Product Details
The E-flite UMX WACO blends classic style with state-of-the-art features including a 2S and 3S compatible power system and optional-use SAFE Select to give you one of the most rewarding Golden Age biplane flying experiences at any size!
Key Features
- An officially licensed scale replica of the modern-day yet classic YMF-5 biplane design
- The most affordable, convenient, capable, and easiest-to-fly WACO model yet
- More powerful 2S and 3S-compatible outrunner motor and ESC
- Easier to fly with optional-use SAFE Select flight envelope protection
- Factory-finished with a scale trim scheme available in two colour options
In The Box
- (1) E-flite UMX WACO 550mm
- (4) Spektrum Linear Servos (installed)
- (1) Spektrum Brushless Outrunner Motor (installed)
- (1) Spektrum Control Unit with
- (1) Receiver and (1) Brushless ESC (installed)
- (1) UMX WACO 550mm Product Manual
Needed to Complete
- (1) Full-range 5+ channel Spektrum DSMX compatible transmitter
- (1) 2S 7.4V or 3S 11.1V 280-300mAh LiPo with JST-RCY Connector (or JST-PH connector plus a suitable JST-RCY to JST-PH adapter sold separately)
- (1) Compatible LiPo Charger
Introduction
The Weaver Aircraft Company of Ohio (WACO) was founded by aviators whose love of flight and daring tenacity led them to produce over 60 different aircraft models in just 28 years. This made WACO one of the leading manufacturers of aircraft during the Golden Age of Aviation. In 1985 the founders of the Classic Aircraft Foundation set out to reincarnate the iconic YMF model. And now, the E-flite® UMX™ WACO has been updated and upgraded to be an even easier and more fun to fly tribute to the revered biplane! It's equipped with optional-use SAFE® Select, is both 2S and 3S compatible, plus provides real-time battery voltage telemetry to compatible transmitters. And because of its ultra-micro size, the UMX WACO can be flown indoors in gymnasiums and other suitable spaces, or outdoors in many yards, parks, and sports fields! It's an affordable, convenient, and easy to fly replica of the modern-day classic that's also available in two trim scheme colour options.
Features
- An officially licensed scale replica of the modern-day yet classic YMF-5 biplane design
- The most affordable, convenient, capable, and easiest-to-fly WACO model yet
- More powerful 2S and 3S-compatible outrunner motor and ESC
- Compatible with the Spektrum™ DXS transmitter included with many RTF models
- Real-time battery voltage telemetry with compatible Spektrum transmitters
- Spektrum receiver with industry-leading 2.4GHz DSMX® technology
- The unmatched stability and locked-in feel of exclusive AS3X® technology
- Easier to fly with optional-use SAFE® Select flight envelope protection
- Completely factory-assembled and ready to fly right out of the box
- Factory-finished with a scale trim scheme available in two colour options
- Scale details including simulated flying wires and a pilot figure with a scarf
Overview
This updated and upgraded version of the E-flite UMX WACO is now equipped with optional-use SAFE Select that makes it more stable than ever before, plus exclusive Spektrum™ AS3X® that keeps things smooth so it feels like you're flying a much larger model, even in windy conditions. The factory-installed brushless power system features an upgraded 2S- and 3S-compatible outrunner motor. Install 2S 280mAh batteries for performance similar to the original model, or use 3S 300mAh batteries for more speed and unlimited vertical performance. The control unit includes an ESC and Spektrum™ receiver that provides real-time flight battery voltage telemetry to compatible Spektrum AirWare™ equipped transmitters while you fly. It's constructed of advanced EPS material for a lightweight yet durable airframe, and it's now available in two trim scheme colour combinations including fully-painted yellow and lighter-weight unpainted white base versions. Best of all this Bind-N-Fly® Basic model arrives 100% factory-assembled and is ready to bind to your 5+ channel DSMX®/DSM2® equipped transmitter so you can be flying within minutes of opening the box! The lightly loaded biplane design and ultra-micro size are perfect for flying indoors in gymnasiums and similar large spaces, or outdoors pretty much anywhere - from yards to parks, sports fields, and beyond.
Bind-N-Fly Completion Level Advantage
Already own a Spektrum™ transmitter? Bind-N-Fly (BNF) aircraft make getting into the air quickly and with the best control experience possible easier than ever. They come out of the box with the power system, servos and a Spektrum 2.4GHz receiver installed so all you need to do is bind the receiver to a compatible transmitter, finish any final assembly and fly!
This Bind-N-Fly Basic model is equipped with a Spektrum 2.4GHz DSMX® receiver featuring AS3X® (Artificial Stabilization-3-aXis) technology that works behind the scenes to smooth out the effects of wind and turbulence so you enjoy a sense of stability and precision that makes it feel like you're flying a much larger, expertly tuned aircraft.
If this is your first model of its type, or you want an extra margin of safety while familiarizing yourself with the airplane, you can enable the optional-use SAFE® Select flight envelope protection technology built into the receiver. No programming is required.
With SAFE Select enabled, you get:
Pitch and Bank Angle Limits
- These envelope limits keep the airplane from rolling or pitching upside down. They also prevent excessive climb or dive angles.
Automatic Self-Leveling
- The airplane instantly returns to and holds level flight when the sticks are released and in the centre position. It's also helpful for keeping the wings level during takeoffs/launches and landings.
Easy Switch Assignment-No Complex Programming Required
- The simple procedure for assigning a transmitter switch to turn SAFE Select features on and off doesn't require any complex programming and takes just a few seconds. For UMX models like this one, SAFE Select is automatically assigned to channel 5 (Gear) so you can turn it on and off with any switch assigned to that channel (switch A by default on most Spektrum computer transmitters).
- Model: E-flite UMX WACO BNF Basic with AS3X and SAFE Select, Yellow
- Model Number: A-EFLU53550Y (EFLU5355X)
- Scale: Ultra-Micro (UMX)
- Aircraft Type: Biplane (officially licensed YMF-5 tribute)
- Wingspan: 550mm (21.65 inches)
- Length: 418mm (16.45 inches)
- Weight: 119g (4.2 oz) with recommended battery
- Airframe Material: Advanced EPS (expanded polystyrene)
- Construction Type: Fully factory-assembled, no assembly required
- Colour Option: Yellow (factory-finished; also available in unpainted white base)
- Power System Type: Electric brushless
- Motor Type: Spektrum brushless outrunner
- Motor Size: 1208–1900Kv, 10-pole
- Propeller: 5.75 x 2.50
- Battery Compatibility: 2S 7.4V 280–300mAh LiPo OR 3S 11.1V 300mAh LiPo
- Battery Connector: JST-RCY (or JST-PH with suitable adapter)
- ESC Type: Brushless, integrated into control unit
- Servos: Four Spektrum linear servos (pre-installed)
- Servo Mounting: Pre-installed
- Receiver: Spektrum 2.4GHz DSMX receiver (integrated into control unit)
- Receiver Technology: DSMX and DSM2 compatible
- Transmitter Required: Full-range 5+ channel Spektrum DSMX/DSM2 compatible transmitter (sold separately)
- Transmitter Compatibility: Compatible with Spektrum DXS, DX6e, DX8e, DX6 G2/3, DX8 G2, DX9, NX6–NX20, iX12–iX20 and other DSMX/DSM2 systems
- Flight Telemetry: Real-time flight battery voltage telemetry to compatible Spektrum AirWare equipped transmitters
- Flight Stability Technology: Spektrum AS3X (Artificial Stabilization–3-aXis)
- Flight Safety Technology: Optional-use SAFE Select flight envelope protection
- SAFE Select Features: Pitch and bank angle limits, automatic self-levelling, simple switch assignment (channel 5/Gear on most transmitters)
- Flying Weight Classification: Under 250g
- Completion Level: Bind-N-Fly (BNF) Basic
- Skill Level: Level 2 (some experience required)
- Suitable Flying Environments: Indoor (gymnasiums, hangars, large spaces) and outdoor (yards, parks, sports fields)
- Included Components: E-flite UMX WACO airframe 550mm, four Spektrum linear servos (installed), Spektrum brushless outrunner motor (installed), Spektrum control unit with receiver and brushless ESC (installed), product manual
- Required to Complete: Full-range 5+ channel Spektrum DSMX/DSM2 compatible transmitter, 2S 7.4V or 3S 11.1V 280–300mAh LiPo battery with JST-RCY connector, compatible LiPo charger
- Optional Parts Available: Battery hatches (yellow/white), wing sets, tail sets, landing gear sets, fuselage components, adapters
Overview
The E-flite UMX WACO is an officially licensed, ultra-micro tribute to the classic YMF-5 biplane, blending timeless Golden Age aviation styling with cutting-edge modern flight technology. This fully factory-assembled brushless RC aircraft represents one of the most rewarding and accessible biplane flying experiences available in the UK ready-to-fly RC market today. Whether you're an experienced RC pilot looking for a scale model that captures authentic aviation heritage, or an intermediate flyer seeking a responsive and feature-rich aircraft, the UMX WACO delivers exceptional value and performance in a package that's small enough to fly indoors in gymnasiums yet capable enough for outdoor flying in suitable spaces such as parks, sports fields, and gardens.
This Bind-N-Fly Basic aircraft arrives completely ready to fly straight out of the box, with all major components pre-installed and factory-tested. You simply need to bind it to your existing Spektrum transmitter, charge a compatible battery, and you can be airborne within minutes. The sophisticated brushless power system is compatible with both 2S and 3S LiPo batteries, giving you flexibility in how you want to fly—choose 2S for performance similar to the original model, or upgrade to 3S for increased speed and unlimited vertical capability. With exclusive AS3X stability technology and optional-use SAFE Select flight envelope protection, the UMX WACO provides a locked-in, precision flying experience that makes this scale biplane feel like a much larger, expertly tuned aircraft.
The airframe is constructed from lightweight yet durable advanced EPS material, finished in authentic factory paint schemes with scale details including simulated flying wires and a detailed pilot figure with a scarf. At just 119 grams with the recommended battery installed, this ultra-micro aircraft weighs well under 250 grams, making it accessible and practical for indoor and outdoor flying. The lightly loaded biplane design, combined with Spektrum's proven 2.4GHz DSMX receiver technology, ensures reliable control and the confidence you need to enjoy every flight.
Key Features
- Officially Licensed YMF-5 Scale Replica — This aircraft is a genuine, licensed tribute to the modern-day YMF-5 biplane, ensuring authentic proportions and styling that honour the classic design whilst incorporating contemporary aviation technology and engineering improvements.
- AS3X Stability Technology — Spektrum's exclusive Artificial Stabilization–3-aXis system works continuously in the background to smooth out the effects of wind and turbulence, delivering a locked-in feel that makes the aircraft handle like a much larger, professionally tuned model even in challenging flying conditions.
- Optional-Use SAFE Select Flight Envelope Protection — This intuitive flight assistance system can be toggled on and off in flight with a simple switch assignment, providing pitch and bank angle limits that prevent excessive attitudes, plus automatic self-levelling that returns the aircraft to level flight when the control sticks are centred—perfect for building confidence and expanding your skills safely.
- Dual Power System Compatibility (2S and 3S LiPo) — The upgraded brushless outrunner motor and ESC are engineered to work perfectly with either 2S 7.4V 280mAh or 3S 11.1V 300mAh LiPo batteries, giving you the freedom to choose your preferred performance characteristics and flight style.
- Real-Time Battery Voltage Telemetry — The integrated control unit transmits live flight battery voltage data to compatible Spektrum AirWare transmitters including the DX6e, DX8e, DX9, NX6 through NX20, and iX12 through iX20, allowing you to monitor power levels during flight and plan your landing accordingly.
- 100% Factory Assembled and Ready to Bind — Unlike many RC aircraft that require assembly, the UMX WACO arrives completely pre-assembled with all servos, motor, ESC, and receiver installed and tested, so you can begin flying within moments of unboxing.
- Spektrum 2.4GHz DSMX Technology — The integrated receiver features industry-leading 2.4GHz DSMX digital frequency-hopping technology, ensuring secure, lag-free control and compatibility with any full-range 5+ channel Spektrum DSMX or DSM2 compatible transmitter.
- Scale Finish with Authentic Details — The factory-finished airframe features simulated flying wires and a hand-painted pilot figure wearing a traditional flying scarf, capturing the charm and character of the Golden Age of Aviation.
- Available in Two Colour Options — Choose between a vibrant fully-painted yellow scheme or a lighter-weight unpainted white base version, depending on your aesthetic preference and desired weight characteristics.
- Compact Ultra-Micro Design (550mm Wingspan) — At 550mm wingspan and 418mm length, the UMX WACO is small enough to fly safely indoors in large spaces such as school gymnasiums, halls, and aerodromes, yet large enough to provide a satisfying flying experience and visible scale detail.
Technical Performance
The E-flite UMX WACO is engineered with precision and attention to performance detail. The aircraft features a Spektrum brushless outrunner motor rated at 1208–1900Kv with 10-pole construction, paired with a matching brushless ESC integrated into the control unit. This power system has been specifically tuned for both 2S and 3S operation, allowing you to optimise your flying experience based on your preferences and available battery capacity. With a 2S 7.4V 280–300mAh LiPo, you'll experience performance characteristics similar to the original model—ideal for smooth, controlled flying and extended flight times. When you upgrade to a 3S 11.1V 300mAh LiPo, you unlock dramatically increased speed and unlimited vertical performance, transforming the aircraft into a more spirited performer capable of impressive aerobatic sequences. The motor is paired with a 5.75 x 2.50 propeller optimised for this power envelope. All four control surfaces are actuated by Spektrum linear servos that provide precise, responsive control input with excellent centering and reliability. The airframe construction uses advanced EPS (expanded polystyrene) material throughout, delivering a lightweight yet surprisingly durable structure that can withstand the occasional impact or hard landing whilst maintaining structural integrity. At 119 grams with the recommended battery installed, the UMX WACO sits comfortably under the 250-gram threshold, making it practical and accessible for a wide range of flying locations. The biplane configuration, with its two sets of wings, provides natural stability and a distinctive silhouette that captures the essence of 1930s aircraft design. Despite its compact size, the aircraft's lightly loaded design ensures predictable handling characteristics and responsive control feel that belies its diminutive dimensions.
What's in the Box
- E-flite UMX WACO airframe, 550mm wingspan, fully assembled
- Four Spektrum linear servos (pre-installed)
- Spektrum brushless outrunner motor, 1208–1900Kv, 10-pole (pre-installed)
- Spektrum control unit with integrated brushless ESC and 2.4GHz DSMX receiver (pre-installed)
- UMX WACO 550mm product manual with setup and flying instructions
What You Need to Complete
- Full-range 5+ channel Spektrum DSMX or DSM2 compatible transmitter (sold separately)—Spektrum models including the DXS and other AirWare-equipped transmitters are suggested for telemetry compatibility
- One 2S 7.4V or 3S 11.1V 280–300mAh LiPo battery with JST-RCY connector (or JST-PH connector plus suitable JST-RCY to JST-PH adapter, sold separately)
- Compatible LiPo battery charger (sold separately)
Frequently Asked Questions
- What is the skill level required to fly the E-flite UMX WACO? — This aircraft is rated as Skill Level 2, suitable for RC pilots who already have some experience flying similar models. It is not recommended as a first-ever RC aircraft or as a next step after a trainer model. You should have previous experience flying higher-performance ultra-micro models such as the UMX Timber series, or larger models such as the T-28 Trojan 1.1m or Timber 1.5m before attempting to fly the WACO. However, the inclusion of optional-use SAFE Select does provide helpful flight envelope protection that can assist as you familiarise yourself with the aircraft's handling characteristics.
- Can I fly the UMX WACO indoors? — Yes, the ultra-micro size and 550mm wingspan make this aircraft ideal for indoor flying in large spaces such as school gymnasiums, aerodromes, and aircraft hangars. The lightweight EPS construction and lightly loaded biplane design ensure gentle, controllable flight characteristics in enclosed environments. However, you should always check local regulations and obtain permission before flying indoors, and ensure the space is clear of obstacles and spectators.
- What battery does the UMX WACO require, and what are the differences between 2S and 3S operation? — The aircraft is compatible with either a 2S 7.4V 280–300mAh LiPo battery or a 3S 11.1V 300mAh LiPo battery, both with JST-RCY connectors (or JST-PH with an adapter). With 2S batteries, you'll experience similar performance to the original model—smooth, controlled flight with extended flight duration. With 3S batteries, you'll enjoy increased speed and unlimited vertical performance, making the aircraft more aerobatic and spirited. Choose 2S for relaxed, scale-like flying or 3S for more dynamic performance.
- What transmitter do I need to fly the UMX WACO? — You need a full-range 5+ channel Spektrum DSMX or DSM2 compatible transmitter. Spektrum transmitters including the DXS, DX6e, DX8e, DX9, NX6 through NX20, and iX12 through iX20 are all compatible. Models with AirWare compatibility will also receive real-time battery voltage telemetry during flight. You can use this aircraft with many existing Spektrum transmitters if you already own one.
- What is AS3X technology, and how does it improve my flying experience? — AS3X (Artificial Stabilization–3-aXis) is Spektrum's exclusive technology that continuously monitors the aircraft's attitude on all three axes and makes micro-adjustments to control surfaces to smooth out the effects of wind and turbulence. This means the aircraft feels locked-in and stable, handling like a much larger, expertly tuned model even in challenging flying conditions. AS3X works automatically in the background and requires no pilot input or setup—it's simply always working to improve your control feel and stability.
- What is SAFE Select, and how does it help me fly the WACO? — SAFE Select is an optional-use flight envelope protection system that you can toggle on and off in flight using a transmitter switch. When enabled, it provides pitch and bank angle limits that prevent excessive attitudes, automatic self-levelling that returns the aircraft to level flight when the sticks are centred, and ensures the wings remain level during takeoffs and landings. This system requires no complex programming—channel 5 (Gear) is automatically assigned on most Spektrum transmitters. It's particularly helpful for building confidence as you learn to fly this model.
- Is the UMX WACO suitable for outdoor flying? — Yes, the aircraft is capable of outdoor flying in suitable spaces including yards, parks, sports fields, and open areas. The brushless power system and modern flight electronics make it responsive and controllable in outdoor conditions. However, you should consider wind conditions carefully—whilst AS3X stability helps in moderate turbulence, very strong winds may prove challenging due to the aircraft's lightweight ultra-micro design. Always choose calm to light wind conditions for optimal flying experience.
- What is the flight time I can expect from the UMX WACO? — Flight time depends on battery capacity and power settings. With a 2S 280–300mAh battery, you can expect approximately 5–8 minutes of flight, whilst a 3S 300mAh battery typically provides similar duration despite the increased performance capability, as the higher voltage allows for less throttle application during normal flying. Multiple batteries allow you to extend your flying session significantly.
- Does the UMX WACO come with a transmitter and battery? — No, the aircraft is sold as Bind-N-Fly Basic, meaning it comes with all airframe components, servos, motor, ESC, and receiver pre-installed and ready to bind, but you must supply your own transmitter and battery. This allows you to use your existing Spektrum transmitter if you already own one, and choose the battery capacity and type that suits your preferences.
- What spare parts are available for the UMX WACO? — E-flite offers a comprehensive range of replacement and upgrade parts including battery hatches in both yellow and white, wing sets, tail sets, landing gear sets, and fuselage components. This means if you sustain damage that can't be repaired, you can easily restore the aircraft to like-new condition with genuine replacement parts available through authorised retailers like RC Model Shop.
- How does the brushless power system compare to brushed motors? — The brushless motor used in the UMX WACO offers superior efficiency, longer lifespan, and more consistent power delivery compared to brushed motors. Brushless systems require less maintenance, produce less electrical noise interference with the radio receiver, and deliver more usable power from your battery. The 1208–1900Kv brushless outrunner motor in the WACO provides excellent throttle response and smooth power characteristics across its entire operating range.
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 UMX WACO BNF Basic with AS3X and SAFE Select, Yellow A-EFLU53550Y 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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