From Backyard Project to the Skies: How an Essex Engineer Built a Four-Seater Family Aircraft During Lockdown

The dream of personal flight often remains a distant aspiration for most, relegated to the realm of expensive hobbies or commercial travel. However, for Ashok Aliseril Thamarakshan, a mechanical engineer based in Essex, England, the transition from observer to aviator—and eventually to aircraft manufacturer—was a journey defined by technical ingenuity, familial support, and the unique circumstances of a global pandemic. Over the course of 18 months, Aliseril transformed his suburban backyard into a makeshift hangar, meticulously assembling a high-performance four-seater aircraft that would eventually carry his family across the European continent. This feat not only highlights the possibilities of modern kit-built aviation but also underscores a growing trend toward shared ownership and the democratization of private flight.

The Catalyst for Construction

Aliseril’s interest in aviation was dormant until approximately a decade ago, when he moved to a residence situated near a local airfield in the United Kingdom. The constant sight and sound of light aircraft sparked a curiosity that remained unfulfilled until his wife, Abhilasha, gifted him a 30-minute introductory flight experience for his birthday. That brief excursion proved transformative. During his first formal lesson, Aliseril flew to the Isle of Wight, an experience he described as an "eye-opener" regarding the logistical freedom provided by personal aviation.

By 2019, Aliseril had successfully obtained his Private Pilot’s License (PPL). He initially followed the traditional path of renting aircraft for short-distance excursions. However, as a father of two young daughters, Tara and Diya, he quickly encountered the limitations of the general aviation rental market. Most readily available aircraft for hire are two-seater trainers, such as the Cessna 150 or Piper Tomahawk, which were insufficient for a family of four.

When Aliseril explored the secondary market for four-seater aircraft, he was met with a dilemma. Most affordable options were manufactured in the 1960s and 1970s. For a mechanical engineer, the prospect of transporting his family in a decades-old machine with unfamiliar maintenance histories was unappealing. He sought modern safety features, updated avionics, and long-term reliability—criteria that led him to the burgeoning industry of amateur-built aircraft kits.

Selecting the Sling TSi: A Technical Overview

After extensive research into self-assembly kits, Aliseril identified the Sling TSi, a four-seater aircraft produced by the South African manufacturer Sling Aircraft. The TSi (Turbocharged, Sport, Injection) offered a compelling blend of performance and efficiency that rivaled or exceeded older certified aircraft.

In January 2020, just weeks before the onset of global travel restrictions, Aliseril traveled to the Sling Aircraft factory in Johannesburg. The trip was designed to vet the aircraft’s handling characteristics and build quality. Impressed by its performance, he placed an order for the first components of the kit. The timing was providential; as the first crates arrived in the UK, the nation entered its first COVID-19 lockdown, providing Aliseril with the unexpected resource of time.

The Sling TSi is a modern, low-wing aircraft constructed primarily of aluminum. It features a Rotax 915 iS engine—a turbocharged, 141-horsepower powerplant known for its high power-to-weight ratio and fuel efficiency. With a cruise speed of approximately 145 to 155 knots (roughly 167 to 178 mph) and a range of 1,389 kilometers (750 nautical miles), the aircraft is specifically designed for cross-country touring.

The Chronology of a Backyard Build

The construction of an aircraft is a monumental undertaking that requires rigorous adherence to technical specifications and regulatory oversight. Aliseril’s process can be broken down into several distinct phases:

1. Preparations and Early Assembly (April 2020 – September 2020)

Faced with lockdown restrictions that prevented colleagues from assisting, Aliseril constructed a specialized shed in his garden. This environment allowed him to work in close proximity to his home, maximizing his productivity during evenings and weekends. The build began in April 2020 with the tail assembly (empennage), followed by the wings. He noted that while his engineering background provided a foundation, his experience in home improvement and DIY proved equally vital when working with the "IKEA-style" illustrated instructions provided by Sling.

2. Fuselage and Interior (October 2020 – Summer 2021)

The arrival of the fuselage kit marked a significant increase in the project’s complexity. During this phase, the aircraft’s structural core was assembled. Aliseril’s family became integral to the project; his wife assisted with tasks requiring multiple sets of hands, while his eldest daughter, Tara, helped with the meticulous task of removing protective plastic from thousands of aluminum components.

3. Final Assembly and Engine Integration (Late 2021)

As the aircraft outgrew the garden shed, Aliseril moved the components to a professional hangar near Cambridge. This stage involved the "mating" of the wings to the fuselage, the installation of the Rotax engine, and the complex wiring of the avionics suite. The Sling TSi features a modern "glass cockpit," utilizing digital displays rather than traditional analog gauges, requiring precise electrical work.

4. Testing and Certification (January 2022 – May 2022)

Under the regulations of the UK Civil Aviation Authority (CAA), every stage of a home-built aircraft must be inspected by the Light Aircraft Association (LAA). Aliseril underwent approximately 12 formal inspections throughout the build. In January 2022, the aircraft, registered as G-Diya (named after his youngest daughter), was cleared for its maiden test flight.

Regulatory Framework and Safety Standards

The successful completion of G-Diya was a landmark for the UK aviation community, as it was one of the first Sling TSi models built in the country. The regulatory path for such projects is stringent. In the United Kingdom, the LAA acts as the representative body overseeing the airworthiness of amateur-built aircraft.

Unlike the United States, where the Federal Aviation Administration (FAA) categorizes such planes as "Experimental," the UK system requires a "Permit to Fly." This permit is only issued after a series of rigorous ground tests and a flight testing program conducted by an authorized test pilot. During the initial flights, the test pilot subjected G-Diya to high-stress maneuvers to ensure the structural integrity of Aliseril’s work. Aliseril recalled the "psychological step" of transitioning from calling the machine a "project" to calling it an "aircraft" once it had successfully left the ground.

Financial Analysis and Shared Ownership

The cost of building a modern four-seater aircraft is significant, yet Aliseril’s approach offers a blueprint for financial sustainability. He provided a breakdown of the expenses involved:

• The Kit: Approximately £80,000 ($91,000).
• Additional Components: The engine, propeller, avionics (navigation and communication systems), and upholstery brought the total investment to approximately £180,000 ($203,000).

While £180,000 is a substantial sum, Aliseril mitigated the burden through a shared ownership model. He formed a group with three other pilots, splitting the capital and maintenance costs four ways. This reduced the individual investment to roughly the price of a high-end SUV.

Furthermore, the operational costs of the Sling TSi are remarkably low compared to traditional certified aircraft. The Rotax engine consumes approximately 20 liters of unleaded fuel per hour. At current fuel prices, Aliseril notes that the cost of flying is roughly equivalent to the cost of driving a large vehicle, but with the advantage of bypassing traffic and traveling in a direct line at nearly 180 mph.

Broader Impact and Implications for General Aviation

Since receiving its full Permit to Fly in May 2022, G-Diya has become a vessel for family adventure. The Aliseril family has logged over 300 flight hours, traveling to destinations including the Isle of Wight, Skegness, France, and Norway. Their travels are documented on social media, inspiring a new generation of aviation enthusiasts.

Aliseril’s success story carries several implications for the future of general aviation:

• Modernization of the Fleet: The project demonstrates that kit-built aircraft can provide a safer, more technologically advanced alternative to the aging fleet of 20th-century light planes.
• Democratization through Shared Equity: By championing the shared ownership model, Aliseril shows that private aviation can be accessible to middle-income professionals, rather than being restricted to the ultra-wealthy or retirees.
• Educational Value: The project highlights the importance of STEM (Science, Technology, Engineering, and Mathematics) skills. Aliseril hopes his journey encourages more young people to engage in large-scale engineering projects.

As the aviation industry continues to grapple with high costs and environmental pressures, the efficiency and accessibility of the amateur-built sector offer a compelling path forward. For Ashok Aliseril Thamarakshan, the project was never just about the mechanics of flight; it was about creating a legacy of freedom and exploration for his family. In the skies over Europe, G-Diya stands as a testament to what can be achieved when technical expertise is paired with the unwavering resolve of a backyard builder.