Archived

This topic is now archived and is closed to further replies.

dravid kenyala

Step climb? Query only.

Recommended Posts

Hi all. Today when I was cruising first at FL370 step climb came up as usual on nd and plan reached FL390. During step climb cruise mode changed to climb mode but after reaching new FL390 climb mode on Eicas display has not been changed to cruise. Why? Am I missing something?

 

Regarding (D-TO or Flex ) takeoff considering as an option. How can we assume that 45 or 60 OAT Is entered. Is it in Fcom manual about what temperatures to be selected. How can we do that?

Thank you'll.

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

 

 


Hi all. Today when I was cruising first at FL370 step climb came up as usual on nd and plan reached FL390. During step climb cruise mode changed to climb mode but after reaching new FL390 climb mode on Eicas display has not been changed to cruise. Why? Am I missing something?

 

Yep.

 

Intro manual.

 

Note the option for CRZ or CLB...

 

 

 


Regarding (D-TO or Flex ) takeoff considering as an option. How can we assume that 45 or 60 OAT Is entered. Is it in Fcom manual about what temperatures to be selected. How can we do that?

 

You can figure this information out by using the performance charts.  There is a thread in this subforum that shows you how to do this.  Search "takeoff performance" in this subforum.

Share this post


Link to post
Share on other sites

Yep.

 

Intro manual.

 

Note the option for CRZ or CLB...

 

 

You can figure this information out by using the performance charts. There is a thread in this subforum that shows you how to do this. Search "takeoff performance" in this subforum.

Regarding Anti ice procedures Kyle ? We should keep them on or in auto. At crz altitudes does pilots keep in on position. At what temp they start to think k its time to turn anti ice? Is it SAT or TAT to be considered during flight. I know that OAT Is considered when on ground(i m assuming).

Thanks man.

Share this post


Link to post
Share on other sites

 

 


You can figure this information out by using the performance charts. There is a thread in this subforum that shows you how to do this. Search "takeoff performance" in this subforum.

 

Kyle

 

The only results returned by a search is your post.

 

Michael Cubine

Share this post


Link to post
Share on other sites

At crz altitudes does pilots keep in on position.

 

Why would you force them to the on position? (See below)

 

 

 

At what temp they start to think k its time to turn anti ice?

 

Temp is only half of the equation.  One of the big things simmers forget is that ice is the result of cold and moisture (not just cold).

 

It could be -100C outside, but if there's no moisture, then you're not going to get ice.  Same goes with your cruise altitude.  Sure, it's -40, but unless there's water, there's no chance you're going to get ice.  Moreover, if the water is already frozen, it's not going to spontaneously unfreeze and then freeze, which is why you get a window of about 10C TAT to -40C SAT and visible moisture for icing conditions.

 

 

The only results returned by a search is your post.

 

False.  34 results are returned, of which, this is one:

http://forum.avsim.net/topic/417334-guidetutorial-takeoff-performance-in-the-777

 

EDIT:

Note that if you go to the search box in this thread it assumes you're trying to search this thread.  Note that I said to search the subforum...

Share this post


Link to post
Share on other sites

 

It could be -100C outside, but if there's no moisture, then you're not going to get ice.  Same goes with your cruise altitude.  Sure, it's -40, but unless there's water, there's no chance you're going to get ice.  Moreover, if the water is already frozen, it's not going to spontaneously unfreeze and then freeze, which is why you get a window of about 10C TAT to -40C SAT and visible moisture for icing conditions.

 

You'll get ice at -100°C. Not on the outside of the aircraft though. and it won't be water that's freezing ;)

Fuel.

 

But you're right, if your aircraft isn't in moisture (Clouds, fog, mist, rain, sleet, snow, etc) then the water that isn't there can't freeze. (well it can, but it isn't there, so doesn't exist.)

 

A solid piece of ice doesn't stick to the metal, it hits it like pellets and bounces off.

 

+10°C might seem warm, but as air pressure changes, the freezing/boiling point of water changes too. Wings produce at least some of their lift by changing air pressure. The air moving over the wing (and under too) changes speed. These effects cause the temperature to go down effectivley so at a worst case, a foggy day that is 9°C may actually produce ice on wing surfaces or engine intakes.

 

At -50°C water is actually solid, and will not stick to a metal surface as there is no adhesion factor.

Share this post


Link to post
Share on other sites