Factual mistakes in shows and books

I actually have a couple of examples for you:

1) The hand lasers in "The Black Hole." While the beams are clearly visible (annoyingly) there isn't any sort of propagation delay, so all the gun fights look like an incredibly violent round of laser tag (all the more so because the interior sets of USS Cygnus look a lot like a giant laser tag arena).

2) Most of the beam weapons in Babylon 5. While not actually lasers, there's no propagation delay as long as they're firing in beams. Pulses move slower, and I'm not really sure why that is.

3) All of the laser weapons in Ben Bova's "Asteroid Wars" novels, from Lars Fuchs' modified mining laser to the big purpose-built antiship weapons used by the mercenaries. It's harder science fiction than usual, but here again there's the implication that the first clue you have that someone is shooting at you is usually when a big chunk of your ship falls off. And something similar in "The Expanse" when the belters start weaponizing the communication lasers of some of their ships.

 

I've read most of the books in Bova's Grand Tour series 2-3 times - the Asteroid Wars novels are a subseries of the overall series, as Lars Fuchs is a major character in Venus - and I never really noticed this.

I'll have to read those novels again and pay more attention this time.

 

There's this awesome moment in "The Rock Rats" when Lars' ship is getting fired on for the very first time. They have NO IDEA what's going on until suddenly his screen flickers out and he's like "Huh... weird... Why is the antenna not working? Diagnostic says it just got disconnected... Wait, did that guy just laser my antenna? Holy shit, that guy just lasered my antenna!"

Paraphrasing, of course

 

Of course. Lars Fuchs may have gradually changed from a mild-mannered university student to miner/entrepreneur to terrorist, but he would never use such crude language.

 

You mean the PPGs? Those aren't beams. They fire superheated bits of plasma surrounded by a magnetic field, which dissipates when striking the target.

 

That's not EXACTLY what I mean, since in many cases we see beams and pulses being fired from the same weapon emplacement.

Though, in fairness, this is another symptom of the ship's designers and the VFX team not being on the same page or anywhere close to it, as I understand that the Omega's designers actually designated specific features on the ship where pulse weapons were supposed to come from and the FX people ignored them and stuck em on wherever they felt like it. Incidentally, the same thing happened with the fighter bays: the Starfuries were supposed to drop out of the bottoms of the rotating sections on the Omegas, EXACTLY like they do from Babylon-5's "cobra bays."

 

By "PPGs" I was only referring to the hand-carried Phased Plasma Guns.

 

Actually, I'm glad they didn't do that. The Cobra Bays are cool looking, but physics don't work that way in real life.

The velocity of the Starfury at launch would be equal to the station's tangential velocity at that radius. After detaching, it would appear to the Starfury pilot that the station rotates up and away from them. Honestly, I would *love* to see someone do a full CGI animation of an accurate Starfury launch.

 

Bothers me how there's no explanation for how Joel eats or breathes in MST3K. Then again, it's just a show and I should really just relax.

Serious answer though, I'm a birder and it always makes me laugh when I see Bald Eagles in movies and shows with Red-tailed Hawk calls dubbed over them, because Bald Eagle calls sound a little ridiculous (The Colbert Report did this). Or you'll hear Common Loon calls in wilderness scenes in locations where Loons would never occur. Stuff like that.

 

To be fair, that makes a lot more sense with a show like The Colbert Report, which deliberately values "truthiness" over accuracy.

(Still love that photobombing hawk in that one Next Genertion epsode. I think it was Who Watches the Watchers.)

 

I think there are only three bird sounds in all Movies and TV.

 

LMAO yep, pretty much!

Red-tailed hawk for all raptors.
Common Loon for wilderness scenes.
Mourning Dove for all owls.

 

I think the red tail hawk gets used for things like Pterosaurs, too.

 

And the laughing kookaburra in every jungle movie. Doesn't matter whether the jungle's supposed to be in Africa, Asia or South America -- we always hear that damned Australian bird!

 

I don't think that this is accurate either. Yes, the starfury is going to gain some tangental velocity as it releases, but it IS going to have an outward component from the axis of rotation. Your drawing basically ignores centrifugal force altogether and drastically overstates the coriolis effect for a large rotating system.

 

Type one diabetes is a condition that programmes don't get right very often.

 

No, there won't be any outward component. The instant the Starfury releases, the outward force is now zero (there are zero forces at all at this point), and it continues in a straight line along the velocity vector, which is tangent to its previously circular motion. Saw this exact experiment demonstrated on Mr Wizard way back in the day, plus I have the physics background now to back it up.

 

Speaking as a guy who has to deal with this exact sort of movement LITERALLY every day of my life, this is definitely not the case. Again, you're factoring centrifugal force at the moment of release completely out of the equation. Even if the ship INSTANTLY released from the rotating system, there is still an "outward" vector component imparted from the surface it releases from; this component is usually very small, but it's proportional to the amount of time it takes for the object's "hook"' or whatever it's holding on to to actually detach. That time component is always greater than zero. And I get paid a really impressive amount of money teaching teenagers how to maximize that time component in order to perform release moves on an uneven bar without killing themselves.

For star furies, that component is SIGNIFICANTLY greater than zero, as their launch system is a rotating leaver 5 to 7 meters long. With a centrifugal force of, say, 3m/s^2 at launch, it'll leave that launch arm with anything between 10 and 15m/s velocity before it even leaves the bay (depends on the friction force of the leaver and whether or not it is fitted with some sort of piston/ram or catapult thing).

So tangental velocity will be equal to the system's rotational velocity, PLUS the vector imparted by the "falling" of the object in the time before release. That time component, again, is always greater than zero, so even in your Mister Wizard experiment the radial component is small enough to ignore but it is not actually zero.

ETA: it gets even more complicated when you consider the size of the object itself from a release point. If, for example, you were pushing a 30 foot truck off a cliff that opens into space (from the bottom of, say, Brown Sector where it's about 1G), then the front end of the truck is going to drop while the back end is still moving forward. That's a much more complicated equation, since there's a tipping moment and a rotational component to the truck's motion that depends on where exactly it's center of mass is and how quickly it goes over the cliff. Either way, the downward vector imparted by the tumbling truck is equivalent to the truck falling in full gravity right up until the moment it goes over the edge.

Off the top of my head (been a long time since I had to do this on paper) I believe the "cheat" is that the tangental vector is equivalent to the INITIAL release point and not the point where the object finally separates. So if it takes 3 seconds to fully release from a system rotating at 15 deg/sec, then the actual vector would be a tangent from 45 degrees before the release point.

 

Okay @Crazy Eddie, I don't disagree with that. I was thinking more along the lines of ideal point systems with an instantaneous release. And with the Starfury, you'd want to redesign that launch cradle to be more analogous to a bomb release from an aircraft instead of having that big arm rotating in order to reduce any unwanted forces. But I believe my initial point is still valid, in that the Starfury (with a redesigned launch system) should be going (approximately) tangentially to its original circular path instead of perpendicular to it.

 

Why would you WANT it to release tangentially? It actually appears the whole point of the rotating release system is to PREVENT exactly that sort of thing from happening. Instantaneous release isn't something that happens in the real world no matter what kind of system you have, so a system that accounts for that and removes the variability of the release point would be alot safer.

Put another way: you don't want to be in a situation where a stuck docking clamp or some other less-than-perfect separation can result in your fighter tumbling into the side of the hangar deck, or a situation where the orientation of the fighter is not strictly controlled as it releases (it begins to tumble rather than drop straight down). Having it slide vertically out of the bay means fewer things can actually go wrong with the launch, and even when they DO, the fighter is already out of the bay by the time they happen.

Again, it's a disconnect between the "ideal" mathematical models and what ACTUALLY HAPPENS in reality. Even under the best circumstances you can imagine, the final vector will never actually be completely tangental to the axis of rotation, so you're just better off factoring that extra vector into your designs and using it as a safety margin.