brooksmoses: (Default)
[personal profile] brooksmoses
I just posted a comment on a blog post about a rather odd experimental dirigible from 1929, and thought some people here might be entertained as well.

One of the many odd things about the dirigible in question was the propulsion mechanism -- instead of a conventional propeller, it basically had a radial impeller mounted on the front of the hemispherical nose, with the intent that the impeller would pull air from in front of the dirigible and blow it outward along the nose in all directions. The expectation was that the airflow would then follow the surface backwards along the dirigible to the tail making a sort of envelope around the whole body -- and because it was this thin sheet of high-speed air, the tail surfaces could be quite small indeed.

This is, in point of fact, nuts. It is, however, not quite as far-fetched as it sounds; airflow will follow surfaces like that in the right conditions -- it's just that rather low-speed flow around a riveted overlapped-strake dirigible body (I said it was odd, yes?) is not the right conditions.

Anyway, there's a bit of personal history here -- and, yes, it does involve a genuine patent by my father and a coworker for a flying saucer. Quoting my comment:
Of course, aside from all the other flaws in that propulsion idea, it's preposterous that a 150hp engine would be sufficient to propel something that large at those sorts of speeds.

The basic propulsion idea did look awfully familiar, though.

I have memories, as a child, of visiting the university research lab of one of my dad's coworkers, where they were working on testing out this contraption: https://www.google.com/patents/US5054713. In short, the basic idea was to replace the impeller by a jet engine and appropriate nozzle, turn the whole thing 90 degrees so the engine pointed upwards, and leave off the back half -- thereby producing a VTOL airplane that looked very much like an upside-down salad bowl. As with Slate's design, the idea was that very small control surfaces in the flow could be used to effectively control the craft. The patent has a sketch of the static test apparatus, which IIRC was about five feet in diameter.

Obviously the idea never went anywhere -- but then, what 1980s VTOL concept did? My impression is that the basic ideas were reasonably sound: the airflow did indeed stay attached to the surface except where the control surfaces intentionally detached it, and the small control surfaces were reasonably effective. Where it completely failed, of course, was on practicality, and on being any better than more conventional options.
I think I may need to get a copy of the patent drawings printed up for my office.

Date: 2013-09-16 05:15 am (UTC)
From: [identity profile] suzanne.livejournal.com
I fully endorse getting a copy for your office.

Date: 2013-09-16 11:16 am (UTC)
From: [identity profile] quercus.livejournal.com
I read that and my first thought was "Coanda"

Profile

brooksmoses: (Default)
brooksmoses

October 2024

S M T W T F S
  12345
6789101112
1314 1516171819
20212223242526
2728293031  

Style Credit

Expand Cut Tags

No cut tags
Page generated Jul. 13th, 2025 08:35 am
Powered by Dreamwidth Studios