A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Piloting
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Lancair crash at SnF



 
 
Thread Tools Display Modes
  #1  
Old April 25th 08, 11:36 AM posted to rec.aviation.piloting,rec.aviation.student
WingFlaps
external usenet poster
 
Posts: 621
Default Lancair crash at SnF

On Apr 25, 8:31*pm, Stefan wrote:
WingFlaps schrieb:

Try reading the statement again, here it is:
"Now we add in the energy losses from having to accelerate with the
wind and to glide speed."

To summarise your missed point, the pilot control inputs cost energy
that is not factored into simple glide/time analysis.


This is absolutely correct. But then, I dont understand the connection
to your first statement regarding the wind. Additioinal drag by control
input is completely unrelated to the presence or non-presence of wind.


Itls a turn upwind to downwind. That involves 2 direction changes, one
to reverse course and the the other to line up the runway. If there's
wind there will be an effect on line up. Try thinking about more
factors that cost altitude OK?

Cheers
  #2  
Old April 25th 08, 11:45 AM posted to rec.aviation.piloting,rec.aviation.student
Stefan
external usenet poster
 
Posts: 578
Default Lancair crash at SnF

WingFlaps schrieb:

Itls a turn upwind to downwind. That involves 2 direction changes, one
to reverse course and the the other to line up the runway. If there's
wind there will be an effect on line up. Try thinking about more
factors that cost altitude OK?


All good and fine, and I'm thinking about a lot of factors, btw. also
about human ones which are usually the weak link, but you still have not
explained what you meant when you wrote: "Now we add in the energy
losses from having to accelerate with the wind."
  #3  
Old April 25th 08, 12:01 PM posted to rec.aviation.piloting,rec.aviation.student
WingFlaps
external usenet poster
 
Posts: 621
Default Lancair crash at SnF

On Apr 25, 10:45*pm, Stefan wrote:
WingFlaps schrieb:

Itls a turn upwind to downwind. That involves 2 direction changes, one
to reverse course and the the other to line up the runway. If there's
wind there will be an effect on line up. Try thinking about more
factors that cost altitude OK?


All good and fine, and I'm thinking about a lot of factors, btw. also
about human ones which are usually the weak link, but you still have not
explained what you meant when you wrote: "Now we add in the energy
losses from having to accelerate with the wind."


Yes, I did. I'll explain it one last time. A direction change in a
plane is always due to acceleration (and that means more drag). That's
Newtonian physics. You go from up wind direction (takeoff is usually
up wind) to turn in the wind direction to land down wind. There's an
acceleration, it is a change in _velocity_ it creates drag, it costs
height and that's the important bit. Now do you understand -TURNS are
not free, they cost more height than the distance covered. Get it
now?

Cheers
  #4  
Old April 25th 08, 12:19 PM posted to rec.aviation.piloting,rec.aviation.student
Dylan Smith
external usenet poster
 
Posts: 530
Default Lancair crash at SnF

On 2008-04-25, WingFlaps wrote:
On Apr 25, 10:45*pm, Stefan wrote:
WingFlaps schrieb:
explained what you meant when you wrote: "Now we add in the energy
losses from having to accelerate with the wind."


Yes, I did. I'll explain it one last time. A direction change in a
plane is always due to acceleration (and that means more drag).


But that's got nothing to do with "having to accelerate with the wind",
that's merely the energy cost of making the turn, which will be the same
whether there's no wind on the ground, or if it's blowing 20 knots.
You're not having to "accelerate with the wind", you're just making a
turn and the energy used up in the turn will be the same whether you're
going from upwind to downwind or downwind to upwind.

Perhaps your original phrase was just a little mis-phrased, because it
does make it look like you've fallen for the "dangerous downwind turn"
myth.

--
From the sunny Isle of Man.
Yes, the Reply-To email address is valid.
  #5  
Old April 25th 08, 12:23 PM posted to rec.aviation.piloting,rec.aviation.student
Stefan
external usenet poster
 
Posts: 578
Default Lancair crash at SnF

WingFlaps schrieb:

A direction change in a
plane is always due to acceleration (and that means more drag). That's
Newtonian physics.


Right.

You go from up wind direction (takeoff is usually
up wind) to turn in the wind direction to land down wind. There's an
acceleration, it is a change in _velocity_


Wrong.

it creates drag, it costs
height and that's the important bit. Now do you understand -TURNS are
not free,


Right.

Your're mixing up two completely different things. Of course, turns are
never "free". They cost energy due to higher drag, resulting from higher
speed, higher wingload and control deflection.

*But*: It absolutely doesn't matter whether you turn from headwind into
tailwind or vice versa. Your airspeed does *not* change. (Of course the
vector does, but not its magnitude.) Your groundspeed changes, but
that's not relevant. Your sentence "Now we add in the energy losses from
having to accelerate with the wind" can only be interpreted that you
think groundspeed would matter because you somehow had to "acceleerate"
to catch up with the wind speed when turning from head to tail wind.
Which is utter nonsense, Newtonianly spoken.
  #6  
Old April 25th 08, 01:00 PM posted to rec.aviation.piloting,rec.aviation.student
WingFlaps
external usenet poster
 
Posts: 621
Default Lancair crash at SnF

On Apr 25, 11:23*pm, Stefan wrote:
WingFlaps schrieb:

A direction change in a
plane is always due to acceleration (and that means more drag). That's
Newtonian physics.


Right.


Now we are at first base!


You go from up wind direction (takeoff is usually
up wind) to turn in the wind direction to land down wind. There's an
acceleration, it is a change in _velocity_


Wrong.

I see the problem. You don't know what velocity is. It's a VECTOR. It
changes when you turn. If you don't understand this there's not much
point talking about anything that involves physics....

Cheers
  #7  
Old April 25th 08, 01:12 PM posted to rec.aviation.piloting,rec.aviation.student
Stefan
external usenet poster
 
Posts: 578
Default Lancair crash at SnF

WingFlaps schrieb:

I see the problem. You don't know what velocity is. It's a VECTOR. It
changes when you turn. If you don't understand this there's not much
point talking about anything that involves physics....


Actually, I know an awful lot about physics.

In everyday's language, the word velocity stands for the _magnitude_ of
the vector. Now if you want me to realise outside some technical or
scientific environment that you use the word velocity in the vector
sense, you better say so explicitely. Still easier would be to say
"direction".
  #8  
Old April 25th 08, 01:48 PM posted to rec.aviation.piloting,rec.aviation.student
WingFlaps
external usenet poster
 
Posts: 621
Default Lancair crash at SnF

On Apr 26, 12:12*am, Stefan wrote:
WingFlaps schrieb:

I see the problem. You don't know what velocity is. It's a VECTOR. It
changes when you turn. *If you don't understand this there's not much
point talking about anything that involves physics....


Actually, I know an awful lot about physics.


So much that you mix up speed and velocity? LOL!

In everyday's language, the word velocity stands for the _magnitude_ of
the vector.


Nope. Not even at high school. The magnitude is "speed".

Now if you want me to realise outside some technical or
scientific environment that you use the word velocity in the vector
sense, you better say so explicitely.


Gosh, this isn't a technical forum? Was my post not including
"technical" terms like acceleration?

Still easier would be to say
"direction".


What does "flying with the wind" imply to you, a direction or a speed?
I'd say the former but I'm only a native English speaker.

Cheers

  #9  
Old April 26th 08, 09:07 PM posted to rec.aviation.piloting,rec.aviation.student
Help! I Need SomeBooty!
external usenet poster
 
Posts: 4
Default Lancair crash at SnF

On Fri, 25 Apr 2008 05:00:45 -0700 (PDT), WingFlaps wrote:

I see the problem. You don't know what velocity is. It's a VECTOR. It
changes when you turn. If you don't understand this there's not much
point talking about anything that involves physics....


Talk about thick... you don't even have the slightest clue what velocity
really is.

*snicker*

You've been making a supreme fool of yourself all this time, puffing
your chest and calling other people stupid in your usual self
aggrandizing way. Read this and weep, bitch. Maybe some day you'll learn
to not be such an arrogant jackass.
--
John
  #10  
Old April 25th 08, 01:26 PM posted to rec.aviation.piloting,rec.aviation.student
WingFlaps
external usenet poster
 
Posts: 621
Default Lancair crash at SnF

On Apr 25, 11:23*pm, Stefan wrote:
WingFlaps schrieb:

A direction change in a
plane is always due to acceleration (and that means more drag). That's
Newtonian physics.


Right.

You go from up wind direction (takeoff is usually
up wind) to turn in the wind direction to land down wind. There's an
acceleration, it is a change in _velocity_


Wrong.

it creates drag, it costs
height and that's the important bit. Now do you understand -TURNS are
not free,


Right.

Your're mixing up two completely different things. Of course, turns are
never "free". They cost energy due to higher drag, resulting from higher
speed, higher wingload and control deflection.


I'm not mixed up, You wanted to read something into what I wrote that
was not there and try to score some point I think Well you were wrong
and you still are. I never said airspeed did I?

One last time, as succinctly as I can: to change direction requires
more energy as extra drag = k.m.dV/dt. dV/dt is acceleration and that
is precisely the term I used. The aircraft does _accelerate_ into the
downwind direction. Airspeed may not change but _velocity_ sure as
hell does -'cos IT'S A VECTOR. Now, the energy needed for the change
in _velocity_ comes from the loss of height during the turn and that's
easy to calculate. It is much harder to estimate the extra drag loss
as this will depend on pilot skill and aircraft design. I hope you
finally understand, cos I'm really starting to find it tiresome trying
to explain to you some basic physics which you seem intent on mis-
interpreting.

I'll give you this last post, any continuance along your previous
lines of putting erroneous words into my mouth I will take as your
being a troll...

Cheers

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
lancair crash scapoose, OR gatt Piloting 10 October 26th 06 03:34 PM
Lancair IV Dico Reyers Owning 6 October 19th 04 11:47 PM
Lancair 320 ram air? ROBIN FLY Home Built 17 January 7th 04 11:54 PM
Lancair 320/360 kit wanted!!! Erik W Owning 0 October 3rd 03 10:17 PM
Lancair IVP Peter Gottlieb Home Built 2 August 22nd 03 03:51 AM


All times are GMT +1. The time now is 03:33 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 AviationBanter.
The comments are property of their posters.