Narrative:

Established on final approach for an ILS transition to visual approach at runway 9R, miami airport. We were being vectored behind a foreign carrier (B707) 'heavy.' the winds were calm and we had approximately 6 mi spacing. The 707 maintained approximately 2000 ft altitude and conducted extensive communications with the controller as he was having difficulty acquiring the airport, although the WX was clear. The 707 eventually acquired the runway and accomplished a relatively short, steep approach. As we approached the glide path, we encountered a sudden roll to approximately 30 degree left bank. I disengaged the automatic pilot to recover. The aircraft responded normally as the autoplt was disengaged. After a second encounter (flying manually) producing only a moderate 'bump,' I flew slightly high on final. We encountered the vortex 2 or 3 more times on final, including a moderate one in transition to landing. Because we were both concentrating on the encounters and our anticipated reactions to any significant disturbance on final, the PNF (captain) evidently did not switch to tower. After landing and clearing the runway, we realized our situation, switched to ground and proceeded without further incident. I do not recall the controller directing a radio change and do not recall hearing a landing clearance. My concentration on flying the approach (and anticipating another vortex encounter of the magnitude of the first one) apparently constituted a distraction I had not previously prepared for. Although we did not experience a situation that specifically broke the stabilized approach principle, the encounter was significant/violent enough to break up our concentration and evidently disrupted our crew coordination. Requesting a 360 degree turn or vectors for additional separation may have allowed additional time for the vortex to clear and may have improved our coordination during the approach and landing.

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Original NASA ASRS Text

Title: ACR MLG LANDED WITHOUT CLRNC. (X)

Narrative: ESTABLISHED ON FINAL APCH FOR AN ILS TRANSITION TO VISUAL APCH AT RWY 9R, MIAMI ARPT. WE WERE BEING VECTORED BEHIND A FOREIGN CARRIER (B707) 'HVY.' THE WINDS WERE CALM AND WE HAD APPROX 6 MI SPACING. THE 707 MAINTAINED APPROX 2000 FT ALT AND CONDUCTED EXTENSIVE COMS WITH THE CTLR AS HE WAS HAVING DIFFICULTY ACQUIRING THE ARPT, ALTHOUGH THE WX WAS CLR. THE 707 EVENTUALLY ACQUIRED THE RWY AND ACCOMPLISHED A RELATIVELY SHORT, STEEP APCH. AS WE APCHED THE GLIDE PATH, WE ENCOUNTERED A SUDDEN ROLL TO APPROX 30 DEG L BANK. I DISENGAGED THE AUTO PLT TO RECOVER. THE ACFT RESPONDED NORMALLY AS THE AUTOPLT WAS DISENGAGED. AFTER A SECOND ENCOUNTER (FLYING MANUALLY) PRODUCING ONLY A MODERATE 'BUMP,' I FLEW SLIGHTLY HIGH ON FINAL. WE ENCOUNTERED THE VORTEX 2 OR 3 MORE TIMES ON FINAL, INCLUDING A MODERATE ONE IN TRANSITION TO LNDG. BECAUSE WE WERE BOTH CONCENTRATING ON THE ENCOUNTERS AND OUR ANTICIPATED REACTIONS TO ANY SIGNIFICANT DISTURBANCE ON FINAL, THE PNF (CAPT) EVIDENTLY DID NOT SWITCH TO TWR. AFTER LNDG AND CLRING THE RWY, WE REALIZED OUR SIT, SWITCHED TO GND AND PROCEEDED WITHOUT FURTHER INCIDENT. I DO NOT RECALL THE CTLR DIRECTING A RADIO CHANGE AND DO NOT RECALL HEARING A LNDG CLRNC. MY CONCENTRATION ON FLYING THE APCH (AND ANTICIPATING ANOTHER VORTEX ENCOUNTER OF THE MAGNITUDE OF THE FIRST ONE) APPARENTLY CONSTITUTED A DISTR I HAD NOT PREVIOUSLY PREPARED FOR. ALTHOUGH WE DID NOT EXPERIENCE A SIT THAT SPECIFICALLY BROKE THE STABILIZED APCH PRINCIPLE, THE ENCOUNTER WAS SIGNIFICANT/VIOLENT ENOUGH TO BREAK UP OUR CONCENTRATION AND EVIDENTLY DISRUPTED OUR CREW COORD. REQUESTING A 360 DEG TURN OR VECTORS FOR ADDITIONAL SEPARATION MAY HAVE ALLOWED ADDITIONAL TIME FOR THE VORTEX TO CLR AND MAY HAVE IMPROVED OUR COORD DURING THE APCH AND LNDG.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.