We are using C-130 B and E Models with T-56 A-15 engines and Hamilton Sundstrand 54H60-91/117 propellers. A lot of vibration and resonance are felt on these military version aircraft even after using solid state synchrophasing and conducting prop balancing.

I wanted to know if there is some system to make the aircraft quieter. Except for shutting down the engines of course :)

Are there any resonance controlling items to make the passengers more at ease?

  • 4
    $\begingroup$ Have you tried loudspeakers and AC/DC? $\endgroup$
    – user12007
    May 14, 2018 at 9:59
  • 2
    $\begingroup$ Or noise cancelling headsets for everyone? $\endgroup$
    – CrossRoads
    May 14, 2018 at 12:21
  • $\begingroup$ Line the cabin walls with Sound Proof material, such as aircraftspruce.com/menus/ap/soundproof.html or other similar material approved military use. Of course, the walls may already be lined with something. $\endgroup$
    – CrossRoads
    May 14, 2018 at 16:49
  • $\begingroup$ I really like the "shut down the engine" solution $\endgroup$
    – Manu H
    May 14, 2018 at 21:04
  • 1
    $\begingroup$ I worked the C-130E/H my whole stint in the Air Force. To this day, I have never slept as soundly and as comfortably on an airplane as I did on those birds. When the props are synced, the hum and vibration was so relaxing. I used to string a hammock up from one side to the other and just rock away like a baby. I honestly don’t think there is anything to make it quieter as the military never really cared much about how much noise we were exposed to. $\endgroup$
    – Frank
    May 15, 2018 at 0:15

1 Answer 1


Active vibration control systems exist for some aircraft, though I doubt an ex-military type would have anything off the shelf. There is a system from Lord (the engine mount people) that is intended to counter the vibration from a helicopter main rotor to improve passenger comfort, among other things. This is their claimed reduction:

enter image description here

AVCS Product Brochure

They focus on helicopters but sell components as well, and may be able to customize something that could work for you.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .