I also hear that whoop sound on lot of G.E. locomotives especially Amtrak, it’s pretty cool!
Go Amtrak and CSX!
Thanks Grandma and Granddad for your support and inspiration!
Sounds like a compressor starting up to me.
Yup…
Brilliant subject line by the way…
if I remeber correctly what you are hearing is the air compressor kicking in. The whoop is sometimes followed by I guess you could call it a pounding, not really sure what to call it.