Author Topic: angle of attack (first chapter)  (Read 6183 times)

Offline knnn

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angle of attack (first chapter)
« on: October 08, 2015, 01:02:11 AM »
Rereading the first chapter...

Basically, they consider using a "steeper angle of descent", because "gravity will get us there faster".  Obviously this cannot be strictly correct, but I was thinking maybe this meant that the ship itself was angled downward, creating a smaller cross-section for wind resistance. 

Thing is, I couldn't find a reference for an angle downward.  The ship simply falls "like a rock" and is still moving forward from the ethereal web.  That's what creates the angle of attack.  If this is so, they can obviously decide how much forward motion they have, but I don't see how they can drop faster. 


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Offline Shecky

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Re: angle of attack (first chapter)
« Reply #1 on: October 08, 2015, 02:30:40 AM »
Easy. Turn down the power to the lift crystal and let gravity do the rest. Everything else requires power and/or sailing of one kind of the other.
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Offline knnn

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Re: angle of attack (first chapter)
« Reply #2 on: October 08, 2015, 02:35:15 AM »
Easy. Turn down the power to the lift crystal and let gravity do the rest. Everything else requires power and/or sailing of one kind of the other.

You're saying that initially the plan was not to turn off the lift crystal at all?  I thought that's exactly what a power dive was -- turn off the lift crystal and then turn it back on when you reach the proper altitude? 
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Offline Second Aristh

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Re: angle of attack (first chapter)
« Reply #3 on: October 08, 2015, 03:44:35 AM »
You're saying that initially the plan was not to turn off the lift crystal at all?  I thought that's exactly what a power dive was -- turn off the lift crystal and then turn it back on when you reach the proper altitude? 
Power dive would imply that there's something more than gravity helping.  Grimm always called them attack dives or combat dives from what I can tell.

I don't think the ship was angled down for the dive just because of the extra complexity for aiming the cannons.  But it might not be totally impossible for the steeper dive to be the fastest approach for the ship.  Moving forward means interacting with etheric currrents, which screams drag to me.  So, less forward motion would translate to less drag and possibly more speed.  That's just my amateur physics intuition.  I haven't considered things like inertia.
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Offline knnn

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Re: angle of attack (first chapter)
« Reply #4 on: October 08, 2015, 12:12:23 PM »
Power dive would imply that there's something more than gravity helping.  Grimm always called them attack dives or combat dives from what I can tell.

But then that quote about gravity doesn't quite work.

But it might not be totally impossible for the steeper dive to be the fastest approach for the ship.  Moving forward means interacting with etheric currrents, which screams drag to me.

Ah, you're saying that the web acts as a kind of sail and would serve to increase drag.  That might fit.
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Offline Second Aristh

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Re: angle of attack (first chapter)
« Reply #5 on: October 08, 2015, 07:02:55 PM »
But then that quote about gravity doesn't quite work.

Ah, you're saying that the web acts as a kind of sail and would serve to increase drag.  That might fit.
Huh?  Which gravity quote are you referring to?

But yeah overall my current theory is that the webbing acts as a sail that catches etheric currents when it is charged.  Controlling the charge controls steering for the ship since you could affect which sails get pushed.  Those kind of control options make sense to me why mundane sails got dropped in the majority of ships.  The lift crystal provides the vast majority of keeping the ship in the air while the trim crystals are smaller versions to keep the ship stable and upright from winds/shifting weight/etc.
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Offline knnn

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Re: angle of attack (first chapter)
« Reply #6 on: October 08, 2015, 07:15:45 PM »
Huh?  Which gravity quote are you referring to?

The engineer says something along the lines of "gravity will get us there faster".  This doesn't quite make sense if they were planning on turning off the lift crystal from the start.
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Offline Second Aristh

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Re: angle of attack (first chapter)
« Reply #7 on: October 08, 2015, 07:28:37 PM »
The engineer says something along the lines of "gravity will get us there faster".  This doesn't quite make sense if they were planning on turning off the lift crystal from the start.
I don't understand the inconsistency.  Using gravity to accelerate would be faster than sailing horizontally in normal circumstances.  To use gravity like that, you basically turn off the lift crystal.
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Offline knnn

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Re: angle of attack (first chapter)
« Reply #8 on: October 08, 2015, 07:44:11 PM »
I don't understand the inconsistency.  Using gravity to accelerate would be faster than sailing horizontally in normal circumstances.  To use gravity like that, you basically turn off the lift crystal.

But they were always going to do a dive.  Doesn't this mean they were always going to turn off the crystal and use gravity? 
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Offline Second Aristh

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Re: angle of attack (first chapter)
« Reply #9 on: October 08, 2015, 07:50:15 PM »
But they were always going to do a dive.  Doesn't this mean they were always going to turn off the crystal and use gravity?
yeah...

I still don't follow you though.
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Offline knnn

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Re: angle of attack (first chapter)
« Reply #10 on: October 08, 2015, 07:52:56 PM »
yeah...

I still don't follow you though.

Ok, so if they were going to turn off the crystal, then the downward movement was always going to be due to gravity.
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Offline Second Aristh

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Re: angle of attack (first chapter)
« Reply #11 on: October 08, 2015, 08:08:00 PM »
Ok, so if they were going to turn off the crystal, then the downward movement was always going to be due to gravity.
Exactly.  A free fall versus a power dive.
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Offline knnn

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Re: angle of attack (first chapter)
« Reply #12 on: October 08, 2015, 08:18:11 PM »
Exactly.  A free fall versus a power dive.

So isn't it "the webs will pull us down faster" and not "gravity will get us down faster"?
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Offline Second Aristh

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Re: angle of attack (first chapter)
« Reply #13 on: October 08, 2015, 08:25:43 PM »
So isn't it "the webs will pull us down faster" and not "gravity will get us down faster"?
Not necessarily.  The webbing has to catch etheric currents to move the ship in the first place.  But, if the ship is going faster than the currents (by free falling), then you have more drag.  Turn off that drag altogether by not charging the webbing, and you get to go faster than you would using the webbing.  It works more like a sail than a jet engine.
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Offline raidem

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Re: angle of attack (first chapter)
« Reply #14 on: October 08, 2015, 10:36:18 PM »
Yeah, my jist i take away mostly is forces down is mostly a function of gravity, the crystals are there to act against this force.  Sometimes, particularly during dives, it useful to lessen the lift of the lift crystal, then when you need to arrest your descent you increase the lift of that crystal.
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