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Cockpit and cabin interior questions


Hullu-poika
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Hi colleagues!

I've got an idea to create a common topic regarding visual model of cockpit and cabin interior. Various questions and remarks can be jointed in one topic. And while we have no major updates I'd like to discuss some minor items.

 

From my side a have a question regrding speed placard above the windshield. Is it Vref speeds placard?

Reading the training manual I have got that there should be a Vref speeds placard somewhere in the cockpit. This placard shows maximal speeds which can not be exceeded considering headwing and gust component on landing. But I feel the placard we have in the IXEG model is just a Vref speeds placard without wind correction.

Thus my questions are:

     a) am I right?

     b ) if I am right where can I get maximal possible Vref speed values?

     c)  if I am not right could someone explain this subject a little more detailed?

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Hi,

Vref never changes with wind. It is 1.3 x stalling speed 1G at the current weight. There is a placard for Vref above the pilot´s windows.

You have to add speed increments to Vref to get the Vtgt (Vtarget), wich is the speed you want to fly during your approach.

The formula is: Vtgt = Vref + 1/2 steady headwind component + total gust factor. (The minimum increment is 5kts, the maximum 20kts).

Example: Landing runway 18, wind is 270/20G30, Vref is 130 kts

Vtgt = 130 + 1/2x0 + 10 = 140

You should fly Vtgt until passing the threshhold, then reduce to Vref+total gust factor.

Jan

 

Edited by Litjan
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On 02.11.2017 at 10:11 AM, Litjan said:

Hi,

Vref never changes with wind. It is 1.3 x stalling speed 1G at the current weight. There is a placard for Vref above the pilot´s windows.

You have to add speed increments to Vref to get the Vtgt (Vtarget), wich is the speed you want to fly during your approach.

The formula is: Vtgt = Vref + 1/2 steady headwind component + total gust factor. (The minimum increment is 5kts, the maximum 20kts).

Example: Landing runway 18, wind is 270/20G30, Vref is 130 kts

Vtgt = 130 + 1/2x0 + 10 = 140

You should fly Vtgt until passing the threshhold, then reduce to Vref+total gust factor.

Jan

 

It seems to be I have mixed a lot of different staff in my mind...

Nevertheless I'd like to show a quote from FCTM:

23decb380eb5.jpg

 

There is also one sentence above: 

2.jpg

 

In our example Vtgt = 130 + 1/2x0 + 10 = 140 kt. Obviously it is useless to compare this value with Vtgt = 130 - 5 = 125 kt. Target speed can not be lower than Vref...

Therefore it is still unclear for me what is the placard speed mentioned in the manual...

Sorry for going into such minor stuff with details. But it is interesting for me.

Edited by Hullu-poika
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The placard speed is the maximum speed for the flap setting - there is a placard near the landing gear handle for that. Obviously you must not fly faster than that, so the Vtgt will be limited to that placard speed - 5.

Flap placard for landing flap 30 is 185kts, so the Vtgt for that may never be more than 180kts.

Flap placard for landing flap 40 is 158, so the Vtgt for that may never be more than 153kts.

Cheers, Jan

 

 

Edited by Litjan
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