MLT ALTDEV OVERSHOT DURING GAR AT SJC.

Narrative

ON JAN/XX/92 WE DEPARTED SAN JUAN INTL (PR) ON A LCL AIR REFUELING MISSION. AFTER AN UNEVENTFUL MISSION; WE OBTAINED CLRNC BACK TO SAN JUAN AND STARTED OUR DSCNT. DUE TO POOR WX (LOW CEILING; LOW VISIBILITY; NIGHT; RAIN); AND TFC CONGESTION; WE WERE GIVEN SEVERAL VECTORS AND STEP DOWN ALTS. SINCE WE WERE TOLD BY ATC TO EXPECT THE ILS RWY 8; I 'SET-UP' AND BRIEFED MY CREW ON THE ILS RWY 8 PROCS. AT APPROX 10 MI FROM THE FIELD; WE WERE CLRED 'ILS RWY 10; CIRCLE RWY 8.' AS A RESULT OF THIS SHORT NOTICE CHANGE AND INADEQUATE APCH PLANNING IN POOR WX CONDITIONS; I WENT MISSED APCH. I WAS GIVEN RADAR VECTORS AT 2000 FT TO EVENTUALLY ATTEMPT ANOTHER APCH. THE INITIAL VECTORS WERE N; THEN W; THEN SW ON A 220 HDG. MY CREW INFORMED ME THAT WE WERE HEADED DIRECTLY FOR A 4290 FT MOUNTAIN PEAK AND THE MSA FOR SAN JUAN WAS 5100 FT. WE ATTEMPTED TO CONTACT APCH CTL; BUT WERE UNABLE DUE TO RADIO CONGESTION. OBVIOUSLY APCH CTL FORGOT ABOUT US. AT 5 MI FROM THE MOUNTAIN PEAK; I WAS AFRAID OF HITTING RISING TERRAIN AND DIRECTED MY CREW TO TAKE ACTION. AT THAT TIME; APCH INSTRUCTED US TO CLB IMMEDIATELY TO 4400 FT AND TURN IMMEDIATELY TO A 110 HDG. I TREATED THIS THE SAME AS A GPWS (GND PROX WARNING SYS) 'PULL UP' WARNING. FOR SAFETY REASONS; I APPLIED GAR THRUST AND AGGRESSIVELY APPLIED 20 DEGS PITCH AND 30 DEGS BANK IN ORDER TO AVOID ANY GND IMPACT. THE UPWARD VECTOR RESULTED IN AN ALTDEV. I INADVERTENTLY CLBED TO 5100 FT BEFORE CORRECTING BACK TO 4400 FT ASSIGNED. WE WERE CLRED FOR THE ILS RWY 8. THE APCH/LNDG WAS UNEVENTFUL. FACTORS IN THE MISSED APCH: INADEQUATE APCH PLANNING (ESPECIALLY NIGHT IMC). ATC SHOULD ANTICIPATE THE TYPE APCHS. CIRCLING APCH AT NIGHT IN MARGINAL WX. ATC SHOULD ONLY ISSUE STRAIGHT-IN APCHS. FACTORS IN THE TERRAIN AVOIDANCE/ALTDEV: SAFETY COMES FIRST. I DID WHAT WAS NECESSARY TO SAFELY RECOVER MY AIRPLANE. HUMAN CONSIDERATION -- FEAR OF DYING! TFC CONGESTION/POOR WX CAUSED ATC TO FORGET ABOUT US AND VECTOR US TOWARD A MOUNTAIN AT LOW ALT. APCH CTL SHOULD PLAN THEIR ARRS TO AVOID SATURATION -- USE HOLDING PATTERNS OR GATE HOLDS.