"Why I dislike most scifi lifters." Topic

You see them all the time, sci fi versions of helicopters. They look just like helicopters but they have 2 or 4 nacelles on the side that look like jet engines. Do the designers know why you cant replace a helicopters top mounted engine and rotors with VTOL vehicles with jet engines?

Jet engines need a large intake and exhaust to work. In flight this is no big deal as long as the doors are closed and nothing is sticking out the side, like say a door gunner with gun. Yet when they go to land the nacelles point straight down. What happens when a jet blast hits the ground, it bounces back up and out. So no exiting the vehicle by rope, unless you like rappelling into a blast furnace.

The same goes when the vehicle lands. You open the side door and get a blast of super heated air into the inside. You cant exit unless the engines are shut down, yeah get a pilot to shut his engine down in a hot LZ. No one stands under a Harrier or F-35 when they land or take off. In fact the Navy found out that the F-35 when operating in vertical take off mode tended to melt the carrier decks.

Then you get the response that the nacelles are anti-grav or something similar. Does that mean the nacelles lift the vehicle by creating an opposing force of 20 or 40 tons or however much it weighs, underneath the craft. So standing under the vehicle will subject you to 20 tons of force pushing you down.

Perhaps the nacelles just cancel out the mass of the vehicle and all on board. So as a passenger while the anti-grav is working means you are floating around inside, unless strapped in.

So sorry, I just prefer my future lifters to be just advance helicopters. Why mess with something that works. I much prefer to see future versions of the Osprey or Blackhawk then a bladeless lifter.

Hmm… VTOL lands and pilot immediately engages/opens reverse thrust clamshells to re-direct the (now somewhere around idle) jet blast upwards.

You must consider Rule of cool. Sorry man, but the only thing more badass than a Hind is a sci-fi Hind.

Also, I think that players enjoy having something they can relate to the actual world in their miniature vehicles, yet they still want something about them to be sci-fi. Otherwise, why not just play moderns or near future?

Excellent topic… I have given a lot of thought to this.

Take, for example, the Sparrowhawk-class Light Assault VTOL:

As you can see, each side has space for two soldiers. Of course, since the craft is low orbit capable, any soldier hitching a ride must be in a Type-Xv to Type-Xn fully enclosed, low-orb rated armored suit.

If you look at the nacelles, this model (the Anvitro Industries KNX-1070 SuperThruster©)has no intake but provides forward, backwards and Z axis movement. Some care must be taken when riders are on board, reducing maneuverability slightly, but otherwise gives a full range of motion.

The KNX-1070 operates on the principles discovered in 2114 by Dr. Salias Anvitro in which the localized higgs field is altered to create areas of "low-pressure" energy/matter interaction. Of course as is standard with this type of interaction you will have limited fine-tuned movements, but the directional plasma manifold solves this problem.

The Plasma Manifold operates within the 10Gv range, so range usually isn't an issue.

That is actually a good explanation MrHarold. All it takes is just a simple little explanation to make it work. Yeah I could see how the pilot has to be careful if he rotates the nacelles forward to stop forward motion and blows the passengers off.

It is just all those other designs where the thrusters point right down over the side doors, that drive me crazy.

Spleenrippa, that still doesn't help when you hover. Cant fast rope down into the blast. Rope will be blown all over the place, much less the guys going down. The great advantage of a helicopter is the ability to hover over a spot and deliver a pay load without frying everyone underneath.

The concept vehicle art genre is full of difficulties like this.

Maybe in the future we get some VTOL version of what amounts to a lifting body. However, I think they would not look at all like the "jet Mi24" that seems to be a particular darling of those designing what you talk about.

Without a lifting surface, fuel efficiency is highly in doubt as well.

When it comes to anti-grav, there are a ton of questions, none of which are answerable without knowing how it works. However, if anti-grav* is working by being an alternative form of propulsion and not a nullifier, then it's not necessarily any worse than a helicopter. That pressure is still likely distributed over an area, just like a tank doesn't necessarily sink in soft ground as the tracks distribute the weight.

Even pressure per area is high, presuming it's generated from nacelles and not hot, it could even be directed so the vehicle is lifted on 4 cones of pressure directed at away angles so that troops can rappel down a calm center.

We do need to be careful we don't limit our speculations too much or we look like those who said we'd never be able to manage heavier than air. On the other hand, Jules Verne thought a cannon would make a great launch platform for moon flights.

*-A term I hate: helicopters and air planes already are anti-grav if you're not limiting your self to nullification;.

The Sparrowhawk obviously has grav-plates in the sponsons, or the Type-X series of fully enclosed, low-orb rated armored suits, must be equipped with Posterior Positional Stability Nodes (aka butt magnets).

Wyatt

Just to turn this on it's head a bit…

I work on helicopters and have had to be around during hover refuels… it is no picnic under there unless you are hunkered down. You stand up and unless you are properly braced, you'll be tumbling across the bondu.

Yes, when they land, they normally reduce pitch… but they don't always land.

So even helicopters have down-force issues for the troops.

Further more, the harrier has a mix of cold eflux at the front and hot eflux at the back. Who's to say that a cold eflux system hasn't been put into the VTOLs? Venting the efflux could provide an alternative for shutting down the engines (when it is on the deck) too.

No matter what type of propulsion system there will always be some form of down-force issue… every action has an equal and opposite reaction… and all that.

Well, at least this discussion beats the old "mechs are unrealistic" threads we usually see.

I like this thread.

BTW I always look at it as no rotors means nothing to break off when picking up the small models. I've broken too many rotor blades over the years due to my clumsy hands.

The Sparrowhawk obviously has grav-plates in the sponsons, or the Type-X series of fully enclosed, low-orb rated armored suits, must be equipped with Posterior Positional Stability Nodes (aka butt magnets).

Wyatt

Actually both the back and the optional "backpack" have the universal coupling mechanism that allows for quick-disconnect and has a hold strength of 1 ton at 45Gs.

VTOL mecha with laser-swords that transform into VTOL space-fighters, armed with pea-shooters and infinite cluster missiles… with boobs.

MrHarold – 2nd the great description, I was reading it and thinking "Of course" to myself.

Maybe the nacelles could have electrically driven turbines instead of the engines themselves being within? Although you need to explain where the power comes from.

And Tibbles, you could always simply use a disc of clear plastic a I did for a couple of GZG microscale craft I had (they just look like helicopters! They look stupid without a rotor!)

MrHarold – 2nd the great description, I was reading it and thinking "Of course" to myself.

Haha, thanks!

The heat issue can be a concern.

That's why the troops deploying from them wear battledress, in order protect themselves from the brief exposure time to the searing heat.

"Does that mean the nacelles lift the vehicle by creating an opposing force of 20 or 40 tons or however much it weighs, underneath the craft. So standing under the vehicle will subject you to 20 tons of force pushing you down".

I've pondered this as well, and am still not sure which way to go.

On the one hand, I like the nullification concept, where it's really a non-issue, since gravity is a relatively weak force – otherwise, we couldn't move, run, or jump, and yet it is strong enough to keep us on the planet, and to kill us if we jump from too high a height.

For grav tanks though, I was also thinking it might be interesting if the grav fields did provide a proportional downward force onto the surface of a planet, and/or anything underneath it, when in close proximity to other objects.

If flying at treetop level, or above, this weight would be dissipated out over a reasonably large area.

However, at NOE, or near ground level, the gravitic field would be sufficient to crush some items underneath it, e.g. light building structures, personnel, etc.

That would certainly make grav armor assaults on defended positions a lot more interesting, and deadly, since those not in heavy bunkers would be at great risk of being crushed by the anti-gravity field used to hold the heavy armor aloft.

So sorry, I just prefer my future lifters to be just advance helicopters. Why mess with something that works. I much prefer to see future versions of the Osprey or Blackhawk then a bladeless lifter.

Well, for folks like you, we had a ducted fan version of the Phalanx gunship designed.

The first version to be out will be the grav Phalanx however, either with door gunners or buttoned up, and with a choice of Federal Army or SPAR door gunners….

I love those KM! All your VTOLs are awesome. That inducted fan VTOL has a great Command and Conquer (computer game) vibe to it, really cool.

That shuttle you have in the works is tops too. My favorite VTOL is still the Kestrel you did a limited run on, I should have bought more!

SPAR door gunners means the SPAR coming out soon?

I think part of the problem is what we see in pics posted here, that all of these ships seem to be designs based on Cobras, Apaches, Hinds and other current helicopter designs. My guess is that if you can do away with the rotor and use some other form of propulsion, the designs could be very different and even offer a great deal more flexibility. Think along the lines of the drop ships in Starship Troopers.

As far as fast roping is concerned, I'm thinking that by the time they can do all of this, they will also be able to outfit their special forces riders with some kind of rocket pack or gravity moderator pack so they can drop off as the ship flies over the drop zone.

You can put & use jet engines on VTOL aircraft Donier have done it see Donier 31 link
It used two pegasus (same as harrier) engines & some additional lift jet on wing tips.
Also EWR VJ 101 link though this a fighter.

You can solved most the problem about being blasted down by jet thrust by getting out the back door, as done on osprey & the Donier.

The problem with most sci-fi vtol designs are that the wings are either too short or engines too close to ground or both. There are some nice realistic

If you look as a high-bypass tubro-fan this have a tiny jet engine and big fan that provided most of the thrust. The jet part is small as they are very efficient for there weight so can have a big fan providing the thrust.
Can reduce thrust needed by designing craft to catch more the ground effect.
Would be able to reduce heat affecting troopers by direct thrust slightly outwards.

Replace the jet powered ducted fan with an electric motor powered ducted fan, electric motors are very power/weight efficient, if using petrol-chem fuel this would power hull mounted generators with power leads to wing fans.

Instead of powering down the fan use constant speed variable pitch blades, at zero pitch blades still spinning but little or no thrust.

Regards

MMG.

There is of course the option of using rocket motors rather than standard engines (like thrusters on spaceships but more powerful). That would negate the need for air intakes as the fuel will provide it's own oxygen for burning.

… but that still has the heat problem (unless, in the future, there are 'cold-burn' chemicals that don't actually burn but combine to create a reaction that has a cold output…).

Then you get the response that the nacelles are anti-grav or something similar. Does that mean the nacelles lift the vehicle by creating an opposing force of 20 or 40 tons or however much it weighs, underneath the craft. So standing under the vehicle will subject you to 20 tons of force pushing you down.

No more so than standing under a helicopter, though.

So no exiting the vehicle by rope, unless you like rappelling into a blast furnace.

"Yeah, man, but it's a dry heat!"
-Hudson

I've assumed that most directed thrust VTOLs are using turbofans. I'm not talking about military 3:1 bypass ratio engines where the fan might provide half the thrust of the engine (like Pegasus engines), I'm talking 10:1 bypass ratio or higher engines like modern airliners use where the core provides less than 20% of the total thrust.

Have you seen the engines on a 777? 10 foot diameter fan sections pushing 100,000lbs of thrust total, and the core (basically a B1's engine minus the afterburner) is making less than 20,000lbs thrust.

Jon, that ducted fan variant hits it right out of the ball park! Excellent.

Leland R. Erickson
Metal Express
metal-express.net

sci fi lifters??? love those dudes!!!

Haha… that just reinforces the idea that there is a picture on the internet for everything…

We're making those lifters actually.

We're making those lifters actually

Nice! The Greys have been working out! Steroids turn them green!

No, they're just very envious of human lifters….

The ducted fan lifters are fantastic. I will no doubt be adding to my pile of unpainted things!

Never let reality get in the way of cool.