Air\rafts

[magmagmag]

Gladius CP-20082 is a Broadsword-class mercenary cruiser owned by a small firm, ZEBJ Star Merc LIC, which operates a few other Broadsword-class ship as well as Protected Forces contingents across the Gristen sector.

Broadsword-class mercenary cruiser needs a utility vehicle of some sort to allow minor errands and surface excursions that do not call for a launch or cutter. The air/raft on the Broadsword class cruiser fills this requirement.

 

[atpollard]

I love the look of that Air/Raft, but that looks like a LOT of glass to take into “harms way”.

 

[kilemall]

I love the look of that Air/Raft, but that looks like a LOT of glass to take into “harms way”.

Transparent aluminum. This is the future.

 

[magmagmag]

Original model is

4-MAN HURRICANE AIR/RAFT from MT World Builder's Handbook

The air/raft is relatively ordinary in all respects, although it does carry a weapon mount allowing it to be armed if required. This model equips a missile launcher. The air/raft is capable of speeds up to 100 kph and can operate for long periods of time without refueling.

https://www.travellerrpg.com/index.php?threads/where-are-the-image-libraries.42276/

 

[atpollard]

Transparent aluminum. This is the future.

I would still prefer Superdense.

 

[whartung]

The air/raft is capable of speeds up to 100 kph and can operate for long periods of time without refueling.

As an aside, I am deep in the "air/rafts are too slow" camp, particularly an enclosed air/raft.

I routinely go over 120km/hr on my motorcycle, without a windshield (open top air/rafts have windshields, so do Miatas), though I do wear a helmet. I certainly observe others going even faster with little more than sunglasses.

An enclosed one should be able to easily do 200-300 kph.

 

[Spinward Flow]

As an aside, I am deep in the "air/rafts are too slow" camp, particularly an enclosed air/raft.

I agree.
The concept was quite obviously a "flying car" that performs no better than a ground car on a road ... but which gets blown around like a kite by the weather. It's barely a "pleasure boat in the sky" as originally detailed in LBB3.

One of the ways that I can justify the mediocre performance is pressing it into use as a (light) cargo crane for marshaling cargo loading/unloading in austere locations lacking ground support. If it's supposed to be used mainly for "ground support logistics" in austere conditions/locations then a high speed and enclosure isn't exactly needed.

However, if you want to take one out for spin on a road sky trip on an alien world, the air/raft really underperforms.
If you want to get somewhere QUICKLY and don't need to "load up the SUV" of an air/raft like a soccer mom, then what you really want is a Speeder ... the "sports car" of grav vehicles.

 

[Condottiere]

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

 

[Dragoner]

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

 

[mike wightman]

It's a 4 ton truck equivalent... four passengers and four thousand kilograms of cargo.

 

[Condottiere]

I'm partial to inflating the sides and floor.

Helium, for that extra lift.

 

[infojunky]

As an aside, I am deep in the "air/rafts are too slow" camp, particularly an enclosed air/raft.

I routinely go over 120km/hr on my motorcycle, without a windshield (open top air/rafts have windshields, so do Miatas), though I do wear a helmet. I certainly observe others going even faster with little more than sunglasses.

An enclosed one should be able to easily do 200-300 kph.

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.

 

[kilemall]

You’ve always got Striker or descendant version grav vehicle build sequences for air rafts more to taste. Most can be sped up.

Grav semis are a standard form factor IMTU. Think cab with a light utility passenger capacity and power coupled to a trailer sled where one slings on 2 5-ton or 10-ton container. Players wouldn’t routinely carry those except for starport D-E scenarios, otherwise the cargo gets dumped to quarantine/customs with final delivery by grav trucks tied to the planet.

 

[Grav_Moped]

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.

Yes, it's an automobile that flies -- an automobile from 1977, an era when the U.S. had a nationwide 55mph speed limit. I've operated vehicles with similar performance (ground vehicles, of course): a 1980 VW van with the old 67HP air-cooled 2.0L flat-four engine (70 mph top speed under the best conditions), and a 150cc motorscooter (rated top speed 59MPH, but minor aero tweaks can add a few MPH). This is what I see the Air/Raft and Grav Belt performance as being like.

Interestingly, the Speeder acts like a 2G Striker grav vehicle -- and it's still not supersonic! The thing that most people miss (and the game designers certainly did) is that for longer distances, you don't really need to go supersonic to hit high speeds in a grav vehicle. You just need to get above the atmosphere to avoid aerodynamic drag. Means you need to suit up for it, but maybe an hour of climbing gets you above the Karman line, and then your top speed is limited only by the planet's escape velocity.

Deceleration for re-entry could be aerobraked if the vehicle is so equipped and the driver is sufficiemy skilled, otherwise it's just doing the math from LBB2 with 0.1G...

 

[infojunky]

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.

Actually both Blimp and Helo models work. In terms of maneuverability and speed regimes. I use Helos because that is what I am most familiar with from experience. Note sideways maneuver is harder in Airships, but that could be rectified by more agile thruster placement.

Remember Blimps work by modifying their buoyancy then using their thrusters to maneuver. Often with limited ability for sideways maneuver

While Helos vector their lift for both lift and thrust. Allowing them to maneuver sideways.

Yes, it's an automobile that flies -- an automobile from 1977, an era when the U.S. had a nationwide 55mph speed limit.

This is another reason I use the Helo model, as low end models consider the Bell H-13 Sioux top speed around 130kph.

But, am going to stand where I started either model is fine. As both use relatively static lift and a bit of something else.

Interestingly, the Speeder acts like a 2G Striker grav vehicle -- and it's still not supersonic! The thing that most people miss (and the game designers certainly did) is that for longer distances, you don't really need to go supersonic to hit high speeds in a grav vehicle.

The correct term for the speeder is Transonic. Also note it is also just a little bit faster than a 747....

 

[Condottiere]

As I recall when I looked into it the expected alternatives, despite the two hundred thousand starbux price tag, the air/raft was a fairly attractive option.

However, if you creatively interpret the vehicle construction options in Mongoose, you can get a really cheap air/raft type vehicle.

I did seriously try to kickstart a zeppelin option - I think that might work more for a world without transport infrastructure.

 

[Grav_Moped]

The correct term for the speeder is Transonic. Also note it is also just a little bit faster than a 747....

Indeed. But one would think a nominal 2g thrust:weight ratio could do a little better than that. Maybe if it was actually streamlined for that aerodynamic regime instead of just looking fast? Lol

 

[Spinward Flow]

But one would think a nominal 2g thrust:weight ratio could do a little better than that.

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 = ?

 

[whulorigan]

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 = ?

Only for sufficiently large values of "2".

 

[infojunky]

Indeed. But one would think a nominal 2g thrust:weight ratio could do a little better than that. Maybe if it was actually streamlined for that aerodynamic regime instead of just looking fast? Lol

Sure throw down weird numbers for me to rabbit hole over... With good streamlining 1g will get you into that range. Note most supersonic Jet fighters have thrust to mass ration of around one... The SR-71 t/m ratio is only like 0.44 but that is a extreme fork, depending extreme streamlining and altitude.

The problem is that Traveller gives us a speed and a pseudo mass.

Then there is the question of the exact mechanism of gravity manipulation devices within the Traveller setting. Reading through the bulk of what has been written there are several different takes on how grav works.