Are TL4 'Rocket-Pack's Possible?

[Ulzgoroth]

Originally Posted by acrosome

Things much like that have actually been tried, and they have an unmitigated record of failure. Explosive failure. Eventually, a spark gets back into the powder tank, and boom. It's much harder to get valves to seal well with solids than with liquids or gases.

That being said, that's an awful lot like how a pulse jet works. If you want potentially low-tech powered flight, a valveless pulse jet is about as simple as they come. And you can run one on almost any combustible fluid (with varying efficiencies, of course). One is forced to wonder how well various alcohols would work? I know that a lot of hobby designs run on diesel, so I wonder if vegetable oil would work? (Given the well-known trivia that the first diesel engines ran on peanut oil.)

Anyway, there are all sorts of YouTube videos about them.

One problem- they do need something like a spark plug.

Another problem- how exactly would a TL4 designer have thought to make the damned thing?

The Wikipedia article suggests that you don't actually need a spark plug. Supposedly after initial ignition subsequent pulses will self-ignite from compression and reactive residue from previous pulses. So you could fire the thing with a flintlock mechanism or similar.

[Fred Brackin]

Originally Posted by Kromm

For example, this.

I don't suppose "Wan Hu" translates as "Buster". :)

The Mythbuster's experience with recreating this one would tend to show that the trail and error process was too hard on crash test dummies never mind test pilots.

[Bruno]

Originally Posted by Fred Brackin

I don't suppose "Wan Hu" translates as "Buster". :)

The Mythbuster's experience with recreating this one would tend to show that the trail and error process was too hard on crash test dummies never mind test pilots.

They comment in subsequent episodes that the only recoverable part of Buster was the scarred and burnt rubber face, which they stapled on the next Buster for continuity.

[DanHoward]

Originally Posted by Bruno

TL 0 is an immense slice of human history, and the Aborigines have been in Australia for 40 thousand years.

The latest finds put the earliest aboriginal habitation of Australia at closer to 60,000 years.

[Anthony]

Originally Posted by Ulzgoroth

The Wikipedia article suggests that you don't actually need a spark plug. Supposedly after initial ignition subsequent pulses will self-ignite from compression and reactive residue from previous pulses. So you could fire the thing with a flintlock mechanism or similar.

For a simple set up, you probably want fuel that aerosolizes easily and has a fairly low ignition temperature. Looking at a list of alchemical substances, diethyl ether is probably the most promising.

[Black Leviathan]

If Alchemy is a factor you could have early access to rigid lacquers or enamels that would make for a much lighter airframe than cloth and wood, perhaps even crude airfoils. Divinci demonstrated that he understood the concept well enough at TL4 to build his model birds, he just lacked the materials.

[Anthony]

Originally Posted by Black Leviathan

If Alchemy is a factor

I was talking about actual historical alchemy, not fantasy alchemy.

[Bruno]

Originally Posted by DanHoward

The latest finds put the earliest aboriginal habitation of Australia at closer to 60,000 years.

Ooo I'll have to look into that.

[Flyndaran]

Please send me a PM if you find links. All I can find suggest that all evidence from earlier than 40k BP is quite sketchy.
But my search skills are mediocre.

[scc]

Originally Posted by Flyndaran

Please send me a PM if you find links. All I can find suggest that all evidence from earlier than 40k BP is quite sketchy.
But my search skills are mediocre.

Have you tried Google?