A new paradigm for new cars

sounds like my laptop. I get all these Windows updates…but they never integrate, just make the laptop run slower.

Apparently a there’s a battery temperature sensor beneath the battery.

CSA

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I remember reading about a plane failure, by memory it was in the late 30’s or early 40’s, they flew passenger planes to Hawaii. Pilots can put me in the correct decade for that.

It had more than one engine all right, but when one failed, they could not go high enough and fast enough to make it across the ocean to Hawaii. Because fuel consumption increased at lower altitudes, I guess.

So, they got on the radio and arrangements were made to locate a landing site on the ocean with one or more nearby ships. It was fortunately daytime, and good conditions. So, they set down carefully, and everyone got off that plane and into a life raft before the plane sank. Not one person was lost.

This is not something I would want to bet on. :smiley:

Really rough explanation (my portion, see below), but basically the colder temperatures at higher altitudes helps the engines work more efficiently:

Burning the fuel-air mixture heats it and makes the gas expand. This happens at nearly constant pressure and in a restricted volume, so the only way to make room for this expansion is for the gas to flow faster. Nearly constant pressure means that the density of the gas must decrease. The density ratio between the heated and the unburnt gas is proportional to its temperature ratio, measured in absolute temperature.

However, the amount of fuel burnt determines the absolute temperature increase, the difference in degrees between the burnt gas inside the combustion chamber and the unburnt gas at the intake. For a given amount of fuel, the temperature ratio which can be achieved with an absolute temperature increase becomes smaller the higher the temperature of the unburnt gas is. Thus, efficiency decreases with higher temperature of the intake air.

Really good article: airliner - Why do jet engines get better fuel efficiency at high altitudes? - Aviation Stack Exchange

I do not feel qualified to state an opinion, at this hour of night. But, the planes flying to Hawaii in the 30’s and 40’s were not jets.Not sure that matters in your theoretical explanation, just want to be clear.

Airplanes get better gas mileage at high altitudes for much the same reason cars get better gas mileage at high elevations. There is less air resistance in the thin air at high altitudes. At space shuttle altitudes, there is zero air and the space ship just coasts around the earth with the engines completely shut off.
In the thinner air, there is less wind resistance, but there is more induced drag from the wings, induced drag goes down as the air speed goes up while friction drag goes up as air speed goes up. The best lift to drag ratio happens when friction drag = induced drag. So the higher you go, the higher the true air speed where the best lift to drag ratio occurs, although the indicated airspeed stays about the same.
That’s the main reason aircraft instruments display uncorrected indicated airspeed instead of true airspeed. If the plane stalls at 100 knots indicated air speed near the ground, it will stall at 100 knots indicated airspeed at 40,000 ft.
The indicated airspeed of the space shuttle in orbit would be zero, even though it is traveling at around 5 miles per second.

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I think your Hawaii bound airliner was a Pan American Boeing 377 Stratocruiser (military C-97) PAA 943 that turned back due to a runaway propeller and shut down number one engine in 1956. It ditched close to a Coast Guard cutter with everyone saved. It is documented in the March Smithsonian Air & Space magazine which is available on-line.

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A windmilling propeller is like a parachute. Lots of drag.

Sounds right to me. Hey, I was only off 20 or 30 years. I must be improving in my old age…

It sounds as if the John Wayne movie “The High and the Mighty” has many similarities to this incident, except in the movie they didn’t ditch

Here’s a link to an account of what happened on Pan Am flight #6 The pitch control on the propeller of engine # one failed causing engine # one to uncontrollably overspeed when the power was reduced for cruising. The pilot decided to shut down the engine but because he was unable to feather the prop, it kept windmilling anyway putting a tremendous drag on the airframe.