Autothrottles

jordane93

jordane93

Touchdown! Greaser!
PoA Supporter
Joined
Sep 9, 2013
Messages
10,663
Location
Long Island, NY
Display Name
Display name:
Jordan
Those of you that fly with them, how often do you click it off?
 
jordane93 said:
Those of you that fly with them, how often do you click it off?
Click to expand...
In the 737, 757, or 767 they are clicked off for every non-autoland landing. I believe that they can stay on for landing in the 777 and 787.

I usually click them off when I turn off the autopilot on approach. I usually leave them on while hand-flying on departure though will click them off for low-altitude level-offs, to make a smoother transition to a 250kt level off, and achieve the AIM recommended 500fpm-1500fpm for the last 1000' of the climb so as to avoid unnecessary RAs--something that the VNAV does not do.
 
We leave the 737 autothrottles on for landing (unless we choose not to, of course). We have to add the steady state headwind component plus all of the gust factor to ref if we turn them off, so most of the time we leave them on to keep our speeds down. Some guys turn them off for flaps 40 landings or when it's really gusty, but most (including me) just push through the clutches in those cases.

I've only been on the airplane 9 months and have already have had the autothrottles deferred twice, so I like to click them off when turning off the autopilot every trip or so.
 
Last edited:
On old autopilots you could choose altitude hold or mach hold, but not both simultaneously for obvious reasons. On today's aircraft, is it normal to use autothrottles at cruise to maintain a mach number?
 
JohnAJohnson said:
On old autopilots you could choose altitude hold or mach hold, but not both simultaneously for obvious reasons. On today's aircraft, is it normal to use autothrottles at cruise to maintain a mach number?
Click to expand...
Yes
 
On all the time, company procedure. Oh yea, once in a blue moon I'll turn the auto-thrust off in really nasty turbulence, and just manually set N1 according to the QRH.
 
Last edited:
I have disconnected autothrottles only a handful of times in the Bus (other than check rides).

Every time has been unplanned... ATC turns you tight and slam dunks you. It has truly just been natural reaction to grab the throttles and stick and fly the airplane manually... to make it do what you want it to do.

Honestly, I believe the automation is harder than manual. Less work, but harder.
Does that make sense?
 
JohnAJohnson said:
On old autopilots you could choose altitude hold or mach hold, but not both simultaneously for obvious reasons. On today's aircraft, is it normal to use autothrottles at cruise to maintain a mach number?
Click to expand...

Probably because Mach Hold was a pitch function like it is on my plane. Similar to Flight Level Change I think is what the newer planes call it. I can have mine climb in mach hold with an altitude armed. When it gets there the autothrottles will stay in climb power until I take it out of climb power so you have to be careful of that.

For OP I leave it on until descent. Then I will click them off and slowly creep them back so I can get a nice smooth 1,000 ft./min descent and increase indicated airspeed as the mach goes down and IAS Vne goes up, until I hit our standard descent speed. Then I turn the ATs back on again. Keeps them from going back and forth as I increase the speed bug. Usually turn them off on final approach somewhere too.
 
When you go manual, the airplane does exactly what you want it do, immediately.
 
Interesting. I’m sure you guys have policies when it has to be on and when it has to be off.
 
Gucci Pilot said:
Probably because Mach Hold was a pitch function like it is on my plane. Similar to Flight Level Change I think is what the newer planes call it. I can have mine climb in mach hold with an altitude armed. When it gets there the autothrottles will stay in climb power until I take it out of climb power so you have to be careful of that.

For OP I leave it on until descent. Then I will click them off and slowly creep them back so I can get a nice smooth 1,000 ft./min descent and increase indicated airspeed as the mach goes down and IAS Vne goes up, until I hit our standard descent speed. Then I turn the ATs back on again. Keeps them from going back and forth as I increase the speed bug. Usually turn them off on final approach somewhere too.
Click to expand...
good to see you back Gucci
 
Greg Bockelman said:
Maybe not so obvious. What are the reasons?
Click to expand...

Gucci has it right. Both did their thing via the elevator, and to maintain a mach number to keep an accurate rendezvous time or when intentionally changing altitudes, etc., you had to be willing to sacrifice altitude.
 
When flying manually the auto-thrust stays on. Company discourages manual flying as well.. Basically at about 200 or 300 feet auto-flight on, at minimums auto-flight off.
 
jordane93 said:
Those of you that fly with them, how often do you click it off?
Click to expand...

In the Gulfstream, I tend to leave them off for:

  1. Noise abatement procedures, i.e. Orange County/John Wayne;
  2. certain missed approach procedures (notably Le Bourget, France, which features an initial level-off altitude of 700' MSL to remain clear of De-Gaulle's airspace, and the A/T, if left to its own 'devices,' would violate the crew by climbing right up into the flow);
  3. gusty wind conditions which exceed the ability of the A/T to manage effectively;
  4. crossing restrictions on STARs coincidental with speed restrictions, which the A/T are highly optimistic about achieving with their late power reductions; and
  5. landing. I click them off somewhere between 100-200 feet AGL, generally.
Then, sometimes for the hell of it, I fly with them off for no good reason.

I also fly and remain current in a different type which doesn't feature autothrottles (CL300/350) so it's not that big of a deal to me. To some Gulfstream pilots, however, it damned well better be an emergency to not use the autothrottles in an otherwise normal profile. LOL.
 
jordane93 said:
Those of you that fly with them, how often do you click it off?
Click to expand...

If i'm hand flying the auto throttles are off. If i have to hold them to keep the thrust where i want it (gusty winds on approach) then i turn of the throttles. Basically if the automation is not making my life easier i turn the **** off. When i worked at republic they were big on never turning off the AT, even if hand flying the aircraft. It was a huge pain in the ass. I ignored that particular piece of guidance since it was not written down anywhere in the manuals. I found it irritating to be directing the PNF where to set my speed bugs and what mode i wanted on the throttles while I was hand flying the aircraft, especially since it was normally in the terminal area you would be hand flying and we were both busy. I found it to be more efficient to just fly the whole plane, engines and all, if the AP was off.
 
On the 757 we have to click them off for landing, I generally click them off around 100-200 feet or so. If it’s really windy sometimes I’ll click them off early simply because sometimes it just can’t keep up with what’s going on and what you’re doing, since it doesn’t know your next move, someone once told me think of it as reactive not proactive, but for me usually around 100-200.
 
jordane93 said:
Interesting. I’m sure you guys have policies when it has to be on and when it has to be off.
Click to expand...

Not really. Our manuals dictate how we're supposed to set up for takeoff, and that's with the AT on, so that's what we do. But beyond that they don't really specify anything else, so anything goes. Some guys will get the gear up and immediately turn off the AT and their flight director (assuming we're not on an RNAV departure) and hand fly to altitude like it's a big ass 182. There's nothing in our book that prevents that. Same thing for the approach and landing. Raw data with AP and AT off from around the time we're vectored off the arrival. To be fair, these guys know full well that doing so increases my workload substantially, so they do this only when the conditions are right for it.

Me? I'm simply too lazy for that crap. As are most others. The typical flight has the autothrottles on from takeoff to touchdown. But that's a cultural thing - it's not dictated by our manuals.
 
I fly with it about half the time. But she gets upset if i try to click her off.
 
Kritchlow said:
I have disconnected autothrottles only a handful of times in the Bus (other than check rides).

Every time has been unplanned... ATC turns you tight and slam dunks you. It has truly just been natural reaction to grab the throttles and stick and fly the airplane manually... to make it do what you want it to do.

Honestly, I believe the automation is harder than manual. Less work, but harder.
Does that make sense?
Click to expand...

kritchlow, you will be getting an email from the school house soon stating, "repeat after me the bus has autothrust not autothrottles..." :)
 
kayoh190 said:
Not really. Our manuals dictate how we're supposed to set up for takeoff, and that's with the AT on, so that's what we do. But beyond that they don't really specify anything else, so anything goes. Some guys will get the gear up and immediately turn off the AT and their flight director (assuming we're not on an RNAV departure) and hand fly to altitude like it's a big ass 182. There's nothing in our book that prevents that. Same thing for the approach and landing. Raw data with AP and AT off from around the time we're vectored off the arrival. To be fair, these guys know full well that doing so increases my workload substantially, so they do this only when the conditions are right for it.

Me? I'm simply too lazy for that crap. As are most others. The typical flight has the autothrottles on from takeoff to touchdown. But that's a cultural thing - it's not dictated by our manuals.
Click to expand...
Our latest FOM revision says no more raw data T/Os. Our FD has to up. I’ve maybe only flown with one or two captains that clear the FD for T/O. I’m kind of glad my first jet is a CRJ because it’s not the smartest and I actually have to think sometimes.
 
jordane93 said:
Our latest FOM revision says no more raw data T/Os. Our FD has to up. I’ve maybe only flown with one or two captains that clear the FD for T/O. I’m kind of glad my first jet is a CRJ because it’s not the smartest and I actually have to think sometimes.
Click to expand...

Ours is the same - a few guys will turn off the FD shortly after takeoff. Shutting off the FD in the climb is rare though - the vast majority don’t do this. It’s just nice to see our manual give us the flexability of sharpening our skills while trusting us to know when to fully use the automation that’s available.
 
kayoh190 said:
Ours is the same - a few guys will turn off the FD shortly after takeoff. Shutting off the FD in the climb is rare though - the vast majority don’t do this. It’s just nice to see our manual give us the flexability of sharpening our skills while trusting us to know when to fully use the automation that’s available.
Click to expand...
Speaking of sharpening our skills. My dad sent this to me yesterday. Was this you @EvilEagle ;)

pArJNFc.png
 
unsafervguy said:
kritchlow, you will be getting an email from the school house soon stating, "repeat after me the bus has autothrust not autothrottles..." :)
Click to expand...
Lol!!! I was thinking the same thing as I was typing it, but opted not to confuse the issue.
 
Ryan F. said:
In the Gulfstream, I tend to leave them off for:

  1. Noise abatement procedures, i.e. Orange County/John Wayne
Click to expand...
What G are you flying that you need to fly the noise departure out of SNA? For us we are way above the sensors and never even consider the noise. We are in a falcon and I guess we have better performance but I didn't think a G had trouble climbing out.
 
jordane93 said:
Speaking of sharpening our skills. My dad sent this to me yesterday. Was this you @EvilEagle ;)
Click to expand...
Haha, no wasn't me. I kinda wish it was because if I was flying a DAL jet it must mean I'm retired from the USAF! Soon... soon I'll be back to the good life!
 
Last edited:
NJP_MAN said:
What G are you flying that you need to fly the noise departure out of SNA? For us we are way above the sensors and never even consider the noise. We are in a falcon and I guess we have better performance but I didn't think a G had trouble climbing out.
Click to expand...

We had a crew ring the bell a couple years back and we got fined. It wasn't a huge fine, but not a good look for us.

The performance of a G450 with a full bag of gas isn't nearly as good as a Falcon, so I'd guess that's the reason.
 
jordane93 said:
Our latest FOM revision says no more raw data T/Os. Our FD has to up. I’ve maybe only flown with one or two captains that clear the FD for T/O. I’m kind of glad my first jet is a CRJ because it’s not the smartest and I actually have to think sometimes.
Click to expand...

I suspect a lot of operators are adding that to their SOP/FOM in order to assure compliance with FAA guidance on RNAV-1 procedures (e.g., AC 90-100A). RNAV SIDs and RNAV STARs are RNAV-1 procedures with tighter tolerances (a flight technical error of only .5NM is considered suitable on an RNAV-1 procedure). FAA guidance specifically states that a flight director and/or autopilot should be used.


Sent from my iPhone using Tapatalk Pro
 
jordane93 said:
Those of you that fly with them, how often do you click it off?
Click to expand...

On the DC-10, every time at top of descent.

MD-11, on all the time and pushed thru the clutches when needed.

MD-80 and B-747-400 off prior to landing except auto land in the 747.
 
You must log in or register to reply here.
Back
Top