Air\rafts

[infojunky]

It can ... when the local gravity is lower than 1G ...
When the local gravity is higher than 1G, the Speeder only has enough thrust capacity for subsonic flight.

Because 2-1 = ?

That depends on your understand of how grav works....

 

[Vargr Breath]

It can ... when the local gravity is lower than 1G ...
When the local gravity is higher than 1G, the Speeder only has enough thrust capacity for subsonic flight.

Because 2-1 = ?

If I knew there was going to be a test, I would have studied for it.

 

[infojunky]

If I knew there was going to be a test, I would have studied for it.

Honestly I think the discussion of Grav Vehicles and their nature should be it's own thread.

 

[atpollard]

Honestly I think the discussion of Grav Vehicles and their nature should be it's own thread.

Done.

 

[whulorigan]

There are probably different grav motor/air/carriages with different performances.

The original in Dumarest sounded like a flying zodiac, though Traveller's sounds more like a 1 ton truck.

Honestly I trend to compare Air/rafts to Helos, as such there is a wide range of performance. Heck Book3 gives examples of either end of that spectrum... Consider the Speeder.

. . . Conceptually, it's not a helicopter without the spinny things, it's a blimp without the balloon -- you can't tilt it sideways to go faster. This is not compatible with the products of Striker or subsequent design systems though.

Yes, it's an automobile that flies . . . This is what I see the Air/Raft and Grav Belt performance as being like.

Recall that the flavor text from CT mentions that the slang terms for them are "Floater" and "Flyer". Those two terms by themselves suggest at least two different performance regimes.

• The "Floater" suggests to me the more standard Air/Raft as inspired by the Dumarest novels, which is (as its name implies) essentially a floating Raft for moving things and/or people from place to place at slow speed and heavily influenced by wind effects (if any). It is not really intended for long distance transport, but more for moving things about a local region.
• The "Flyer" designation suggests to me a faster vehicle (open or closed) meant for potential longer-range transport, more of an Air/Car or Grav/Car, but otherwise lumped in with the Air/Raft for general description purposes in the Equipment Section text.

 

[Timerover51]

I guess that I view Air Rafts as the Traveller equivalent of the passenger pick-up truck. Capable of carrying a small number of people along with some cargo.

 

[infojunky]

Done.

And then I went and started that tread.... Mea Culpa....

 

[Grav_Moped]

I guess that I view Air Rafts as the Traveller equivalent of the passenger pick-up truck. Capable of carrying a small number of people along with some cargo.

VW Transoprter Type 2 (T3).

... but with a sunroof, since they're supposed to be open-topped.

Or the double-cab pickup version.

Only slightly larger.

 

[AnotherDilbert]

Only slightly larger.

It's a four tonne vehicle with a four tonne payload capacity, it's more than slightly larger than a light van...

More like a four-tonne truck:

Terrängbil 30 (Scania SBA 111)


Yeah, not as cute...

 

[AnotherDilbert]

I've discussed this on other threads, but IMTU the nominal Air/Raft's capabilities are "counteract local gravity, plus 0.1G thrust in any direction" (basically, as described in LBB3). Conceptually, it's not a helicopter without the spinny things, it's a blimp without the balloon -- you can't tilt it sideways to go faster. This is not compatible with the products of Striker or subsequent design systems though.

When you say "plus 0.1G thrust in any direction" you are using Striker...

The LBB3 description if very brief, it does not discuss performance with different loads or gravities at all, just like all other vehicles.

The function is described in Striker basically as:

Striker, B3, p8:
__ K. Grav Generators: A grav vehicle requires grav generators installed in its chassis. Each .02 m³ of grav generators produces 1 ton of thrust and requires .1 megawatts of power from the power plant. They weigh 2 tons and cost Cr100,000 per m³.

It's just thrust, like a helicopter.


Of course, TNE had different ideas...

 

[Condottiere]

You always have to bear in mind the price tag.

It's not the family jalopy.

 

[coliver988]

You always have to bear in mind the price tag.

It's not the family jalopy.

this is an important aspect to me. If they wanted the air/raft to be ubiquitous then it should have been a lot cheaper. You can get a dozen ground vehicles for the same price pretty much. Though having the ability to fly is good but not always necessary.

Why most of my ports use ground vehicles for a lot of mundane things: a lot cheaper. And drivers only have to worry about 2D piloting vs 3D (and we all know how crazy everyone else drives!) But: there is always a place for grav vehicles as it is a SF universe and by golly I want my flying car!

Back to performance: I always figured the helo model as well but never dove into the details. It flies, does not create a backwash, and can reach orbit in planet size hours.

 

[Spinward Flow]

Why most of my ports use ground vehicles for a lot of mundane things: a lot cheaper. And drivers only have to worry about 2D piloting vs 3D (and we all know how crazy everyone else drives!) But: there is always a place for grav vehicles as it is a SF universe and by golly I want my flying car!

LBB3.81, p21 and TTB, p112:

Most ground cars require a driver, although at higher tech levels the car will steer itself (and on highly civilized worlds driving under human control is illegal in cities).

Autonomous (self-driving) vehicles certainly seems to be a TL=8 compute solution. When interstellar travel is commonplace, it's actually trivial to assume that TL=8+ vehicles (wheeled, tracked or gravitic) will have autonomous driving capabilities. Fun thing is that you can then bring Law Level into the picture as a "roll lower than Law Level on 2D" for manual driving operation to be street legal on TL=8+ worlds if you want.

Extending that even further, you can then extrapolate that 3D movement needs to make the same "roll lower than Law Level on 2D" throw TWICE (so basically "rolling at disadvantage") for gravitic vehicles to be manual operation legal. In other words, under "most" circumstances, all gravitic vehicles are self-piloting under computer control, with manual override control as a backup option rather than as a primary crew role in order to move the gravitic vehicle at all. So instead of a "grav pilot" you're mostly dealing with a case of "grav navigator" instead, with the computer doing most of the work of flying for you (fly by code) for safety+legal reasons.

Now, vehicle piloting skills will still be necessary for any kind of adversarial vehicle maneuvering (race driving, paramilitary, military, austere conditions, low tech, etc.) conditions that don't fall into the "routine daily civilian" stuff ... but you get the idea.



Also, shout out to Full Self Driving being a thing over 40 years ago!

 

[mike wightman]

Only problem is you would need a car trailer for the computer...

 

[Condottiere]

There will always be scooter subcultures.

 

[whulorigan]

Only problem is you would need a car trailer for the computer...

 

[kilemall]

I’m under the impression that MgT air/rafts are quite a bit cheaper then CT- correct?

 

[whulorigan]

I’m under the impression that MgT air/rafts are quite a bit cheaper then CT- correct?

I don't recall off the top of my head and don't have the books in front of me at the moment, but IIRC the price of Air/Rafts were an errata item in CT as well, and came down by about an order of magnitude if memory serves.

 

[kilemall]

I don't recall off the top of my head and don't have the books in front of me at the moment, but IIRC the price of Air/Rafts were an errata item in CT as well, and came down by about an order of magnitude if memory serves.

That was from MCr6 to Cr600000. Which still makes it ship/gov/service/corps/rich sentient territory.

MgT I don’t remember but my ghost impression was in the Cr100000s- still not cheap ground prices but more upperclass accessible.

 

[Dragoner]

In mgt2 it is Cr250,000