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Ural Airlines flight 1383 had to land in a field due to hydraulic problems and fuel shortage. The airline does not scrap it, but is repairing (source) and is going to fly it. A320 landing gear is not suitable for soft surface. How are they going to make it run and take off?

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    $\begingroup$ "The airline does not dismantle it, but repairs and is going to fly it." - what's your source for that? The article you linked says that "given the location of the aircraft it is likely to be dismantled in place". $\endgroup$
    – Bergi
    Sep 25 at 19:29
  • $\begingroup$ @Bergi: added source link in the post. $\endgroup$
    – culebrón
    Sep 26 at 5:34
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    $\begingroup$ It also helps that they are presumably going to run at minimum weight / fuel. $\endgroup$
    – TLW
    Sep 26 at 5:47

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TLDR: cold winter will freeze the ground and make it hard enough.

First, there was a similar case of Alrosa flight 514 that landed on a disused runway in Izhma in September 2010, was fixed and flew to the closest airport in January 2011. So fixing a plane out of airport is nothing special.

The difference is that in Izhma that was a disused airport, and a local ex-employee had been cutting newly growing trees on the runway (summary), whereas Ural's A320 is sitting in a completely unpaved field.

But I'm from Novosibirsk and lived there for 30+ years, so I know how things work in that climate pretty well.

1. The ground freezes deep

By late January, the ground becomes frozen 1-2 m deep. That's why pipelines like sewer must be buried 2m deep in the region. Frozen ground is so hard that you can't dig it with a normal spade. To give a perspective: according to material stiffness tables, pure ice at -20°C is harder than pavement brick.

So, if the ground is even enough, there's no problem supporting one plane for one take-off run.

How do you make even ground?

2. There are winter ice roads in this climate

Winter ice road is built for winter months after temperatures become permanently below 0°C. You pour water to melt snow and the ground, even the surface, e.g. with a buldozer, let it freeze deep, and the road is ready. Climate in Novosibirsk isn't particularly cold -- there are much colder places in Siberia -- but every winter there's an ice road made over the water reservoir here.

climate chart from Wikipedia

Tempreratures near Novosibirsk are (almost) permanently below 0 from mid November till mid March. In January, weather is ideal: by this time, there's half a meter of snow on the field, enough to even the ground; anti-cyclones keep skies clear and temperatures low, around -20°C (which actually gives engines a boost in thrust).

Watering the field will actually make it freeze deeper, because ice is a good heat conductor, whilst snow is an insulator.

3. Isn't it dangerously slippery?

No, smooth slippery ice is actually very hard to make. People in warm climate think anything at < 0°C is slippery, but it's not. When I was 10-12 yo, I tried making a slide on a slope and failed utterly: I took a bucket of water and poured it on the ground, and the resulting surface was very bumpy like a sponge, you could almost walk uphill on it. Instead, to make a good icy slide, you need to smooth the surface beforehand and then carefully spray water, not letting it melt through.

Remark: cities in warm climate near the seas regularly have ice rain phoenomenon, when the air above the ground is below 0, but clouds masses are warmer and it rains rather than snows. I've never seen this in the middle of continent.

Only twice in my whole life there was a case when it rained in November same day as temperatures would drop below 0 permanently. Lots of stuff got covered with ice for months, and lots of sidewalks and paths in forests were like ice rink -- the first time, I was a schoolkid and we loved it! (BTW, salt won't help if there's lot of snow and temperatures far below 0.)

By the way, this ice wasn't forever, because it got gradually covered with snow. And normal snow isn't slippery at all, at least if it's colder than 0.

Icy surfaces in Siberia are very likely not in autumn, but in spring, when snow melts on the surface during the day and freezes at night.

So, ice isn't a concern at all. Plus, I believe they landed in this very long field (which seems to have no high-voltage line), so there's plenty of space for a stop in case of aborted take-off.

4. Won't it Damage the Field?

The field gets plowed every year, so bulldozing won't harm anything. Watering it will only do good, because the primary concern in this climate is to have enough moisture in the ground in spring. Dry winter with little snow is very damaging for agriculture.

So, How's the Plane Going to Fly Out?

The recipe, that I believe, Ural Airlines will follow, is this:

  1. Put the plane on hard surfaces, like wood or metal sheets.
  2. Even the necessary field.
  3. Water it regularly.
  4. Let the snow stay couple of weeks before the take-off, to make smooth and non-slippery surface. Compact it with heavy vehicles.
  5. Wait a day with clear sky, and fly the plane, like Alrosa did.

ADDED: replying to @U_flow's comment regarding costs and labor.

First, I don't know if the surface has big waves that may make the aircraft jump before flying. From the photos it looks smooth, and they may need only to run a tractor to finely grind the dirt. But if the landscape is bumpy, they'll need a scraper. (Elevation map shows there are bumps, but smaller than 5 m.)

Here's an aerial photo: enter image description here the aircraft under inpection, photo by Ural Airlines

Second, ice roads are made anew every year, without much noise -- which probably means they cost a tiny fraction of a normal road. The real question is where you get water for the trucks, when they're not on a lake, but in a field. They might need to run trucks to the Ubinskoye town in 10 km. (A temporary pipeline seems problematic, because if water stays still, it freezes and ruptures pipes -- so operations must be very cautious.) Or they can bore a new well -- ground water in that region is high -- although, the place itself is on 10m higher ground.

Route to Ubinskoye, OpenCycleMap

But once the dirt is frozen and sustains a truck, the rest must be easy. Snowfalls are frequent but drop just ~5cm of snow every couple of days, so a truck can work just couple of times a week. Here's an example of one:

enter image description here A random photo of such a truck, source

enter image description here source title: "a drag for ice road"

I guess, it should cost < $500K, which is 1% of what such plane cost before the sanctions were put.

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    $\begingroup$ Out of curiosity, if the ice in fact dangerously slippery, wouldn't that likely actually be beneficial unless emergency braking was required? Since the wheels on takeoff are essentially just there to support the plane. $\endgroup$
    – Chuu
    Sep 25 at 20:00
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    $\begingroup$ @Chuu The wheels also provide steering, especially the ability to maintain one's lateral position on the runway surface in the presence of crosswinds. $\endgroup$ Sep 25 at 20:27
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    $\begingroup$ Good answer. My only query I guess would be starting the plane when it's that cold, but I would guess that is a matter of portable generators and engine heaters? Would increase the costs of the operation but as stated, I guess by not a significant amount compared to the value of the aircraft. $\endgroup$
    – ThaRobster
    Sep 26 at 8:58
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    $\begingroup$ @ThaRobster in Novosibirsk, aircrafts are often parked for night, and I guess they must be cold as ambient temperature by morning. I didn't hear from pilots that it takes some special equipment to cold start them. In the worst case, there are "heat guns" -- big tube, large like suitcase, with conducting spirals that heat up, and a big fan. $\endgroup$
    – culebrón
    Sep 26 at 9:48
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    $\begingroup$ "And normal snow isn't slippery at all" - this is why I hate when they pour salt on footpaths here in the winter, it turns it into an dirty slush that ruins your boots, instead of the perfectly walkable packed snow. $\endgroup$
    – pipe
    Sep 26 at 9:59

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