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

737 Questions

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

737 Questions

Thread Tools
 
Search this Thread
 
Old 14th Jul 2008, 14:10
  #1 (permalink)  
Thread Starter
 
Join Date: Feb 2004
Location: Denmark
Posts: 150
Likes: 0
Received 0 Likes on 0 Posts
737 Questions

Jockeys,

some questions i have:

1.Why do the engines go to high idle when all generators drop offline?


2.What are your hints and tips when we have to fly a normal go around and the level alt is 1500ft AGL and the airport is in sea level. pretty fast and tricky situation


thanks


OD
Olendirk is offline  
Old 14th Jul 2008, 15:04
  #2 (permalink)  
 
Join Date: Feb 2005
Location: flyover country USA
Age: 82
Posts: 4,579
Likes: 0
Received 0 Likes on 0 Posts
1) I can't say absolutely, but I'm 95% sure it's loss of DC that would cause high (flight or approach) idle. Engines I'm familiar with need 28vdc on the solenoid to select ground idle.
barit1 is offline  
Old 14th Jul 2008, 15:18
  #3 (permalink)  
Warning Toxic!
Disgusted of Tunbridge
 
Join Date: Jan 2005
Location: Hampshire, UK
Posts: 4,011
Likes: 0
Received 0 Likes on 0 Posts
Bulfer says it is not less than 59%N2 to allow for IDG operation. This would either mean to ensure adequate inflight IDG operation of generator or to allow disconnect to take place if needed.

Regard it as a circuit. I believe when you have difficulty in operating the automatics adequately when a lot is going on, simply say 'I have control, my throttles', disconnect everything and pull throttles back to a sensible power early. Fly it as you would a normal circuit. you can re-engage automatics at your leisure, but the important thing is not to blast through 1500' with GA power and too much flap while you are wrestling with MCP modes!
Rainboe is offline  
Old 14th Jul 2008, 15:20
  #4 (permalink)  
 
Join Date: Jul 2004
Location: India
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
about engines going to approach idle if both the genies drop off line .. its a guess but ( in a NG ) below 15000ft if the flap position feedback fails the engs got to appch idle...and with both genies off line the flap position indicator does not work.....


The go around question depend on how fast you work the MCP panel cause you go into ALT ACQ really early depending on the ROC... best option as the FCTM also recommends is to take over manually and level her off ..
bhoju75 is offline  
Old 14th Jul 2008, 18:49
  #5 (permalink)  
 
Join Date: Dec 2007
Location: France
Posts: 481
Likes: 0
Received 0 Likes on 0 Posts
I strongly object to your use of 'jockeys'...

However,

1. Without checking the books, I assume that a generator parameter is used in the idle logic;

2. You're a pilot (not a 'jockey'). Fly the aircraft. Autopilot out, autothrottle out, 70-75% N1, sensible pitch (aim for about 1000 fpm), and level off as you learnt to in a little aeroplane. DO NOT try to use the automatics for this. The all engines go-around is the most frequently screwed up exercise in the sim and on the line, largely because it's never trained (other than following a coupled approach in LVO).
frontlefthamster is offline  
Old 14th Jul 2008, 18:57
  #6 (permalink)  
 
Join Date: Jul 2000
Location: My views - Not my employer!
Posts: 1,031
Likes: 0
Received 0 Likes on 0 Posts
1/ I remember an eng doing ground runs one day trying to sort an EGT gauge fault. When both the EGT gauge CB's were pulled together both engines went to flt idle.(on ground). Don't know whether that may give a clue!

2/ At AA, pull back a whole heap of thrust to make the level off and accel manageable.
Cough is offline  
Old 18th Jul 2008, 16:46
  #7 (permalink)  
 
Join Date: Apr 1999
Location: UK
Posts: 101
Likes: 0
Received 0 Likes on 0 Posts
If you do a battery start then the engine will stabilise at high idle until such time as a gen comes on line... not that that explains why...
luddite is offline  
Old 19th Jul 2008, 07:21
  #8 (permalink)  
 
Join Date: Jul 2007
Location: In a house
Age: 48
Posts: 136
Likes: 0
Received 0 Likes on 0 Posts
luddite.....
you giving advice about wiggly amps, who would have thought
electricdeathjet is offline  
Old 20th Jul 2008, 13:16
  #9 (permalink)  
 
Join Date: Jun 2000
Location: Australia
Posts: 4,189
Likes: 0
Received 19 Likes on 6 Posts
Interesting thread. I wonder why the God Almighty rush to engage the autopilot at 400 feet following an engine failure at lift off. Is it because pilots have forgotten the ancient art of hand flying? One operator said it was because F/O's in their company are not trained to monitor to hand flying - only trained to monitor automatics. Other operators policy is to only engage the autopilot following engine failure at lift off when the aircraft has been cleaned up.
Centaurus is offline  

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



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

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.