The 777 AT will engage in IDLE and move to idle automatically at 25ft radio altitude, even during a manual (AP off) landing, yes.

 

@ Moekarout.

What your freinds have told you is correct and how most Airlines operate.

However, dont forget that those are company procedures!

Not BOEING Limitations.

Companies can require their pilots to do all kinds of things (for instance, not flying more then 250kt below 10.000ft even if ATC asks you to do so) but that does not mean they are required (as in must/shall) by Boeing.

 

I think we should generaly stick to Boeing procedure here and everyone here can then create his own "company" procedure that he/she thinks are safe.

That does not mean that Emirates and other company procedures are not interesting to learn from, but we must be carefull here that we dont confuse must/shall company procedures and things that can be done (or cant) with the 777.

 

So if Emirates tell you the AP must be engaged during bad weather (thats vague by the way) that does not mean the 777 cant be flown manual in "bad weather" or that Boeing recommends against doeing so.

And if Emirates tells you that the AT must be engaged during TO, it does not mean you can not TO without AT (if it is defective you can still fly and set TO thrust/climb thrust, etc)

 

I dont know the 747, but if AT is not recommended during manual flight for that aircraft by BOEING, then I bet the system behind the AT is different.

The 737 I am familiar with would not do it either.

 

EDIT: oh, while typing the above, I see Machine 2035 has answered the 747 question, good :-)

Would be interesting to know if the 747-8 has the same

Policy as the T7 regarding A/T

 

On the 744 use of A/T depends on company SOP, it's true that with the middle east

Carriers you 'must' use the A/T on the 777, I have a feeling part of the logic is to do with

The FBW and trimming on these newer aircraft when hand flying.

 

On the A3xx auto thrust use is also down to company SOP, it flys beautifully with manual thrust.

 

As far as flightsimming goes, I want to hand fly with manual thrust as much as possible, we don't have airline execs breathing down are necks

 

In the aviation world, the real one, I always had a feeling that everything goes by aircraft manuals and manufacturer rules, but when i met those people who flies every day, i was shocked by the amount of company recommendation or SOP'S sometimes its dif than the manufacturer it self, for example at MEA (middle east airlines) Airbus restricts the max crosswind speed as i recall to 37knots while the company SOP'S restricts that to 33 knots

 

Also, as they said, Airbus doesnt recommend a smooth landing or in other words (float) they recommend to hit the aircraft on its main gear i dont mean crash it, just hit it and let spoilers do the job,,, specially with the A320, they say sometimes they feel its more like a bicycle, its really light and easy to flare! sometimes they flare it; it rotates! :blink: 

 

some pilots in that airline like to land with reverse thrust on idle or full reverse, company gives them the choice, they prefer to hit more on the brakes than damaging the engines with a reverse! 

 

A lot of company SOPS makes it dif to give an identical rules to many segments of flight, but there are certain things that Airbus or others restricts rather than recommends therefore that should be followed! 

The 777 AT will engage in IDLE and move to idle automatically at 25ft radio altitude, even during a manual (AP off) landing, yes.

 

@ Moekarout.

What your freinds have told you is correct and how most Airlines operate.

However, dont forget that those are company procedures!

Not BOEING Limitations.

Companies can require their pilots to do all kinds of things (for instance, not flying more then 250kt below 10.000ft even if ATC asks you to do so) but that does not mean they are required (as in must/shall) by Boeing.

 

I think we should generaly stick to Boeing procedure here and everyone here can then create his own "company" procedure that he/she thinks are safe.

That does not mean that Emirates and other company procedures are not interesting to learn from, but we must be carefull here that we dont confuse must/shall company procedures and things that can be done (or cant) with the 777.

 

So if Emirates tell you the AP must be engaged during bad weather (thats vague by the way) that does not mean the 777 cant be flown manual in "bad weather" or that Boeing recommends against doeing so.

And if Emirates tells you that the AT must be engaged during TO, it does not mean you can not TO without AT (if it is defective you can still fly and set TO thrust/climb thrust, etc)

 

I dont know the 747, but if AT is not recommended during manual flight for that aircraft by BOEING, then I bet the system behind the AT is different.

The 737 I am familiar with would not do it either.

 

EDIT: oh, while typing the above, I see Machine 2035 has answered the 747 question, good :-)

 

Exactly, see my previous comment, companies have alot of DIF policies, the best example is landing lights policies, even though its recommended at 10,000 but alot changes this rule, 

 

some failures in some companies requires the pilot to terminate the flight, some companies carry on in the flight, it really differs from one airline to another though 

 

sometimes not only company SOP, it might be AIRPORT PROCEDURES NO? 

I'll probably disconnect the AT anyways, I've gotten really addicted to hand flight. 

 

I am not familiar with the 777, but I believe the recommended SOP is to NEVER disconnect the AT when manually flying any approach. If you like to hand fly the whole hog, you can try the below "technique" by deselecting the active A/T mode (is it similar to SPEED in the 737? Can any beta tester or 777 pilot clarify this?), if possible. There is no SPEED button on the MCP in the 777, like there is on the 737. There is only an A/T button, IIRC. Once again, I am not familiar with the 777, just applying a 737 technique here.

 

On the 737, no need to disconnect the AT to manually control thrust(speed) for landing. Just deselect speed on the MCP and manually control thrust. The MCP SPD annunciation will disappear, to be replaced by ARM. That way, in case of a Go Around, when you hit TOGA, the AT will advance the thrust to the commanded GA thrust. More importantly, you also have low speed protection available with the AT in ARM. If you hit TOGA and the AT is disconnected, then you will only get the AFDS guidance for GA without the required thrust, putting the aircraft into a potentially dangerous approach to stall situation.

 

I think there is a BIG difference in the usage of the terms Disconnect and Disengage when it comes to the context of the AT. One has to be vary of what your intentions are.

 

 

Regards,

 

 

Dinshaw Parakh

A lot of operational procedures are SOP, based on manufacturer recommendations. All must be certified though. Breaking SOP in many companies can be a sackable offence.

 

Whether you can land with auto-throttle on or not is simply down to how quickly the auto-throttle can respond to speed changes as the result of pilot input. It's also a question of comfort. The AT may or may not be smoother than a pilot - that is determined by the pilot in question.

 

Whilst the use of AP may be recommended in turbulence (reduce pilot workload which is why it exists), it may be better to disengage the AT so the throttles are not hunting speed all the time. The pilot can watch the overall speed trend, and make small adjustments to correct (trim, wait, trim, wait, trim...). This is more pleasant for the passengers.

 

Best regards,

Robin.

I am not familiar with the 777, but I believe the recommended SOP is to NEVER disconnect the AT when manually flying any approach.

The keyword is recommended. Just because Boeing recommend it doesn't mean a pilot will be reprimanded in the case that he did disconnect the A/T.

 

Anyway IIRC, it is SOP to leave the A/T switches in the ARM position (the two switches L and R).

 

More importantly, you also have low speed protection available with the AT in ARM. If you hit TOGA and the AT is disconnected, then you will only get the AFDS guidance for GA without the required thrust, putting the aircraft into a potentially dangerous approach to stall situation.

 

The T7 also has protections when A/T is armed but not actived. For example with the autothrottle armed, the autothrottle automatically activates if no autopilot

or F/D is active or an autopilot or F/D is in VNAV XXX, ALT, V/S, or G/S, and:

• speed less than an FMC calculated value for one second

• thrust below reference thrust

• airplane altitude above 100 feet RA on approach, or airplane barometric altitude 400 feet above airport on takeoff

 

The autothrottle can support stall protection when armed and not activated. If speed decreases to near stick shaker activation, the autothrottle automatically activates in the appropriate mode (SPD or THR REF) and advances thrust to maintain minimum maneuvering speed (approximately the top of the amber band) or the speed set in the mode control speed window, whichever is greater. The EICAS message AIRSPEED LOW displays.

Companies can require their pilots to do all kinds of things (for instance, not flying more then 250kt below 10.000ft even if ATC asks you to do so)

 

Company policy can overrule "in flight" ATC instructions??

Company policy can overrule in flight ATC instructions??

Company policy can overrule "in flight" ATC instructions??

No, quite a few errors in his post so I would be careful about what you take as fact.

 

Regards

Yeah, its not rocket science that disobeying ATC instructions isn't going to end well.

What ATC can suggest is "ABC123 Descend FL050, no speed restricition."

After which, you still trot along merrily while maintaining 250 below FL100. There is no harm in doing so, and no rule has been broken.

If ATC suggests "ABC123 Descend FL050, maintain 280 or more.", and you decide to fly 250 while having acknowledged the instruction, you'll have some explaining to do. You can always try "Unable speed, ABC123.", but most controllers will ask for a reason.

On the contrary - flying at 250 kts or slower could be less efficient than accelerating to e.g. 300 kts, so not accelerating can burn more fuel, and increase flight time (both cost $$$ to the company), so any shortcuts/advantages you can get from ATC are very welcome indeed.

 

Best regards,

Robin.

 

 

No, quite a few errors in his post so I would be careful about what you take as fact.

 

Don't worry. I certainly wasn't taking that part as fact. I added two question marks to illustrate my scepticism :smile:

 

 

Company policy can overrule "in flight" ATC instructions??

 

You know the magic word. Unable.

@Robin:

 

If I had a nickle for every time I read something completely inefficient and illogical in SOPs... Well, I wouldn't be able to buy the 777 the way it's priced now, but I'd come close to the Suspected Price ;-)

No, quite a few errors in his post so I would be careful about what you take as fact.

Regards

I dont know what your credentials are, but this thread is doing pretty well, I can assure you!

 

In every thread I read there are mistakes and unaccuracies, you want to close all of them down?

This is a hobby here and most are not profecionals and as long as everyone has an open mind, I think most discussions are fun and interesting.

 

I am impressed by the overal knowledge here and all other 777 threads by the way!

 

If you are going to say, things are not correct, then at least name them so we can discuss things further and correct them if necessary.

How should a hobby simmer identify what is correct and not from your (pro?) comment?

 

So far pretty much everybody has agreed that company procedures and BOEING recommendations are two different things.

Various examples of SOP have been mentioned that confirm that you CAN fly the 777 manual with the AT off or engaged (up to the pilot) but that BOEING recommends it to be engaged.

 

If ATC gives you instructions that are not considered save by SOP or not considered save by you (the pilot) under the present circumstances than YES you can and should tell ATC "unable"!

This could lead to you getting a delay vector or so, but you dont have to do anything against SOP.

ATC is not a one way street, they are also there to help you!

Also SOP of course take ATC requirements into consideration, so they will not contradict onanother very often.

 

What you can not do is accept an ATC clearance and then do the opposite.

But I did not say that, did I.

I dont fly for Emirates, so I dont know if they have an SOP that sais max 250kt below FL100, I only heard such a rumour.

Don't worry. I certainly wasn't taking that part as fact. I added two question marks to illustrate my scepticism :smile:

One question mark and one less smart remark would have been enough.

I would have explained the same as above.

 

Scepticism and questioning things is fine.

And everybody can and should do that.

To say something is totaly wrong/not factional you'd better know what you are talking about.

You know the magic word. Unable.

Thank You

No offence intended, Rob. I would have thought that ATC instructions should be followed to the letter, but I am quite happy to be proved wrong.