runway excursion on landingA Saudi Arabian Airlines Boeing 747-300, registration HZ-AIS performing flight SV-817 from Riyadh to Madinah (Saudi Arabia) with 265 passengers, veered right off Madinah's runway 17 when the #1 thrust reverser (outboard left) did not open while landing in Madinah at around 20:15L (17:15Z). The airplane came to a stop with all gear off the paved surface about 100 meters off the runway and about 3 meters off taxiway B. No injuries occurred, the airplane received damage to the left hand flaps and engine #1 cowling (outboard left hand) that contacted the ground as result of the runway excursion and wheels sinking into soft ground. The passengers disembarked via mobile stairs.