Longest static fire?

What is the longest duration for a static fire of a complete rocket stage?

Initially I wanted to ask this for Falcon 9 and Falcon Heavy

I found a 10 second static fire for Falcon Heavy - https://spacenews.com/spacex-conducts-falcon-heavy-static-fire-test/

I am asking because the Starship static fire seems very short

Related question - Longest continuous burning chemical rocket engine? where this answer says:

In August 1988 an SSME (Space Shuttle Main Engine; RS-25) was fired on the ground for 2017 seconds; over 33 minutes.

• From the linked question: In August 1988 an SSME was fired on the ground for 2017 seconds; over 33 minutes. Jan 13 at 19:18
• Havent noticed that because the guy asked for non static fire tests Jan 13 at 20:23
• With the existing tags: testing (96 questions) and qualification-testing (9 questions) there was no reason to create a third new tag called test so I've replaced it and added the relevant information that (at)OrganicMarble mentioned. Since comments are considered temporary we should try to move relevant information back into the question.
– uhoh
Jan 13 at 21:32
• I had no idea that I can create new tags, can I get this privilege removed? Jan 13 at 21:38

The success rate of the Saturn V is attributed, among other factors, to the extensive testing, in particular testing beyond the design parameters. The three stages of the Saturn V had the nominal thrust durations:

• S-1C: 160-170 seconds
• S-II: 360-370 seconds
• S-IVB: 450-500 second (combined)

All stages were subjected to full-duration static firing tests, which would make the S-IVB a good candidate. A full-duration static firing test for the S-IVB used on AS-201 (Saturn 1B configuration) took 452 seconds. Before that, a test of S-IV-10, used on a Saturn 1, even lasted 480 seconds.

The engines were routinely fired beyond their nominal thrust durations, but I have not found any evidence that they did this with the stages too.

In March 2021 a full-duration test of the SLS lasted 499.6 seconds to take the record.

Hat tip to @IronEagle.

• Excellent find! Jan 15 at 5:59
• Note: The upcoming final test of the Green Run series (for the SLS) may end up firing the full lower core stage for up to 480 seconds. This is, however, only the core, not including the two boosters. It also may not run for longer than 452 seconds. nasa.gov/exploration/systems/sls/… Currently set to take place on Saturday: nasa.gov/press-release/… Jan 15 at 6:21
• There was a static fire of the S-IV-10 stage for 480 seconds on 1965-01-21: history.nasa.gov/MHR-5/part-6.htm Jan 16 at 21:31
• @IronEagle That is a great find, for other reasons as well!
– Ludo
Jan 16 at 21:46
• The second Green Run test completed today, with a runtime of 499.6 seconds, I think an update in your answer fits best. Mar 18 at 21:30

Longest Static Fire of a rocket engine:
With you showing interest in the SSME firing (which was probably not attached to a full stage), the Glen Research Center operated a xenon gas engine (0.236 N thrust) continuously from 2003 to 2009 (48,000 hours or 5.5 years).

Longest Static Fire of a complete solid-fuel stage:
(See other answer for longest liquid-fuel stage)
In terms of a complete stage, one avenue is solid-fuel stages, as those tend to be tested in full.

• The legendary AJ-260 (an alternative solid-fuel-only Saturn V first stage) had a burn time of 114 seconds, and three test firings were conducted in 1965-67.

• The first stage of the Ariane-6 is currently in development, a solid-rocket motor with test firings of 135-140 seconds.

• The second stage of the OmegA rocket will be the Castor-300, which had a test firing in 2020 which lasted for 139 seconds.

• The second stage of the Athena I and II rockets was the solid-fueled Orbus 21D, with a burn time of 152-156 seconds. A test firing of duration 145 seconds was conducted on 1979-03-16.