Aircraft Takeoff Weight Calculation for Engine-Out Climb Compliance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Aircrafts face challenges in meeting climb gradients during engine failure due to reduced climb performance, necessitating weight reduction options like reducing passengers or fuel, which are undesirable, and alternate departure procedures lack validation and integration in flight management systems, increasing pilot workload.

Innovation Solution

An aircraft system with processors to predict liftoff location and energy state, generate potential trajectories, and iteratively adjust weight to ensure compliance with flight envelopes, providing maximum takeoff weight and minimizing pilot workload.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the aircraft weight is reduced to meet the SID-required climb gradient in engine failure scenarios, then the climb performance is improved, but the payload capacity (passengers, cargo, or fuel) is reduced

Engineering Contradiction:
Improveclimb performanceVSAvoidaircraft weight
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The system performs preliminary calculations during flight planning to determine the maximum allowable takeoff weight that ensures compliance with climb gradients in engine failure scenarios. This allows the aircraft to be loaded to the maximum safe weight before departure, eliminating the need for weight reduction during operations.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The aircraft's onboard system automatically calculates and determines the maximum takeoff weight based on aircraft-specific performance data, environmental conditions, and SID requirements. This self-service capability eliminates the need for manual weight reduction decisions by pilots and ensures accurate, real-time weight determination.

Inventive Principle:
Principle #25Self-service

2Adaptability or versatility

If alternate departure procedures (ODP/SODP) are created by third parties with different methods, then the flexibility to handle obstacle clearance is improved, but the validation and standardization of these procedures is worsened

Engineering Contradiction:
Improvedeparture procedure flexibilityVSAvoidprocedure validation
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The system provides a universal calculation method that works for all aircraft types and departure scenarios. By using aircraft-specific performance data and standardized flight envelope constraints, the system creates a multi-functional solution that can handle various obstacle clearance requirements while maintaining consistency and reliability across different operations.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system incorporates iterative testing and validation where calculated trajectories are assessed against flight envelope constraints. This feedback mechanism ensures that alternate departure procedures are properly validated and verified before use, improving reliability while maintaining the flexibility to handle different obstacle clearance scenarios.

Inventive Principle:
Principle #23Feedback

3Loss of information

If pilots reference paper or electronic versions of alternate departure procedures during high workload periods, then the accessibility to departure information is improved, but the pilot workload and complexity of operation is worsened

Engineering Contradiction:
Improvedeparture information accessibilityVSAvoidpilot workload
Core Design Contradiction:
Loss of informationVSEase of operation

Solution Approach 1:

The aircraft system automatically determines and provides the maximum takeoff weight information to the pilots without requiring them to manually reference external documents. This self-service approach eliminates the need for pilots to consult paper or electronic versions of alternate departure procedures during high workload periods, reducing workload while maintaining full access to necessary departure information.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system extracts and presents only the critical maximum takeoff weight information that pilots need for engine failure scenarios, removing the need to reference complete alternate departure procedure documents. This extraction of essential information reduces pilot workload while maintaining accessibility to the most important departure data.

Inventive Principle:
Principle #2Taking out (Extraction)

4Adaptability or versatility

If business aviation pilots use alternate departure procedures they have not previously practiced, then the adaptability to handle engine failure scenarios is improved, but the operational safety and ease of execution is worsened

Engineering Contradiction:
Improveengine failure scenario handlingVSAvoidprocedure execution
Core Design Contradiction:
Adaptability or versatilityVSEase of operation

Solution Approach 1:

The system performs preliminary calculations during flight planning to determine the maximum takeoff weight and provides this information to pilots before departure. This preliminary action ensures that pilots have the critical weight information they need before entering high-workload departure scenarios, improving ease of execution even when using unfamiliar alternate departure procedures.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The aircraft system automatically calculates and provides the maximum takeoff weight information, enabling business aviation pilots to handle engine failure scenarios without requiring extensive prior practice of specific alternate departure procedures. The self-service nature of the calculation provides pilots with the necessary information to execute procedures safely even when unfamiliar with the specific alternate departure route.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP4163899B1Maximum takeoff weight determination for aircraft
Publication Date: 2025.11.05 GULFSTREAM AEROSPACE CORP
  • EP4163899B1 patent drawingFigure 1
  • EP4163899B1 patent drawingFigure 2

AI summary

An aircraft has a first principles takeoff processor (PCE), a predictive flight envelope protection processor (PFEP), and a maximum takeoff weight processor. The PCE is programmed to predict a liftoff location and an energy state of the aircraft at a liftoff on a runway. The PFEP is programmed to assess each of a plurality of potential trajectories for compliance with or violation of a predetermined flight envelope. The maximum weight processor is programmed to: indicate that the aircraft may takeoff at the aircraft weight when any one of the plurality of potential trajectories is in compliance with the predetermined flight envelope; iteratively reduce an input of the aircraft weight to the PCE until the PCE indicates that any one of the plurality of potential trajectories is in compliance with the predetermined flight envelope; and indicate that the input of the aircraft weight as reduced is a maximum allowable takeoff weight.