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Auto Throttles.

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Auto Throttles.

Old 2nd Mar 2009, 19:50
  #81 (permalink)  
 
Join Date: Mar 2001
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I have to agree there, it is not about the plane and the automatics that come with it. It is more a question about attitude towards your job and flying in general. And quite often it is a big question about the attitude of management pilots who define how the planes have to be operated in a certain company.

In the outfit i flew in for the last 8 years it was encouraged to do raw data no-automatic approaches and departures and raw data manual flying was part of every SIM exercise, including of course raw data manual one engine out flying. Of course you could spot the difference between those that often switched it off and those that did not. Never had a problem there, but then i started flying at the age of 12 in glider planes.
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Old 2nd Mar 2009, 21:11
  #82 (permalink)  
 
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If you don't mind a non-pro asking a question...

Do any companies require pilots to fly manually on the line on any kind of regular basis for precisely the reason Alpagueur320 gives? Or is it entirely at the captain's discretion? Could you always fly with automatics with obvious exception of take-off and disconnect for landing?

Also, if the throttles do not move on the Airbus when the A/T is engaged, when you disconnect them does N1 not "jump" to the thrust indicated by the manual position of the levers? Hope that question makes sense.
Our Ops Manual (UK low cost) says that you should make full use of the automatics where apropriate but equally should maintain manual flying skills.

To disconnect the autothrust on an airbus you can either line up the thrust lever position indicator with the curent thrust and then disconnect or else close the thrust levers (this will disconnect the autothrust) and then put them quickly to the desired thrust position before the engines have a chance to spool down.
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Old 2nd Mar 2009, 23:07
  #83 (permalink)  
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I'm curious why Airbus elected to go with non-moving throttles while in auto, vs moving. What is the logic? I didn't like the description of the transfer from auto to manual thrust.
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Old 2nd Mar 2009, 23:43
  #84 (permalink)  
 
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Airbus thought they weren't necessary. At first, on the 'bus, I was sceptical. But after several thousand hours, I'm in agreement. The levers are technically a switch. You move them into the detent of the thrust regulation required, and the fact they don't move when you press a button is inconsequential. In fact, setting your thrust limit by moving a lever in the correct sense is more logical than pressing a button. (I only ever found one pilot who could explain that Boeing THR button adequately!)

And when want to use the thrust manually, they become regular thrust levers.


But the best autothrust system I've ever used was on the VC10. The Flight Engineer had his own set of thrust levers on his desk and would set the thrust, or fly a speed that you asked for. And it was proactive. On a check ride, you briefed the engineer to give you the setting you needed, which wasn't necessarily the one you asked for! The only snag was that the systrem was expensive. Some of the FEs could drink a lot of beer!
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Old 2nd Mar 2009, 23:44
  #85 (permalink)  
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Sounds like a good system on the L-1011. And yes.....ah, Lockheed. I only have experience in the 'better' Lockheeds tho...Connie and Electra!

I'd still like someone to respond on the Airbus system.
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Old 2nd Mar 2009, 23:46
  #86 (permalink)  
 
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Ok, a astute observation about autothrust...and of course it is on the L1011.
On this airplane, two channels of autothrust, with (as I recall, eight accelerometers )for each channel, both channels active during automatic approach/land (autoland) ops.
The autothrust system is very accurate, especially during windshear occurances.
Sometimes...you might see Vref+40 on appraoch, at 800agl, yet it unfailingly reduces to Vref +10, crossing the fence.

IE: the GOLD standard.
It will provide the proper thrust for all situations during approach....much better than any pilot could.
Even...411A.
Lockheed...simply built to a higher standard.
Over thirty years ago.

Ahhhh, Lockheed!!

PS: One of the reasons that the L1011 autothrust is so good...the airplane is powered by the three-shaft RollsRoyce RB.211 engine, with its superb acceleration qualities.
RollsRoyce...very good engines.
I kid you not.

PPS: The Conway was superb, as well.
Credit where credit is due.
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Old 2nd Mar 2009, 23:55
  #87 (permalink)  
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Dan Winterland -

OK...thanks for that. I still don't like the way EGPFlyer above described the disconnect though.

And...411A...don't know how our posts got mixed up, but.....
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Old 3rd Mar 2009, 01:42
  #88 (permalink)  
 
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Haven't found it a problem, although the closing method isn't recommended in flight at power setting higher than idle - in my manuals anyway. The closing method is primarily for landing. The TLs are closed drung the flare (the "REATRD" call reminds you should you forget! And it's not intended as an insult!!), the AT disconnects as you would expect and want. The only time I (personally) would use it would be to power up manually after a THR IDLE descent.

The reccommended book method is to align the TLs with the AT thrust setting by aligning the TL position indicator on the EPR (V2500) or N1 (CFM56) guage, then presssing the disconnect button. this gives a seamless transition from auto to manual thrust.
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Old 3rd Mar 2009, 01:49
  #89 (permalink)  
 
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And...411A...don't know how our posts got mixed up, but.....
Not to worry, DC-ATE, I edited, then reposted, for additional info.
Yes, the 'ole L1011, although a totally analogue system, is very precise in its operation.
Is it old, and today, labor intensive?
You bet, but still produces the results, as advertised.
Doubt?
Just ask the pilot who has ever flown one.

Similar to the Electra...a pilots airplane.
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Old 3rd Mar 2009, 06:56
  #90 (permalink)  
 
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Yeah I forgot to add that in. I only ever use the TL to idle method if the engines are at idle thrust. I don't actually know why I mentioned it because it wasn't really relevant to the question
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