Taking the Tricolour to Near Space: Inside Zepto’s High-Altitude Republic Day Mission

On India’s 77th Republic Day, quick-commerce platform Zepto supported a rare and technically ambitious aerospace experiment that took the Indian National Flag to the stratosphere, at an altitude exceeding 100,000 feet. The initiative was led by Soham M Rai, a technology creator and aerospace enthusiast, who documented the project through his Instagram page @zikiguy, known for showcasing high-altitude balloon experiments and near-space explorations. The mission combined scientific precision with symbolic intent, transforming a national celebration into a demonstration of engineering capability.

Why the Stratosphere Was Chosen

The stratosphere occupies a transitional zone between Earth’s atmosphere and outer space. This region lies far beyond commercial aviation routes and the operational limits of drones, which are constrained by aviation regulations. Aircraft, even at their maximum cruising altitude, cannot reach the upper layers of the stratosphere. To overcome these constraints, the team opted for a hydrogen-filled high-altitude balloon, a platform widely used in atmospheric research due to its ability to ascend gradually to extreme heights. Reaching near space allowed the team to place the tricolour against a backdrop where the curvature of the Earth becomes visible, amplifying both the visual and symbolic impact of the unfurling.

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Operating above 30 kilometres presents severe challenges. Temperatures in the stratosphere can fall below minus 60 degrees Celsius, and air pressure drops dramatically. To function reliably under these conditions, the payload required careful engineering and rigorous testing. The payload consisted of the folded Indian National Flag, GPS tracking systems, onboard cameras, and a recovery mechanism. Lightweight materials were used to ensure the balloon could lift the payload efficiently, while thermal insulation protected sensitive electronics from freezing temperatures.

Launch Preparation and Ascent

The launch involved several hours of preparation. Weather conditions were closely monitored, systems were tested repeatedly, and airspace coordination was carried out to ensure regulatory compliance. Once clearance was obtained, the balloon was released and began its steady ascent through multiple layers of the atmosphere. As the balloon rose, onboard instruments tracked altitude, temperature, and location, while cameras recorded the journey. The ascent proceeded as planned, with the flag unfurling at the designated altitude.

One of the most critical aspects of the mission was ensuring that the flag could unfurl without any manual intervention. At such altitudes, real-time communication is unreliable, making automation essential. Instead of relying on mechanical motors—which often fail in extreme cold—the team designed an altitude-triggered thermal release system.

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Once the payload reached a predetermined height of approximately 80,000 feet, the controlled heat activated the release mechanism, allowing the flag to unfold smoothly. This approach reduced mechanical complexity while ensuring precise deployment timing.

Contrary to common assumptions about high-altitude balloon missions, the balloon did not burst after reaching its maximum altitude. Instead, after completing the mission objectives, the system transitioned into descent. During this phase, tracking signals weakened temporarily, creating uncertainty about the payload’s location. However, the payload ultimately landed intact and was successfully recovered. Examination of the onboard footage confirmed that the Indian National Flag had unfurled fully in the stratosphere, meeting the mission’s primary objective.

Impact and Broader Significance

Beyond its visual appeal, the project highlighted the growing role of individual innovators and private companies in scientific experimentation. Zepto’s support enabled the initiative to reach a wider audience, while Soham M Rai’s Instagram page offered transparency into the process, explaining the technical challenges and decisions involved. By taking the Indian National Flag to the edge of Earth’s atmosphere, the mission demonstrated how science and symbolism can intersect to create moments of lasting national significance.