YOKOTA AIR BASE, Japan — The UH-1N helicopter involved in May 7’s “controlled” emergency landing at a ski resort near Mount Fuji returned to Yokota on Thursday, base officials said.
Maintenance and safety experts determined that a pneumatic line connected to the aircraft’s fuel-control assembly failed, forcing the four-member aircrew to set the helicopter down. The faulty part was replaced and additional inspections were conducted before it departed from Yamanashi Prefecture.
Meanwhile, the Tokyo Metropolitan Government and the six cities surrounding Yokota submitted a letter Wednesday to base officials, requesting that the four UH-1N helicopters from the 459th Airlift Squadron be grounded for an extended safety review.
“Repeated emergency landings could lead to a major accident and anxiety among the residents are growing greatly,” the letter stated.
Saturday’s incident was the fourth involving a Yokota helicopter since Aug. 19. None has resulted in injury or damage.
The letter, addressed to Col. Mark Schissler, the 374th Airlift Wing commander, asked for even more thorough maintenance and permanent preventive measures to ensure safety. The group also is seeking information about current procedures.
After a UH-1N crew made a precautionary landing Nov. 23 at Tokyo’s Chofu Airfield, when an abnormal transmission light indicator popped up in the cockpit, Schissler ordered a review of Yokota’s maintenance procedures. It took about two days; no lapses were discovered, officials said.
Capt. David Westover, a 374th Airlift Wing spokesman, said Yokota officials received the petition Wednesday and offered a written response to the Japanese authorities.
“We fully understand the concerns of the Japanese citizens and we apologize for any anxiety or inconvenience this incident may have caused,” Westover said. “We appreciate the cooperation from the local city and government officials in helping us resolve the situation.”
First Lt. Warren Comer, a wing spokesman, said there are no plans to ground the UH-1N fleet.
Maintenance and safety personnel conducted a full inspection of the aircraft involved in Saturday’s emergency landing, base officials said. They also checked for the pneumatic-line defect in the other three UH-1N helicopters at Yokota and found those aircraft to be functioning properly, officials said.
About 5:30 p.m. May 7, the four-person crew aboard the UH-1N helicopter noticed engine trouble in one of the aircraft’s two engines. Pilots guided it down onto a parking lot of the Fuji Ten Snow Resort in Narusawa-mura, Yamanashi Prefecture, without losing control, Air Force officials have said.
Since its inception in 1993, the 459th Airlift Squadron has not had a major accident. The unit won the Pacific Air Forces Flight Safety Award the past two years.
Yokota’s UH-1Ns have flown more than 10,000 transport and training missions since 1997, totaling almost 10,000 flying hours.
