Overview
The Polar Satellite Launch Vehicle (PSLV) is a four-stage expendable rocket developed and operated by the Indian Space Research Organisation (ISRO). Designed primarily to deliver Earth observation satellites into Sun-synchronous polar orbits (SSO), the PSLV has become India's most reliable and versatile launch vehicle — with over 60 flights since its first successful mission in 1994 (after an initial failure in 1993) and a consecutive success streak exceeding 50 missions.
Despite its relatively modest payload capacity compared to larger international launchers, the PSLV has achieved remarkable feats — including launching India's first lunar probe (Chandrayaan-1), Mars orbiter (Mangalyaan) and navigation satellites (NavIC/IRNSS), as well as a record 104 satellites on a single mission in February 2017.
Specifications — PSLV-XL
| Parameter | Value |
|---|---|
| Height | 44 m (144 ft) |
| Mass at liftoff | ~320,000 kg (PSLV-XL) |
| Stages | 4 (alternating solid and liquid) |
| Stage 1 | S139 solid motor (one of the largest in the world) + 6 solid strap-on boosters |
| Stage 2 | Vikas liquid engine (UDMH/N₂O₄) |
| Stage 3 | S7 solid motor |
| Stage 4 | 2 × L-2-5 liquid engines (MMH/MON-3, restartable) |
| Payload to SSO (600 km) | ~1,750 kg |
| Payload to LEO | ~3,800 kg |
| Payload to GTO | ~1,425 kg |
| Launch site | Satish Dhawan Space Centre, Sriharikota, India |
Variants
The PSLV flies in three main configurations, differing in the number and size of strap-on boosters:
- PSLV-CA (Core Alone) — no strap-on boosters. Used for lighter payloads. Lowest cost variant.
- PSLV-DL — two strap-on boosters. Intermediate capacity, introduced in 2019.
- PSLV-XL — six extended strap-on boosters (larger PSOM-XL motors). The most powerful configuration and the most commonly flown variant. Used for Chandrayaan-1, Mars Orbiter Mission and NavIC satellites.
- PSLV-QL — four strap-on boosters. Introduced for specific payload requirements.
Notable Missions
| Date | Mission | Significance |
|---|---|---|
| Oct 2008 | Chandrayaan-1 | India's first lunar mission. Discovered water molecules on the Moon's surface — a landmark scientific finding. |
| Nov 2013 | Mars Orbiter Mission (Mangalyaan) | India became the first Asian nation to reach Mars orbit — and did so on its first attempt. The mission cost approximately $74 million, less than the budget of many Hollywood films. |
| Feb 2017 | PSLV-C37 | Deployed 104 satellites on a single flight — a world record at the time. Payloads from 7 countries. |
| 2013–2018 | NavIC/IRNSS | PSLV launched all seven satellites of India's regional navigation constellation. |
| Aug 2023 | Chandrayaan-3 | Launched by ISRO's heavier LVM3 — but the programme's heritage traces directly to PSLV-launched Chandrayaan-1. |
PSLV Orbital Platform (POEM)
In a creative reuse of spent hardware, ISRO has begun converting the PSLV's spent fourth stage into a PSLV Orbital Experimental Module (POEM) — an orbital platform that hosts technology demonstration payloads in orbit for weeks or months after primary payload deployment. This gives the fourth stage a second life as a micro-satellite platform, generating additional mission value from hardware that would otherwise be orbital debris. Several POEM experiments have been conducted, and the concept has attracted interest from international researchers.
Future: PSLV and Beyond
ISRO continues to fly the PSLV regularly for Indian government missions and commercial rideshare payloads (marketed through its commercial arm, NewSpace India Limited / NSIL). Looking ahead, ISRO's Small Satellite Launch Vehicle (SSLV) is designed to complement the PSLV for lighter payloads with faster turnaround, while the heavier LVM3 (formerly GSLV Mk III) handles GEO and beyond. A next-generation reusable launch vehicle (RLV-TD) is also under development, though it remains in early testing as of 2026.