Does anybody have issue with the B747 turning - whilst trying to maintain altitude with the AP?

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xbox
#SeriesS

I have been flying with the B747 - I confess that I have flown it at full payload and max fuel (to give real feeling of a full flight).

Anyway, when I am on the approach using ILS and some ILS routes have bends.

The AP follows the bends however the plane loses A LOT of alittute to the point where I need to take over and save the plane.

I understand the B747 will not be as agile as an A320 or B737max is at full payload doing certain manoeuvres.

However, this is part of an ILS approach and the B747 (yes at full payload) really struggled.

The AT was on and I expected the AT to kick in and go full throttle (which it did) but was not enough - I have to take over.

Is there a technique or way to deal with this?

I never had this issues before (however I was not flying the B747 at full payload).

But pilots fly B747s and A380s at full payload all the time.

I tried certain flight paths (where the approach is direct and simple).

But not always the case as the options can sometimes be limited.

I tried to make my own custom made approaches using VFR but accuracy not as good.

If it comes to it - i will fly B747 at default payload rather than near max.

Just wondering how people deal with it?

Cheers

2

OK, I missed this post!

One thing to remember, you never load any more fuel than is needed, so you aren’t carrying too much weight when you land.
You only load enough for the flight, then enough for a few missed approaches, add enough to get to your alternate airport, plus a bit more for contingencies.
Use this app for a good estimate.
http://fuelplanner.com/

The important part about slowing down is proper flap management, those positions are indicated on the speed tape as you descend.
The flaps give more lift at lower speeds.
The 747 needs to start to extend flaps to the first position around 260 kts., then steadily extend them further as you get slower.
That should keep you in the air a bit better!

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  1. I get ya about not need more fuel than necessary - HOWEVER - wouldn’t there be a time when the plane get filled up and a pilot(s) will have to fly on a full tank and potentially a full aircraft?

  2. Yes the flaps - do kill the speed down to 250 and go down a flap - however issue is with certain bends by the time it is cleared the runway is 10NM away!!! and to slow down from 250KTS to 150KTS in a plane like the B747 in 10NM not to mention LOC and APP mode - a lot - given its weight.

Hence why I ask - suggested - would it be best to have a different type flight plan. I have seen GPS direct to direct paths (but much longer) however approach to runway is STRAIGHT - NO BENDS and for a plane that is so big and heavy want to limit all these bends(!)

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The only time the tanks would be full would be if needed for the flight distance. By the time they landed that fuel would have burned off.
If you need to slow down that fast, you still need to get flaps down. You will have to start slowing down way in advance.
No, they still fly sharp bends into an approach at times, it depends on the STAR.
If you want to see some awesome examples of 747’s doing this, search on U-tube for 747 Kai Tak.
Here is a link to one.

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Yes I understand that means I am going too fast and need to slow down earlier.

HOWEVER, I was one time flying @ 155KTS (at full load and tank still pretty much full) and it would started falling when turning!

So I know I need to be faster than 155KTS so 200KTS?

Cos, ultimately, need to slow down for that final approach - not wanting to damage the landing gears!

Yes - I know B747s can do turns - but just how I have it so packed - not logically like that.

1 Like
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Quite often they are at full load. Especially the 747’s as that’s the routes they fly, long haul, with fairly full loads, because there isn’t 4 or 5 flights a day as a short haul route.
Fuel is the one thing you want to keep to the required amount.
All airplanes will loose a bit of altitude on a sharp turn to a certain degree.
The faster you are in a turn the wider the turn will be, so start working your way up and find that sweet speed. I wouldn’t think 200, that seems a bit much.
But, that depends on your Vref speed. If that’s say 165, then 200 isn’t that much faster, and if you intercept at say 15 miles out, you can slow down to your approach speed which in that case will probably be around 175, fairly easily.
Good luck!

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Yes I get 747s fly at full load for the long hauls of course.

Yeah A320 i lose lil altitude when turning but nothing serious lol the VS will go into the negatives but then picks up.

But a full decked out B747 full everyhing on final approach is SINKS A LOT - so you advice about flying with the amount of fuel needed - i will do that so when I come to final approach only weight is the cabin and luggage - fuel would have burn off an be practically at 0.

That should help.

In terms of vertical reference speed - well they say 250kts - I mean B747 an B787 an A380 i am not an expert but given their size and weight you’d need a lil speed on landing not FLOATING speed to where it will slump.

175KTS i think would be appropriate for a B747 on a landing approach.

By the time you idle the throttle should go down further to 160KTS (with flaps all the way down).

I will give it a go an let you know - right now flying with AP on for an RNAV will let you know.

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The speed that you are at when you cross the runway threshold is called Vref.
It is just a little bit above your actual touchdown speed, as you will flair and retard the throttle immediately prior to touchdown, which will level you out a bit, and slow you down, thus causing your aircraft to touchdown.
Vref is calculated in the Perf pages of the FMC (MCDU) when setting the aircraft up for final approach, approximately the last five miles out, you should be at about 5 knots above that and slowing down to 2-3 knots above, in order to be at Vref when you cross the threshold.

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Up till SU5, 747/787 were sorely in need of serious work. After that, both are much better. Yes, on both losing altitude but not as bad as before. Still both planes do not fly like their counterparts in FSX or X-Plane, they wallow like pigs to put it bluntly. In FSX way better flight model, have only flown 737 on one hop in XP and it was to make sure I was not losing mind, proved that this game is at fault, not my flying skills. Took out 737, did approach and ILS landing just like the days before MSFS. The vision field in FSX for the 747 is hard to adjust in landing mode, in MSFS it’s way better, as well as XP. Flown too much today, maybe test both tomorrow.

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I didn’t land that RNAV flight - I didn’t put in enough fuel and as a result stressed the B747 lol

Anyway - I just did a long haul flight B747 0.5 fuel tank - left the payload as it default and no issues with the plane when it was turning NONE!

Yes lost a bit of altitude but nothing nuts.

But I will talk going 4ward using the fuel needed and not full tank.

But as the other user said - he seems to notice something about the B747 on MSFS.

Maybe I need to just stay in my lane and not attempt to ‘fly’ with a full payload - UNLESS I know the fuel will near empty coming to arrival.

For now - will stay in my lane hahaha

1 Like
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Interesting.

I mean I am not an expert but I am sure if i spoke to a B747 pilot they would be able to say what the behaviour is of a fully loaded 747 when it is turning and how much altitude it loses etc etc etc etc.

One time I was at 5k feet not far from the runway - it turned and went down by 3.9k feet!!! Was crazy!

Had to save the plane!

Never played plane x or FSX but I take ya word for it!

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That amount of lost altitude is definitely not right.

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All - Plane model in MSFS is not correct, but much improved since SU5. I just took defaults on fuel and payload, maybe need to tweak it some. I practice flying it at PMDY, but when tried several flights I always failed in my attempts to get ILS to work correctly. The tie in between FMS and AP system needs to be setup as FMS tells AP what to do, it even puts in com/nav frequencies as part of picture. Of course, no manual on how to setup FMS although I did write a “cold and dark for 747” and posted it here on forum, it gets you started, but is not complete on FMS, but much better than Checklist in game. They leave out all the switches and FMS stuff, but plane needs that to really perform correctly. I am sure someone is working on Payware Version, PMDG or the like, so hopefully we get a study level version one day.

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Defo not!

But, all good, just keep the weight default for now :slight_smile:

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I just realised!!! In the past when I had the tank FULL 100% for a flight the payload was a at 95% loooooool so why is there such an issue when I increase the payload by 4.9%? haha

When you move the fuel slider the MAX the payload automatically goes up the 95% - ahhhh all confusing lol.

Either way - I am doing what you said and have fuel just enough for my flights now!

When I landed the B747 today - my tank was not too far from empty and plane was nice to handle an the AP was not struggling at all with turns etc

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what does this stand for (the ms)?

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These are “ping” speeds.
They represent the time it takes to get streaming info from the servers.
In this case, less is better.

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what does this stand for the ms on the multiplayer section?

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okok lesss is betterr

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It actually stands for Millie or microseconds, I think. But less is better. Hmmm, last time I checked they were well under 30ms. So, the networks are getting more saturated with the war, I guess.