I downloaded B52 from b-52g_rrv_jt to fly on FSX. Is all ok, except the speed hold on autopilot:
Holding Altitude or HDG is ok, but not the speed. I noted that autothrottle is available without any arming, but the speed is always increasing without any limit.
There is perhaps some improvement I have not loaded?
Please, excuse my poor English
See if the gauge you want is in here.