PAT-9901-PHAN-SENSOR: Dual Sensor Redundancy Tied to Single Processing Core — Structural Failure Pattern | PatternDB

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PAT-9901-PHAN-SENSORARCHETYPE: Phantom Redundancy (Common-Mode Failure)

Dual Sensor Redundancy Tied to Single Processing Core

Sub-Type: Apparent Hardware Backup with Shared Logic Chokepoint

VEC:AUTH:0.72•COUP:0.91•LAT:0.68•OVR:0.85

Authority Gradient

0.72

Feedback Coupling

0.91

Telemetry Latency

0.68

Override Suppression

0.85

Structural Pattern Audit Brief

Critical Multi-Node (Level 4)PAT-9901-PHAN-SENSOR

Aircraft carries two physical angle-of-attack sensors, but software is architected to poll only one sensor per flight cycle, rendering hardware redundancy useless.

Failure Invariant Breach

Sensors [A, B] -> Flight_Computer (Hardcoded Single Channel Poll) -> Actuator

Absent Safety Recovery Mechanism

Real-time voting comparator and anomaly disengage interrupt

Fundamental Invariant Rules

INV-01:Physical sensor redundancy provides zero fault tolerance if downstream logic executes single-point polling without comparator voting.

Engineered Resilience & Mitigation Strategies

MIT-01:Hardware and software voting mechanisms across all redundant sensor banks

MIT-02:Automated fallback to raw manual pilot direct-law mode upon sensor disagreement

Canonical Incident Manifestations (3)

NTSB-FAA-2018-1029Commercial Aviation

Lion Air Flight 610: MCAS Angle-of-Attack Runaway Oscillation & Pilot Muscle Fatigue

Automated stabilization routine commanded persistent state modifications driven by single corrupted sensor. Human Decision_Node counter-actions were repeatedly overridden by recurring loop iterations until physical control buffer depleted.

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NIST-CVE-2020-8597Cloud Infrastructure & Networking

Cloudflare / Multi-Cloud Redundancy: Single Anycast DNS Routing Cascade Outage

Dual-node infrastructure designed for redundant failover shared an unmodeled single-point DNS Telemetry_Channel. Upstream channel failure disconnected both independent computation nodes simultaneously.

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CISA-FBI-2021-0507Critical Energy Infrastructure & Cyber

Colonial Pipeline: Single-Factor Legacy VPN Credential Reuse & 5,500-Mile Pipeline Shutdown

Single-factor credential vulnerability breached IT telemetry enclave. Fear of uncontained malware propagation across IT/OT boundary forced Decision_Nodes to execute total physical infrastructure shutdown.

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