Parking Or Storing An Airplane? Read This

With the COVID-19 pandemic showing no signs of a quick easing, business aircraft could be parked for several months or even longer. Owners and operators need to understand that when an airplane is to be grounded for such extended periods, they can't simply tow it into a hangar and cover the engines and pitot tubes.

“The modern business jet doesn’t like to sit around,” Thoroughbred Aviation president Nathan Winkle said during an April 9 National Business Aviation Association webinar on maintaining parked aircraft. “We’re going to have some issues [if it does]."

Those issues will be compounded and become more costly and time-consuming if operators and owners don’t ready their airplanes for a period of inactivity—and perform maintenance before and during that period, Winkle and other maintenance experts said on the webinar and in interviews with BJT.

First, it's important to determine whether the aircraft will be parked for a short while or stored for an extended period, Kasey Harwick, Duncan Aviation vice president of aircraft services in Lincoln, Nebraska, told BJT. Short-term parking requires different maintenance measures than does long-term storage, which calls for specific preservation actions to the airframe and engines that are generally outlined by airframe and engine manufacturers in their maintenance manuals.

For short-term parking, Harwick recommends putting the aircraft in a hangar. If a hangar isn’t available, parking the airplane on a level surface and into prevailing winds as well as mooring it—especially for instances of severe weather—is the next best option, he said. Also, install safety equipment such as landing gear lock pins, chock the landing gear, and ensure that all access doors and panels are secure. Static and protective covers for engine inlets and exhaust should be installed as well as on pitot probes. Operators should also attach an aircraft grounding cable, set all master switches and controls in the flight compartment to off or neutral, and center control surfaces and use gust locks if available. Harwick added that the airplane’s batteries should be disconnected, and tires should be maintained at the manufacturer’s specified pressures.

Harwick and others also suggested “exercising” the airplane every week or two that it is idle. That means pulling it out of the hangar and onto the ramp and running every system as well as taxiing it, which gets fluids running through the aircraft and the wheels moving to avoid the formation of flat spots on the tires. (Those can also be avoided by regularly rotating the tires.) In addition, it's advisable to run the airplane’s lavatory and environmental-control systems as well as its satcom and wireless internet, in case software updates need to be downloaded. “Just like us human beings, an airplane needs to get out, stretch, and get some exercise,” Western Aircraft director of aircraft services Jody Harris told BJT.

For aircraft that are stored long term, experts recommend following manufacturer guidance on the airframe, engines, and APU, since each aircraft model is unique. But along with that, Harwick suggested routinely draining water from the fuel tanks and performing a fuel-contamination test, if possible. He also noted that some engines require placement of desiccant on a rack in the inlet and exhaust of the engine, followed by placing a humidity indicator card in them to ensure excessive moisture isn’t accumulating, and masking the inlet and exhaust off with plastic. Lastly, it’s important to continue to conduct regularly scheduled inspections while the aircraft remains in storage, Harwick added.

One area that can be overlooked when parking or storing an aircraft is the preservation of its exterior and interior, according to Immaculate Flight director of operations Phillip Hoyme. Hoyme, whose company specializes in aircraft cleaning, said that a professional should clean and apply protection to the aircraft’s exterior and interior before you park or store it. This will help ensure that the paint remains undamaged and prevent mold and mildew from developing in the cabin.

“You would much rather protect than restore on the back end,” he said. Hoyme added that keeping an aircraft parked or stored in a cool environment is optimal for its preservation and return to service. As such, it's a good idea to place a sunscreen in the cockpit and lower the window shades in the cabin.

Desiccant can be used inside the airplane to prevent any moisture build-up as long as the bags are changed once full. Moreover, Hoyme said, it’s wise to regularly air out the cabin by opening all access points, including the baggage compartment. “You want to make sure you’re getting air moving through as much as possible,” he said.

Perhaps just as important is documenting everything that you do to the airplane while it is parked or stored, Winkle suggested during the webinar. Doing so could avoid a lot of hassles later on, when you decide to sell the aircraft, “because [the steps you take] could have an impact on value.”