[AS-487 T. Headlam]

MKJP-KMIA AAL1376. Leveled off at FL320 .There was a sudden change in the Altimeter. Wind speed suddenly dropped and my Altitude suddenly fell from FL320 to FL170 instantly, Aircraft did not descend. Groundspeed registered at 430 though but my Airspeed was showing 160. Stall horns alarmed. Never could regain altituded and Equipment was rocking back and forth. My trims could not be steady and I am having a bad time keeping her level and stable. Sieara Maestra was my closest Airfield. Step up speed by tipping the nose while trying to play with the A/P. Each time its activated, she gets out of control(Trims). So forget it. Nasty touch but safe on RWY 26. This must be a ASA issue.

vNTSB: Weather related issue.

[AS37 Norm Edwards]

Thanks for the report. Interestingly sudden drops in altitude will almost always be followed up by deactivating the AP and taking manual control, without delay. Perhaps earlier in the drop of altitude in your case with discon the AP could have stopped the shaking. You mentioned an ASA issue? Or did you mean AAS? Can't say I've heard of AAS causing such a situation.

[AS-487 T. Headlam]

Well I did disconnect the A/P because it was thirsting FL350. Once I had little control I needed to open up my GPS for the nearest airfield for a approach. It wasn't easy holding the yoke with the left and throttles and mouse for the GPS with the right. Auto throttles wasn't any help because airspeed was dropping more engaged. She even felt like I lost one of my powerplants.

To me I think this is a ASA(Active Sky Advanced) issue. It must had been the current snapshot of the METAR did not blend in well with updated one.
nice experience though but I hope this doesn't happen again.

[JSkorna]

Could have been the TAT issue we are looking into.