Shuttle Speed

[LikeDaniel]

I know it would probably vary from series to series, but how long does it take for a shuttle to go from the Enterprise (holding in orbit above a planet) to the planet's surface?

I'm guessing an hour or two, but I don't really have any specific reason to believe I'm right. Anyone know?

 

[Timo]

Even the shuttlepod of ENT seemed to be able to do an orbit-to-surface run within what appears to be a rather short argument between Tucker and T'Pol in "Strange New World".

It's probably a matter of minutes (or dozens of minutes at most) rather than hours. Certainly it appears that way in VOY, where we witness some rapid reaction shuttlecraft work on occasion.

The distance would be something like 500-1000 kilometers in the usual case, probably - more or less straight down from a low orbit. The space part would probably be at several thousands of kilometers per hour, with multi-hundred-gee accelerations. The atmospheric flight could well be super- or hypersonic without creating massive sonic booms or friction glow if the futuristic forcefields of the shuttles cunningly manipulate the bow shock. They gotta do something to the atmosphere to enable these decidedly non-aerodynamic bodies to fly through it...

Preparation time would probably vary from show to show (newer shuttles might be able to deploy faster), and would also depend on the state of alert, which would probably directly translate to a state of shuttlecraft launch readiness.

Timo Saloniemi

 

[LikeDaniel]

Thanks, again, Timo!

My friends and I are doing a SciFi RPG and I just love what's availible here in Star Trek! So I'll probably be asking a lot more similar questions.

Hopefully before long I'll have watched through all the series (quite the task, btw (enjoyable, though!)) and will understand that universe much more in depth.

 

[Crazy Eddie]

For real-world spacecraft, from de-orbit burn to landing is usually on the order of 30 to 50 minutes. Most of that time is spent shedding excess momentum to atmospheric drag. If you're using braking thrusters to slow yourself down instead, you could probably reduce this to about 20 minutes, depending on the shuttle's thrust capabilities.

 

[scotpens]

What do shuttlecraft have in common with starships, subspace communications, and turbo-elevators?

They all move at the SPEED OF PLOT!

 

[Forbin]

I can't imagine it taking more than the 20 minutes Newtype figures.

 

[Gil T.Azell]

Some of the ones in NG were capable of warp 2-3.

 

[SWHouston]

There's probably more than one way to calculate this, but...
.25 is about 75,000 KPS. So if one uses Timo's 500-1000
kilometer orbit, it would have to be considerably less than that.

 

[Timo]

Getting to .25 lightspeed is probably a time-consuming process even for a large starship; the small shuttles may be incapable of achieving that speed within a short orbit-to-surface hop. FWIW, the runabouts of DS9 seem to go across the 1 AU distance between DS9 and Bajor at their closest in two hours (and the supposed 3 AU gulf at their most distant in six hours), so about 80 million kilometers per hour (which would include acceleration or deceleration), or about 20,000 kilometers per second on the average. Goes to show that impulse drive does allow for reasonably rapid acceleration to low relativistic speeds, but also that it isn't complete cakewalk (because the speed calculated above is not exceeded even in emergencies in DS9 - say, in "The Circle").

I sort of doubt the shuttles hit anything like 10,000 km/s when going from ship to surface, but they could well do hundreds or thousands of kilometers per second after minimal acceleration time and only have to slow down once entering the local atmosphere.

Timo Saloniemi

 

[Crazy Eddie]

There's probably more than one way to calculate this, but...
.25 is about 75,000 KPS. So if one uses Timo's 500-1000
kilometer orbit, it would have to be considerably less than that.

Indeed, at .25C it would take exactly 0.013 seconds to travel from an orbit of 1000km to a position on the ground. So if your intention is to hop on a shuttle craft and then slam it into the ground hard enough to shatter a small moon, you could definitely do it.

You would, of course, have to go much MUCH slower if your intention is to actually land on the planet, and slower still if you intend to survive the landing, and even slower still if you want to be able to take off again without putting most of the ship back together again.

 

[Forbin]

 

[MANT!]

http://www.projectrho.com/rocket/landing.php

 

[SWHouston]

Then...
All Space Craft have "Thrusters" (I think all ?)
I've herd of just "thrusters" like for station keeping, and
"Atmospheric" Thrusters (obviously for landing).
Unless I've mussed some technology somewhere,
one of these must be used.
Logic would conclude it would be Atmospheric, right ?

 

[Crazy Eddie]

Why would you need different thrusters for the atmosphere? The only functional difference in REAL space craft is the annoying fact that different engine designs have different specific impulses at various altitudes. If you're not worrying about a limited fuel supply (which, on Star Trek, few people do) then isp is a complete non-issue and you can use the same thruster in both cases.

 

[SWHouston]

You're probably quite right, but...
I only identify the "stated" differences, being...
Station Keeping, Maneuvering, and Atmospheric...
because each has been identified in script.
I suppose then, that "flowering" up the script,
is why their names change.

(sorry, forgot about Maneuvering earlier)

 

[Crazy Eddie]

You're probably quite right, but...
I only identify the "stated" differences, being...
Station Keeping, Maneuvering, and Atmospheric...
because each has been identified in script.

Those are functions, not names. You would BY DEFINITION use the same thrusters for maneuvering and station-keeping, which the writers of TMP obviously realized:

KIRK: Maneuvering thrusters.
SULU: Maneuvering thrusters...
KIRK: Hold stations.
SULU: Thrusters at station-keeping.

There's nothing to suggest they wouldn't use the same thrusters in an atmosphere either. Again, if they're not worried about specific impulse then a thruster is a thruster, all that matters is output.

 

[Timo]

The shuttles probably use gravity manipulation tricks to perform landings that create less downwash than today's helicopters. But some sort of rocketry is still apparently in use, as per dialogue, and gravitics haven't replaced Newtonian thrust altogether.

We know little beyond that. Dialogue doesn't dwell on the propulsive gravitics of the shuttles or the starships, but they are probably still there or else Newton would put a clamp on Trek-style spaceflight. Dialogue doesn't tell us what sort of rockets these thrusters are, either; they might not be rockets after all, but gravitic devices, but they do have the known quality of kicking up dust (see shuttles in modern CGI-rich movies or ST5) or manifesting as a bright jet when used in somewhat extreme conditions (see "Booby Trap").

Timo Saloniemi