How cold do parked aircraft get and can that cause damage?

[Eboy]

I'm sorry if I'm not using the right terminology. I'm thinking of an aircraft that's in service but parked at an airport overnight. If it's very cold it can get below freezing in the aircraft, which could freeze and burst water pipes. Or, are aircraft in those conditions kept warm so that doesn't happen? Just curious.

[Innominate]

The air temperature at cruising altitudes will be far colder than anything on the ground, although obviously in the latter case the engines would supply heat. The fuselage has some insulation, so unless an aircraft was left parked for several days in the Alaskan winter I doubt whether the cold would cause too many problems.

[wiggy]

Most aircraft manuals (either flight crew and/or engineering ) will somewhere contain a procedure usually done by maintainance personnel for draining of potable water tanks and lines etc, in the event it is known the aircraft is going to be left unattended for a considerable length of time in very cold conditions....in my experience that is generally not done for a night stop unless it is really really cold....the cheaper option then is probably to use an external heat source to keep the internaltemperatures at a reasonable level.

[vctenderness]

There was an interesting segment of the BBC2 series City in The Sky showing how they protect aircraft from extreme cold in Russia.

I'm sure someone on here will be able to provide the link.

[ExXB]

In the days of piston engines ground crews in Northern Canada would often have to pre-heat the engines using blow torches. Pesky things don't work with frozen oil.

See if you can find the thread in R&N/s about LX's diversion to Iqualit. That was an issue!

[Wodrick]

A/c can and do freeze in a cold soak condition on the ground. Normal practice is to drain the Potable water system if a cold soak is forecast.
The pipework outside the conditioned area is heated in the air to maintain it above freezing. (Airbus certainly,dunno Boeing)

In days of yore the Comet used to freeze for England.

[Swedish Steve]

Here in Stockholm it gets below minus 10 deg C regularly. All aircraft that are left outside unattended have the water system drained. We drain ours when the forecast is Minus 5degC or lower.
But aircraft that are parked on the F pier or Terminal 2, can have conditioned air supplied continuosly, and in that case the water is not drained.
One night a B737 had the heater hose fall off, and was not noticed. The tank froze and we had to park the aircraft in the SAS hangar for 8 hours to defreeze it!

[pulse1]

In days of yore the Comet used to freeze for England.

One of my instructors, also in days of yore, used to fly the Comet 3 at Boscombe Down. He regularly flew to Northern Canada and leave the aircraft to cold soak for a period. After the cold soak, they had to start up and be in the air with all systems working within a certain time. They then flew down to New Mexico and repeated the exercise after a hot soak.

[NutLoose]

Piston engines on large aircraft also used fuel dilution of the oil where petrol was used to thin it out, the fuel boiling off as it warmed up, also they had what was called a hot pot in the oil tank, this was like a cylindrical colander and the return warm oil would enter one end and the engine supply left the other end, this enabled a portion of the oil to heat up quickly and supply the engine, as it warmed up the heat would radiate out into the tank and the rest of the oil would then flow through the holes of the colander and be available to the engine.

As for jets, I did an engine change outside on the pan in Gander Newfoundland at -15, it dropped to well below that at night, bottle water in the galley had all blown and the caps were frozen on stalks of water as it pushed out of the bottles. We had to leave all the connections slightly loose as in those temps it was easy to break something, then once it was running and got some heat through it we went round and tightened up all of the connections. We then pressurised the cabin with the door partially cracked open to get some heat through the cabin. The aircraft had been sitting outside for four days like that. We then flew back in it that day. Ohh and yes it was cold.

[Denti]

Draining potable water is normal procedure on our planes here in germany in winter. Kinda dangerous during the walkaround next morning on the huge ice patch below the tail of the plane...

[Mr Mac]

Back in the 90,s I had a job in Edinburgh and was a regular on the Short 360 out of LBA - forget the carrier but I am sure someone will be along to remind me (Gill Airway's anyone, just remembered !). I also had few times in winter on the 06.30 depp where there was heavy frost on the ground, and the A/C was like an ice box (despite air blowers being used), you did not seem to get any warmth until abeam Carlisle ! Flying in colder climates which I have also done my fare share of, the carriers always seem to pre heat A/C but Gill Airways and LBA obviously did not always factor in the vagrancies of UK weather some mornings, well that's what it felt like anyway.

[Wodrick]

Draining potable water is normal procedure on our planes here in germany in winter. Kinda dangerous during the walkaround next morning on the huge ice patch below the tail of the plane...

Years and years ago, maybe 20, that practice was banned at Manchester and we had to drain into a tank.

Towards the end of my career, in Maintrol, there was a succession of phone calls from the outstations,every night when a frost was forecast "do you want it draining tonight ?" Buggered if you did, buggered if you didn't

[PAXboy]

I recall a (horribly) early start out of LHR in winter a few years back. The FC said that we had to spend a couple of minutes in the run up bay near the end of taxi way, before turning onto the active. They said, as first operation of the day and the cold night, they needed to give the engines longer to stablise. Otherwise, early starts are unremarkable - from the pax perspective.

[Piltdown Man]

Eboy - Water is one of the things that can cause an aircraft damage when parking overnight. We solve that by dumping the remaining water before we land. Later on, when the aircraft is first connected to ground power heaters warm the water system, including the filler nipple, to prevent it from freezing. It definitely works down to minus 27C. The heaters cycle through various schedules all the time the aircraft is powered. The other items are the brakes, that are left off, and and the batteries. The aircraft's manuals state how the batteries should be handled although it is generally easier and cheaper to keep the aircraft powered during a nightstop.

[CelticRambler]

In the days of piston engines ground crews in Northern Canada would often have to pre-heat the engines using blow torches. Pesky things don't work with frozen oil.

If the OP wants to work through episodes of the Buffalo Airways "reality" series, there's at least one episode devoted to getting one of their aircraft warmed up enough to fly.

[Dairyground]

I seem to recall mention in the distant past of draining the oil from a piston engine whilst it was still warm enough to flow, then in the morning starting up without oil (which would heat things up very rapidly) and pour the oli in once things were running. My source could have been "Biggles Flies North" of some similar tome, but I would be interested to know if the procedure was based on reality.

[PAXboy]

I seem to recall that the process of draining oil from a piston engine and then pre-heating the oil before returning to the engine - critically starting the engine and then tipping the pre-heated oil in a second later! was described by Nevil Shute in An Old Captivity.

[pax britanica]

If I remember correctly the City in the Sky program on Russia shopwed the ground crew pouncing on the wheels as soon as it was on stand to put upa sort of blow up tent around the tires even on turnaround -I think they and or the brakes stil had some nheat from the landing and they wanted to capture that but they wouldn't let the tyres cool , it was like minus 33 where they were, even on a turn around let alone overnight

[ExXB]

Could have been here.

https://www.amazon.com/Bush-Pilot-Briefcase-Incredible-McConachie/dp/1550545868

[Kewbick]

The Herman Nelson Engine Pre-Heater has been used for decades in Canada.
http://i1047.photobucket.com/albums/b477/gumpjr_bucket/Herman%20Nelson.jpg

[Kewbick]

Canada's Cold Weather Testing Establishment determined that air-cooled piston engine operation at low rpm, i.e. idling and taxiing, is not recommended in surface temperatures lower than -38C. Baffle plates installed ahead of the cylinders reduce the effect of cold air engine blast to a small degree. Potable/fresh water systems should be drained in anticipation of extended below-freezing soaks. Portable electric heaters can be used to warm the cabin.
http://i1047.photobucket.com/albums/b477/gumpjr_bucket/engine%20preheat.jpg
Typical engine pre-heater in use. Note this Cessna 207A Stationair 8 has anti-gravel protector flaps installed immediately aft of the main wheels.

[talkinair]

Draining potable water is normal procedure on our planes here in germany in winter. Kinda dangerous during the walkaround next morning on the huge ice patch below the tail of the plane...



Not sure on airliners, but modern business jets have the ability to purge the water lines while in flight. That minimizes the skating rink on the ramp.

In addition, any liquid needs to be given consideration...Perrier, cans of Coke, bottles of Champaign, etc.

My AFM has a chart that shows outside air temp vs. hours on the ground.
Follow the two selected columns to your answer of how often you must run the Aux Power Unit/Cabin heaters to preclude water system freezing. A heated hangar simplifies the whole process, but some places do not offer such luxuries.