Air New Zealand engineers have begun putting the airline's Boeing 777s into a "deep sleep" among tens of billions of dollars worth of other aircraft in United States deserts.
The airline will park 12 of the aircraft at Roswell in New Mexico and at Victorville in California, where three of the planes are already in storage.
Because of the pandemic the airline doesn't expect them to be flying until September next year at the earliest.
Group general manager engineering and maintenance Brett Daley said the desert facilities with low humidity and plenty of space were ideal for storing aircraft.
Victorville is about a 45-minute flight from Los Angeles. The ex-US Air Force base is in the Mojave Desert where the main hazards are dust and insects.
When the aircraft arrive a team of LA- based Air NZ engineers settle them in with staff from the Victorville base, known as the Southern California Logistics Airport.
Daley said it could take several days to park planes because they have to be towed into position around other expensive aircraft. The process of parking and sealing them up takes a week.
All doors and undercarriage doors are closed. Any opening and the pitot static monitoring equipment - small tubes attached to the fuselage - are sealed.
The engines have dense fabric coverings to keep dust and insects out. The undercarriage is also covered to protect tyres from dust and the odd rainfall event.
"The majority of the activity is around making sure you don't get the ingress of dust or you don't get contamination of any of the componentry and engines," Daley said.
The planes have been in "active storage" at Auckland and Christchurch since March and were flight-ready with systems regularly powered up.
In the desert they were dormant.
"You don't bring them back to life by activating systems or putting power through them — they are in a state of deep sleep."
Victorville staff monitor the planes but Air NZ's engineers will inspect surfaces once a week and will do more detailed inspections once a month, including looking inside the planes to make sure no dust had got into them.
Nothing, including batteries, was stripped from the planes during storage which was done according to a Boeing checklist and with input from technicians who have gained experience in the unprecedented rush to park up planes this year in what is the worst financial crisis in aviation history.
"We really want to make sure that aircraft are in a condition so that if we were to need them before September, 2021, we would be in a position to bring them back into service within six week to two month time frame."
Early in the pandemic it was estimated that 16,000 planes were grounded as global capacity fell to around 31 per cent of last year. Although it has clawed its way back to around 50 per cent, there are still thousands of planes lying idle.
The Air New Zealand planes are near eight of the Qantas A380 fleet which is grounded for at least three years. Aircraft from other leading global airlines are nearby.
Because of their negotiating power airlines do not pay full price for planes but if bought new 777s have a list price of just on $500 million. An A380 costs close to $670m.
In its full year results Air New Zealand booked a $338m aircraft impairment charge.
The airline would not disclose the cost of parking planes in the desert but one report earlier this year put the cost of putting a much smaller Boeing 737 in storage at around $3000.
''It's expensive in terms of lost revenue and expensive because the significant amount of ongoing maintenance,'' said Daley.
''It is a very difficult situation. Aircraft aren't designed to be parked. It's unfortunate that Covid has put us in this situation. Our hope from an engineering and maintenance perspective is that we see these aircraft flying as soon as practicable.''
The airline is keeping three 777s in New Zealand to meet any increased demand but its 14 Boeing 787s will do its international flying, now dominated by freight journeys.
Daley didn't believe Air NZ had stored any of its planes in active service in the desert before but had retired older aircraft to ''boneyards'' before.
The airlines 777-300s have an average age of eight years and its 777-200s which joined the fleet in 2005 have an average age of nearly 14 years.