DH8 CREW DSNDED BELOW THE MSA AT MDT.

Narrative

AFTER DEVIATING AROUND NUMEROUS TSTMS; IT WAS APPARENT FLT COULD NOT PROCEED TO PHL. DECISION WAS MADE TO DIVERT TO MDT. DURING VECTORS FOR APCH (ILS RWY 31) ADDITIONAL DEVIATING WAS REQUIRED. AT THIS POINT; CAPT INSTRUCTED ME TO MAKE AN ANNOUNCEMENT TO PAX OF DEV; INFORM FLT ATTENDANT AS WELL AS THE COMPANY. AFTER RETURNING TO COM #1 AND STATING TO CAPT I WAS BACK WITH HIM; HE STATED WE WERE CLRED TO 2000 FT MSL AND WERE ON FINAL VECTOR FOR ILS. AT THIS POINT APCH QUESTIONED OUR ALT AND WE STATED LEVELING AT 2000 FT MSL. APCH THEN STATED HE CLRED US TO 3000 FT MSL. CAPT THEN TOOK OVER RADIO AND SAID HE REPEATED 2000 FT BACK TO APCH. WE THEN WERE CLRED TO 3000 FT AND COMPLETED APCH WITHOUT FURTHER INCIDENT. I FEEL THAT THIS INCIDENT WAS CAUSED BY THE FAILURE OF ATC TO NOT CORRECT AN ALT READBACK THAT WAS NOT CORRECT. I ALSO FEEL THAT IT COULD HAVE BEEN A MISTAKE ON EITHER THE APCH CTLR'S; PLT'S; OR ATC'S PART. SINCE I WAS OFF THE FREQ AT THE TIME THE DSCNT CLRNC WAS ISSUED; I CANNOT ACCURATELY SAY WHO SAID WHAT. WHAT I HOPE THIS IS NOT AN EXAMPLE OF IS THE FAA'S POS ON NOT CORRECTING A READBACK WHEN A PLT GIVES THE READBACK INCORRECTLY; AS THIS HAS BEEN A TOPIC OF DISCUSSION LATELY. IF THIS WAS INDEED WHAT HAPPENED; I FEEL THE FAA SHOULD SERIOUSLY RETHINK ITS POS ON CORRECTING CLRNC READBACKS. IT ALSO SHOULD BE NOTED THAT DURING OUR TIME WITH HARRISBURG APCH IT TOOK NUMEROUS XMISSIONS TO ATC TO ADVISE THEM OF WHAT WE WANTED TO DO; AND THEY DID NOT REPLY IN A TIMELY MANNER. WHEN THEY DID REPLY; IT SEEMED AS IF THEY WERE CONFUSED OF WHAT WE WANTED TO DO. THE WX AND EARLY MORNING HRS MAY HAVE CONTRIBUTED TO THIS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR WAS POSITIVE HE HEARD THE CTLR CLR THE ACFT TO 2000 FT. THEY WERE IN HVY CONVECTIVE ACTIVITY AND THE ACFT RADAR WAS ATTENUATING SEVERELY; SO AS TO MAKE IT ALMOST USELESS. THE ONLY WAY TO SEE THE TSTM CELLS WAS TO GET UNDER THEM SO THE LIGHTNING WAS VISIBLE. THIS WAS THE REASON FOR THE REQUEST FOR LOWER ALT. THE RPTR STATES THAT OTHER PLTS HE KNOWS ARE CONFUSED ABOUT THE CTLR RESPONSIBILITY FOR READBACK VERIFICATION. HE STATED ARTICLES IN A PROFESSIONAL PLT PUB FURTHER CONFUSE THE ISSUE. HE SUGGESTED THAT THE FAA ISSUE A POLICY STATEMENT THAT WOULD RETURN POLICY TO THE WAY IT USED TO BE. HE STRESSED THAT 'AREN'T WE SUPPOSED TO BE WORKING TOGETHER.'