Problems can exist years
before fixes implemented
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©1999 Dayton Daily News
The fire burned out of control inside the CH-46 Sea Knight helicopter as Capt. Jack Estepp spotted the coastline seven miles away through the clear Hawaiian night.
"We started smelling something," he said. "Then the fire started. I didn't want to see anybody get hurt. These guys are my friends."
What Estepp smelled on that October night in 1996 was leaking hydraulic fluid, a smell that had become familiar to many of the crews flying CH-46s
The Hawaii crash is one of at least 71 incidents spanning more than 11 years involving hydraulic problems in Sea Knight helicopters, the Navy and Marine Corps' medium-lift troop and cargo transport, capable of carrying up to 28 soldiers and passengers.
None of the incidents was fatal, but in several cases, like the one in Hawaii, crews barely escaped with their lives. At least three helicopters were destroyed.
And the problems continue.
On March 9 of this year, 11 years after the first hydraulic problem was reported, a Sea Knight made an emergency landing near Malibu Bluff Community Park, 200 feet above the coast and in the center of the city of Malibu, Calif.
Three days later, a Sea Knight carrying reporters and photographers off the USS Bonhomme Richard in California caught fire when an hydraulic line broke. Two people, one a TV anchor, were treated for smoke inhalation.
An 18-month Dayton Daily News examination found that the military's handling of the hydraulic failures on Sea Knight helicopters is typical of the way it handled numerous other mechanical failures in many types of aircraft: Problems dragged on until they became catastrophic.
"We have to make hard choices based on dollars and cents," said Marine Corps Col. Roger Dougherty, a former Sea Knight pilot and until June the director of aviation safety at the Naval Safety Center in Norfolk, Va. "If it's a high risk that's going to happen often, it gets fixed. That's the bottom line."
The Daily News examination found that problems such as those involving the Sea Knight hydraulic system often continue for months, years, even decades. Sometimes costly solutions aren't implemented until aircraft start falling from the sky or the death toll rises.
"The point is the system reacts, albeit slowly sometimes, to the requirements that we generate here," said Bill Mooberry, executive director of the Naval Safety Center in Norfolk, Va. "It doesn't react slowly simply because it's unresponsive. It's simply that the facts are that the process takes time and money and engineering and analysis and all that other stuff to get it fixed."
Unlike the Federal Aviation Administration, which monitors civilian aviation safety, the Naval Safety Center cannot mandate safety changes. It cannot issue fines. It cannot ground aircraft. It cannot force the service to install a safer part on an aircraft.
"The Navy makes the decisions," Mooberry said. "All we do is advise. I don't have the power here to enforce. . . . I have the power of moral persuasion.
"I can whine and pound on the desk and jump on people's tables and beat at the rugs and stuff like that to try to get their attention, but as far as the decisions about who does what to whom. . ., safety is part of it, but it's not the only part.
"I don't direct anything. Nobody here directs anything."
The Sea Knights have three hydraulic systems: Two operate critical flight controls, and one of those is a backup. The third system is the utility hydraulic system, operating the rescue hoist, the huge rear cargo ramp, an engine exhaust device and the cargo winch.
Nearly all of the hydraulic failures, identified in a database from the Naval Safety Center, involved the utility hydraulic system. The safety center did not consider the utility system to be "flight critical," a formal term used by safety officials when determining risks.
The hydraulic failures started in 1988, about the time the Navy upgraded its fleet of Sea Knights with new, more powerful utility hydraulic pumps.
"The problem with that (new) pump was it was just too strong," said Marine Corps Maj. Tim Clubb, who oversees parts acquisition for the CH 46.
The new pumps increased the pressure in the hydraulic system by 15 percent, and, at the same time, increased the amount of fluid flowing through the system. The increased pressure in the lines, Marine Corps officials acknowledged, could increase the risk that leaking fluid could become atomized, or flammable, but they called the 15 percent additional pressure "negligible."
There was another major difference in the pumps. The shaft in the old pumps had an added safety feature: a weak point designed to break when fluid in the system leaked out, through battle damage or mechanical failure.
The new pumps were designed to withstand combat damage, so the shaft had no weak point. It would continue to run without fluid until it burned up and, possibly, caused the leaking fluid to ignite.
From 1988 through 1992, there were at least four utility hydraulic failures on Sea Knights. During the two years that followed, at least a dozen more CH-46 helicopters suffered hydraulic failures. None caused substantial damage.
Until the night of Feb. 18, 1994.
On that night, a Sea Knight carrying a crew wearing night-vision goggles flew from the deck of the USS Inchon. The helicopter had just arrived on the ship, replacing another Sea Knight that crashed the previous month because of unrelated engine problems, killing three people.
Sometime after it left the deck, a crew member reported smoke and a large amount of leaking hydraulic fluid. The Inchon prepared for an emergency landing on deck, but the helicopter crashed into the water, rolled right and then left before floating upside down.
All four crew members were rescued near the spot where the helicopter crash landed.
"This had been a problem that was identified before the Class A (major accident), but sometimes it isn't always apparent of just what the severity of the problem is," Col. Dougherty said. "You have a pump that fails and causes some minor damage and everybody recognizes that we got to get the pump fixed."
Eleven more utility hydraulic failures followed the Inchon crash in 1994, none causing serious damage.
"It took them (Navy safety officials) awhile through trend analysis" to identify the problem, Maj. Clubb said. "We identified it, and we tried to find solutions to solve it."
At one time, the Navy had hoped that all the aging Sea Knights would be replaced by 1994 with the new tilt-rotor V-22 Osprey. But the Osprey program, which dragged as Congress debated cost and other issues, was canceled in 1989, forcing the military to change the way it would view long-term maintenance for the aging Sea Knights.
Then in 1994, Congress brought back the Osprey program, again forcing the military to change its long-term plans for maintaining the aging Sea Knight helicopters.
In 1995, while the Navy still was two years away from approving funding for the new pumps, 10 more utility hydraulic failures were reported. Then, in 1996, helicopters started crashing.
On March 19, 1996, captains Nobert J. Torres and Leo A. Kilgore and 10 others had just taken off from the Marine Corps Air Station in Yuma, Ariz., when the problems started.
"At this point, a lot of black-brown smoke began rushing into the cockpit," Kilgore told accident investigators. "I looked back and saw nothing but orange-red fire and black-brown smoke.
"There was popping and cracking and small muffled booms -- explosions occurring . . . Capt. Torres and I began choking on the smoke."
Filled with smoke and flames, the helicopter landed on the runway, giving the crew just seconds to escape before the flames engulfed the aircraft. Two crew members suffered minor injuries.
"The door (escape hatch) fell to the ground," Torres said. ". . .I jumped from the aircraft."
The Yuma accident was the second hydraulic failure in 12 days, the 29th since 1988.
The following month, on April 19, 1996, the hydraulic pump on a CH 46D from the USS Mars failed, prompting a Navy official to write:
"This is the fourth HAZREP (Hazard Report) our command has released this fiscal year concerning failure of utility hydraulic pumps. Research into history of failing pumps reveals no common deficiency."
Nine more failures were reported in the next five months. In one of those, on Sept. 6, 1996, a helicopter filled with smoke and fumes and was forced to make an emergency landing in a field near Orlando, Fla.
That helicopter was part of President Clinton's entourage traveling in Florida, although Clinton was not on the aircraft.
The following month, Estepp ditched his helicopter into the ocean just off the coast of Hawaii, bringing to at least three the number of Sea Knights lost because of hydraulic problems.
In January 1997, after at least 43 utility hydraulic failures on Sea Knights in nine years, the Navy approved funding for a new pump. But it wasn't until two years later, in January 1999, that the first pump was installed.
The Marine Corps purchased 310 new pumps for the helicopters and this year began installing them at a rate of 40 per month. The pumps and spares cost $5.52 million.
In the meantime, 16 hydraulic failures were reported in 1997, and during the first seven months of 1998, the latest computer data available, there were 13 more incidents.
There were at least two other incidents involving hydraulic failures on Sea Knights this year, both in California.
"We could hear it coming," Paul Adams, recreation supervisor for Malibu Bluff Community Park, said of the March 9 emergency landing near downtown Malibu. "They made a quick but nice landing."
Just four days later, a Sea Knight helicopter from the USS Bonhomme Richard caught fire shortly after takeoff, sending a fireball toward the area where reporters and photographers were sitting.
"It (the helicopter) went up 10 feet, and they noticed the fire so they set it back down," Navy spokesman Tim Jones said.
Dan Green, anchor for KSBW-TV of Salinas, Calif., said the fire started above the huge rear cargo door. That is the area where the hydraulic pump is located.
"I started yelling fire, but nobody could hear me," said Green, who has been piloting single-engine airplanes since 1989. "Everybody had head phones on, and it was very, very loud (inside the helicopter)."
Green and the others watched the fireball move toward them as the helicopter made an emergency landing back on the deck of the ship. The passengers had to exit through the cargo door, just under what appeared to be the source of the fire.
"Towards the end, as we were walking out, we had to stoop very low because of the flames," said Green, one of two people treated for smoke inhalation. "A lot of guys were coughing, and they wanted to get them off the deck.
"Somebody told me -- and this was third hand -- that there was an hydraulic line that leaked and was ignited by a spark."
The Naval Safety Center in Norfolk, Va., identified the cause as a problem in one of the helicopter's hydraulic lines.
By the end of this year, all Sea Knights are expected to have new hydraulic pumps. The V-22 Osprey is not scheduled to completely replace the CH-46 until 2012.
"By the time we completely replace it..., the CH-46 will have served 47 years," Gen. Charles C. Krulak, commandant of the Marine Corps, told the Senate Armed Services Committee in January. "In terms of longevity, that is virtually the equivalent of taking the Wright Brothers' aircraft, flown at Kitty Hawk in 1903, into aerial combat into the Korean conflict in 1950."
Sidebar to Part 6
ANATOMY OF A CRASH - PART SIX
Family, friends grieve, search for answers
'I got the feeling they were withholding something,' pilot's mother says