With many airlines in the U.S. and worldwide grounding the Boeing 737 MAX for an indeterminate time in 2019 due to safety concerns, hundreds of the planes remain in long-term storage until commercial airlines clear them to resume flying.

The family of 737 aircraft ranges in price from $89 million for the 737-700 to $135 million for the 737 MAX 10, according to The Boeing Company, so proper storage of the pricey plane is essential. But how do you store a 737, an aircraft roughly 116 feet long that has a 117 feet wingspan?

Storage and maintenance needs for the 737 differ when it comes to short-term or long-term storage, says Tim Zemanovic, former owner of an airplane storage facility and president of Fillmore Aviation, an aircraft disassembly firm in Farmington, MN.

The Boeing 737 maintenance manual classifies short-term storage as periods from 0 to 60 day and long-term storage as a time longer than 60 days.

Boeing has an extensive list of maintenance and storage instructions for storing a 737 long-term, but here are some of the basics that must be followed to prevent damage to the plane.

Store Outside

The 737 is typically stored outside day and night due to hangar space constraints, says Zemanovic.

Climate is Crucial

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A desert climate is ideal for 737 storage, since little to no moisture or humidity helps keep mold, mildew and corrosion away, says Zemanovic. If stored in a winter climate, the Boeing maintenance manual recommends putting sand or a coarse fiber mat between the tires and ground during a hard freeze to prevent tires from freezing to the ground.

Protect External Surfaces

At the beginning of long-term storage, several steps must be taken to protect the plane’s exterior, according to the Boeing maintenance manual:

  • Seal fuselage openings, all external doors and hatches and the upper half of the nose radome, which encloses the plane’s radar set and antenna, with yellow vinyl adhesive tape, to prevent water entering
  • Make sure all drain holes are open
  • Put a screen over all drain holes
  • Apply a protective coating to unpainted metal surfaces
  • Apply a corrosion-inhibiting compound to radome latches, the plane’s electronic antennae and radar enclosure

Add Fuel Additive

A one-time fuel additive keeps fuel from going bad and prevents sealant deterioration in the fuel tanks.

Remove Batteries

Remove flashlight and other non-rechargeable batteries and install new batteries when the plane is put back in service.

Vent Planes

In a high-heat desert climate, supply ventilation to the 737 by opening cabinets, closets and interior doors frequently, for up to the entire day, to avoid damage to seats and other furnishings. Vacuum often and cover seats to protect from dust.

Prevent Indoor Moisture

The Boeing maintenance manual instructs technicians to place desiccant bags (similar to silica packets  used in packaging to absorb moisture) inside the plane to prevent mold and mildew.

Preserve Landing Gear and Flight Controls

For long-term storage, the landing gear and flight controls must be lubricated, operated and checked for corrosion regularly, according to the Boeing manual. Turn tires at least one-third of a turn every month to prevent deflation. Apply hydraulic fluid to exposes actuator rods and valve slides.

Featured photo originally posted to Flickr by lynothehammer1978 at https://flickr.com/photos/71965027@N02/43406207022. It was reviewed on  by FlickreviewR 2 and was confirmed to be licensed under the terms of the cc-by-2.0.