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Basic Aeronautical Knowledge questions

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Basic Aeronautical Knowledge questions

Old 18th Apr 2022, 11:19
  #41 (permalink)  
 
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Originally Posted by Hamley View Post
YAAAAAWWWWNN

We are busy out here flying the line etc.
Obviously not that busy!
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Old 18th Apr 2022, 11:26
  #42 (permalink)  
 
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Originally Posted by Capt Fathom View Post
Obviously not that busy!
Its 9:30 at night Einstein.

For those of us who arenít 50 million years old it takes a matter of seconds to surf the World Wide Web
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Old 18th Apr 2022, 11:33
  #43 (permalink)  
 
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Originally Posted by mickjoebill View Post
Escape velocity. I don't get it.............If there was a ladder that extended 100 miles...........

Isn't it just the distance from Earth that matters, Earth's gravity fades, why do we need to cover the distance at speed?

​​Mjb
The ladder method would work - except for building and supporting the ladder...........

A rocket could fly straight up at a constant 1 mph and eventually get away from the Earth's gravity, but it would need so much fuel to do so, and more engines to lift the fuel etc., that it would not be physically possible.

Escape velocity is where the vehicle's kinetic energy equals (well, exceeds) the gravitational pull of the planet.
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Old 18th Apr 2022, 13:17
  #44 (permalink)  
 
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Originally Posted by Hamley
Its 9:30 at night Einstein.
There you go, Fathom. You've been called lots in the past, but not Einstein!


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Old 18th Apr 2022, 13:28
  #45 (permalink)  
 
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>The VNO was 167 Kts IAS. I never flew her
>above that IAS, because I never knew, for sure,
>when I might encounter unexpected turbulence

if the turbulence hits you at Vno, it can be too late. Have a look at Vb and Va speeds..

>Why didnít my wings or ruddervators break off?

because all V speeds are IAS/CAS, not GS

Last edited by Bosi72; 18th Apr 2022 at 19:16.
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Old 18th Apr 2022, 18:09
  #46 (permalink)  
 
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I had a GS of 733kts do I need a lawyer?
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Old 19th Apr 2022, 04:29
  #47 (permalink)  
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Only if someone decides to prosecute you on the basis that 733 minus the forecast wind equals a number greater than the VNE for the aircraft you were flying. But I reckon you'd have to be at best incompetent and at worst malicious to prosecute on that basis.
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Old 19th Apr 2022, 04:50
  #48 (permalink)  
 
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Am I missing something? Forecast winds are just that a forecast of what the wind might be? Short of a dashcam or something similar how is anybody going to prove what the ACTUAL winds and indicated airspeed were?
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Old 19th Apr 2022, 05:07
  #49 (permalink)  
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Good to see you engaging with the substance, and very good questions, Cedrik. You are not missing anything.
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Old 19th Apr 2022, 12:27
  #50 (permalink)  
 
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Great I donít think there is a set Vne as it will vary with temperature. Looks like Iím the clear hope you are too 👍
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Old 19th Apr 2022, 12:33
  #51 (permalink)  
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Great I donít think there is a set Vne as it will vary with temperature.

Why might that be ?
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Old 20th Apr 2022, 01:45
  #52 (permalink)  
 
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Originally Posted by Clinton McKenzie View Post
Only if someone decides to prosecute you on the basis that 733 minus the forecast wind equals a number greater than the VNE for the aircraft you were flying. But I reckon you'd have to be at best incompetent and at worst malicious to prosecute on that basis.
Didn't you just say above that ADSB transmits IAS?

In that case there is no need to apply the forecast wind as the actual IAS will be known...
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Old 20th Apr 2022, 02:49
  #53 (permalink)  
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Originally Posted by mikewil View Post
Didn't you just say above that ADSB transmits IAS?

In that case there is no need to apply the forecast wind as the actual IAS will be known...
No I didn't. You should read what I said. And you should read what swh said.

The reason should be obvious: IAS is a perfectly useless piece of information to ATC and other aircraft.
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Old 20th Apr 2022, 03:11
  #54 (permalink)  
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IAS is a perfectly useless piece of information to ATC and other aircraft.

I would have thought that IAS (IMN in the FLs) was a rather useful measure for traffic separation as it is what the typical pilot has available for speed reference on the panel ?
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Old 20th Apr 2022, 03:20
  #55 (permalink)  
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Separation is about predicting where aircraft will be at points in time. That's about groundspeed (and track).

I'm sure a bunch of qualified ATCers will pile on to me if I'm mistaken.

(On the weekend I watched a very graceful bird flying 'backwards'. Heading west into a stiff breeze but tracking east along a waterfront, looking for juicy morsels. Airspeed 25 kms per hour, heading 270. Groundspeed 5 kms per hour, track 090. How does knowing the bird's IAS is 25 kms per hour help avoid a collision with it?)

(PS: The bird was neither an African nor European swallow.)

Last edited by Clinton McKenzie; 20th Apr 2022 at 03:52. Reason: To add the PS.
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Old 20th Apr 2022, 03:55
  #56 (permalink)  
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Clinton,

Get ready for the pile on. IAS based standards used to be all the rage when I was a boy controller.

Gne
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Old 20th Apr 2022, 04:02
  #57 (permalink)  
 
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Originally Posted by sudden twang View Post
I had a GS of 733kts do I need a lawyer?
No. Probably a comb.
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Old 20th Apr 2022, 04:08
  #58 (permalink)  
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Originally Posted by Gne View Post
Clinton,

Get ready for the pile on. IAS based standards used to be all the rage when I was a boy controller.

Gne
Thanks Gne.

I'll don my helmet and brace!
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Old 20th Apr 2022, 04:17
  #59 (permalink)  
 
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Originally Posted by Clinton McKenzie View Post
(On the weekend I watched a very graceful bird flying 'backwards'. Heading west into a stiff breeze but tracking east along a waterfront, looking for juicy morsels. Airspeed 25 kms per hour, heading 270. Groundspeed 5 kms per hour, track 090. How does knowing the bird's IAS is 25 kms per hour help avoid a collision with it?)
Because if the African swallow directly behind it is flying at 35 km per hour, it will likely collide with your bird, prematurely dropping its coconut on the unsuspecting member of the public below.

Last edited by Chronic Snoozer; 20th Apr 2022 at 11:45.
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Old 20th Apr 2022, 05:01
  #60 (permalink)  
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Good point (assuming the tracks are identical). The IASs of the same aircraft on the same track at the same altitude will show that they are e.g. converging and, if so, when they will collide (if you know the distance between). So will ground speed. And ground speed will also show where they will collide.
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