TL9 Flying Chair

[Carlobrand]

A low cost alternative to the grav belt, designed with MegaTraveller.

TL9 Standard grav smallest unit is a 20 liter 40 kg Cr2000 unit drawing 100 kilowatts and delivering a ton of thrust. Too heavy for backpack, but you can build a chair model. Chair means rider outside, you need chassis only to contain the grav unit, power, and controls. A single electronic control unit draws 0.5 Kw, occupies 100 liters space, masses 5 kg, costs Cr70, provides half a control point, which should cover anything up to Cr5555 (less hull and presumably that seat unless it's one of those massaging models). Power consumption's ferocious, for what we're doing: you need 170 kg of TL9 batteries at a cost of Cr638 to provide an hour's power (higher tech batteries are lighter but pricier). However, with a ton of thrust available, your chair can get up to 800 kg and still fly you about nicely.

So -

Grav unit: 20 liters, 40 kg, Cr2000, 100 kilowatts
Eyeball avionics.
One seat: external, 20 kg, Cr100
Control unit: 100 liters, 5 kg, Cr70, 0.5 Kw,
Batteries, TL9: 609 liters, 609 kg, Cr2285*, providing power for 3.58 hours
Chassis (hull), TL9, factor 4, 750 liter: 26 kg, Cr1344 (if I got that right)
*per Consolidated MT Errata 2.2 adjusted prices

Total: 729 liters, 700 kg, Cr5799

At TL10, fuel cells become available. Fuel cells do require control units (!?) but there is ample control available to handle TL10 fuel cells delivering 110 Kw. These cost Cr2800 (a 90 Kw and a 20 Kw), consume 0.55 liters per hour, and occupy 130 liters - leaving 479 liters of the former battery compartment for fuel. Downside is if you want to go outside of atmosphere, you need to have both O2 and H2 tanks: gives you about 53 liters of H2 and 424 liters of O2, which is 96 hours flight time. Building it at TL10 with fuel cells costs Cr6314.

With a 100 kg payload (about a 150 pound man and 70 pounds of gear), the unit generates 1.2 G: 40 kph NOE, 240 kph top speed, 180 kph cruise speed, which is comparable with the better WW-I biplanes or some of the lower speed modern prop planes. It can carry up to 200 kg, managing 120 kph top speed and 90 kph cruise speed (about the speed of a car on the freeway); you could add a seat for a second passenger or panniers for additional cargo.

 

[BlackBat242]

Ha!

A REAL "Hoveround", anti-grav model!

 

[McPerth]

Nice design, just some comments:

Downside is if you want to go outside of atmosphere, you need to have both O2 and H2 tanks: gives you about 53 liters of H2 and 424 liters of O2, which is 96 hours flight time. Building it at TL10 with fuel cells costs Cr6314.

As the seat is external, you need oxigen for your passenger too, so I guess 96 hours of autonomy is quite an overkill...

With a 100 kg payload (about a 150 pound man and 70 pounds of gear), the unit generates 1.2 G: 40 kph NOE, 240 kph top speed, 180 kph cruise speed, which is comparable with the better WW-I biplanes or some of the lower speed modern prop planes. It can carry up to 200 kg, managing 120 kph top speed and 90 kph cruise speed (about the speed of a car on the freeway); you could add a seat for a second passenger or panniers for additional cargo.

According the definition of typical human in MT (IE, page 27), average weight is 100 kg, so I guess you must expect a higher payload (but in any case, at 120 kph top speed and 90 kph cruise speed, it's quite useful a gadget). In any case, good for you to take the passenger weight into the numbers, as MT rules forget about it.

All in all, a very nice design, quite comparable to my own designed grav bike shown here:
http://www.travellerrpg.com/CotI/Discuss/showpost.php?p=376972&postcount=30

And being lower TL, so, available earlier, it compares favorably to mine in this aspect.

 

[atpollard]

I love it.

 

[Carlobrand]

...As the seat is external, you need oxigen for your passenger too, so I guess 96 hours of autonomy is quite an overkill...

Well, yes, as with the grav belt it's the responsibility of the passenger to bring his own air, though I guess you could tweak it to provide some of that air to a passenger.

...According the definition of typical human in MT (IE, page 27), average weight is 100 kg, ...

Oh dear. According to IE, the average Imperial is 40 pounds overweight! (At least so far as the World Health Organization and those BMI's are concerned.)

Or maybe Vilani are stockier than Terrans. That never occurred to me before.

...All in all, a very nice design, quite comparable to my own designed grav bike shown here:
http://www.travellerrpg.com/CotI/Discuss/showpost.php?p=376972&postcount=30

And being lower TL, so, available earlier, it compares favorably to mine in this aspect.

I don't see anything in your design that needed TL13. Why didn't you make yours a TL10 thing?

 

[McPerth]

Well, yes, as with the grav belt it's the responsibility of the passenger to bring his own air, though I guess you could tweak it to provide some of that air to a passenger.

But then you'll have too much hydrogen, as the passenger(s) will only consume oxygen...

What I meant was that 96 hours autonomy seemed to me an overkill, as I guess no passenger will support so much time on it (and less so if he needs vacc suit). Assuming it's a civilian vehicle, thought for (moe or less) civilized áreas, where it can refill his fuel, I guess 6-8 hours will be enough, as the passenger will need to resta little after that (probably at a refueling station), as most people need when driving a car.

And if you need more, you can always use the cargo space for spare fuel (as many vehicles do today).

Oh dear. According to IE, the average Imperial is 40 pounds overweight! (At least so far as the World Health Organization and those BMI's are concerned.)

Or maybe Vilani are stockier than Terrans. That never occurred to me before.

That has been always my guessing on those numbers, that humans are stockier tan today. See, though, that people living in low gravity worlds (as ae most Traveller main planets) are likely to evolution just opposite to that...

I don't see anything in your design that needed TL13. Why didn't you make yours a TL10 thing?

The fuel cells. At TL 13 their output is 50% greater and the weight 75%, and (IIRC, it's long since I designed it) at lower TLs you needed 2 of them (and both being heavier). All in all, it would add about 200 kg to the design...

Seeing the difference in cargo capacity too, I guess your design would be the equivalent to a Smart, while mine to a bike (with the advantages and disadvantages both have).