An Atlas Air Boeing 747-400 freighter, registration N473MC performing flight 5Y-4402 from Zhengzhou (China) to Anchorage,AK (USA), was climbing out of Zhengzhou when the crew stopped the climb at 5700 meters (FL187) due to the loss of the #1 hydraulic system. The crew decided to divert to Seoul (South Korea) maintaining around 390 knots over ground (290 KIAS). On approach to Seoul, now maintaining FL170, the crew advised they had all gear down and locked, however, would not have nose gear steering, they'd stop on the runway and needed to be towed off the runway, and they needed to dump fuel. As a precaution the crew requested emergency services on stand by for the arrival. The aircraft continued for a safe landing on runway 33R about 2:40 hours after departure.
The aircraft is still on the ground in Seoul about 17 hours after landing.