Thermoplastic Aircraft Control Surface With Induction-Consolidated Truss Core
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing control surfaces for aircraft made from thermoset materials face challenges in achieving higher structural performance, particularly at higher in-service temperatures, and require longer production times due to curing processes, while newer applications demand thinner wings with greater fracture toughness and residual strength.
Innovation Solution
A control surface composed of a truss core and a skin, both made from thermoplastic materials, is fabricated using induction consolidation, with the truss core having a top and bottom chord and webs connecting them, and the sections are joined using induction welding or smart susceptors for faster production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If thermoset materials with honeycomb core and facesheets are used, then continuous attachment is achieved, but propagation of disbonds occurs and production time increases
Solution Approach 1:
The patent changes the material parameter from thermoset to thermoplastic, which fundamentally alters the consolidation process. Thermoplastics can be rapidly heated to melting point and consolidated quickly, then cooled to set the structure. This parameter change enables both high residual strength through complete consolidation and rapid production cycles without lengthy curing times.
Solution Approach 2:
The patent utilizes phase transitions of thermoplastic materials - heating above melting point to enable consolidation, then cooling to solidify the structure. This phase transition approach allows for rapid consolidation and production, eliminating the long curing times associated with thermoset materials while achieving complete consolidation and high residual strength.
2Reliability
If thermoset materials are used for control surfaces, then structural integrity is achieved, but production rate decreases
Solution Approach 1:
Changing from thermoset to thermoplastic materials fundamentally changes the processing parameters. Thermoplastics can be consolidated rapidly through heating and cooling cycles, enabling high production rates while maintaining structural integrity through complete consolidation and proper material selection.
Solution Approach 2:
The patent replaces the chemical curing mechanism of thermosets with a thermal-mechanical consolidation process using thermoplastics. This substitution allows for rapid heating and cooling cycles that achieve complete consolidation and structural integrity without the time-consuming chemical curing process, thereby increasing production rate.
3Strength
If thicker wings are used, then structural strength is improved, but weight increases
Solution Approach 1:
The patent employs composite materials consisting of thermoplastic matrix with reinforcement fibers (such as carbon or glass fibers). This composite structure provides high fracture toughness and structural strength in thin sections, eliminating the need for thicker wings while maintaining required performance and reducing weight.
Solution Approach 2:
The patent applies reinforcement fibers strategically within the thermoplastic matrix to provide localized strength where needed. This local quality approach enables thin-walled structures to achieve required fracture toughness through targeted reinforcement rather than uniform thickness increases, thereby reducing overall weight.
4Ease of manufacture
If thermoset control surfaces are used, then manufacturing is established, but adaptation to higher temperatures is limited
Solution Approach 1:
The patent changes the material parameter from thermoset to high-performance thermoplastic, which fundamentally improves temperature resistance. Thermoplastics such as PEEK, PEKK, and PPSU can operate at higher temperatures while maintaining mechanical properties, enabling adaptation to higher in-service temperature environments while preserving fabrication ease through established thermoplastic processing methods.
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 control surface achieves higher residual strength, improved fracture toughness, and damage tolerance, allowing operation at higher temperatures with reduced production time and improved fabrication efficiency.
Implementation Method 1
consolidating the cover and the spar and/or assembling the forward and aft sections together by induction consolidation
Implementation Method 2
the sections are joined using induction welding or smart susceptors
Data Source
Figure 1~2
Figure 3
Figure 4~5A
AI summary
A thin, lightweight control surface is fabricated by induction consolidation of thermoplastic components. The control surface includes a forward section co-consolidated with a rear section. The front section includes a cover and the rear section includes a truss core covered by an outer skin.