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Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

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Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#101

Post by dnemmers »

egberts1 wrote: post #97

Ummmm. In 2007, near a certain defense contractor, we demonstrated a 319'-wire trebuchet mounted horizontally but slight vertical a-skewed for distance/aiming. Used a gnarly large helical gear but with integral diminishing ratio. Gravity-powered in same way but with a 20-meter-ish tower. (Cheaper than a standard 800'-tall trebuchet.) At release time, achieved 10 G-force (payload goal), it's velocity speed was audibly…

Would love to see some photos in action, but 2007..defense contractor...makes me think photos may have been frowned upon.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#102

Post by felooboolooomba »

egberts1 wrote: post #97

Ummmm. In 2007, near a certain defense contractor, we demonstrated a 319'-wire trebuchet mounted horizontally but slight vertical a-skewed for distance/aiming. Used a gnarly large helical gear but with integral diminishing ratio. Gravity-powered in same way but with a 20-meter-ish tower. (Cheaper than a standard 800'-tall trebuchet.) At release time, achieved 10 G-force (payload goal), it's velocity speed was audibly…

Good old days. I'd love to see the design for that one. Any chance?

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#103

Post by duxup »

pjerem wrote: post #87
SkyMarshal wrote: post #86

Earlier quoted context omitted.

Still, why link some blog post about it instead of the actual source.

Because HN will downvote videos regardless its quality.

The amount of YouTube spam has really made submitting YouTube links just about anywhere a bad idea.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#106

Post by Gravityloss »

mncharity wrote: post #73
Gravityloss wrote: post #62

There were designs to hurl masses from the Moon also with a sling. Massively less infrastructure than a linear mass driver.

Like [1]. But for an "oh, that's cute", here's [2] Launching mass from the Moon helped by lunar gravity anomalies (2024). The Moon's gravity field has lumps (mascons), so low lunar orbits are unstable (increasingly elliptical until ground impact; timescale months; thus satellites requiring powered stationkeeping even with no atmosphere). Paper observes you can run the path in reverse: elliptical ground launch gets so…

That's absolutely incredible. I would never have thought of that. Thanks!

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#107

Post by itronitron »

27183 wrote: post #71
itronitron wrote: post #60

Earlier quoted context omitted.

The spiral drivetrain seems like the most innovative, and elegant, technology that could be built with old tech. It requires some very strong rope though, so if you went back in time you'd need to really focus on that.

Hemp ropes are quite strong, they've proven themselves for thousands of years in marine applications. You definitely need more thickness to achieve the same breaking strength as dyneema or steel cable but at slower speeds and higher projectile masses the aerodynamic consequences of a thicker sling rope might not matter so much. As for the "drive rope" for lack of a better term (the one that transfers power from the f…

>> at slower speeds and higher projectile masses the aerodynamic consequences of a thicker sling rope might not matter so much.

You make an excellent point.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#108

Post by egberts1 »

dnemmers wrote: post #101
egberts1 wrote: post #97

Ummmm. In 2007, near a certain defense contractor, we demonstrated a 319'-wire trebuchet mounted horizontally but slight vertical a-skewed for distance/aiming. Used a gnarly large helical gear but with integral diminishing ratio. Gravity-powered in same way but with a 20-meter-ish tower. (Cheaper than a standard 800'-tall trebuchet.) At release time, achieved 10 G-force (payload goal), it's velocity speed was audibly…

Would love to see some photos in action, but 2007..defense contractor...makes me think photos may have been frowned upon.

Done on company property. Design Owned by company. We did not object for maximum marketing.

Re: Tom Stanton's supersonic trebuchet breaks sound barrier with gravity alone

#109

Post by egberts1 »

felooboolooomba wrote: post #102
egberts1 wrote: post #97

Ummmm. In 2007, near a certain defense contractor, we demonstrated a 319'-wire trebuchet mounted horizontally but slight vertical a-skewed for distance/aiming. Used a gnarly large helical gear but with integral diminishing ratio. Gravity-powered in same way but with a 20-meter-ish tower. (Cheaper than a standard 800'-tall trebuchet.) At release time, achieved 10 G-force (payload goal), it's velocity speed was audibly…

Good old days. I'd love to see the design for that one. Any chance?

Napkin, someone literally used it at lunch time.

Some of us ribbed him: "Destruction of classified material!", "call Security!", "PM's (program manager) behind you".

No. Wasnt classified, but company-owned.

There are clues above.

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