[jandrese]

Old farm tractors used what was called "farm oil" in the old days. Basically the cheapest form of fuel you could buy since it was effectively a byproduct of the refining process. It was closer to paraffin wax than diesel, solid at room temperature. In order to start the tractor there was a second tank with diesel that was used until the engine warmed up enough to melt the primary fuel. If your tractor stalled out and you couldn't get it started again quickly the fuel would solidify in the lines and you would have to light a fire under the tractor to get it started.

[greglindahl]

Is this the same as the "bunker oil" burned by big ships? Wikipedia seems to think so: https://en.wikipedia.org/wiki/Fuel_oil#Bunker_fuel

[dredmorbius]

Yes.

The WWII Liberty Ships utilised a triple-expansion steam engine, fired by bunker fuel. Both the expended steam and the boilers were used to fluidise the fuel to flowable tempertures -- the steam circulating either through or around the feed tanks, and the fuel line itself passing through the boiler and flame trench before final injection.

There are two remaining Liberty Ships in the US -- the John W. Brown in Baltimore, and the Jeremiah O'Brien in San Francisco.

Pay a visit and one of the engine-room crew can tell you the details.

The generaly kluginess and hackiness of the design instantly brought to mind what many software projects I've worked on might look like if physically instantiated. Though the Liberty Ship design is by far the more robust and useful than most.

[frank2]

American liberty ships used steam engines because US industry had been building cargo ships for the Brits and wanted to avoid the delay of switching to a more modern design. The Brits specified steam engines so they could run the ships on coal so they wouldn't have to import the fuel.

[fencepost]

The more modern takes on this likely include "greasecar" diesel conversions that still have a small diesel tank, plus the different summer and winter blends of diesel fuel itself (since "A" diesel that gels at 5C is going to be a problem in a lot of places).

[WalterBright]

The Germans in Russia in WW2 would use fires to warm their tanks and airplanes to get them to start.

[jacquesm]

They still do this in some places in Russia.

[WalterBright]

I might add that lighting a fire under a gas engine that likely has leaks and drips is a pretty ballsy thing to do.

[jacquesm]

Usually done for big rigs, diesels not gas engines.

[WalterBright]

Airplane engines are gas!

[jacquesm]

I didn't have airplane engines in mind when I wrote that (tanks = vehicles) but given the thread context and your airplanes reference I see how that could happen, same thing with 'block heaters' elsewhere in the thread, I take it that is in the context of other vehicles (heavy equipment, tractor-trailers, buses and so on).

And yes, some airplane engines use gas but the majority of them runs something that in constituency is closer to regular diesel than to gas.

Kersone is #1 diesel!

AV gas is another matter entirely but I'm not aware of any jet that would use it, though that might be a fun thing, and given that turbines can run on almost anything combustible it will probably work to some extent but I don't think it will be a happy ending unless the engine is really designed for it.

Btw, this is an interesting start-up: https://www.youtube.com/watch?v=ESdHyNtHpqs not cold weather but I'd hate to fly that in any conditions.

[inferiorhuman]

Airplane engines are gas!

Sure, small ones with piston engines. Sure. Most anything running a turbine uses Jet-A which is closer to kerosene / diesel than gasoline.

If you're leaking fuel you've got bigger problems than how to safely heat up the engine.

[dehrmann]

Modern prop planes tend to use high-octane gas. Jets use jet fuel (kerosene), which is really a light diesel.

[kortilla]

It’s rare to have an engine that just drips fuel. Lubrication oil for sure, but straight up petrol leaks for a non-running engine require a lot of things to be wrong.

[WalterBright]

You're talking about a very heavily used airplane in a barely usable airfield with desperate mechanics, often under attack, adverse weather, and parts shortages.

[weaksauce]

Or an sr-71

[grogenaut]

hey at least they decided not to use hypergolic fuel in the sr-71 tho having a jet that was on fire all the time would be pretty bad ass looking. Titanium would probbably handle it and it'd eventually warm up the skin and close the gaps.