Having an aircraft land on the flight deck of the aircraft carrier USS Nimitz (CVN 68) is an extremely dangerous feat. Seeing the aircraft ripping through the skies, then suddenly touch down and come to an almost immediate halt is a process that few ever get to see in person. Capturing a landing aircraft involves numerous flight deck personnel utilizing four cables, called cross deck pendants, and an aircraft’s tail-hook to stop the aircraft landing on the deck at full speed.
Calculating the exact pressure needed to stop every different type of aircraft landing is a science and could mean the difference between life and death. The cross deck pendants catching the planes can’t do their job without the five arresting gear engines designed to take the force of each landing aircraft, making them a necessity for ship operations.
Air Department’s V-2 division, is currently in the process of taking apart arresting gear engine five and performing maintenance to prepare Nimitz for sea.
“This is corrective maintenance because it was leaking,” said Aviation Boatswain’s Mate (Equipment) 1st Class Robert Reed, the leading petty officer of V-2’s arresting gear division. “It’s important because if it is leaking it won’t do its job, which is catching the plane properly.”
The arresting gear engines on board Nimitz are hydraulic systems that need packing at the end in order to keep fluid from leaking out. In order to effectively stop an aircraft landing on the flight deck, that packing has to occasionally be replaced.
Engine five has an important role as the barricade engine. The barricade is what Nimitz uses to catch aircraft in an emergency landing. It doesn’t get operated as often as the other engines, inspected as often, or used in actual landings, but it plays a vital role on board.
“Its like an emergency airbag,” said Aviation Boatswain’s Mate (Equipment) 3rd Class Michael Toone. “So the packing on it doesn’t get replaced as often as the other ones, but you need to be able to catch an aircraft in an emergency. It has to work perfectly.”
The maintenance associated with the equipment is difficult and has brought on unforeseen challenges.
“The biggest challenge we’ve had so far was that we couldn’t get the ram out of the main engine cylinder (MEC), so we had to utilize shop 740,” said Reed, referring to civilian workers from Puget Sound Naval Shipyard and Intermediate Maintenance Facility, where Nimitz is currently undergoing an extended incremental availability.
The ram, which is similar to a giant piston, acts as a syringe pushing fluid through the MEC.
“Shop 740 brought their equipment and helped us jack the ram out of the MEC. They were a big help to us,” said Reed.
Even without complications, maintenance can prove to be difficult due to sheer size alone.
“It’s probably the biggest, heaviest equipment we have installed on our systems,” said Toone. “You’re looking at around 16,000 pounds of equipment that you have to move more than 20 feet to access. It’s big and heavy, and replacing the packing itself around a 20-inch diameter piston is actually a pretty delicate process. If you damage, bend, or warp it in anyway, it’s no good and you have to get new packing.”
The challenges faced give junior and senior Sailors alike an opportunity to learn more about their equipment and think on their feet in order to overcome obstacles.
“This maintenance requires all sorts of technical expertise and knowledge on how the system operates,” said Toone. “Actually being able to get in there and take it apart is a great learning tool to teach them how the whole system works. This gives them hands on training.”
The maintenance has no real timeline, as it could change at any time depending on what complications are faced. However, with every new complication there is another chance for Sailors to learn. Reed said it could take a couple days to a couple weeks to complete, depending on whether or not things run smoothly.
Launch and recovery is essential to the success of the mission. Having aircraft catapult off of the flight deck only to come touching down later on is like a well constructed symphony with V-2 division working constantly to tune all the equipment. V-2 continues to tirelessly complete mission critical maintenance in order to get Nimitz back to sea.
Story and photos by MC3 William Blees