Probably because it doesn't use the iFly flight model ;-).

Is there a video somewhere of a real 747 descending in idle mode where I can see on the PFD the pitch and the v/s?

Thanks

Ghiom

I've seen some for the 777. Can't imagine the 747 would be much different. From what I've read and seen, pretty normal to see around 2500-3000 ft/min on descent initially with a couple degrees nose down at 0.82-85. Exactly what I've discovered the iFly has. By looking at the vid, I saw in descent around 1200-1400. I'd maybe doubt the accuracy of its FDE.

 

 

Mark L.

I'd maybe doubt the accuracy of its FDE.

 

I'll have to tell our 10,000 hour 747 Training Captain  :smile:

 

Looking back it was a relatively gentle initial descent -- I'm not entirely sure why on that particular occasion, there may have been something funky going on with the weather or we may have been particularly heavy, I don't recall.

 

However, on the whole PSX flies very much by the numbers. Some more videos on this subject (produced by said 747 TC) which may be of interest to those following this thread:

 

Descent planning:

747 VNAV descent:

Landing: 

Rick,

 

Thank you so much! This is exactly what I was looking for; a general Guide. It's a type of flying that has mystified me in the past, but with your Guide, I'm excited to give it a go one more time.

 

One thing... most of the big birds I have don't have a functional FMS, however I do have a couple that have Garrett Smith's FMC. Is this sufficient to input STARS/SIDS, or do I meed a 3rd party add on? Also, for the ones that don't... I could enter Waypoints into the FS9 Flight Planner and effectively 'create' a Flight Plan, right?

 

(of course, I guess I could load Garrett's FMS into all of them, or go online and get a .pln from a website...)   :wink:

 

Alan  :smile:

Greetings Alan,

Thanks for the comments. You can use Smith's or the FS9 to create them with some editing. You can even fly some of the SIDs and STARs the old school way as I did by using nav aids if the procedures are based on them. PFPX is a good tool that can include SID/STARs in the FS9 flight plan itself with minor edit.

I'll have to tell our 10,000 hour 747 Training Captain  :smile:

 

Looking back it was a relatively gentle initial descent -- I'm not entirely sure why on that particular occasion, there may have been something funky going on with the weather or we may have been particularly heavy, I don't recall.

 

However, on the whole PSX flies very much by the numbers. Some more videos on this subject (produced by said 747 TC) which may be of interest to those following this thread:

 

Descent planning:

747 VNAV descent:

Landing: 

Actually, to be honest, I gave the Ifly 747 a shake down against real world numbers. Amazingly, it was right on against the numbers. I posted the flight tests in their support forum, so have a look. What I did notice about the flight model is that it does not stall properly in certain configurations. It will stall 20 to 50 knots below the real stall speed for specific gross weights.

 

 

Actually, to be honest, I gave the Ifly 747 a shake down against real world numbers. Amazingly, it was right on against the numbers. I posted the flight tests in their support forum, so have a look. What I did notice about the flight model is that it does not stall properly in certain configurations. It will stall 20 to 50 knots below the real stall speed for specific gross weights.

 

Interesting, I will have a look -- out of curiosity what engine variant did you use for your tests? Certainly 14 minutes to FL340 at MTOW is not in line with the real thing, but maybe it's just an issue with the RR variant.

Hmm, i can't remember. I did a quick check of the aircraft against the QRH performance section. I climb to 40,000 feet getting there at 550,000 pounds. The speed, pitch and N1s were right on the money. I was amazed myself. The approach pitch was right on too. I didn't time the climb, i was more interested to see if the performance numbers at cruise matched up. They seem to have gotten the lift and drag right, but as i stated, the stall and stall warning happens too late.

I may be wrong, but I think before SP1a, it did climb too quick. Seems to have been fixed but like Rick, I haven't timed it.

 

Going back to the descent, if I've read the QRH correct, at idle thrust from FL350 at 250T using 0.84/290, V/S should be -3400 ft/min and pitch -2.0. I recall seeing similar initial descent rates. When I get the chance I'll check out the climb performance.

 

Apart from maybe that question mark, the iFly 747 is stunningly accurate.

 

 

Mark L.