How do I select takeoff from a wet runway ?    

 

 

Happy flying 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Regards Björn Granelli

 

 

How do I select takeoff from a wet runway ?    

 

Type WET or W and line select it to the appropriate line (you might need to use /WET or /W - I can't picture the prompt in my head at the moment).

Hi,

 

Takeoff ref page 2 on bottom left:

 

SLOPE/COND

----/DRY

 

Type /W or /WET as Kyle said and click on the button on the left (5L)

FMS Takeoff Ref Pg 2/2 info starts at FCOM 11.40.50 and using the Search function for text 'wet' takes you directly to FCOM 11.40.53; which would have been much quicker than posting in the forum.... just saying, not a bad question but there was an easier way to get the answer.

Takeoff ref page 2 on bottom left:

 

What are the differences if Wet is selected?

FMS Takeoff Ref Pg 2/2 info starts at FCOM 11.40.50 and using the Search function for text 'wet' takes you directly to FCOM 11.40.53; which would have been much quicker than posting in the forum.... just saying, not a bad question but there was an easier way to get the answer.

By the same token, I bet 90% of the questions asked on the forum could be answered the same way... However, wouldn't the forum be a boring place. It's nice for enthusiasts to have a chat, even if the answer may have been in the manual. In addition, a simple question [that mat be in the manuals] can lead to a discussion of greater depth, and explore avenues we all might find fascinating.

By the same token, I bet 90% of the questions asked on the forum could be answered the same way... However, wouldn't the forum be a boring place. It's nice for enthusiasts to have a chat, even if the answer may have been in the manual. In addition, a simple question [that mat be in the manuals] can lead to a discussion of greater depth, and explore avenues we all might find fascinating.

 

Except that greater discussion usually doesn't happen because we're all answering the same questions (over and over again) that could be easily found in the intro manuals.

 

I'm usually pretty understanding when questions require delving into the FCOMs, but I cannot stand the false logic that is exhibited by people when they try and say the forum would be boring.  You're basically trying to tell me that college/university is a land devoid of conversation because people have already read and understood the basics of topics for the past years.  We all know that's absolutely false.

 

...but since it's a convenient argument and very few people are going to look at it logically - because let's be real: the logical response would be to search for an answer directly from the source - people just let it happen.  No.  If this terrible argument were true, there'd be no point in higher education.  What a stupid and worthless place that is...clearly.

 

Stop.  It.

But Kyle, this is in itself a logical error, it's called a False Dilemma, but I add that merely as a technical observation.

 

Except that greater discussion usually doesn't happen because we're all answering the same questions (over and over again) that could be easily found in the intro manuals.

 

I'm usually pretty understanding when questions require delving into the FCOMs, but I cannot stand the false logic that is exhibited by people when they try and say the forum would be boring.  You're basically trying to tell me that college/university is a land devoid of conversation because people have already read and understood the basics of topics for the past years.  We all know that's absolutely false.

 

...but since it's a convenient argument and very few people are going to look at it logically - because let's be real: the logical response would be to search for an answer directly from the source - people just let it happen.  No.  If this terrible argument were true, there'd be no point in higher education.  What a stupid and worthless place that is...clearly.

 

Stop.  It.

But Kyle, this is in itself a logical error, it's called a False Dilemma, but I add that merely as a technical observation.

 

This is true, regarding that first point.

 

I stand by my argument that the position of the manuals eliminating the need for the forum is absurd, and exhibits a lack of reasonable thought process.

Except that greater discussion usually doesn't happen because we're all answering the same questions (over and over again) that could be easily found in the intro manuals.

 

Yes it does. We see it all the time. I can also verify that as I've been a moderator on the Just Flight forum for many years. It begins with a question that could have been answered via the manuals, and the discussion frequently digresses. We see the beginnings of that here. The OP has now asked a further question, namely what the "WET" entry in the FMC actually does. It's no stretch of the imagination to see how that could direct the thread in a very interesting and informative direction.

 

 

I'm usually pretty understanding when questions require delving into the FCOMs, but I cannot stand the false logic that is exhibited by people when they try and say the forum would be boring. You're basically trying to tell me that college/university is a land devoid of conversation because people have already read and understood the basics of topics for the past years. We all know that's absolutely false.

 

 

It was actually the other way around when I was educated. The lecturer gave you the basics, and then the student delved deeper from the relevant resources, text books, discussion with piers, group work, and further discussion with the lecturer in regard to points not fully grasped. I see no reason why we can't give the OP a simple answer, it's easy, it's quick, it's no skin of my nose.

 

In fact this very discussion we are having proves my point. It began with a question that could have been answered via the manual, and it has led to a fascinating debate between a defective android and his maker.

 

 

 

 

I stand by my argument that the position of the manuals eliminating the need for the forum is absurd, and exhibits a lack of reasonable thought process.

Err... excuse me. Where did I say the manuals eliminates the need for a forum. How dare you, reboot your positronic matrix immediately, I insist!

 

My only point is that threads asking simple questions that could have been answered by reading the manual can mutate in interesting and informative directions. LIKE THIS ONE! And therefore we should be less scathing of them.

 

And that given that a high percentage of forum activity is related to questions that could be answered by reading the manual... forum activity would be less without them. This very thread, this very fascinating debate we are having now, would never have occurred without that very phenomenon being a reality.

 

And aren't we having a lovely time?

 

And now Mr Kyle, if you would like to answer the OP's second question, namely what exactly the WET entry does, in as much technical detail as you like, with the benefit of your expertise... we can all have a great time and learn something new.

Nice philosophical discussion guys! Do the manuals eliminate the need for forums or schools, you have 4 hours! 

 

Back to the question:

 

 

 

What are the differences if Wet is selected?

 

I have only a draft of answer based on observation and some paragraphs of the FCOM:

When you select Wet, V1 is reduced compared to the dry V1 value and I think to the minimum V1.

But does it do something else, I don't know.

 

 

But does it do something else, I don't know.

 

Your answer is at FCOM SP16.1 Supplementary Procedures, Adverse Weather, Takeoff Wet or Contanimated Runways.  This actually took me almost a minute to find because the search string 'V1' appears often.

 

When I am given an answer to a question of a technical nature, I appreciate knowing the source for the answer and vetting the information rather than accepting an opinion or a guess.  Anybody that does not appreciate me digging into the books to respond to a question is thinking in an area beyond my comprehension.

Hi Dan,

 

When I referred to "some paragraphs of the FCOM", that is what the I read (SP16.1).

I agree with you, but that paragraph doesn't actually answer "hsung"'s question which is to know what happens when you set WET in the FMC.

The SP only tells what shall or shan't be done with wet takeoff...

But you are right, I'd better give reference to books rather than given comments.

 

 

but that paragraph doesn't actually answer "hsung"'s question which is to know what happens when you set WET in the FMC.

 

To a degree it does, the V1 is adjusted down to minimum V1 and I fairly confident that is all that changes. The amount decreased is not described as is typical for FCOM which is an operating manual (not engineering data which PMDG had access to). The FCOM does state that a performance calculation tool is necessary to properly adjust V1 for runway conditions, obstacle clearance and regulatory requirements, which I interpret to mean the FMS V1 reduction is not appropriate for marginal conditions where V1 approaches minimum V1 and/or where obstructions are a takeoff constraint.