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Comment by tialaramex | Hacker News Reader

I wouldn't be surprised if there are some pilots who learned in a small (prop) jet at this point. Such planes are not cheap, but they do exist and it's not as though the airline wants you to have specifically piston experience because the airline only owns jets anyway.

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You can rent a small prop plane like a C152 for less than $100 an hour in the US in some places.

I would be surprised if there's a turbine out there that can be rented for less than $1000.

There are plenty of commercial passenger prop planes flying today. For example, Billy Bishop Airport (YTZ) on Toronto Island only permits prop planes because of the close proximity of the airport to the city, and nearly 3 million passengers pass through YTZ each year, mostly with Porter, a regional airline.

Maybe this isn't obvious to frosted-flakes, or to some other readers:

The propeller on a prop plane can be attached to either a piston or a jet engine. (Or mostly in smaller or experimental planes, an electric motor)

So, in the example of Porter, those are Dash-8s and that's a jet engine. Yes it has the propellers on the front like those old-timey aeroplanes you saw in black and white, but you'll notice that the propellers are on the front of a jet engine. See, the engine needs spinning blades inside it to work, compressing air to run the engine, but you can choose whether to expend the resulting energy on producing yet more spinning motion for propellers (a turboprop engine) or to shove lots of fast air out of the back (a turbofan engine)

A jet engine does not use leaded gasoline, that would be crazy. Whether it is spinning a propeller or just shoving fast moving air out the back, the jet engine runs on kerosene. This is still nasty stuff, but it does not have lead in it.

Funny, I had a vague understanding of that before writing my comment, but somehow I glossed right over it and equated props with piston engine.

Technically speaking, the engines you are referring to are turbine (not jet). There are two types of turbine engines: turbojets and turboprops. The first ones produce a significant portion of the thrust via jet exhaust (even though high bypass jets are close to prop engines). Even turboprops (like the popular Garrets and PT6's) produce about 10 percent of their thrust through jet exhaust.

To be even more technical, the difference between turbine and piston engines is in the combustion chamber: open combustion in the case of a turbine and closed in the case of a piston.

Finally, there are turbine engines that run just fine on LL100 (leaded avgas). Garrets, for example. One can even mix gas and jet-A in those. It is not recommended to run avgas for more than 1000 hours though due to potential issues with lead deposits. Some military jets engines are designed to run on almost anything combustible except maybe coal dust (I am exaggerating somewhat, of course).

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