Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

VNAV Descent Speed Planning?


Notices
Tech Log The very best in practical technical discussion on the web

VNAV Descent Speed Planning?

Old 23rd April 2010 | 16:01
  #1 (permalink)  
Thread Starter
 
Joined: Apr 2007
Posts: 8
Likes: 0
From: asia
VNAV Descent Speed Planning?

May someone please help to let me comprehend why VNAV will not command an economy target speed greater than 349 knots (VMO/MMO minus 16) or a pilot entered speed greater than 354 knots ( VMO/MMO minus 11) on the B747-400? I do not understand the logic behind it. Thanks in advance!
shockwave1973 is offline  
Reply
Old 23rd April 2010 | 16:44
  #2 (permalink)  
25 Anniversary
Veteran: Navy
 
Joined: May 2000
Posts: 3,204
Likes: 2
From: Seattle
Maybe because the VNAV function nominally allows speed to vary +/- 15 KIAS to stay on the VNAV path in the descent...
Intruder is offline  
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.