What are some real world descent speeds? I can't imagine a 777 really goes down the econ recommended 268 knots. Probably same as other types, 280, 290,300 around?

Hi 

 

In my Company we use a cost index of 6, this gives us a descent speed of 250kts, that's on a 737-300. 

 

Regards

 

Shifty

I have said this before on another thread a few days ago.

 

ECON speed is not a fixed speed.

enter a high CI and your ECON climb and descend speeds will be higher than with a low CI.

 

Any descend speed ECON spits out can be an actual used speeds by airlines.

Sometimes with a low CI we have 250kt - 260kt during descend.

Boring, yes, I hate it!

But if it saves money....

Thanks god sometimes the controller will ask you to speed up a bit and then you must right :-)

 

I find 280kt a good compromise.

Not slow, and also leaves you a bit of headroom in case Vnav needs to pitch down a bit more to stay on its calculated path (causing the speed to increase beyond the 280kt target).

I use a cost index of 66 which I think gives around 280-290, need to double check though. I believe 66 is used by some airlines.

I've heard of simmers having problems to slow down and descend at the same time (who would not have those problems in that kind of a situation :lol:). Heading towards the 10k/250 kts limit at 310 kts descent speed certainly won't help those folks ... In the drag-low, wings-highly-efficient T7 it seems even more important to be slower during your descent already ... Just my two layman's cents.

I've heard of simmers having problems to slow down and descend at the same time (who would not have those problems in that kind of a situation :lol:). Heading towards the 10k/250 kts limit at 310 kts descent speed certainly won't help those folks ... In the drag-low, wings-highly-efficient T7 it seems even more important to be slower during your descent already ... Just my two layman's cents.

Speedbrakes help. Pretty much every real-world 777 flight I have been on (many), they always use a bit of speedbrake, sometimes more than usual.

I use a CI of 80, that gives me a nice calm but sane 289 kts, which is also not far from the turbulence penetration speed.

.84/310/250 always worked for me. :hi:

I'm a fan of .84/320 in smooth air. If we're going into somewhere that's stormy or just has a bunch of CAT - I like .82/280. 

I feel like just for one day, simmers across the land should just take a moment and trust the wisdom of the people who've handed them something.

 

I know that there have been some pretty shoddy products out there that can't quite be flown by the books, but when your product ships with Boeing FCOMs, FCTMs and other official documentation, you can be reasonably sure that the plane was developed to a high standard.

 

As such, the persistent doubt isn't quite necessary.  I understand it, to a certain degree, but at the same time, it's hard not to laugh when I read the "I find it hard to believe that [x]," comments (or the "is the CAM actually in the real aircraft???").

 

I really wish I still had my IAD SIDA badge.  I'd give people field trips, and this would be a daily occurrence:

 

• The logo lights are actually just like that, huh?
• The Unitedental really started both engines in the push and AmeriAirways only started one?  I thought they all did it the same way!
• What did that controller just say?  "Cleared for the visual???" But Dulles has ILS approaches!!!
• I read online that Unitedental uses a CI of 23.  This FMC says the flight is going on a CI of 57!!!
• ...and the dispatch sheet for the later flight has a CI of 10!!!
• That SWA plane turned his taxi light on immediately after the push and left it on, but the Unitedental plane only turned his on when moving!

PMDG doesn't just make things up as they go along.

 

 

"Cleared for the visual???"

 

What's a visual??!?

What's a visual??!?

More fun!

 

You can be anywhere when ATC asks you "do you have the field in sights"

For instance on downwind.

If you answere "yes", ATC can clear you for a visual approach.

Separation to other aircraft is then the pilots responsibility (under radar vectors it is ATCs responsibility) .

You then maneuver the aircraft onto final as you see fit (within reason) and await the landing clearance on final.

You fly towards the runway by looking out the window and judging if you height versus distance is correct.

So, no LOC/GS or any approach aid is used (but you can use them if you need help :-))

More fun!

 

You can be anywhere when ATC asks you "do you have the field in sights"

For instance on downwind.

If you answere "yes", ATC can clear you for a visual approach.

Separation to other aircraft is then the pilots responsibility (under radar vectors it is ATCs responsibility) .

You then maneuver the aircraft onto final as you see fit (within reason) and await the landing clearance on final.

You fly towards the runway by looking out the window and judging if you height versus distance is correct.

So, no LOC/GS or any approach aid is used (but you can use them if you need help :-))

 

I think he was being facetious, but to clarify a little more:

 

• The pilot is also encouraged to pre-emptively report the field in sight when he or she sees it.  You might not get the approach cleared immediately, but it saves ATC from having to ask.
• Separation in the United States becomes pilot responsibility after reporting other traffic in sight, not through clearance for the visual (the more detailed answer would be separation is the responsibility of ATC at all times under IFR, unless traffic has been called in sight).  I think in the UK, that still doesn't absolve the controller of standard radar separation for whatever odd reasons (not to say the FAA doesn't have its own oddities).
• Many airlines actually have an SOP such that the crew should have the LOC tuned if it's available.  This aids in proper tracking (vertically and horizontally), and ATC (in the US, anyway) will often string aircraft on the LOC even on visuals:

  "Fly heading 340, join the runway 1C localizer, report the field in sight."