EFL RX DSMX 6-Ch AS3X/SAFE BL ESC P-EFLA6421BL

Overview

The E-Flite RX DSMX 6-Channel AS3X/SAFE BL ESC (Model P-EFLA6421BL) is a comprehensive receiver and electronic speed controller combination designed specifically for ultra-micro RC aircraft. This integrated unit combines DSMX receiver technology with a brushless electronic speed controller, making it an ideal choice for pilots looking to upgrade or build their own micro RC planes with advanced stability and safety features. Whether you're a seasoned RC enthusiast or exploring the world of brushless RC aircraft for the first time, this unit delivers professional-grade performance in a compact package that won't compromise your aircraft's weight or balance.

This receiver and ESC combination is particularly popular among UK RC enthusiasts building ultra-micro aircraft, as it provides the advanced features you'd find in larger-scale RC setups but scaled down for the precision flying required in micro applications. The integration of AS3X and SAFE technologies means your aircraft will benefit from electronic stabilisation and flight envelope protection, making it more forgiving during learning phases whilst still offering the control and responsiveness that experienced pilots demand.

The P-EFLA6421BL represents excellent value for builders of ultra-micro RC aircraft who want reliable, feature-rich electronics without the complexity of managing separate components. Its compatibility with Spektrum transmitters and the broader E-Flite ecosystem ensures you're investing in equipment that will serve you well across multiple aircraft builds and upgrades.

Key Features

• Integrated DSMX Receiver and Brushless ESC — This unit combines both the radio receiver and electronic speed controller in one compact housing, which significantly reduces weight and complexity in your ultra-micro aircraft build, whilst maintaining full control authority across all six channels.
• AS3X Stability System — AS3X (Attitude Stabilisation via Gyro Sensing) automatically compensates for wind turbulence and pilot input errors, keeping your micro aircraft stable and predictable even in challenging conditions, which is especially valuable when flying in gusty UK weather.
• SAFE Technology Integration — SAFE (Sensor Assisted Flight Envelope) protection prevents you from flying the aircraft beyond its safe operating parameters, automatically limiting control inputs that could cause stalls or inverted flight in hover, making this an excellent choice for developing your RC piloting skills.
• DSMX Radio Protocol — The latest-generation Spektrum DSMX protocol ensures secure, interference-free communication with your transmitter, offering superior range and reliability compared to older 2.4GHz systems.
• 6-Channel Control Capability — This six-channel configuration provides control of throttle, elevator, aileron, rudder, plus two additional channels that can be assigned to flaps, landing gear, or other auxiliary functions depending on your aircraft design.
• Brushless Motor Compatibility — The integrated brushless ESC is optimised for the power characteristics and performance envelope of ultra-micro brushless motors, delivering smooth, responsive power delivery without the maintenance requirements of brushed alternatives.
• Compact Ultra-Micro Form Factor — Engineered to fit within the tight space constraints of ultra-micro aircraft without sacrificing functionality, this unit maintains the minimal weight profile essential for small-scale RC flying.

Technical Performance

The E-Flite RX DSMX 6-Channel AS3X/SAFE BL ESC represents a significant advancement in ultra-micro RC aircraft electronics. Built with brushless ESC technology, this unit delivers efficient power management and extended flight times compared to brushed alternatives, whilst the integrated receiver eliminates the need for a separate component, saving both weight and complexity. The DSMX receiver operates on the 2.4GHz frequency band, providing secure, spread-spectrum communication that resists interference in crowded RC flying environments. The AS3X gyro-stabilisation system continuously monitors aircraft attitude and automatically applies corrective inputs to the control surfaces, working seamlessly in the background to smooth out turbulence and enhance control response. The SAFE flight envelope protection works in conjunction with AS3X to prevent dangerous flight attitudes, automatically limiting elevator and throttle inputs if the aircraft approaches critical angles of attack. This combination of technologies makes the P-EFLA6421BL particularly well-suited to ultra-micro aircraft platforms that demand both performance and protection, whether you're building a high-wing trainer, a sport plane, or an aerobatic micro that pushes the boundaries of what small-scale RC can do. The brushless ESC is engineered to provide reliable power delivery across the broad throttle range required by micro aircraft, from gentle, stable powered flight to dynamic aerobatic manoeuvres.

What's in the Box

• E-Flite RX DSMX 6-Channel AS3X/SAFE Brushless ESC receiver unit

What You Need to Complete

• Compatible Spektrum DSMX transmitter (such as DXS, NX6, NX8 or other approved Spektrum radio)
• Ultra-micro brushless motor appropriate for your aircraft design
• LiPo battery compatible with your aircraft (typically 2S 7.4V for micro applications)
• Battery connector as specified by your ESC manual
• Servo motors for control surfaces (aileron, elevator, rudder as required)
• Control linkages, pushrods and bellcranks for your specific airframe
• RC aircraft airframe kit or custom-built airframe suitable for ultra-micro dimensions

Frequently Asked Questions

• What is AS3X and how does it improve my RC flying experience? — AS3X is Spektrum's Attitude Stabilisation via Gyro Sensing technology that continuously monitors your aircraft's pitch, roll and yaw angles using built-in gyroscope sensors. It automatically applies subtle corrective inputs to the control surfaces in real-time, compensating for wind gusts, turbulence and unintended pilot input errors. This means your ultra-micro aircraft will feel more stable and predictable in flight, reducing the workload on the pilot and making it far more forgiving for those learning to fly RC aircraft. Even experienced pilots appreciate AS3X because it allows smoother, more controlled flights in variable wind conditions that would otherwise demand constant manual correction.
• What does SAFE technology do and why is it important for ultra-micro aircraft? — SAFE (Sensor Assisted Flight Envelope) protection uses the same onboard sensors as AS3X to establish flight envelope limits that prevent dangerous flight attitudes. It automatically limits how far the aircraft can pitch up or down, preventing stalls and loss of control, and can prevent inverted flight in hover mode if that's not something your aircraft is designed for. This is particularly important in ultra-micro aircraft where recoveries from unusual attitudes can be difficult, and it makes SAFE an excellent feature for developing your skills safely without fear of inadvertently crashing due to over-controlling.
• Is this ESC suitable for beginners building their first RC aircraft? — Yes, the P-EFLA6421BL is an excellent choice for RC aircraft builders of all experience levels. The integrated receiver and ESC simplifies your build by eliminating the need to mount and wire separate components, and the AS3X and SAFE technologies work together to make the aircraft more forgiving and stable, which is ideal when you're learning to fly. However, you will need a compatible Spektrum DSMX transmitter and you'll need to understand basic RC aircraft assembly, so it's not a plug-and-play ready-to-fly option, but rather a component for builders with some technical confidence.
• What radio transmitter do I need to use with this receiver? — The P-EFLA6421BL requires a Spektrum DSMX transmitter to communicate with the integrated receiver. Compatible options include the Spektrum DXS, Spektrum NX6, Spektrum NX8 and other approved Spektrum radio systems that support DSMX protocol. You cannot use this receiver with non-Spektrum transmitters or older Spektrum DSM2 radios.
• What battery voltage and capacity do ultra-micro aircraft typically use with this ESC? — Ultra-micro aircraft, including platforms like the E-Flite Turbo Timber UMX, typically use 2S LiPo batteries rated at 7.4 volts. Battery capacities for ultra-micros range from 200mAh to 300mAh, offering flight times of approximately 5 to 10 minutes depending on flying style and aircraft design. Always consult your specific airframe's manual for recommended battery specifications to ensure safe operation and optimal performance.
• Can I use this ESC in different aircraft, or is it only for one specific model? — The P-EFLA6421BL is designed as a general-purpose receiver and ESC combination for ultra-micro aircraft applications, so it can be used across different ultra-micro aircraft builds provided they're compatible with 2S 7.4V battery systems and appropriate brushless motors. However, each aircraft installation will require careful integration work including mounting the receiver securely, routing control linkages and calibrating the system, so it's not simply a case of moving it between different airframes without modification.
• What is the difference between this integrated receiver/ESC and separate components? — Using an integrated unit like the P-EFLA6421BL saves significant weight and reduces the complexity of your build compared to installing separate receiver and ESC modules, both critical advantages in the weight-sensitive ultra-micro category. The tradeoff is that if one component fails, the entire unit requires replacement rather than swapping just one component, though the integrated design is generally more reliable in the tightly-sealed environment of a micro aircraft fuselage. The integrated approach also simplifies wiring and reduces potential connection points where failures could occur.

Why Buy from RC Model Shop?

RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the EFL RX DSMX 6-Ch AS3X/SAFE BL ESC P-EFLA6421BL today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.

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