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

A320 SE Taxi and 2nd Start

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

A320 SE Taxi and 2nd Start

Thread Tools
 
Search this Thread
 
Old 7th Nov 2004, 22:24
  #1 (permalink)  
Thread Starter
 
Join Date: May 2000
Location: Florida
Posts: 93
Likes: 0
Received 0 Likes on 0 Posts
Question A320 SE Taxi and 2nd Start

Our FCOM warns against applying brakes during the second engine start while single-engine taxiing. There is no explanation given.

Is this an old caution for the older BSCU's? Can anyone explain why this is a valid caution?

Cheers!
AKAAB


AKAAB is offline  
Old 8th Nov 2004, 18:19
  #2 (permalink)  
Lackof747
Guest
 
Posts: n/a
Perhaps it can be distracting doing two things at the same time, haha
 
Old 8th Nov 2004, 19:42
  #3 (permalink)  
Clone of Victor Meldrew
 
Join Date: Jan 2004
Location: england
Posts: 609
Likes: 0
Received 0 Likes on 0 Posts
I always start both BEFORE I taxi.
390cruise is offline  
Old 8th Nov 2004, 19:50
  #4 (permalink)  
Moderator
 
Join Date: Apr 1998
Location: err, *******, we have a problem
Age: 58
Posts: 1,335
Likes: 0
Received 0 Likes on 0 Posts
I would guess it is to do with the PTU... as the PTU senses the rise in the new operating engine hydraulic system pressure it will disengage, and at the point of disengagement there MAY not be full hydraulic system pressure available for brakes for a brief perid of time. I think, anyway, just an educated guess... we certainly don't apply any brakes on shutting one engine down taxying in; in that case if the PTU didn't kick in then brakes would be on the secondary system.

Don't understand the SOP of taxying out on one engine, though, but mine is not to reason why....

Squid
Sick Squid is offline  
Old 8th Nov 2004, 20:13
  #5 (permalink)  
Thread Starter
 
Join Date: May 2000
Location: Florida
Posts: 93
Likes: 0
Received 0 Likes on 0 Posts
It comes down to managing fuel costs. 30-40 mins taxi time on one engine versus two can save a lot of fuel costs. With the US airline industry bleeding cash it's a simple way to safely cut some costs.

The yellow electric pump is ON during single engine taxiing (#1 engine running) - so the PTU theory might not apply since the yellow system is already at normal hyd pressure.
AKAAB is offline  
Old 9th Nov 2004, 04:15
  #6 (permalink)  
 
Join Date: Dec 1999
Location: Over the horizon
Posts: 230
Likes: 0
Received 0 Likes on 0 Posts
As far as I recall, it has to do with electrical transients when the second gen comes on line.

Not sure if that is still a problem with the latest BSCUs.
Diesel8 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.