Mechanics and repairers,
Your ability to prevent damage to aircraft systems in varying Alaska cold-weather conditions has an impact on your UH-60 aircraft being able to operate when needed.
Cold weather is a threat to you, your crew and everyone who maintains the aircraft. Even when moving an aircraft into the hangar from the arctic cold for maintenance, there are second- and third- order effects to consider. To help survive arctic weather, follow these techniques suggested by CW4 Joshua Meyers (who spent six years as an MTP in Alaska) to reduce maintenance time on UH-60 aircraft.
• Practice P4T3. Problem - Plan - People - Parts - Tools - Time - Training. Following this process makes your maintenance easier, smoother and shorter over time.
• Always cover grounding points with orange traffic cones on the parking ramp. This makes refueling easier and assists with marking parking spaces when the ramp is covered in snow and ice. It may also be a good idea to attach heavy used truck tires to the cones to make sure they remain in place and don’t blow away during aircraft operations and ground taxiing.
• Don’t fully open the hangar doors if it’s not necessary. Opening the doors fully makes re-heating the hangar take longer, which delays maintenance. That means you stay at work longer.
• Don’t leave fuel selector levers in direct or cross-feed positions; fuel selector levers will always be left in the OFF position when outside. This is a serious safety issue and a Red X condition. If the cable freezes with the lever in DIR or XFD, emergency engine shutdown and fuel removal can’t be done during a fire or engine failure to the high side. It’s important to include this info in your unit’s standard operating procedures (SOP).
• Always check that engine inlets don’t have water in them prior to opening hangar doors and pushing an aircraft out. This prevents ice in engine inlets found during pre-flight.
• When an aircraft needs to thaw in the hangar in a short amount of time, open all aircraft doors and cowlings to allow air to better circulate through the aircraft. This speeds up the time it takes to thaw.
• When a strut requires servicing, DO NOT service for dimension X. If you have to service any strut for inadequate extension, completely de-service (both hydraulic and nitrogen) the strut, and completely re-service. Then, later in the winter, you won’t continually delay or cancel flights and waste time repeatedly re-servicing a bad strut that should have been replaced earlier. It’s important to include this info in your unit’s standard operating procedures (SOP).
• Always Red X the aircraft when the hydraulic quick disconnects (QDs) have been disconnected. Whenever aircraft will be parked outside with sustained temperatures below -20°F, disconnect all six (6) hydraulic QDs. This prevents the reservoir from emptying when hydraulic seals shrink from extreme low temperatures.
• Don’t turn the main rotor system with the QDs disconnected. If you do then you have just pressurized the #1 and #2 hydraulic pumps. This makes re-connecting the QDs extremely difficult until the pressure bleeds off.
• Service all 4 main rotor dampers to full during corrosion control inspection (CCI), 40-hour and 120-hour inspections. This prevents, on average, 3 to 5 flights a month from being delayed and subsequently servicing them in the cold.
• If servicing spar pressure on any main rotor blade on a UH-60 A or L Black Hawk, service all the remaining blades at the same time. It’s also recommended in the IETM. This helps prevent red blade indication method (BIMs®) at a later date. The BIM is a part installed at the root of the main rotor blade that indicates or confirms structural integrity of the blade. It’s checked during all phases of maintenance and on pre-flight.
• Plan to have the next day’s flight schedule aircraft and spare in the hangar if possible. Also plan how the aircraft are arranged so that moving them out can be a smooth process, minimizing the amount of time the hangar door remains open.
• Always plan tail rotor cable tension and blade spar pressure checks for 0630 if possible. Have the aircraft in the hangar the night before so that the aircraft will be stabilized at normal temperatures. Coordinate for maintainers to be available at 0630 to complete the task (P4T3).
• When snow falls, have a plan in place for rotating aircraft that were left outside back into the hangar. That allows snow and ice to melt off. It’s best to begin with the fully mission capable (FMC) aircraft first followed by the maintenance aircraft.
• When snow falls, have a parking plan in place to facilitate the ramp to be plowed. Use whatever works best for your unit’s parking situation on your installation.