Most cargo rockets, such as Falcon 9, Delta IV, and many others, incorporate payload fairings to protect payloads from aero forces and heating during ascent. All of these rockets' fairings split in two upon separation. Have there been any fairings which split into more than two pieces?

From Wikipedia, the Delta IV has a trisector fairing but I don't have any evidence about how it works.

The aluminum trisector (three-part) fairing was built by Boeing and derived from a Titan IV fairing. The trisector fairing was first used on the DSP-23 flight. The Delta IV with the extended fairing is over 62 m (203 ft) tall.

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    $\begingroup$ Not a cargo fairing as such, but the Apollo missions had the four-part Spacecraft-Lunar Module Adapter which, among other things, served as a shroud for the LM during launch. $\endgroup$
    – Cadence
    Commented Sep 30, 2022 at 19:56

1 Answer 1


My kneejerk reaction on this was incorrect, the "trisector fairing" does split into three parts.

After climbing into the rarefied upper layers of the atmosphere, the Delta 4 will release its nose cone to shed weight and reveal the NROL-44 payload. The trisector fairing, designed especially to accommodate large NRO and military satellites, will jettison from the launcher in three pieces rather than in two halves like payload shrouds used on most other other rockets.

A ULA video is embedded, this still from the animation shows the fairing in 3 parts.

enter image description here

Source https://spaceflightnow.com/2020/08/26/delta-4-heavy-likely-heading-for-geosynchronous-orbit-with-top-secret-payload/

A trisector fairing was also used on Titan IVs for large defense payloads and at least one NASA payload, Cassini. This schematic shows the 86 foot fairing used for Cassini in a test configuration.

enter image description here


  • $\begingroup$ Are there any other LVs which use 3 or more fairing pieces? $\endgroup$
    – WarpPrime
    Commented Sep 30, 2022 at 21:03
  • $\begingroup$ I read that the Titan IV did but I have not yet confirmed it @fasterthanlight $\endgroup$ Commented Sep 30, 2022 at 21:07
  • $\begingroup$ @fasterthanlight I found a reference for the Titan IV trisector fairings. $\endgroup$ Commented Sep 30, 2022 at 22:57
  • $\begingroup$ Funny they have the whole upper stage in the fairing $\endgroup$
    – Antzi
    Commented Oct 1, 2022 at 8:29
  • $\begingroup$ @Antzi I asked why that was a while back, never got a definitive answer space.stackexchange.com/q/33255/6944 $\endgroup$ Commented Oct 1, 2022 at 11:27

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