[HPforGrownups] Re: Flight to London - Speed Questioned

[Random]

No: HPFGUIDX 72013


On Sunday, Jul 20, 2003, at 17:33 America/Indianapolis, Steve wrote:

> --- In HPforGrownups at yahoogroups.com, Random <random832 at r...> wrote:
>>
>> On Saturday, Jul 19, 2003, at 21:51 America/Indianapolis, Steve wrote:
>>
>>> bboy_mn:
>>>
>>> I'm sure I mentioned windchill and wind turbulence. .... Wind
>>> turbulence at 500mph would rip your head off. ...
>
>> Random replies:
>>
>> Well, why can't _that_ be the magic bit? It's going 500mph _for
>> real_  but maintains a bubble of static air around it.
>>
>
> bboy_mn:
> First, as someone has already pointed out, the book specifically
> mentions windchill and wind turbulence, and not just wind over the
> windshield turbulence.

We're not told the nature of the turbulence, so i'd like to know how 
you make this judgement. it could very well be (analogously, by 
exceeding the capabilities of the bubble just slightly and thereby 
"leaking through") precisely that.

> Harry and everyone else had to lay low against
> the body of the Thestrals to avoid the slipstream (another word for
> air turbulence). If there was anything blocking them from the wind, it
> was the Thestral's head and neck, and at 500mph, that wouldn't be 
> enough.
>
> Second, if you are going to insist on real-time flight then it would
> seem logical to insist on real-time flight physics. There is a reason
> why no propeller driven plane ever exceeded the speed of sound. No
> matter how streamlined the body or how powerful the engines, the
> propellers themselves created enough of an aerodynamic barrier to
> prevent the plane achieving those speeds. So a static bubble would
> screw up the aerodynamic; it would create such a large wind resistant
> barrier that it would prevent near sound speeds.

Can you find me a reference on this? I think it's likely a bit 
different from what you described and SPECIFIC TO THE FACT THAT IT'S 
PROPELLERS. that is, very specifically dependent on the fact that it's 
blades turning perpendicular to the direction of flight.

Keep in mind that a real airplane like, say, a 767, _does_ have a 
static air bubble - with an aluminum skin around it.

Also, if we take the speed to be 500mph, it is not "near sound speed", 
as the speed of sound is closer to 800mph.

>
> Next, as long as we are on the topic of aerodynamics, the only way the
> Thestrals would be able to fly is if its wings were outside the static
> bubble. No airflow means no lift, with no thrust or lift, the Thestral
> couldn't fly.

Or we could say the wings are decorative and the flight is entirely 
magic-powered.


For an even simpler explanation than the bubble - maybe the wind was 
behind them... the magic could be as simple as that - create a tailwind 
jetstream going forward in the direction of flight at 450mph, and then 
fly at 500mph within it, thus the ground speed _really is_ 500mph, and 
at the same time the airspeed _really is_ 50mph.

you have to keep an open mind.. .just because you thought of the 
slow-motion-apparating thing and it's your pet theory doesn't mean all 
other theories don't deserve a chance

> bboy_mn:
> You forgot what it's like to travel by Floo powder. There is a
> sensation of physically moving through space, and a sense of real-time
> experience to the 'Flooer' (Flooer - one who Floos). You see yourself
> moving through the Floo Network, you see fireplaces wizzing by, you
> have some sense of moving through physical time and space, even if the
> exact time and space are warped by magic. In addition, there is a
> deafening 'roaring' sound and the sensation of cold ... slapping your
> face. I can't say for sure if that is wind turbulence and wind chill,
> but I suspect it's related.

well, given the description you refreshed my memory of, it seems rather 
more like space-folding than anything else. i.e. the distance he covers 
is much shorter than the outside-world distance between the endpoints.

> bboy_mn:
> No not teleportation again because you experience the sensation of
> physically moving through time and space. Again, the sense of time and
> space are not proportional to the distance traveled, but you do still
> sense time and movement throught space. Floo and Portkey transport
> you, the don't Teleport you.

And you know how teleportation feels, do you?? it could be 
teleportation accomplished by space-folding.