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

E170/190 Angle of Attack


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

E170/190 Angle of Attack

Old 22nd June 2017 | 04:29
  #1 (permalink)  
Thread Starter
20 Anniversary
 
Joined: Mar 2006
Posts: 2,633
Likes: 137
From: USA
E170/190 Angle of Attack

Hi all,

The E170/E190 series doesn't have angle of attack vanes. How does it sense AoA?
Check Airman is offline  
Reply
Old 22nd June 2017 | 08:19
  #2 (permalink)  
Gender Faculty Specialist
 
Joined: Mar 2002
Aviation Qualifications: ATPL
Posts: 2,325
Likes: 432
From: In your head.
Smart probes.
http://utcaerospacesystems.com/cap/s...%20Systems.pdf
Chesty Morgan is offline  
Reply
Old 22nd June 2017 | 14:33
  #3 (permalink)  
10 Anniversary
 
Joined: Jun 2014
Posts: 1,052
Likes: 72
From: Village of Santo Poco
PFM principle.
Amadis of Gaul is offline  
Reply
Old 23rd June 2017 | 09:59
  #4 (permalink)  
 
Joined: Jun 2002
Posts: 3
Likes: 5
From: Wor Yerm
And now for the real killer. These aircraft use the "Smart" data to drive the flight path vector. The flight path vector cannot be removed from the PFD. After a few hundred hours you forget the actual pitch associated with any aspect of your flight. You and the autopilot merely drive the FPV onto the flight path target. What could possibly go wrong? Erm... birdstrike (bee strike), pitot heat, writing, leak, system failure etc. followed by one EICAS message and a double ding you now are flying with invalid FPV data. You have three systems and one or two of them are telling lies. You can't get rid of the FPV and possibly both sides have different FPV values (or both are wrong, both are right or No. 3 is invalid, but it's not displayed) and the pitch you need is... Oh, and you need to kill the auto throttle before it kills you as a well.

I notice they don't crow about how simple it is to deal with system failures.
Piltdown Man is offline  
Reply
Old 23rd June 2017 | 11:15
  #5 (permalink)  
5 Anniversary
 
Joined: Feb 2017
Posts: 1,013
Likes: 15
From: Isla Grande
I had a look on smart probes website, but it still puzzles me how they derive AOA from a probe what looks like a pitot probe.
gearlever is offline  
Reply
Old 24th June 2017 | 06:04
  #6 (permalink)  
Thread Starter
20 Anniversary
 
Joined: Mar 2006
Posts: 2,633
Likes: 137
From: USA
Originally Posted by Chesty Morgan
Thanks for the link. I think it sent me in the right direction.
Check Airman is offline  
Reply
Old 24th June 2017 | 06:05
  #7 (permalink)  
Thread Starter
20 Anniversary
 
Joined: Mar 2006
Posts: 2,633
Likes: 137
From: USA
Originally Posted by gearlever
I had a look on smart probes website, but it still puzzles me how they derive AOA from a probe what looks like a pitot probe.
Apparently there's another hole underneath the dynamic pressure port that is used to drive AoA data.
Check Airman is offline  
Reply
Old 24th June 2017 | 06:07
  #8 (permalink)  
Thread Starter
20 Anniversary
 
Joined: Mar 2006
Posts: 2,633
Likes: 137
From: USA
Originally Posted by Piltdown Man
And now for the real killer. These aircraft use the "Smart" data to drive the flight path vector. The flight path vector cannot be removed from the PFD. After a few hundred hours you forget the actual pitch associated with any aspect of your flight. You and the autopilot merely drive the FPV onto the flight path target. What could possibly go wrong? Erm... birdstrike (bee strike), pitot heat, writing, leak, system failure etc. followed by one EICAS message and a double ding you now are flying with invalid FPV data. You have three systems and one or two of them are telling lies. You can't get rid of the FPV and possibly both sides have different FPV values (or both are wrong, both are right or No. 3 is invalid, but it's not displayed) and the pitch you need is... Oh, and you need to kill the auto throttle before it kills you as a well.

I notice they don't crow about how simple it is to deal with system failures.
What's worse is that the FPV is in front of the crntre dot of the miniature airplane, and thus partially obscures the attitude indication. A truly horrible design.
Check Airman is offline  
Reply
Old 25th June 2017 | 00:18
  #9 (permalink)  
 
Joined: Sep 1998
Posts: 1,615
Likes: 1
From: wherever
It's a flight path angle on the EJet PFD. Not a Vector.

And the pitch attitudes are in the QRH
FE Hoppy is offline  
Reply
Old 25th June 2017 | 00:24
  #10 (permalink)  
10 Anniversary
 
Joined: Jun 2014
Posts: 1,052
Likes: 72
From: Village of Santo Poco
Those who need the QRH to know their pitch attitudes have bigger problems than an FPA indication.
Amadis of Gaul is offline  
Reply
Old 25th June 2017 | 06:37
  #11 (permalink)  
Thread Starter
20 Anniversary
 
Joined: Mar 2006
Posts: 2,633
Likes: 137
From: USA
On the 190, the design philosophy seems to have been that attitude is a secondary parameter, as the FD only shows the flight path you need, and not the pitch. It's a most asinine system.
Check Airman is offline  
Reply
Old 25th June 2017 | 09:00
  #12 (permalink)  
15 Anniversary
 
Joined: Jan 2008
Posts: 99
Likes: 4
From: U.K
On the 190, the design philosophy seems to have been that attitude is a secondary parameter

Have things changed in the magenta following world that pilots or should they now be called aircraft operators no longer fly pitch and power= performance, they just blindly follow a vector!
simmple is offline  
Reply
Old 25th June 2017 | 12:20
  #13 (permalink)  
Thread Starter
20 Anniversary
 
Joined: Mar 2006
Posts: 2,633
Likes: 137
From: USA
Perhaps at the Embraer factory. Thankfully Boeing and Airbus still know what they're doing.
Check Airman is offline  
Reply
Old 25th June 2017 | 16:49
  #14 (permalink)  
Gender Faculty Specialist
 
Joined: Mar 2002
Aviation Qualifications: ATPL
Posts: 2,325
Likes: 432
From: In your head.
Originally Posted by Amadis of Gaul
Those who need the QRH to know their pitch attitudes have bigger problems than an FPA indication.
Where else are you going to get them?
Chesty Morgan is offline  
Reply
Old 25th June 2017 | 17:40
  #15 (permalink)  
10 Anniversary
 
Joined: Jun 2014
Posts: 1,052
Likes: 72
From: Village of Santo Poco
Experience, my brother, experience.
Amadis of Gaul is offline  
Reply
Old 25th June 2017 | 17:41
  #16 (permalink)  
10 Anniversary
 
Joined: Jun 2014
Posts: 1,052
Likes: 72
From: Village of Santo Poco
Originally Posted by simmple
Have things changed in the magenta following world that or should they now be called operators no longer fly pitch and power= performance, they just blindly follow a vector!
And that's not even the worst of it, I fear...
Amadis of Gaul is offline  
Reply
Old 25th June 2017 | 17:52
  #17 (permalink)  
Gender Faculty Specialist
 
Joined: Mar 2002
Aviation Qualifications: ATPL
Posts: 2,325
Likes: 432
From: In your head.
So you can remember ALL combinations of pitch and power for every airspeed, weight, altitude, aircraft configuration, climb, cruise, descent and holding?

Because at the last count there are 115 different combinations in my QRH with plenty of interpolation available.
Chesty Morgan is offline  
Reply
Old 25th June 2017 | 18:06
  #18 (permalink)  
 
Joined: Sep 1998
Posts: 1,615
Likes: 1
From: wherever
And for those banging on, the CSeries has FPV as primary too.
Like the Ejet, the pitch indication is always in view and the same style pitch tables are available in the QRH.

Welcome to the 21st century ;-) no bits of string tied to the windscreen required.
FE Hoppy is offline  
Reply
Old 25th June 2017 | 20:00
  #19 (permalink)  
10 Anniversary
 
Joined: Jun 2014
Posts: 1,052
Likes: 72
From: Village of Santo Poco
Originally Posted by Chesty Morgan
So you can remember ALL combinations of pitch and power for every airspeed, weight, altitude, aircraft configuration, climb, cruise, descent and holding?

Because at the last count there are 115 different combinations in my QRH with plenty of interpolation available.
I don't need to remember all of them, TLAR principle does wonders. Airmanship is an amazing thing.
Amadis of Gaul is offline  
Reply
Old 25th June 2017 | 20:34
  #20 (permalink)  
Gender Faculty Specialist
 
Joined: Mar 2002
Aviation Qualifications: ATPL
Posts: 2,325
Likes: 432
From: In your head.
No you don't because some clever chap has published then for you.

The correct use of airmanship is an amazing thing. The incorrect use of ego isn't.
Chesty Morgan is offline  
Reply

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.