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E170/190 Angle of Attack

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E170/190 Angle of Attack

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Old 22nd Jun 2017, 04:29
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E170/190 Angle of Attack

Hi all,

The E170/E190 series doesn't have angle of attack vanes. How does it sense AoA?
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Old 22nd Jun 2017, 08:19
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Smart probes.
http://utcaerospacesystems.com/cap/s...%20Systems.pdf
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Old 22nd Jun 2017, 14:33
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PFM principle.
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Old 23rd Jun 2017, 09:59
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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.
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Old 23rd Jun 2017, 11:15
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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.
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Old 24th Jun 2017, 06:04
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Originally Posted by Chesty Morgan
Thanks for the link. I think it sent me in the right direction.
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Old 24th Jun 2017, 06:05
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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.
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Old 24th Jun 2017, 06:07
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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.
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Old 25th Jun 2017, 00:18
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It's a flight path angle on the EJet PFD. Not a Vector.

And the pitch attitudes are in the QRH
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Old 25th Jun 2017, 00:24
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Those who need the QRH to know their pitch attitudes have bigger problems than an FPA indication.
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Old 25th Jun 2017, 06:37
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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.
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Old 25th Jun 2017, 09:00
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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!
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Old 25th Jun 2017, 12:20
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Perhaps at the Embraer factory. Thankfully Boeing and Airbus still know what they're doing.
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Old 25th Jun 2017, 16:49
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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?
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Old 25th Jun 2017, 17:40
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Experience, my brother, experience.
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Old 25th Jun 2017, 17:41
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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...
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Old 25th Jun 2017, 17:52
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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.
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Old 25th Jun 2017, 18:06
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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.
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Old 25th Jun 2017, 20:00
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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.
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Old 25th Jun 2017, 20:34
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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.
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