5 ms·

This might be from the later Brian Herbert books, but I recall ornithopters having jets or thrusters for VTOL.

lrem 5y ago
TFA is citing jets from the original Dune novel.
Animats 5y ago
Thrust-based VTOL requires huge amounts of engine power. Which is why it's rarely seen on anything other than fighters, which are mostly engine anyway. There were some exceptions in the 1940s and 1950s, when jet engines didn't quite have enough power to get aircraft up to flying speed quickly. There were some attempts to use rocket-assisted takeoffs ("RATO" or "JATO") during WWII, and by the 1950s, this worked reasonably well. This peaked with the B-47 bomber, which was basically a jet fighter scaled up to heavy bomber size. Here's a JATO-assisted B-47 takeoff.[1] And here's a jet fighter zero-length takeoff from a rack on the back of a truck.[2] That was pushing it; there were a lot of crashes. Awesome, but impractical, the technology was discarded in favor of aircraft with enough main engine power to get off the ground on short runways. Another dead end was the Avro-Car, which was supposed to be a VTOL for the Army. This is the famous flying saucer.[3] It was supposed to be a supersonic VTOL. It had nowhere near enough power for that, and could barely get out of its own ground effect. Plus it was unstable, although today it could probably be stabilized automatically. The prototype finally ended up at what's now NASA Ames, bouncing around the back lots in hovercraft mode. The U.S. Army was also funding the UH-1 helicopter, which was less awesome, but far more useful, so they cancelled the Avro-Car and ordered lots of Hueys. If you like weird VTOL craft and are in Silicon Valley, visit the Hiller Aviation Museum. Many of those strange ideas from the 1950s ended up there. So, using a booster to get a large ornithopter off the ground is, while not impossible, probably not something you'd do often. Although you could imagine some fortress having such a rig, so the leaders could escape when they were losing. [1] https://www.youtube.com/watch?v=vKQYG_fA2uM https://www.youtube.com/watch?v=vKQYG_fA2uM [2] https://www.youtube.com/watch?v=uxazX7Z_4iQ https://www.youtube.com/watch?v=uxazX7Z_4iQ [3] https://en.wikipedia.org/wiki/Avro_Canada_VZ-9_Avrocar https://en.wikipedia.org/wiki/Avro_Canada_VZ-9_Avrocar
- Andrew_nenakhov 5y ago
  The baron was flying by himself, so in that universe they definitely had other ways to generate lift but trust-based propulsion.
  - dragonshed 5y ago
    Suspensors aren't really used for thrust, but as a way to augment or nullify the effect of gravity on an object. In the books, the kernel of fictional science used for multiple effects, including suspensors which is what the Baron uses, is called the Holtzman Effect [1]. The movie doesn't mention it at all, but the depictions of suspensors with all the massive vehicles, as well as floating furniture, glow globes, etc, are all consistent with how the books describe them. [1] https://dune.fandom.com/wiki/Holtzman_Effect https://dune.fandom.com/wiki/Holtzman_Effect
    - Andrew_nenakhov 5y ago
      I didn't say 'thrust', I said 'lift', and suspensors did lift the baron. It could be used to lift ornithopters as well, so it could, you know, flap wings for propulsion.
      - arpa 5y ago
        trust != thrust, just so you know.
        Andrew_nenakhov 5y ago
        Tell it to autocorrecting keyboard on my android.
        arpa 5y ago
        That's what happens when you put your trust in autocorrect: you lose all the thrust )))) I've turned off the autocorrect, and now I get all kinds of stupid touch interface mistypes, and lose time over correcting them, but at least i'm not miscorrected all the time.

lrem 5y ago

TFA is citing jets from the original Dune novel.

Thrust-based VTOL requires huge amounts of engine power. Which is why it's rarely seen on anything other than fighters, which are mostly engine anyway. There were some exceptions in the 1940s and 1950s, when jet engines didn't quite have enough power to get aircraft up to flying speed quickly. There were some attempts to use rocket-assisted takeoffs ("RATO" or "JATO") during WWII, and by the 1950s, this worked reasonably well. This peaked with the B-47 bomber, which was basically a jet fighter scaled up to heavy bomber size. Here's a JATO-assisted B-47 takeoff.[1] And here's a jet fighter zero-length takeoff from a rack on the back of a truck.[2] That was pushing it; there were a lot of crashes. Awesome, but impractical, the technology was discarded in favor of aircraft with enough main engine power to get off the ground on short runways. Another dead end was the Avro-Car, which was supposed to be a VTOL for the Army. This is the famous flying saucer.[3] It was supposed to be a supersonic VTOL. It had nowhere near enough power for that, and could barely get out of its own ground effect. Plus it was unstable, although today it could probably be stabilized automatically. The prototype finally ended up at what's now NASA Ames, bouncing around the back lots in hovercraft mode. The U.S. Army was also funding the UH-1 helicopter, which was less awesome, but far more useful, so they cancelled the Avro-Car and ordered lots of Hueys. If you like weird VTOL craft and are in Silicon Valley, visit the Hiller Aviation Museum. Many of those strange ideas from the 1950s ended up there. So, using a booster to get a large ornithopter off the ground is, while not impossible, probably not something you'd do often. Although you could imagine some fortress having such a rig, so the leaders could escape when they were losing. [1] https://www.youtube.com/watch?v=vKQYG_fA2uM https://www.youtube.com/watch?v=vKQYG_fA2uM [2] https://www.youtube.com/watch?v=uxazX7Z_4iQ https://www.youtube.com/watch?v=uxazX7Z_4iQ [3] https://en.wikipedia.org/wiki/Avro_Canada_VZ-9_Avrocar https://en.wikipedia.org/wiki/Avro_Canada_VZ-9_Avrocar

Andrew_nenakhov 5y ago
The baron was flying by himself, so in that universe they definitely had other ways to generate lift but trust-based propulsion.
- dragonshed 5y ago
  Suspensors aren't really used for thrust, but as a way to augment or nullify the effect of gravity on an object. In the books, the kernel of fictional science used for multiple effects, including suspensors which is what the Baron uses, is called the Holtzman Effect [1]. The movie doesn't mention it at all, but the depictions of suspensors with all the massive vehicles, as well as floating furniture, glow globes, etc, are all consistent with how the books describe them. [1] https://dune.fandom.com/wiki/Holtzman_Effect https://dune.fandom.com/wiki/Holtzman_Effect
  - Andrew_nenakhov 5y ago
    I didn't say 'thrust', I said 'lift', and suspensors did lift the baron. It could be used to lift ornithopters as well, so it could, you know, flap wings for propulsion.
    - arpa 5y ago
      trust != thrust, just so you know.
      - Andrew_nenakhov 5y ago
        Tell it to autocorrecting keyboard on my android.
        arpa 5y ago
        That's what happens when you put your trust in autocorrect: you lose all the thrust )))) I've turned off the autocorrect, and now I get all kinds of stupid touch interface mistypes, and lose time over correcting them, but at least i'm not miscorrected all the time.