Aircraft Cockpit Door Deceleration Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cockpit doors in aircraft accumulate high kinetic energy during decompression, leading to potential structural damage and crew injury due to delayed venting and inadequate energy dissipation, necessitating a rapid and controlled deceleration mechanism to manage the door's rotation and energy absorption.
Innovation Solution
A deceleration device comprising a spool reel, belt, elevating spindle, collet, and spring assembly that automatically connects to the cockpit door to absorb kinetic energy through a reacting force, utilizing compression springs and an energy-absorbing tube to dissipate energy progressively and prevent damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the door is designed with reinforced construction to meet post-9/11 security rules, then door strength and security are improved, but kinetic energy increases due to higher moment of inertia
Solution Approach 1:
The patent converts the harmful high kinetic energy of the reinforced door into a beneficial controlled deceleration process. The door's kinetic energy is harnessed to drive the spool reel, which winds the belt and activates the spring assembly, transforming the potentially damaging energy into a controlled mechanism that ensures both security and safety.
Solution Approach 2:
The patent introduces an intermediary deceleration mechanism comprising the spool reel, belt, and spring assembly. This intermediary system mediates between the reinforced door and the cockpit interior, allowing the door to maintain its strength while the intermediary components manage the kinetic energy during opening, preventing direct impact with seats or structures.
2Productivity
If the door unlocks rapidly and rotates through to minimum venting area quickly, then venting effectiveness is improved, but kinetic energy and risk of damage increase
Solution Approach 1:
The patent implements preliminary action by pre-positioning the spring assembly and belt system before decompression occurs. The spring assembly is pre-loaded and ready to engage, and the belt is pre-attached to the door. When decompression occurs, the system immediately begins controlling the door's motion, allowing rapid venting while preventing damage through pre-established protective mechanisms.
Solution Approach 2:
The patent applies dynamics by making the deceleration mechanism active and adaptive during door rotation. The spring assembly progressively engages as the door opens, providing increasing resistive force that dynamically adjusts to the door's kinetic energy. This dynamic system allows rapid initial opening for venting while progressively slowing the door to prevent impact damage.
3Stress or pressure
If the door is allowed to rotate open unhindered to minimum free venting area, then pressure difference load is reduced, but kinetic energy causes impact damage
Solution Approach 1:
The patent introduces an intermediary deceleration mechanism comprising the spool reel, belt, and spring assembly. This intermediary system mediates between the reinforced door and the cockpit interior, allowing the door to maintain its strength while the intermediary components manage the kinetic energy during opening, preventing direct impact with seats or structures.
Solution Approach 2:
The patent converts the harmful high kinetic energy of the reinforced door into a beneficial controlled deceleration process. The door's kinetic energy is harnessed to drive the spool reel, which winds the belt and activates the spring assembly, transforming the potentially damaging energy into a controlled mechanism that ensures both security and safety.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The deceleration device effectively reduces the kinetic energy of the cockpit door by up to 40% while maintaining structural integrity and minimizing pressure load on the cockpit wall, ensuring safe and controlled door rotation without adverse effects on the airframe or crew.
Implementation Method 1
the deceleration device includes at least one spring assembly which is installed between the collet and a fixed bearing portion of the deceleration device. Hence, the at least one collet will be screwed towards the fixed bearing portion by retraction of the belt from the spool reel whereby the spring assembly will be compressed, so that a reaction load is generated by the spring assembly counteracting the retraction of the belt.
Data Source
AI summary
A deceleration device adapted for gradual dissipation of kinetic energy comprises a spool reel carrying a belt being wound up on the spool reel; an elevating spindle being driven by the spool reel when the belt is being retracted from the spool reel; at least one collet screwed to the elevating spindle; and at least one spring assembly being installed between the collet and a fixed bearing portion of the deceleration device. The at least one collet is screwed towards the fixed bearing portion by retraction of the belt from the spool reel thereby compressing the spring assembly, whereby a reaction load is generated by the spring assembly counteracting the retraction of the belt.