Key Features
- High speed
- Low cost
- Low deadband
- Digital precision
- Metal gears
Overview
This 0.10-second transit time (at 6 volts), 28 oz-in of torque, metal gear servo is an ideal combination of weight, speed and holding power for slow and park flyer aircraft. Ball bearing support around the output shank helps keep the servo precise for many flights to come.
Choose the A3040 servo for electric aircraft and sailplanes where the robust nature of metal gears is desired. The low deadband technology means that you’ll enjoy reliable accuracy and precision.
Detailed Information
Click Here to see Spektrum's Servo Reference Chart
- Brand: Spektrum
- Model Number: SPMSA3040 (P-SPMSA3040)
- Servo Type: Digital sub-micro aircraft servo
- Servo Size Category: Sub-Micro
- Gear Type: Metal
- Material: Plastic housing with metal gears
- Bearing Support: Single ball bearing around output shank
- Operating Voltage Range: 4.8V to 6.0V
- Torque @ 4.8V: 23 ounces-inches (1.66 kilogram-centimetres)
- Torque @ 6.0V: 28 ounces-inches (2.0 kilogram-centimetres)
- Speed @ 4.8V: 0.12 seconds per 60-degree arc
- Speed @ 6.0V: 0.10 seconds per 60-degree arc (transit time)
- Weight: 0.44 ounces (12.6 grams)
- Height: 1.0 inch (25 millimetres)
- Length: 0.93 inches (23.6 millimetres)
- Width: 0.45 inches (11.5 millimetres)
- Programmable: No
- Water-Resistant: No
- Application: Air (aircraft)
- Key Features: High speed, low cost, low deadband, digital precision, metal gears, ball bearing support
- Ideal For: Electric aircraft, sailplanes, slow flyers, park flyers
- Includes: Servo unit with standard connector lead
Overview
The Spektrum A3040 Sub-Micro Digital High Torque Metal Gear Aircraft Servo represents an exceptional choice for RC aircraft enthusiasts across the UK seeking a servo that combines speed, strength and reliability in a compact package. This digital precision servo is purpose-built for electric aircraft and sailplanes, delivering the robust performance characteristics that serious modellers demand. Whether you're flying slow and park flyer aircraft or exploring the world of RC flying for the first time, the A3040 offers an ideal balance of weight, speed and holding power that will keep your control surfaces responsive and precise through every flight.
At just 12.6 grams, this sub-micro servo packs impressive capability into a featherweight design that won't compromise your aircraft's performance or balance. The metal gear construction ensures durability and longevity, making it a cost-effective investment for your RC fleet. Ball bearing support around the output shank provides exceptional precision and stability, helping maintain accurate control inputs flight after flight. The combination of high speed response and strong torque output makes the A3040 a trusted choice for modellers who refuse to compromise on quality, whether building competition-grade aircraft or enjoying casual flying with RC planes in the UK.
With low deadband technology delivering digital precision, the A3040 eliminates the sluggish response characteristic of older servo designs. This means tighter control, more predictable handling characteristics, and ultimately more enjoyable flying experiences. The servo operates across the standard 4.8V to 6.0V range, allowing flexibility in your power system design whilst maintaining consistent performance regardless of battery voltage fluctuations during flight.
Key Features
- High Speed Performance — The A3040 delivers an impressive 0.10-second transit time at 6 volts, meaning your control inputs are translated into physical movement almost instantaneously, providing the rapid response required for precise aircraft control and quick reaction to wind gusts or flight corrections.
- Metal Gear Construction — Unlike plastic gear servos that can wear and strip under load, the robust metal gear design ensures durability and longevity, making this servo suitable for extended use across multiple flying seasons without performance degradation.
- Low Cost Without Compromise — The A3040 achieves professional-grade performance at an accessible price point, making it an economical choice for builders adding multiple servos to their RC aircraft projects without breaking their budget.
- Low Deadband Technology — Digital precision servo circuitry minimises the dead zone where servo input produces no output, resulting in tighter, more accurate control authority over your aircraft's control surfaces and eliminating sloppy handling characteristics.
- Digital Precision Control — Advanced digital servo electronics ensure consistent, repeatable servo positioning with minimal deviation, critical for maintaining stable flight characteristics and predictable handling across different flying conditions.
- Ball Bearing Output Support — The output shank is supported by ball bearing assemblies rather than bushings, dramatically reducing wear and maintaining mechanical precision throughout the servo's operational life, ensuring your control inputs remain accurate through hundreds of flights.
- Sub-Micro Compact Size — At just 1 inch in height, 0.93 inches in length and 0.45 inches in width, the A3040 fits perfectly in confined spaces within aircraft fuselages and wing leading edges, ideal for scale models and aircraft where space is at a premium.
- Lightweight Design — Weighing only 0.44 ounces, this servo adds minimal weight to your aircraft, preserving payload capacity and maintaining optimal wing loading for superior flight performance and efficiency.
Technical Performance
The Spektrum A3040 represents the pinnacle of sub-micro servo engineering, delivering specifications that punch well above what you'd expect from such a compact unit. At 6.0 volts, this servo generates 28 ounces-inches (2.0 kilogram-centimetres) of holding torque, sufficient to control even larger control surfaces with authority whilst maintaining the speed required for responsive aircraft handling. Operating across the 4.8V to 6.0V range provides compatibility with both 2-cell lithium polymer batteries and standard alkaline battery packs, giving modellers flexibility in their power system designs. The 0.10-second transit time specification at 6 volts represents genuinely rapid servo actuation — this is the time required for the servo to move its output shaft through a complete 60-degree arc, and at 0.10 seconds, the A3040 is considered a high-speed performer in the sub-micro category. The digital servo electronics utilise precision position feedback to maintain accuracy, with low deadband technology ensuring minimal delay between your transmitter input and physical servo movement. The metal gear drive train is the critical differentiator here, as metal gears resist stripping and wearing far better than plastic alternatives, particularly under the repeated stress of control surface movement during sustained flying. The single ball bearing support around the output shank reduces friction and wear compared to bushing-only designs, meaning your servo will maintain its precision characteristics across hundreds of flight hours. This is a truly professional-grade servo engineered for the discerning RC aircraft enthusiast in the UK who values reliability, speed and longevity.
What's in the Box
- SPM A3040 Sub-Micro Digital High Torque Metal Gear Aircraft Servo
- Standard servo connector lead for receiver compatibility
Frequently Asked Questions
- Is the Spektrum A3040 suitable for my RC aircraft project? — The A3040 is specifically designed for electric aircraft and sailplanes where robust metal gears are desired. Its sub-micro size makes it ideal for scale models, park flyers, and any aircraft where weight is a critical concern. If you're building an RC plane or glider and need reliable, fast control surface actuation, the A3040 is an excellent choice.
- What voltage battery should I use with the A3040 servo? — The A3040 operates across 4.8V to 6.0V, making it compatible with 2-cell lithium polymer batteries (nominally 7.4V but dropping to acceptable levels under load) or 4-cell nickel metal hydride packs. For maximum performance and torque output, 6.0 volts is recommended, though the servo will function properly across the entire voltage range.
- How does the metal gear construction benefit me? — Metal gears are dramatically more durable than plastic gears, resisting wear and stripping even under sustained use. This means your servo will maintain performance characteristics across many flying seasons, ultimately saving you money on replacements and ensuring consistent control authority throughout your aircraft's operational life.
- What makes the low deadband feature important? — Deadband is the range of input where the servo receives a signal but doesn't move. Lower deadband means tighter, more responsive control — your aircraft will feel more connected to your inputs, making flying more enjoyable and precise, particularly when making fine control adjustments.
- Is this servo waterproof or weather-resistant? — The A3040 is not waterproof and does not carry a weather-resistance rating, so it should be protected from moisture. If flying in damp conditions or near water, ensure the servo compartment is sealed appropriately to prevent water ingress.
- How does the ball bearing output support improve performance? — Ball bearings around the output shank create a smoother, more stable pivot point compared to bushing-only designs. This reduces friction, improves mechanical precision, and dramatically extends the servo's lifespan by minimising wear on critical components.
- Can I programme or adjust this servo? — The A3040 is not programmable, meaning it comes with factory-set parameters that cannot be modified. This simplicity is actually an advantage for most users, as it ensures straightforward installation with no configuration complexity.
- What is the difference between this and other sub-micro servos? — The A3040 distinguishes itself through metal gear construction, ball bearing output support, and fast 0.10-second transit time. These features combine to deliver exceptional durability and responsiveness — qualities that justify the investment for serious RC aircraft enthusiasts in the UK.
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 SPM A3040 Mid Torque High Speed SubMicro Servo Metal Gear Aircraft Servo 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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