The Ah-72 Thunderhead training speed in the Training centre doesn't seem to work, I have invested 31 drill instructors to this bonus and yet the training time does not seem to reduce in the INFO. 

I just upgraded and i checked the time before i started the upgrade and the time after the upgrade and it did not change.

Yes, I cleared my cache and refreshed and browser is refreshed.

http://prntscr.com/f2p1ls

http://prntscr.com/f2p1tb

Testing the next upgrade; I shall post the result when it completes. 

http://prntscr.com/f2p213

http://prntscr.com/f2rpd5

http://prntscr.com/f2rphy

Your exactly right,. the difference is so minimal that it is hard to notice, I see i have reduced it by mere seconds rather than minutes

Thank you again for your help!