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Basic Aeronautical Knowledge questions

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Basic Aeronautical Knowledge questions

Old 16th Apr 2022, 07:51
  #21 (permalink)  
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If a normally aspirated engine is set LOP in the cruise and the aircraft to which it is fitted is then put into a descent, the power output of the engine will ...

And yes, RPM is very useful.

And then there's this thing called 'pitch trim'.

As to your other points, 43, stay tuned for my next BAK thread.
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Old 16th Apr 2022, 07:55
  #22 (permalink)  
 
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You are still entering the descent with x amount of power, but now the mysteries of gravity pulling you down, yes I know adding more air to already LOP charge will result in less power, but enough less power to offset the pull of granitus?

But the other point still stands, I assume you still look at the IAS pointer to make sure it doesn't bend past the red bits.
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Old 16th Apr 2022, 08:08
  #23 (permalink)  
 
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Originally Posted by Clinton McKenzie View Post
I'll be starting another BAK thread on altitudes and area forecast margins of error and instrument margins of error and...
Could you be persuaded not to? At the very least, it comes across as very imperious to say the least, rather too 'know it all'.
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Old 16th Apr 2022, 08:44
  #24 (permalink)  
 
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Originally Posted by Clinton McKenzie View Post
You obviously haven't been prosecuted for exceeding the VNE of an aircraft you've flown, Cedrik, on the basis of 'evidence' comprising the forecast winds and the aircraft's ground speed. This will all make sense, eventually...
I had to check that the post wasnt
made on 1st of April. It wasnt…obviously:

Use the E6B or similar to calculate TAS from
your values. The OAT has a very big impact on the TAS from the OAS readout.

There is some online calcs, but before you use them to defend yourself you should check thet they do the math correct.
Jere is one example:
TAS Calculator

It is obvious that someone that use a GS readout to prosecute people for VNE/VMO/MMO violations do not understand aviation at all.



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Old 16th Apr 2022, 10:57
  #25 (permalink)  
 
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Instead of reducing MP on descent, just increase the RPM instead! 😱
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Old 16th Apr 2022, 11:03
  #26 (permalink)  
 
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There's an app to calculate TAS and it's bloody useful.
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Old 16th Apr 2022, 13:14
  #27 (permalink)  
 
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The OP's first post asks why didn't the wings break off at a ground speed of 239 kts. The only thing affecting a light aircraft structure is the IAS. The groundspeed is the speed of your aircraft flying along plus whatever speed the airmass is moving at, referenced to a fixed point on the ground, it is not the speed of the air passing over your wings ! Only the IAS shows your actual speed through the air molecules, and that is all the aircraft structure can 'feel'.


As long as your max allowable IAS was not exceeded, you have no case to answer. I have a photo from an A321 with a TAS of 465 kts and a ground speed of 600 kts giving a tailwind of 135 kts - it is in the wrong format to post here. Admittedly, that was a jet stream up at FL380 or so, but tail winds of more than 72 or 43 kts are not uncommon.

You cannot work out what an aircraft's IAS was from a groundspeed readout after the event, because you need to know the aircraft's TAS, so need to know the air density and temperature up there where the aircraft was at the time, as well as an accurate windspeed of the airmass you were in. None of this can be known from the ground.
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Old 16th Apr 2022, 21:18
  #28 (permalink)  
 
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Op when did you get your private?
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Old 16th Apr 2022, 21:40
  #29 (permalink)  
 
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So is VNE based on IAS and decreases as TAS increases, or is that one of those flat-earther type theories?
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Old 16th Apr 2022, 21:51
  #30 (permalink)  
 
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Clinton,
Would I be correct to assume that this thread has to be read in conjunction with your other thread?
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Old 16th Apr 2022, 22:34
  #31 (permalink)  
 
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Could you be persuaded not to? At the very least, it comes across as very imperious to say the least, rather too 'know it all'
There's a time honoured and 100% solution to your problem here. If you don't like the subject matter of the thread, move on, don't read it, **** right off.
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Old 16th Apr 2022, 23:34
  #32 (permalink)  
 
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OP, you keep going on about BAK as if your questions are a regular problem that those sitting the RPL exams have to solve. Have you actually read the BAK syllabus in Part 61 MOS?

What's the point of this thread? Serious question, not having a go!
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Old 16th Apr 2022, 23:58
  #33 (permalink)  
 
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Originally Posted by Uplinker View Post
You cannot work out what an aircraft's IAS was from a groundspeed readout after the event, because you need to know the aircraft's TAS, so need to know the air density and temperature up there where the aircraft was at the time, as well as an accurate windspeed of the airmass you were in. None of this can be known from the ground.
Does ADSB not provide IAS?

Only suggesting it might because FlightRadar24 has a field for IAS but I'm too poor to afford gold membership and see it unlocked!
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Old 17th Apr 2022, 01:01
  #34 (permalink)  
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Originally Posted by clark y View Post
Clinton,
Would I be correct to assume that this thread has to be read in conjunction with your other thread?
Yes, clark. The point will eventually become clear (though I'm sure that many have already worked it out). I'm not testing my BAK.

ipvapproach: 1986, and have walked away from every landing since.


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Old 17th Apr 2022, 09:39
  #35 (permalink)  
 
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VNE has nothing to do with GS.
If you descend at a constant IAS, in ISA atmosphere, your TAS (equal to GS without wind) will gradually decrease.
Up or down 600ft is approximately 1% supplementary difference between IAS and TAS. 9000ft will be about 15%, so VNE at FL90 will be about 225 kt, and I don't know your cruising speed but a very low tailwind would be enough to get this GS.

Very nice airplane the Bonanza !
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Old 18th Apr 2022, 02:37
  #36 (permalink)  
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Originally Posted by mikewil View Post
Does ADSB not provide IAS?

Only suggesting it might because FlightRadar24 has a field for IAS but I'm too poor to afford gold membership and see it unlocked!
I think it depends on the equipment in the particular aircraft.

For aircraft fitted with a 'steam driven' i.e. purely mechanical ASI, there's no source of digitised ASI data. More 'modern' ASIs and EFIS systems? Yes.
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Old 18th Apr 2022, 04:31
  #37 (permalink)  
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IAS is only transmitted if ground speed is not available, and the air data is connected to the transponder.
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Old 18th Apr 2022, 09:38
  #38 (permalink)  
 
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Escape velocity. I don't get it.

Why do you need to travel at 10,000 mph to "break" the tie with Earth's gravity?

If there was a ladder that extended 100 miles would you have to climb it at 10000mph?

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

​​​​​​An aircraft can pull itself away from earth surface ( where gravity is strongest) with compatibly little energy, it can almost fly straight up, so, if there was an atmosphere could it potter along at 1000ft a minute into space? ​​​​​

Mjb
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Old 18th Apr 2022, 10:06
  #39 (permalink)  
 
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It's the speed required for an unpropelled object, e.g. launched from the ground without additional thrust after launch. Step off your ladder at height and you'll soon find yourself rapidly descending, not ascending or hovering.

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Old 18th Apr 2022, 11:13
  #40 (permalink)  
 
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Originally Posted by Clinton McKenzie View Post
The point will eventually become clear (though I'm sure that many have already worked it out). I'm not testing my BAK.
.
YAAAAAWWWWNN

We are busy out here flying the line etc. Everyone is well over these old codgers splitting hairs to make themselves feel important.
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