737-700 model question.....

mtsu_av8er said:
Brings up a GREAT question!

So, on the 170/175, if you override the autothrottles, you'll get the appropriate annunciation, which is fine. But, the autothrottles will ALSO fight you (not much, but enough that you can feel/hear them). Once you remove your pressure, they will go in the other direction. So, you're slowing to 150 from 190. The autothrottles don't go quite to idle, and you override them. The speed gets down to about 155, you release the pressure. The throttles may go full power, and bump the speed to 170, and THEN go to idle to play catch-up.

I just turn them off, slow, and then re-engage them if that's the scenario . . . :D

It's a Sierra Nevada inspired scenario, though. YMMV.
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I found a great technique not to override the throttles and not turn them off, but I forgot it.

Although, if I remember right, they also have some logic for pressurization and spool time incorporated as well.

The early loads were either fast all the time and sucked in cruise, or slow all the time which sucked for approach.

Sorry...long time ago holmes.
 
mtsu_av8er said:
Brings up a GREAT question!

So, on the 170/175, if you override the autothrottles, you'll get the appropriate annunciation, which is fine. But, the autothrottles will ALSO fight you (not much, but enough that you can feel/hear them). Once you remove your pressure, they will go in the other direction. So, you're slowing to 150 from 190. The autothrottles don't go quite to idle, and you override them. The speed gets down to about 155, you release the pressure. The throttles may go full power, and bump the speed to 170, and THEN go to idle to play catch-up.

I just turn them off, slow, and then re-engage them if that's the scenario . . . :D

It's a Sierra Nevada inspired scenario, though. YMMV.
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I do the same thing.

I also have not landed with them on in more than a year. I think it is much easier with them off than having to override them. I also think it is much easier to get a smooth landing at the targeted touchdown point when my own hand is pulling off the power.
 
Cptnchia said:
While you are right that ATL only goes to IIIb, there is a chart for less than 600 RVR, so you could still taxi in. Plus, there's always the "Follow Me" truck.


9R in ATL. And my bad, I was talking about CAT III, not IIIc specifically.
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You know, I complete misread my 600RVR charts (all of them!) to being between 1200 and 600, not LESS than 600. Good thing I haven't needed that since I upgraded and actually was responsible for that stuff. Doh!

I've always wanted to request a follow me truck. Never had the need though.

On the note of autothrottles, and Airbus guy was explaining to me that not only are they a separate system, but that they are linked to the Flight Director (the same way the autopilot is). And because they don't actually move on the Airbus, you can get screwed on a handflown ILS if you dip below the GS with the autopilot on.

The nose is down the plane is accelerating, but the flight director is pitched up to recapture the glideslope. The autothrottles see the upward FD and spool up the engines to "maintain" speed. And then you overspeed the flaps and have to break off the approach. Sounds fun to me.
 
BobDDuck said:
And because they don't actually move on the Airbus, you can get screwed on a handflown ILS if you dip below the GS with the autopilot on.

The nose is down the plane is accelerating, but the flight director is pitched up to recapture the glideslope. The autothrottles see the upward FD and spool up the engines to "maintain" speed. And then you overspeed the flaps and have to break off the approach. Sounds fun to me.
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Did you mean "flight director" there? If not, I'm lost. If they put ATs on the CRJ-200 and linked them to the FD, it would be a huge cluster. Thing oscillates like there's a heroin addict at the controls sometimes just with the AP on during a coupled ILS.
 
kellwolf said:
Did you mean "flight director" there? If not, I'm lost. If they put ATs on the CRJ-200 and linked them to the FD, it would be a huge cluster. Thing oscillates like there's a heroin addict at the controls sometimes just with the AP on during a coupled ILS.
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Err... Yes... I did mean FD. Thanks.
 
kellwolf said:
Did you mean "flight director" there? If not, I'm lost. If they put ATs on the CRJ-200 and linked them to the FD, it would be a huge cluster. Thing oscillates like there's a heroin addict at the controls sometimes just with the AP on during a coupled ILS.
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Autothrottles are not interconnected with the FD. They are involved in flight guidance, but only reference a couple things: either speed or reference power (idle or the carrot you are going for).

I gotta say I have noticed the E175 guys using the AT a lot in the jumpseat. Nothing wrong with turning them off.. in fact at DL if you turn off the AP it's typically expected that you turn off the AT...
 
PeanuckleCRJ said:
Autothrottles are not interconnected with the FD. They are involved in flight guidance, but only reference a couple things: either speed or reference power (idle or the carrot you are going for).

I gotta say I have noticed the E175 guys using the AT a lot in the jumpseat. Nothing wrong with turning them off.. in fact at DL if you turn off the AP it's typically expected that you turn off the AT...
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At Republic it is not expected to turn off the AT with the AP. Its good that you are seeing them fly with it on most of the time b/c that is exactly how they are trained to do it.
 
Kingairer said:
At Republic it is not expected to turn off the AT with the AP. Its good that you are seeing them fly with it on most of the time b/c that is exactly how they are trained to do it.
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Not exactly the best technique, though. It can be easy to get into thrust oscillations with them on while hand flying.
 
PeanuckleCRJ said:
Not exactly the best technique, though. It can be easy to get into thrust oscillations with them on while hand flying.
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That's exactly why I turn them off. I am in the minority, with only about 20-30% of the guys I fly with landing with them off.

The only thing that my company has as far as limitations goes with the throttles, and if I remember correctly it is a manufacturer limitation, is that the throttles must be on for takeoff.

I find that they do a fine job down final approach with the autopilot on because 'one hand knows what the other hand is doing.'

With the autopilot off, just as you said, the throttles are reacting to what your hand is doing on the controls and the slight delay can create a bit of an oscillating pattern. Easy to override, but if I'm going to have to override it at all, I would much rather just have them off and do it myself.

Just the other day, I was pilot monitoring and the other guy was hand flying final with the throttles on, and to adjust for the speed at around 400 feet, they went all the way to idle before spooling back up to around 55% N1. That's not uncommon. Technically, that doesn't even meet stable approach criteria, yet the training department says you should leave them on. So in order to stay within the stable approach criteria, you must occasionally override a system. Waaaaay too complicated! A/P off? Throttles OFF.

The thing that I dislike most though, is the way one pilot I flew with lands. Both hands on the yoke, all the way down final and during flare and touchdown, and the first time he'll touch the throttles is to put reverse thrust in.

His explanation was that, it's just like the Airbus in that it retards the thrust for you. I disagreed as the Airbus calls out when the thrust should be retarded by the pilot and they still have the authority to keep some power in for as long as they see fit. I think it is poor airmanship to fly the entire approach, flare, and touchdown with both hands on the yoke.
 
Some people like to make it hard, some like to keep it easy.
I dont think the hands off/on Throttles (with their AT on or off) is in dispute.
 
peanucklecrj said:
that shows total automation dependence, which is a bad thing. It's a very typical thing for me in the 757/767 to turn off the ap and fd on any visual approach... I turn off the autothrottles at opportune times when i know they will go to extremes and i can do it smoother.

oh, the huge manatee....
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funniest picture ever!
 
BTAcola said:
If you notice on certain 737's, youll notice a "lunge forward and backward" at certain portions during the flight- this is because - as i was told- SWA ops specs does NOT allowed auto throttle- therefore- my conclusion is that SWA does not have autoland.


CAn we get someone from SWA to confrim?
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SWA pilots got trained and approved last year for A/T.
 
I really didn't care for the AT's ont the 170. I personally only liked to use them in cruise and some approaches. However, the company wanted the used and it made some guys nervous if they were turned off. I think some airlines make them into a crutch.

AT's have their place if they are working welll but IMHO it shoudl be pilots discretion.
 
Bandit_Driver said:
I really didn't care for the AT's ont the 170. I personally only liked to use them in cruise and some approaches. However, the company wanted the used and it made some guys nervous if they were turned off. I think some airlines make them into a crutch.

AT's have their place if they are working welll but IMHO it shoudl be pilots discretion.
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It seems crazy to me that all of these people frown so much on NOT using the automation. I guess I must be suicidal flying 19 people behind me on steam instruments with no autopilot.
 
...all this talk of automation, what do you airline types thing about hand flying?

A guy on another site, a captain said that he strongly discourages hand flying on his flight deck, he states that it isn't professional, or safe. That the automation can fly the plane smoother, and better than people.

He said at the major airline level everyone knows that you can fly so it makes no sense to show off (as it were) that you can hand fly to the flight levels.

He also said that hand flying an Airbus is stupid because the controls and feel don't feel real like you're hand flying. Just sending electronic signals to a box that then tells the controls what it thinks that you want to do.

Opinions?
 
Maximillian_Jenius said:
Opinions?
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The guy's a tool. It's about proficiency, not showing off. That comment makes me think that the guy is a weak flyer and relies on the automation too much. He may discourge it, but if it was my leg, I'd still handfly and then we could go to the CPs office and he can explain why I am dangerous.

Was going into ATL a few months ago. was given a high, tight, short approach at the last minute that required a diving, 180 turn to the LOC. There is no way to mash buttons fast enough to get the A/P to do it. You have to disengage and hand fly it, which is what I did. Once on the ground, the captain made the comment that there are too many FOs who won't hand fly, because they were taught at the regional level to rely on the automation and never touch the contols. He was suprised that I didn't even mess with george.

Remember, the first rule is to AVIATE. That means taking control and flying your airplane.

And you can tell that guy he is a tool.
 
Maximillian_Jenius said:
...all this talk of automation, what do you airline types thing about hand flying?
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There are times where hand flying is definitely more effective than automation. As the previous poster said, there's no way to roll into a tight visual by mashing buttons. Another case that comes to mind is a departure or arrival while picking your way through CBs.

Personally departing out of EWR after a turn or two I like to turn the autopilot on. Personally I feel increased SA is more important than practicing my climbs (which IMO require little skill). We get plenty of radio calls, doing checklists, some guys like to do our ice tests during this really busy times as well. Additionally on shorter flights the pilot monitoring seems to launch right into getting into their arrival by getting ACARS messages and bugging speeds. So...makes no sense to have one guy hand flying while the other is totally out of the loop and not monitoring anything.
 
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