Go Back  PPRuNe Forums > Wannabes Forums > Professional Pilot Training (includes ground studies)
Reload this Page >

Tech question derated vs flat rated engines difference

Professional Pilot Training (includes ground studies) A forum for those on the steep path to that coveted professional licence. Whether studying for the written exams, training for the flight tests or building experience here's where you can hang out.

Tech question derated vs flat rated engines difference

Old 15th Jul 2014, 17:16
  #1 (permalink)  
Thread Starter
 
Join Date: Jul 2010
Location: n/a
Posts: 57
Likes: 0
Received 0 Likes on 0 Posts
Tech question derated vs flat rated engines difference

Hi all
I am sorry if this question has been discussed already but i couldnt find it.

I d like to know if someone can explain me the difference, if any, between a flat rated engine and a derated engine.

I found this 2 questions in an interview questions database but i cant really get the difference between the two.

Thanks in advance
matcv88 is offline  
Old 16th Jul 2014, 06:33
  #2 (permalink)  
 
Join Date: Apr 2010
Location: IRS NAV ONLY
Posts: 1,226
Likes: 0
Received 0 Likes on 0 Posts
A flat-rated engine is an engine, which produces the same amount of thrust regardless of temperature from a certain temperature point (around ISA+15 for most engines).

A derated engine is an engine, that has been modified (this modification can be very simple - depends on engine/airframe) to always produce less thrust than what it was designed for. Reasons for this may be better (smaller) noise footprint, reduced maintenance cost, increased EGT margin, reduced VMCG/A, ... On some aircraft you have an option of a fixed (permanent) derate, which requires maintenance action and a "semi-fixed" derate, which can be selected by flight crew to conform the operational needs.
FlyingStone 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


Thread Tools
Search this Thread

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.