Aerodynamic End Cap Structure for Stable Launch Tube Ejection

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Solution Overview

Problem

Existing end caps for common launch tubes on military aircraft exhibit erratic flight trajectories upon ejection, posing a risk of striking the host aircraft, particularly for wing-mounted launch tubes on pusher-prop aircraft.

Innovation Solution

The development of stabilized end caps with aerodynamic configurations, including peripheral extensions and fins, to provide controlled and predictable trajectories during ejection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a simple aluminum cap is used to cover the common launch tube end, then the device complexity is reduced and ease of manufacture is improved, but the flight stability deteriorates and the risk of aircraft strike increases

Engineering Contradiction:
Improveend cap structureVSAvoidflight trajectory stability
Core Design Contradiction:
Device complexityVSStability of the object's composition

Solution Approach 1:

The end cap incorporates curved aerodynamic surfaces including a rounded leading edge and a curved trailing edge, replacing the flat simple aluminum cap design. These curved surfaces are specifically shaped to generate aerodynamic forces that stabilize the cap's flight trajectory after ejection, preventing erratic motion while maintaining manufacturing feasibility through standard aerodynamic profiling techniques.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The end cap is divided into distinct functional segments: a central body portion, a peripheral extension with aerodynamic configuration, and a trailing edge section. Each segment serves a specific aerodynamic function - the central body provides structural integrity, the peripheral extension generates lift and control forces, and the trailing edge manages flow separation. This segmentation allows optimization of each portion's aerodynamic contribution while keeping the overall design manufacturable.

Inventive Principle:
Principle #1Segmentation

2Stability of the object's composition

If an aerodynamic configuration with peripheral extensions is added to the end cap, then the flight stability is improved and trajectory predictability is enhanced, but the device complexity increases and manufacturing difficulty rises

Engineering Contradiction:
Improveflight trajectory stabilityVSAvoidend cap manufacturing
Core Design Contradiction:
Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

Multiple aerodynamic functions are merged into a single integrated peripheral extension structure rather than using separate components. The peripheral extension simultaneously provides lift generation, directional control, and structural attachment to the central body. This consolidation reduces the number of parts, simplifies assembly procedures, and allows the entire aerodynamic assembly to be manufactured as one piece using standard aerospace fabrication techniques.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The aerodynamic configuration parameters such as extension width, curvature radius, and angle of attack are optimized within specific ranges to achieve stable flight characteristics. By carefully selecting these geometric parameters, the design achieves adequate aerodynamic performance without requiring overly complex shapes or precision tolerances that would significantly increase manufacturing difficulty. The parameters are tuned to provide robust stability across varying flight conditions.

Inventive Principle:
Principle #35Parameter changes

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 stabilized end caps reduce the likelihood of aircraft strikes by ensuring a more stable and predictable trajectory, enhancing safety for host aircraft.

Implementation Method 1

the peripheral extension is provided with an aerodynamic configuration

Methodology Applied
Scientific EffectAerodynamic configuration: Aerofoil

Data Source

PatentUS12540792B2Stabilized end cap for common launch tube
Publication Date: 2026.02.03 THE GOVERNMENT OF THE UNITED STATES AS REPRESENTED BY THE SECRETARY OF THE AIR FORCE
  • US12540792B2 patent drawing
  • US12540792B2 patent drawing
  • US12540792B2 patent drawing

AI summary

A stabilized end cap for covering one end of a common launch tube on a military aircraft is disclosed. The stabilized end cap includes a central body having a portion with a disk-shape configuration. In some cases, the stabilized end cap has a peripheral extension that extends radially outward from the periphery of the central body, and the peripheral extension is provided with an aerodynamic configuration. In other cases, the stabilized end cap has at least one aerodynamic extension extending longitudinally outward from the outside surface of the central body.