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

E-Jet flaps level positions


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

E-Jet flaps level positions

Old 7th July 2014 | 13:51
  #1 (permalink)  
Thread Starter
 
Joined: Jan 2007
Posts: 18
Likes: 0
From: Somewhere
E-Jet flaps level positions

Gentlemen,

Does anyone know the reason that Embraer E-Jet family aircrafts have flaps positions 4 and 5 with same flaps/slats deployment?

When on final, the usual flaps selection is Flaps 3 at GS intercept, next Flaps 5 before 1000' AGL. So, Flaps 4 position is always skipped.
When on Go Around with Flaps Full, then Flaps 4 will be selected, but it has same slat/flap deployment as in Flaps 5 lever position.

Why does E-Jet have this extra flaps lever position? Reserved for future generation?
leon737 is offline  
Reply
Old 7th July 2014 | 14:25
  #2 (permalink)  
 
Joined: Jul 2012
Posts: 2
Likes: 0
From: Canada
Flap 4 is a takeoff setting, flap 5 is a landing setting.

That's the difference.
KingKoopa is offline  
Reply
Old 7th July 2014 | 14:37
  #3 (permalink)  
 
Joined: Jun 2002
Posts: 3
Likes: 5
From: Wor Yerm
You are right, Flap 4 is the same as Flap 5. The reason is that this slat/flap position can be used for take-off and landing. But each has different protection rules. For take-off, you want the config warning system to detect that the correct flap position has been chosen and for a landing, you want the EGPWS and Flight Warning computer to determine that a valid landing flap position has been selected.

As for flaps usage, I'll normally pop onto the glide with Flaps 1 with Green Dot plus 10 or so. At five miles select gear down and Flaps 3. At Flaps 3, re-select Green Dot and at three miles, Flaps 5 or Full and Vfas. It keeps the noise down, you are easily stabilised by 500' and works nicely. But when ATC demands something different or on horrible days a different schedule may have to be followed.
Piltdown Man is offline  
Reply
Old 7th July 2014 | 15:05
  #4 (permalink)  
Thread Starter
 
Joined: Jan 2007
Posts: 18
Likes: 0
From: Somewhere
Thank you, KingKoopa and Piltdown Man! Now it's clear.

2 Piltdown Man:
Can you please clear up your flaps usage technique: what is your IAS with Flaps 1 on the glide with typical weight and does this comply to '160 knots before 4nm' rule?
leon737 is offline  
Reply
Old 7th July 2014 | 15:54
  #5 (permalink)  
 
Joined: Sep 1998
Posts: 1,615
Likes: 1
From: wherever
Leon 737

I know a top notch training school who can teach you everything you need to know about the Ejet. ;-)

Different company procedures may well deviate from the Embraer standard SOP and flap selections are different depending on EASA or FAA AFM.
FE Hoppy is offline  
Reply
Old 7th July 2014 | 17:19
  #6 (permalink)  
 
Joined: Nov 2012
Posts: 579
Likes: 0
From: Planet Claire
If asked for '160 to 4', do it flap 3, gear down.

You can drop the gear at 5d, or earlier if you wish.

At 4d, go flap 5, speed on approach, landing checklist.
AtomKraft is offline  
Reply
Old 7th July 2014 | 17:25
  #7 (permalink)  
 
Joined: Oct 2012
Posts: 1,765
Likes: 3
From: UK
If the flap/slat positions are the same, surely the systems logic could be designed to recognise the aircraft situation? Could this be a certification issue with the limitation of not being possible to select from a flap+slat config to a flap only config without a baulk or a double selection? Just asking?
Onceapilot is offline  
Reply
Old 7th July 2014 | 17:35
  #8 (permalink)  
Thread Starter
 
Joined: Jan 2007
Posts: 18
Likes: 0
From: Somewhere
Thanks, AtomKraft!

Your words fully match with what I've used.
I'm feeling safe when using mental 'milestones' - 180 up to 10 nm, then 160 up to 4 nm, then decelerate and go in landing conf. Even when not asked by ATC
(but gears down only at 5 nm, then immediately the landing flaps selection; all completed before 1000' AFE)

Just was slightly astonished why E-Jet has the special 'duplicate Flap 4' position, not like Bus. Now it's clear - just the procedures issue, not a bug, just a feature
leon737 is offline  
Reply
Old 7th July 2014 | 17:43
  #9 (permalink)  
 
Joined: Nov 2012
Posts: 579
Likes: 0
From: Planet Claire
Leon
Flap 4 take offs are routine in the E-jet, but not all operators need to do them.

Flap 4 is usually used from performance limited runways. The TO config sys needs to know what you plan to do, thus flap 4. Trying to leave with flap 2, from an airfield where you've calculated flap 4 performance could end quite badly.
AtomKraft 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.