Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Fadec Vs. Eec  
User currently offlineModesto2 From United States of America, joined Jul 2000, 2788 posts, RR: 5
Posted (13 years 2 weeks 2 days 13 hours ago) and read 11545 times:

What's the difference between these two systems? From what I've gathered, they work together (or closely). Any details are appreciated!

2 replies: All unread, jump to last
 
User currently offlineFDXmech From United States of America, joined Mar 2000, 3251 posts, RR: 34
Reply 1, posted (13 years 2 weeks 2 days 11 hours ago) and read 11534 times:

These two terms are often intermingled and interchanged to the confusion of some.

Basically their are 3 ways the engine is controlled.

1) The very basic, strictly mechanical (cables, rods etc) interface between the throttle and the engines fuel control unit (I'll use the term fuel control unit or FCU as the generic fuel metering device that controls engine thrust and other related functions).

The FCU itself is a very complex hydromechanical RPM governor that utilizes engine RPM, engine pressures and temperatures to control engine thrust to the desired power setting selected by the pilot moving the throttles.
This system has few safeguards to prevent the overtemping or overspeeding of the engine.
Plus, the throttles must be adjusted to compensate for temp, barometric pressure/altitude changes to maintain a constant thrust.

2) Supervisory system controls: The next step up are engines with supervisory control capability (737-300, some 757 & 767's, some A310 & A300-600's). Essentially this system is an upgrade of the basic cable, rods and hydromechanical FCU and puts an electronic engine control in the mix. This engine control will fine tune the engines N1/EPR (though its authority is limited) to a steady thrust during changing conditions (climbs, descents etc). This system offers more exceedence protections and monitors more engine parameters than the basic hydromechanical FCU.

The control box is referred to as the EEC (electronic engine control) by RR and Pratt? And PMC (power management computer (control?) by CFM.

3) FADEC: This system is the latest and most sophisticated. FADEC is essentially engine control via "fly by wire". Their is no mechanical connection between throttle and fuel control. The heart of the FADEC system is the EEC (Pratt) or ECU (engine control unit/General Electric).

Sometimes its best to understand this system in a way you can visualize. Imagine in your living room, the light bulb is the engine and the dimmer switch is the throttle. Moving the throttle forward is equivalent to turning the dimmer switch toward brighter. The difference being is with FADEC the dimmer switch goes to the ECU/PMC and they act as the middleman with lots of inputs to control the engine with far greater precision than old basic system or the supervisory system. This system has protections to guard against overboosting or overtemping (during start on some aircraft). But the main protection is the precise manner in which the engine is controlled and monitored by the EEC (PW) or ECU (GE).



You're only as good as your last departure.
User currently offlineDc10hound From United States of America, joined Dec 2000, 463 posts, RR: 5
Reply 2, posted (13 years 2 weeks 1 day 7 hours ago) and read 11501 times:

>>The control box is referred to as the EEC (electronic engine control) by RR and Pratt? And PMC (power management computer (control?) by CFM.<<
Power Management Control - on GE CF6-80C2 engines also.




"Eagles soar. But weasels never get sucked into jet intakes.."
Top Of Page
Forum Index

Reply To This Topic Fadec Vs. Eec
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
Fadec Vs Fafc posted Mon Jan 11 2010 09:48:46 by Kimon
Fadec Or EEC On DC-10-30? posted Sat Nov 11 2006 01:50:47 by MD11Fanatic
Piston Engine Fadec, Diesel Vs Avgas posted Sat Oct 6 2007 09:13:48 by Baw2198
Fadec/EEC MEL Availability posted Sat Apr 7 2007 14:54:30 by TristarSteve
EEC Vs Deec posted Sun Sep 18 2005 12:19:20 by Diego
Boeing Vs. Airbus Wing Design Philosophies posted Mon Apr 16 2012 13:41:32 by ferpe
A vs. B differences in FBW handling/behavior posted Sun Apr 15 2012 16:49:47 by AirFrance
ICAO License vs Other Licenses posted Fri Mar 30 2012 07:46:28 by web500sjc
Lets Start An Airbus Vs Boeing Discussion posted Sat Mar 17 2012 00:14:42 by Max Q
Lido ERouteManual Vs. JeppView posted Fri Mar 16 2012 16:11:04 by Blue3

Sponsor Message:
Printer friendly format