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I think there are many baffles inside the shape of Fuel tank. What kind of advantage they do? Do they help in managing the oscillations in-flight?

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marked as duplicate by Simon, mins, aeroalias, Deer Hunter, fooot Oct 30 '15 at 14:27

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They help in keeping the fuel from sloshing around during maneuvering. Some sloshing is impossible to avoid, but a reduction is extremely helpful in avoiding unwanted dynamics.

Consider a sudden pitch-up into a climb, or a sudden acceleration when the afterburners are lit: Now the fuel will rush backwards, shifting the center of gravity backwards. If this happens suddenly and the fuel starts oscillating, the aircraft would fly a wavy flightpath without pilot input. Now add the input of the pilot who tries to keep the flightpath steady, which is delayed by maybe 0.2 seconds, and add the latency of the control system, and you might have ideal conditions for pilot induced oscillations.

Some combat aircraft don't use baffles, but a coarse, sponge-like foam which takes up maybe 2% of the tank volume but dampens fuel oscillations very effectively.

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  • $\begingroup$ +1 for that last part. Where can I read more about this sponge foam? $\endgroup$ – DrZ214 Feb 25 '16 at 1:36
  • $\begingroup$ @DrZ214: I only know it is from a Belgian company and used in the MRCA Tornado. Any open-cell foam which is not dissolved by aviation fuel should work. $\endgroup$ – Peter Kämpf Feb 25 '16 at 22:30

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