies depending on the number of engines. This is to ensure that, even with one engine inoperative, the aircraft can safely clear obstacles beyond the runway. The climb continues at V2 until reaching the acceleration altitude, typically at least 400 ft above the runway, but this can be extended if obstacles are further away.
If distant obstacles require a higher climb, the second segment can be extended upward, provided engine time limits at take-off thrust are not exceeded. Once at acceleration altitude, the aircraft transitions into the third segment, where it accelerates and retracts flaps.
Key Factors Affecting Second Segment Climb
- Weight: Higher aircraft weight reduces climb gradient and rate, making it harder to meet regulatory requirements.
- Configuration: Flaps remain in the take-off position and gear is up—this balances lift and drag for optimal climb performance.
- Speed: V2 is maintained for best engine-out climb performance.
- Thrust: Remaining engine(s) provide maximum take-off thrust.
- Climb Gradient vs. Angle: Climb gradient is the ratio of height gained to distance traveled, expressed as a percentage; climb angle is the inclination above the horizontal.
Regulatory Requirements
The second segment climb requirement is non-negotiable for certification and operational safety. The aircraft must demonstrate compliance at all approved weights, altitudes, and temperatures, ensuring safe performance even in the most challenging conditions.
Key Points
Exam Traps & Typical Mistakes
Example Exam Questions
What is the primary regulatory requirement for the second segment climb gradient in a twin-engine aircraft?
Why might the second segment climb be extended beyond the normal acceleration altitude?
Still not fully confident?
Deepen your knowledge with an AI tutor built specifically for EASA ATPL students.
Built from thousands of ATPL knowledge references, real exam references and official learning objectives.
Open Avi AI TutorRelated Concepts
Still have questions?
Ask questions in plain English and get exam-focused explanations from an AI tutor built specifically for EASA ATPL students.
Open Avi AI