Views of the F-1 injector plate with baffles

This is a follow up question to "Organic Marbles" answer to my earlier question about the atlas rocket exhaust nozzle, regarding the Apollo F1 thrust nozzles having metal baffles/fins inside to prevent the exhaust from spinning around inside the nozzle and exploding the engine/rocket.

My question is, were the nozzle exhaust pipes on the Atlas rocket engines, and the baffles installed inside of the F1 nozzles of the Saturn V first stage, dealing with the same issues of safely venting exhaust gases away from the rocket, or are they different issues.


The baffles on the F-1 and other engines such as early versions of the SSME (described here) are intended to prevent the occurrence of high-frequency combustion instability in the engine's combustion chamber. Uncontrolled combustion instability can destroy an engine due to

excessive vibration force (which may break engine parts) or excessive heat transfer (which may melt engine parts).

(from Rocket Propulsion Elements, Sutton, 4th edition, p. 257)

The Atlas turbopump discharge duct described in the linked question is dealing with a different problem, namely keeping flammable gas from accumulating under the rocket.

Two different problems with two different solutions.

  • 1
    $\begingroup$ Thank you again. It proves the point that the only stupid question,is the one not asked. Sorry about referring to you as organic matter. That's what I get for not reading thoroughly. Thank you Organic Marble. :) $\endgroup$ – Ray G Feb 9 '20 at 19:57
  • 3
    $\begingroup$ "organic matter" in the injector plate had me baffled ;) $\endgroup$ – amI Feb 9 '20 at 21:11
  • 1
    $\begingroup$ @aml Appropriate use of "baffled" as well! $\endgroup$ – Organic Marble Feb 9 '20 at 21:12

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.