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Old 09-30-2022, 02:06 AM   #1
hal
 
Join Date: Aug 2004
Location: Buffalo, New York
Default Vectored thrust vehicles of CP2020

Hi All,

Vectored thrust vehicles in Cyberpunk 2020, have long been a staple of CP2020. My question is simple enough:

Would it be accurate to say that AV-4 vehicles are like flying turtles? In other words, its thrust vector will always be from its bottom, with vectored thrust ducts able to redirect some of the thrust fighting Earth’s gravity being used to propel it forward. Problem is, if for any reason, the AV-4 is turned on its side, the AV-4, has no means to right itself to where its vectored thrust ducts can push against the gravity of earth. The only way to counter going “turtle” while in mid-air, is if it has vectored thrust ducts on all four of its sides.

Does this make sense?
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Old 09-30-2022, 02:33 AM   #2
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: Vectored thrust vehicles of CP2020

Do you have an image of the vehicle?
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Old 09-30-2022, 04:09 AM   #3
FrackingBiscuit
 
Join Date: Oct 2019
Default Re: Vectored thrust vehicles of CP2020

Quote:
Originally Posted by hal View Post
The only way to counter going “turtle” while in mid-air, is if it has vectored thrust ducts on all four of its sides.

Does this make sense?
I don't know what exactly you mean by "all four of its sides" - do you mean having duct on its top, bottom, and left and right sides?

That would be one way to survive flipping over, but it doesn't necessarily give it a way to right itself - depending on just how much its thrust can be vectored (as in pointed in a given direction), it might only manage to stay airborne while flipped over.

If I'm looking at the right vehicle on Ye Olde Google, the AV-4 looks like it's basically a van with the wheels replaced by downward-pointing lift engines. I don't know if actual forward thrust is provided by more fans in the back or if these lift engines have some way to vector their thrust a bit to provide forward propulsion - they don't actually look like they can move much. Some images look like they have vents that might be able to vector thrust upwards to a degree, so if it rolled over they might provide enough thrust to stay airborne or at least slow its descent to make a crash-landing possible, depending on the altitude.

That said, as a van with fans instead of wheels, it isn't really shaped like an air vehicle and looks like it's not supposed to get more than a few feet off the ground. In that case rolling over and losing lift is probably enough to cause an immediate crash no matter what kind of vectoring it has - it'd only take a split second to drop two feet and hit the ground. Not enough time to regain control. If it were an actual air vehicle, I would expect something like outboard pods housing the ducted fans that can actually rotate to provide thrust (like a V-22-style tilt-rotor, just with ducted fans instead of helicopter blades). If they could rotate enough such a VTOL aircraft could roll itself over pretty easily without needing to have a bunch of individual ducts pointing in every direction.
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Old 09-30-2022, 07:14 AM   #4
Varyon
 
Join Date: Jun 2013
Default Re: Vectored thrust vehicles of CP2020

When falling, it should be able to vector its thrust enough to put it in a spin, then stabilize once it's right-side up. This is much harder if it can only vector to go backwards and forwards, but I believe the AT-4 (or equivalent - this is 57 years later) in the introductory rescue mission in Cyberpunk 2077 demonstrates some side-to-side movement, and honestly you need that capability to be able to turn anyway, so I'd assume it can be vectored in any direction.

If already on the ground, it would depend on how strong the VERTOL system is as to if it can rock itself back and forth enough to flip over. Given the VERTOL is strong enough to counter gravity (and then some - these things can fly, not merely hover), then unless the vectoring is extremely weak (giving them a low top speed), I'd expect them to be able to rock back upright.

Quote:
Originally Posted by FrackingBiscuit View Post
That said, as a van with fans instead of wheels, it isn't really shaped like an air vehicle and looks like it's not supposed to get more than a few feet off the ground. In that case rolling over and losing lift is probably enough to cause an immediate crash no matter what kind of vectoring it has - it'd only take a split second to drop two feet and hit the ground. Not enough time to regain control. If it were an actual air vehicle, I would expect something like outboard pods housing the ducted fans that can actually rotate to provide thrust (like a V-22-style tilt-rotor, just with ducted fans instead of helicopter blades). If they could rotate enough such a VTOL aircraft could roll itself over pretty easily without needing to have a bunch of individual ducts pointing in every direction.
In that introductory mission I referenced, a Trauma Team AT-4 shows up near the top floor of a decently-tall building. Also, I believe the things are canonically used by Trauma Team to be able to reach pretty much anywhere in Night City, and there are some rather impressive skyscrapers there. I suspect the AT-4's ceiling is rather high. But, as I mentioned above, the game does take place 57 years after the time period hal is looking at, so the CP2020 versions of those vehicles may be stuck with a low operating ceiling. I kind of doubt it, however.
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Old 09-30-2022, 07:16 AM   #5
hal
 
Join Date: Aug 2004
Location: Buffalo, New York
Default Re: Vectored thrust vehicles of CP2020

Quote:
Originally Posted by Anthony View Post
Do you have an image of the vehicle?
Hi Anthony,
Here is a site that shows the original illustration for the AV-4 - a VTOL type vehicle.

https://cyberpunk.fandom.com/wiki/AV-4


The picture shows that this vehicle only has trust nozzles facing earthwards on the bottom of the vehicle. As a consequence, if it were to turn even a little so its thrusters were not perpendicular to the center of gravity, it could begin to descend. Yes, a computer fly by wire system Should keep it so that it compensates by thrusting harder on those nozzles that are closest to the side the AV-4 is going to topple, but at some point in time, if it does topple to its side, or be flipped upside down, it will crash regardless.

A jet that is using VTOL and slips sideways, can rely on the wings etc to right itself. If it is a winged configuration, the VTOL won't be its sole means of maneuvering. But if it lacks wings and lacks rudder and ailerons, it will quickly become a disaster.

CP2020 has these vehicles with an armor rating of up to 40 SP, where SP 1 is equal to 1 Inch of Steel armor. But frankly - it looks like a "let's make it cool" method of depicting an aircraft instead of trying for any semblence of realistic tradeoffs to make this thing fly.

This is why I'm trying to design the AV-4 as close to its operational specifications as possible yet not make this thing a 4 ton flying brick that can be easily overturned by an airburst attack that flips the AV-4 at an inopportune moment.
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Last edited by hal; 09-30-2022 at 08:16 AM.
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Old 09-30-2022, 07:28 AM   #6
hal
 
Join Date: Aug 2004
Location: Buffalo, New York
Default Re: Vectored thrust vehicles of CP2020

Quote:
Originally Posted by Varyon View Post
When falling, it should be able to vector its thrust enough to put it in a spin, then stabilize once it's right-side up. This is much harder if it can only vector to go backwards and forwards, but I believe the AT-4 (or equivalent - this is 57 years later) in the introductory rescue mission in Cyberpunk 2077 demonstrates some side-to-side movement, and honestly you need that capability to be able to turn anyway, so I'd assume it can be vectored in any direction.

If already on the ground, it would depend on how strong the VERTOL system is as to if it can rock itself back and forth enough to flip over. Given the VERTOL is strong enough to counter gravity (and then some - these things can fly, not merely hover), then unless the vectoring is extremely weak (giving them a low top speed), I'd expect them to be able to rock back upright.



In that introductory mission I referenced, a Trauma Team AT-4 shows up near the top floor of a decently-tall building. Also, I believe the things are canonically used by Trauma Team to be able to reach pretty much anywhere in Night City, and there are some rather impressive skyscrapers there. I suspect the AT-4's ceiling is rather high. But, as I mentioned above, the game does take place 57 years after the time period hal is looking at, so the CP2020 versions of those vehicles may be stuck with a low operating ceiling. I kind of doubt it, however.
On the basis that Night City has a population of 8 Million, and that it is in California - where tall skyscrapers tend to be not as Common as they are in Detroit or New York City - the idea was to take Los Angeles as a sample and see what the Operational aspects of the Trauma Team Inc would be like.

Oddly enough? L.A.'s footprint has a 40 mile by (I may be wrong in remembering) 25 mile region, the speed and range of the AV-4 CAN actually reach any location within LA within 6 minutes.

So, when I go about building the AV-4 using either of TL 8 or TL 9 materials from GURPS VEHICLE 2nd edition (for GURPS 3e), I'm hoping that I can build an analog for it, and that it will be reasonably close to the stats.

Cockpit volume is dependent upon:
Number of crew (1 or 2)
Number of Passengers (6)
Amount of cargo carrying capacity (about 1.43 Tons or roughly 60 to 110 cubic feet of cargo capacity

It will have two turrets, some military avionics, etc.

My only real concern is how stable it is in flight, and whether or not it can be easily made or allowed (due to pilot error) to turn sideways and and begin fall out of the sky.

Now, let's say hypothetically speaking, you've got an AV-4 flying at say, 8,000 feet. It flips. How far will it fall before it can potentially spin, then at the right moment, counter spin and right itself? Can a pilot be able to handle this task or will it require a program to instigate the righting on its own?

Just taking a good HARD look at my design options before I start.

Now if it were me? I'd likely set it up for 8 nozzles. Four primary ones for the primary thrust against gravity (bottom of vehicle) and four secondary ones at the top. This way, if you require a "Spin" the two right side bottom nozzles thrust at full power, and the two left TOP nozzles fire at full power and the whole beast spins rapidly. If you're stuck with only four on the bottom, that seems like a recipe for problems.

Just thinking about this before I even try to build a GURPS Analog for it.

:)
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Old 09-30-2022, 07:33 AM   #7
Aldric
 
Join Date: Nov 2015
Default Re: Vectored thrust vehicles of CP2020

Can't see a picture from your link :D

But a quick search online gives plenty of pictures, and they do look like vans with wheels replaced by ducts.

They're suppsed to be armored (and armed) weight 8600 lbs fully loaded and fly at 350 mph (top speed I guess).
They're also meant to fly just about everywhere in the city, from the top of the tallest skyscrapers to the bottom of the lowest alleys.
So definitely not turtles at least as far as speed is concerned.
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Old 09-30-2022, 08:16 AM   #8
hal
 
Join Date: Aug 2004
Location: Buffalo, New York
Default Re: Vectored thrust vehicles of CP2020

Quote:
Originally Posted by Aldric View Post
Can't see a picture from your link :D

But a quick search online gives plenty of pictures, and they do look like vans with wheels replaced by ducts.

They're suppsed to be armored (and armed) weight 8600 lbs fully loaded and fly at 350 mph (top speed I guess).
They're also meant to fly just about everywhere in the city, from the top of the tallest skyscrapers to the bottom of the lowest alleys.
So definitely not turtles at least as far as speed is concerned.
fixed link - sorry
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Old 09-30-2022, 09:15 AM   #9
mburr0003
 
Join Date: Jun 2022
Default Re: Vectored thrust vehicles of CP2020

Quote:
Originally Posted by hal View Post
Does this make sense?
I always redesign my V-TOLs in cp games, since the artists aren't aeronautics engineers and clearly have no idea how those machines would abysmally fail.

I simply design wider bodied, stubbier winged, harriers...

Though I've also gotten into quad-rotor concepts of late. They don't move as fast, but for routine travel city-hoppers, they work great.
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Old 09-30-2022, 10:25 AM   #10
Fred Brackin
 
Join Date: Aug 2007
Default Re: Vectored thrust vehicles of CP2020

Quote:
Originally Posted by hal View Post
Hi All,

Vectored thrust vehicles in Cyberpunk 2020, have long been a staple of CP2020. My question is simple enough:


Does this make sense?
There have been attempts to build VTOLs such as you describe and they are at least as vulnerable to "turning turtle" as you think.

To look at what is by far the most succesful VTOL you go to the Harrier and the Harrier has a 3-dimensional system of compressed air jets ("puffers"). These give a very positive directional control in all directions and good safety.

So assume that your AV-4s are designed by competent engineers and have puffers hidden in their bodywork. Vectoring thrust in 2 dimensions isn't going to be good enough..Not enough directional control and much of the time too much thrust for jsut controlling attitude.
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