Narrative:

We were cleared for the ILS runway 05 at cyyz. We broke out just inside the outer marker and had the approach lights and runway in sight. There was rain over the north half of runway 05 extending to the west. As we got over the approach lights and I began to reduce power to slow and begin the transition; we hit heavy rain and our forward visibility was greatly reduced. We were able to land but the rain intensified to where we could not see out the forward windows. We struggled to find the runway exit (H3) and were able to exit; but then continued slightly right onto an access road. We soon realized our mistake; notified ATC and were cleared for a 180 degree turn and hold short of runway 05. Just as I was turning back onto the taxiway; I noticed what appeared to be a light that had the glass top knocked off. I was not sure if this was done by us or not; but we mentioned this to toronto ATC and they sent a crash fire rescue equipment truck out to check. We never heard of the findings of their investigation whether it was us or not. We thought it was possibly done by us as we had our flaps in the 'ground' position as we taxied off. We checked out our aircraft thoroughly once we cleared customs. I gave my name and phone number to crash fire rescue equipment and secured the a/c for the evening. The next morning we inspected the aircraft again more thoroughly and again found no evidence of any impact with a light.

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Original NASA ASRS Text

Title: CE525 Captain reports landing in a rain storm reducing forward visibility to near zero. Once off the runway on the desired taxiway an inadvertent turn onto a service road is made; requiring 180 turn back to the taxiway. No damage to the aircraft is reported.

Narrative: We were cleared for the ILS Runway 05 at CYYZ. We broke out just inside the outer marker and had the approach lights and runway in sight. There was rain over the north half of Runway 05 extending to the west. As we got over the approach lights and I began to reduce power to slow and begin the transition; we hit heavy rain and our forward visibility was greatly reduced. We were able to land but the rain intensified to where we could not see out the forward windows. We struggled to find the runway exit (H3) and were able to exit; but then continued slightly right onto an access road. We soon realized our mistake; notified ATC and were cleared for a 180 degree turn and hold short of Runway 05. Just as I was turning back onto the taxiway; I noticed what appeared to be a light that had the glass top knocked off. I was not sure if this was done by us or not; but we mentioned this to Toronto ATC and they sent a CFR truck out to check. We never heard of the findings of their investigation whether it was us or not. We thought it was possibly done by us as we had our flaps in the 'ground' position as we taxied off. We checked out our aircraft thoroughly once we cleared customs. I gave my name and phone number to CFR and secured the a/c for the evening. The next morning we inspected the aircraft again more thoroughly and again found no evidence of any impact with a light.

Data retrieved from NASA's ASRS site as of July 2013 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.