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I was reading about the Minotaur V that Orbital Sciences is readying for launch from Wallops Island, VA before 2014. (I really do not trust launch dates).

It is a Minotaur IV+ with a fifth stage. Ok, it is an all solids launcher, based off the Peacekeeper ICBM motors, so I get the extra staging.

Shuttle is hard to quantify in terms of stages, sort of 1.5 stages (SRB's, ET, and shuttle, but engines are on the shuttle, ET is just a tank.)

Early Atlas that dropped two engines and tankage, but kept a sustainer engine firing is another half stage approach.

Falcon 9 is easy with 2 stages (maybe 3 with Dragon).

Saturn V was mostly four stages (counting the SM/CM combo sort of as a stage).

Has there ever been a real launcher (that launched, not paper designs) with more stages? (Seems like the Soviet N1 should count as real, since they tested a physical rocket, even if it never succeeded).

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  • $\begingroup$ geoffc : If you want to count CSM as a stage, please add LM. $\endgroup$ – Deer Hunter Aug 7 '13 at 19:29
  • $\begingroup$ @DeerHunter So LM is a great example that breaks the rule. It does not contribute to the initial launch. So by that thinking, the SM does not either. The S-IV stage did the TLI. And SM does TEI on the way back. $\endgroup$ – geoffc Aug 7 '13 at 19:34
  • $\begingroup$ The Soviet N1 Rocket (intended for a moonshot) was a 5 stage design too. en.wikipedia.org/wiki/N1_%28rocket%29 $\endgroup$ – Dan Neely Aug 7 '13 at 20:08
  • $\begingroup$ I think you need to define more clearly what counts as a stage, but the list of possible candidates shouldn't neglect to include Titan IV with up to 5 stages, and Proton with 3-4, but up to 6 RD-253 boosters attached to stage 1. ;) $\endgroup$ – TildalWave Aug 7 '13 at 20:39
  • $\begingroup$ @TildalWave I agree, stage definition is hard, I am thinking leave up to the answer to define it. Atlas that dropped tanks along the way 1 stage? 1.5? $\endgroup$ – geoffc Aug 7 '13 at 21:20
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If, counting a stage as a unit of a craft that fires, providing thrust, and all thrust cuts off before a different unit in the craft starts to thrust...

The Saturn V - Apollo - LEM stack is 6 stages. The Saturn stack of 3 stages, plus the 2 stages of the LEM, and the single stage CSM pairing. In sequence: Saturn stage I, Stage II, and Stage III, then the CSM, then the LEM Descent, then the LEM ascent, then back to the CSM. The LEM is part of the whole package, and is an important part of the mission to the moon. In those early Apollo launches, the LEM was the real payload, not the CM; the CM was there to keep the LEM weight down... so that astronauts would not be stranded on the moon.

(Later Apollo missions to LEO used the Saturn 1B, itself 2 stages, plus the CSM.)

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  • $\begingroup$ I hear you, but I feel a quibble coming that I cannot fully actualize about counting the LEM. And the Descent/Ascent as two more stages. What about SM, for TEI then? $\endgroup$ – geoffc Aug 7 '13 at 21:57
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    $\begingroup$ There's a difference between a "module" and a "stage". The "service module" has a rocket motor, while the "command module" does not; it's just an environmental compartment unlike virtually any other module of the Saturn V/Apollo vehicle. The Saturn V itself is three stages: five F1 liquid motors (S-1), then five J-1 liquid motors (S-2), the two in combination being enough for LEO, then a single J-2 engine in the S-IVB (S-B) third stage that would break LEO and head out to the moon, carrying the LEM and CSM. $\endgroup$ – KeithS Aug 7 '13 at 22:57
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    $\begingroup$ The CSM would then separate, dock with the LEM stored underneath it, then as this pair reached the moon, the CSM's SPS would fire to settle into a stable orbit of the moon (instead of slingshotting around). The LEM would separate, use the DPS "descent stage" to land, the APS "ascent stage" to return, then the CSM's SPS would fire to break lunar orbit and return home. Ideally, the firing of the SPS to break lunar orbit is the last time a "main engine" on any part of the Apollo vehicle fires. $\endgroup$ – KeithS Aug 7 '13 at 23:03
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    $\begingroup$ So, call it six independent stages of disposable rocket motors, used in seven "phases" of the Apollo mission requiring some part of the vehicle to speed up or slow down using rocket thrust: Launch, LEO, LEO departure, lunar capture, LEM descent, LEM ascent, lunar orbit departure. The final phase, re-entry deceleration, is accomplished using the Earth's atmosphere as most of our space vehicles do. $\endgroup$ – KeithS Aug 7 '13 at 23:06

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