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S139

S139 is ISRO’s composite solid rocket motor used as the PSLV first-stage core motor; the PSLV-XL configuration adds six extended solid strap-on motors around the core.

Identity

Aliases
S-139PS1 S139
Domains
spaceflight
Identity Level
model
Kind
solid-rocket-motor
Name
S139
Status
active

Details

Description
S139 is ISRO’s composite solid rocket motor used as the PSLV first-stage core motor; the PSLV-XL configuration adds six extended solid strap-on motors around the core.
Propellants
HTPB

Links

Assets & Meta

Creation Time
August 13, 2026 at 22:29:29 UTC
Updated Time
August 13, 2026 at 22:29:29 UTC

Other

Sources
  • Note
    ISRO identifies PS1 as the first stage and names the S139 solid rocket booster containing 139 tonnes of HTPB; it also distinguishes PSLV-XL, QL, DL, and CA strap-on counts.
    Publisher
    Indian Space Research Organisation
    Title
    Polar Satellite Launch Vehicle (PSLV)
  • Note
    ISRO identifies the four-stage PSLV architecture and six PSOM-XL strap-on motors for the XL configuration.
    Publisher
    Indian Space Research Organisation
    Title
    PSLV-C11 / Chandrayaan-1