What makes Skyroot’s Vikram-1 launch unique? | Explained
Skyroot Aerospace's Vikram-1, a four-stage small-satellite launch vehicle, lifted off from the Satish Dhawan Space Centre in Sriharikota on its debut flight, called Mission Aagaman
The vehicle's liquid-fuelled upper stage injected its payload into a roughly 450 km low Earth orbit (LEO) about 15 minutes after liftoff
The mission carried two cubesats — one built by Skyroot itself and another by fellow Indian startup Grahaa Space
The flight made India the third country where a privately built rocket has independently placed a payload in orbit, after the United States and China
Orbital vs Suborbital Spaceflight
A suborbital flight follows a ballistic arc that reaches space (crossing the Kármán line, the internationally recognised 100 km boundary of space) but falls back to Earth without completing a full revolution, because it never attains orbital velocity. An orbital flight injects the payload at a velocity high enough (roughly 7.8 km/s at LEO altitudes) that gravity's pull is balanced by the vehicle's forward speed, allowing it to continuously "fall around" the Earth instead of falling back onto it.
Key Details
- Kármán line: internationally accepted edge of space at ~100 km altitude
- Low Earth Orbit (LEO): roughly 160 km to 2,000 km altitude; orbital velocity needed is approximately 7.8 km/s
- Skyroot's earlier vehicle, Vikram-S, was a suborbital demonstrator that flew in November 2022 and did not attempt to place a payload in orbit
- Reaching and sustaining orbit requires precise velocity, direction, and altitude control at engine cutoff — far more demanding than a suborbital lofting trajectory
Vikram-1's achievement lies specifically in crossing from suborbital demonstration (Vikram-S, 2022) to genuine orbital insertion, which is the technical threshold that separates a "space-reaching" rocket from an operational orbital launch vehicle.
Mixed Solid-Liquid Propulsion Architecture
Vikram-1 uses a four-stage design in which the first three stages are solid-propellant motors (the Kalam series, including the first-stage Kalam-1200 motor) and the final "kick stage" uses a liquid-propellant engine (Raman-I) for precise orbital insertion and circularisation. Solid motors are simpler, more storable, and provide high initial thrust, while liquid engines allow throttling, multiple restarts, and fine velocity control — essential for placing a payload accurately into a target orbit.
Key Details
- First three stages: solid propulsion (Kalam-series motors, named after Dr A.P.J. Abdul Kalam)
- Upper stage: liquid-propellant engine (Raman-I, named after C.V. Raman) used for orbital insertion manoeuvres
- ISRO's own PSLV (Polar Satellite Launch Vehicle) uses a similar alternating solid-liquid-solid-liquid, four-stage configuration, showing this is a proven Indian design philosophy for reliability
- Liquid kick stages allow "restart" capability, useful for multi-satellite deployment into different orbital planes
The liquid Raman-I kick stage is what allowed Vikram-1 to convert a solid-motor-powered ascent into a stable, circularised 450 km orbit rather than a suborbital arc.
Additive Manufacturing (3D Printing) in Rocket Engines
A defining feature of India's new private launch vehicle developers is the use of metal 3D printing (additive manufacturing) to build rocket engines and structures, replacing components that would traditionally require hundreds of separately machined and welded parts. This reduces manufacturing time, part count, and cost — a key reason "New Space" private players can develop vehicles faster and cheaper than legacy government space programmes.
Key Details
- Skyroot has demonstrated fully 3D-printed cryogenic engines (e.g., the Dhawan-II engine, static-fire tested for 200 seconds) as part of its propulsion technology roadmap
- Rival Indian private player Agnikul Cosmos is separately developing a semi-cryogenic, fully 3D-printed engine for its own launch vehicle
- Globally, SpaceX has used 3D-printed components (such as SuperDraco engine parts) to cut production timelines
- 3D printing enables carbon-composite and modular vehicle designs, both used across Skyroot's rocket family
The propulsion and structural technologies validated in ground tests over the past few years fed directly into Vikram-1's flight-proven design, making additive manufacturing a testable "how" behind India's private orbital breakthrough.
India's Small Satellite Launch Vehicle (SSLV) vs Private Launch Vehicles
ISRO developed its own Small Satellite Launch Vehicle (SSLV) to serve the growing smallsat launch market with a lower-cost, quick-turnaround government-built rocket. Vikram-1 targets the same market segment but as a fully private venture, illustrating how India's space sector reforms have created parallel government and private tracks for smallsat launches rather than a single monopoly provider.
Key Details
- SSLV: three solid stages plus a liquid Velocity Trimming Module; designed to carry up to ~500 kg to 500 km Sun-Synchronous Orbit
- Vikram-1: four stages (three solid plus a liquid kick stage); carries roughly 350 kg to LEO
- Both vehicles are assembled/launched from the Satish Dhawan Space Centre, Sriharikota
- Private access to the same range and ISRO facilities is enabled through authorisation and range-support arrangements under India's post-2020 space reforms
Vikram-1's flight demonstrates that India's smallsat launch capacity is no longer solely dependent on ISRO's SSLV, giving satellite operators a second, commercially operated Indian launch option.
- Vehicle: four-stage rocket, approximately 20 metres tall and 1.7 metres in diameter
- Payload capacity: approximately 350 kg (about 770 lb) to Low Earth Orbit
- Orbit achieved on debut flight: approximately 450 km LEO, reached about 15 minutes after liftoff
- First three stages: solid propulsion (Kalam-series motors); upper stage: liquid propulsion (Raman-I engine)
- Mission name: "Aagaman" (Sanskrit for "arrival")
- Skyroot Aerospace: founded 2018, headquartered in Hyderabad; first suborbital flight (Vikram-S) flown in November 2022
- India becomes the third country with independent private orbital launch capability, after the United States (SpaceX Falcon 1, first success September 28, 2008) and China (iSpace's Hyperbola-1, first success July 25, 2019)