Jawed
Topic Author
Posts: 312
Joined: Mon Sep 18, 2006 10:47 am

Thrust Levers Out Of Sync In Picture?

Sat Nov 18, 2006 2:25 pm

In this cockpit photo:

http://www.airliners.net/open.file?id=0943177

the two thrust levers for the engines are slightly offset, with the left one being pushed forward more. does that mean that the left engine was giving more thrust during this flight? why would that happen?

[Edited 2006-11-18 06:28:01]
 
Ralgha
Posts: 1589
Joined: Tue Nov 09, 1999 6:20 pm

RE: Thrust Levers Out Of Sync In Picture?

Sat Nov 18, 2006 2:58 pm

No it means that the thrust lever calibrations do not match each other. Quite common.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
 
kaddyuk
Posts: 3697
Joined: Thu Nov 08, 2001 1:04 am

RE: Thrust Levers Out Of Sync In Picture?

Sat Nov 18, 2006 4:00 pm

Quoting Ralgha (Reply 1):
No it means that the thrust lever calibrations do not match each other. Quite common.

Throttle Stagger shouldn't occour on the B767 because it has FADEC...
Whoever said "laughter is the best medicine" never had Gonorrhea
 
troubleshooter
Posts: 420
Joined: Mon Feb 07, 2005 5:22 am

RE: Thrust Levers Out Of Sync In Picture?

Sat Nov 18, 2006 4:16 pm

Quoting Jawed (Thread starter):
does that mean that the left engine was giving more thrust during this flight?

If you have a closer look to that picture you will see a N1 indication of 93,5% per engine so the thrust should be equal.
This job sucks!!! I love this job!!!
 
fr8mech
Posts: 6595
Joined: Mon Sep 26, 2005 9:00 am

RE: Thrust Levers Out Of Sync In Picture?

Sat Nov 18, 2006 4:28 pm

Quoting Kaddyuk (Reply 2):
Throttle Stagger shouldn't occour on the B767 because it has FADEC

I've worked on plenty of B767 that were not FADEC. I don't know if this one is or not. But EICAS shows the same thrust being produced (N1).
When seconds count...the police are minutes away.
 
AJ
Posts: 2295
Joined: Wed Nov 03, 1999 3:54 pm

RE: Thrust Levers Out Of Sync In Picture?

Sat Nov 18, 2006 5:58 pm

Quoting Kaddyuk (Reply 2):
Throttle Stagger shouldn't occour on the B767 because it has FADEC...

Only one of our 20+ 767s has FADEC! That split is nothing compared to the good old JT9Ds on the 762s.
 
erj-145mech
Posts: 305
Joined: Tue Oct 02, 2001 4:21 am

RE: Thrust Levers Out Of Sync In Picture?

Sat Nov 18, 2006 8:47 pm

Less than 1/2 knob difference= in tolerance.
 
MD11Fanatic
Posts: 80
Joined: Wed Oct 25, 2006 2:54 am

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 3:39 am

What about the altimeters? The primary and backup altimeters have the same barometer setting but they're separated by 300 ft. What gives?
 
boeingfixer
Posts: 573
Joined: Fri Jul 29, 2005 2:02 am

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 3:59 am

Quoting MD11Fanatic (Reply 7):
What about the altimeters? The primary and backup altimeters have the same barometer setting but they're separated by 300 ft. What gives?

That's common for the Pneumatic Standby Altimeter. It's called Hysteresis and is a mechanical phenomenon where the elastic properties of the bellows and mechanisms inside the altimeter produce errors. This happens after a fast ascent or descent and can also happen after a prolonged period in cruise at altitude.

Cheers,

John
Cheers, John YYC
 
113312
Posts: 580
Joined: Sat Apr 16, 2005 9:09 am

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 4:05 am

Looking closely at the engine indications, the two engines are operating at nearly identical settings. The thrust lever stagger is typical.

The standby barometric altimeter is 300 feet higher than the captains indicator. However, this is also common. The Captain and First Officer altimeters are driven from their respective Air Data Computers and are highly accurrate. This degree of difference is common at that altitude.
 
User avatar
Jetlagged
Posts: 2562
Joined: Sun Jan 23, 2005 3:00 pm

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 4:21 am

Quoting 113312 (Reply 9):
The standby barometric altimeter is 300 feet higher than the captains indicator. However, this is also common. The Captain and First Officer altimeters are driven from their respective Air Data Computers and are highly accurrate. This degree of difference is common at that altitude.

The ADC increases accuracy by applying correction for static port position errors. The standby altimeter has no position error correction.
The glass isn't half empty, or half full, it's twice as big as it needs to be.
 
ZBBYLW
Posts: 1612
Joined: Wed Nov 01, 2006 8:17 am

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 7:06 am

I remember back in the good old days, i was flying in an AC 742 YYZ-YVR and i went into the cockpit and not one of the trust leavers matched, it was interesting to see for sure, another interesting thing about that flight is it was the first time i landed on 30 in YVR in a widebody come to think of it i dont even remember another time where i have seen a widebody land on 30 or 12... o well.
Keep the shinny side up!
 
avt007
Posts: 1989
Joined: Mon Jul 10, 2000 4:51 am

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 7:34 am

I came back from YYZ the other day, and much to my surprise we landed on rwy12, in a 767. It was a very windy day, however.
 
zvocio79
Posts: 165
Joined: Mon Nov 06, 2006 11:33 am

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 7:37 am

different part number............just kidding.........perhaps the triming.........look on eicas, the thrust ratin seems ot be the same for both.
 
Dougloid
Posts: 7248
Joined: Tue Jul 05, 2005 2:44 am

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 7:41 am

Rigging power and speed set levers was pretty common practice on Garretts and PT6s. ....half a knob mismatch was considered pretty decent rigging.

The important thing was to get the decay rate the same on both engines. See, slapping the power levers back on the stops would set up a 700 fpm descent. If the engines did not spool down at the same rate this could cause a lot of heartache, particularly if it was something close coupled with a rapid roll rate like a MU2. That killed more than one pilot.
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn
 
User avatar
HAWK21M
Posts: 29867
Joined: Fri Jan 05, 2001 10:05 pm

RE: Thrust Levers Out Of Sync In Picture?

Sun Nov 19, 2006 6:57 pm

Quoting Zvocio79 (Reply 13):
different part number............just kidding.........perhaps the triming.........look on eicas, the thrust ratin seems ot be the same for both

The EEC would help preventing overboost.
regds
MEL
I may not win often, but I damn well never lose!!! ;)

Who is online

Users browsing this forum: No registered users and 29 guests