3001-109 - Textron Aviation OEM Overheat Fire Detector

3001-109 – Textron Aviation OEM Overheat Fire Detector

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The Textron Aviation 3001-109 is a flight-critical, OEM thermal spot-detector assembly engineered to provide rapid, fail-safe overheat and fire warning detection within high-risk zones of light jet and turboprop aircraft. Installed across strategic airframe fire zones—including engine nacelles, bleed-air duct routings, and auxiliary power unit (APU) compartments—this component acts as the primary sensory trigger for the cockpit fire protection loop. It is calibrated to monitor ambient thermal limits continuously, instantly completing an electrical grounding circuit to trigger master warning alerts and activate engine fire-extinguisher bottle squibs the moment an absolute temperature threshold is breached.

Manufactured to original type-design criteria under Textron Aviation oversight, the 3001-109 relies on a highly reliable, hermetically sealed thermal switch mechanism enclosed in a low-profile, corrosion-resistant housing. The structural envelope is engineered to endure intense thermodynamic cycling and high-frequency powerplant vibrations without experiencing calibration drift or structural fatigue. As an original factory-certified line replaceable unit (LRU), this spot detector integrates natively with the aircraft's existing master warning panel, eliminating signal processing lag and ensuring that the flight crew receives instantaneous warning tracking when an thermal breach occurs.

The 3001-109 represents the industry benchmark for structural fire detection reliability. Its self-resetting configuration allows the sensor to break the warning circuit once ambient temperatures drop back into a safe operational envelope, preventing false continuous alarms after a fire has been successfully extinguished. For corporate flight departments, regional fleet operators, and certified A&P/IA mechanics executing scheduled airframe inspections, choosing this genuine OEM sensor ensures full compliance with FAA and EASA airworthiness regulations, safeguarding the aircraft’s primary safety-of-flight infrastructure.

Key Features

• Hermetically Sealed Spot Thermal Switch: Features a gas-tight, rugged steel capsule to protect the internal contact elements from moisture, jet fuel vapors, and environmental salt spray.

• Automatic Self-Resetting Logic: Instantly breaks the warning loop when local temperatures drop below the calibration threshold, providing clear cockpit confirmation of a successful extinguishing event.

• High-Strength Structural Mount Base: Designed with integrated, dual-slot mounting flanges to provide an unyielding structural attachment capable of enduring high-G airframe buffet profiles.

• Low-Mass Precision Thermal Response: Engineered with a thin-wall, high-conductivity housing to maximize thermal transmittal speeds and minimize alarm latency.

• Genuine Textron Aviation Production: Factory-calibrated to match exact airframe temperature matrices, eliminating the false-alarm risks linked to unverified aftermarket alternatives.

Technical Specifications

• Part Number: 3001-109 (Cross-Reference: Fenwal / Kidde Aerospace Series equivalents)

• Component Type: Thermal Spot Fire / Overheat Detector Switch

• OEM Cataloguer: Textron Aviation (Hawker Beechcraft / Cessna)

• Calibration Threshold: Pre-set factory thermal limit (Specific temperature parameters must be validated using the active aircraft maintenance manual based on zonal classification)

• Circuit Configuration: Normally Open (Closes on Temperature Rise to provide structural ground path)

• Housing Material: High-Temperature Stainless Steel / Corrosion-Resistant CRES Alloy

• Electrical Interface: Standard threaded post-terminal configuration with ceramic insulating shoulder

• Input Voltage Accommodation: Optimized for 28 VDC Aircraft Essential Bus loops

• Environmental/Vibration Rating: Certified for engine nacelle placement under harsh RTCA DO-160 categories

• ECCN: 9A991.d

• Certification Status: Dual Airworthiness Release Eligible (FAA Form 8130-3 / EASA Form 1 Traceability)

Aircraft Compatibility

• Beechcraft King Air Fleet: King Air 90, 200, 300, and 350 Series platforms (Engine nacelle and wheel well overheat loops).

• Cessna Citation Family: Twin-engine business jet platforms utilizing localized spot detector warning arrays across bleed-air zones.

• Note: Final airframe configuration control, zonal effectivity, and tail-number part validation must be verified strictly by referencing the active aircraft Illustrated Parts Catalog (IPC) or relevant Supplemental Type Certificate (STC) documentation.

Applications

• Powerplant Fire Zone Monitoring: Positioned around engine exhaust profiles and accessory gearboxes to detect structural shell breaches or fuel fires.

• Bleed-Air Leak Detection: Placed along primary environmental control system (ECS) high-pressure line runs to detect catastrophic duct failures.

Why Choose 3001-109?

Sourcing a trace-certified OEM Textron 3001-109 fire detector protects your fleet from catastrophic thermal damage and costly uncommanded flight diversions. Low-tier commercial or unverified sensors frequently manifest internal switch-contact contamination or mechanical bimetallic fatigue over time. This deterioration causes the sensor to jam open (failing to report an active engine fire) or short closed unexpectedly. A false fire alarm in flight forces immediate emergency checklist execution, engine shutdown, and halon bottle discharge, inflicting extensive operational costs and risking passenger safety. The 3001-109 undergoes rigid production test filtering to maintain calibration trueness across thousands of flight hours, providing clean diagnostic protection when it matters most.

The electronic operation of the Textron Aviation 3001-109 turns on the physics of differential thermal expansion and hermetic contact isolation within a variable-pressure environment. The internal switch capsule houses a bimetallic curved strut assembly or thermal expansion element engineered with an precise coefficient of thermal expansion. As ambient heat flux rises during a localized fire or bleed-air leak, the outer stainless steel shell expands linearly at a faster rate than the low-expansion internal strut matrix. This physical elongation creates an axial mechanical strain that snaps the internal, low-resistance electrical contacts together.

Because the switch operates in a normally open, single-wire configuration, the closing of the contact elements immediately routes the 28 VDC essential bus loop to the airframe ground plane, initializing the cockpit audio-visual warning tracking. The hermetic seal prevents dielectric ionization breakdowns and arc-tracking at extreme altitude drops, ensuring that the sensor’s threshold parameters remain perfectly repeatable across rapid temperature transients and high vibration zones.

Note: The Textron Aviation 3001-109 is an ultra-critical flight safety component. Dropping the unit, denting the outer stainless steel casing, or over-torquing the electrical terminal stud can physically distort the internal bimetallic alignment, destroying its temperature calibration and rendering the detector inoperative. Component installation, structural alignment, and loop continuity testing must be executed exclusively by a certified A&P/IA mechanic or authorized Part 145 MRO station in strict compliance with the aircraft's Maintenance Manual (Chapter 26). Always verify that the underlying airframe mounting flange is entirely free of paint and corrosion to ensure a perfect low-resistance ground path during system integration.

Documentation

No public-facing OEM or regulatory documentation was located for this part. Final dimensional tolerances, schematic wiring routes, and regulatory target clearance criteria must be verified directly via a licensed Textron Aviation Technical Publications or Interactive Electronic Technical Manual (IETM) subscription portal.