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Questions, Boeing 747's Flare and Distance plus Height....

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Hello, Guys!

 

I've few questions:

 

1)- If we see International Flights then we observe that when these flights go over us at 31000 to 38000ft, these flights make smoky lines their behind. A Huge smoky line of white color remains on the sky after their disappearing. Some times, we see lots of white lines, some times small white lines and some times we see nothing but airplane goes in same height. So What effect happens that sometimes these flights don't show smoky white lines?

 

2)- I usually, fly Boeing 747-400 in FSX. I want to ask when should we flare this plane while landing? I flare it 0nm distance away from runway, 600feet height above runway and flare with my own mind (sometimes nose increased too much sometime nose decrease too much and show on). What do you say how much should be the Distance, Height and nose up (Flared) while landing? Which gauge tells us now plane has flared a specific degree?

 

Runway_Upload.jpg

 

 

 

3)- I want to show my landings here at avsim forums. When I take movie of landing from FRAPS, then it becomes of minimum 200MB or >200MB. So what I do? How can I show my landing here. Tell me an easy way. 200MB cannot be uploaded any where.

 

Regards,

 

AP,

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1) If contrails happen or not depends from temperature and humidity too I think.

 

2) I agree with Gear Up

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2) You only want to flare around 30-20 feet above the runway

 

I'm unable to understand. You mean, flare when you're 20-30 feet above the ground. What does this mean? I told you my plane reaches runway threshold when it is 600ft above the ground. What do you mean?

 

And I'm asking about Distance that how much away should I'm when I flare my plane? Even I've given picture and draw arrow lines that you tell me a spot where to flare up?

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told you my plane reaches runway threshold when it is 600ft above the ground. What do you mean?

Then your plane is way too high.

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Then your plane is way too high.

 

So what should be the height at threshold? Please give me suggestion.

 

This is what I do:

 

 

When my plane detects Glide Scope, I reduce the speed from 200knots to 165knots. At 1000ft above the ground my speed is 165knots, so when I reach 1000ft above the ground I turn off Auto Throttle/Speed. When plane goes to 600ft above the ground, I turn-off Autopilot and every thing. Then land the plane manually. What do you say is it good method? If any change is needed then please tell me.

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Autopilot disconnect at 500ft. Aim for a landing speed of around 154 to 156kts...

Above threshold height should not be below 50ft. Flare should be at 10ft. It may appear as the ground is coming up real fast but it's ok

 

Take a look at this video. Note when the 50ft callout is - roughly above threshold. Also note when the PIC begins the flare - when the 10ft callout sounds.

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So what should be the height at threshold? Please give me suggestion.

 

50ft.

 

You should look into basic tutorial on landing the 747. Or even try landing a Cessna first. But anyway, you should be about 50ft at the threshold, ie when crossing the numbers.

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Autopilot disconnect at 500ft.

 

Nop! Man! I'm unable to turn off autopilot at 400ft. At 600ft, my threshold comes, so if I wait for 400ft, then plane will go too too ahead.

 

So what I do so that my threshold should come at 400ft?

 

I remain 4000ft height before detecting Glide Scope. Is it good or not? I've reduce my speed to 146Knots from 200Knots after detecting G/S (as you said). Is it good or not.

 

50ft.

 

You should look into basic tutorial on landing the 747. Or even try landing a Cessna first. But anyway, you should be about 50ft at the threshold, ie when crossing the numbers.

 

How is it possible? Unbelievable. I try again and again

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The big white blocks are just your visual aiming point before you flare. Don't try to touch down before them. If you're on Glide Slope, you would really have to have a very hard landing to touch down in the zone you indicate in your picture, or else have a dangerously lower threshold crossing to begin with. It would be much more reasonable to plan on your main gears contacting the runway even as much as 1000 feet beyond where you are currently trying to touch down.

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Guys! See in the picture (Thumbnail) now Is it correct? In this, I've come at 155Knots and 4000ft Altitude which was reduced after detecting G/S. By this, I've landed successfully on touch down area. Click the Link to enlarge this photo. If problem comes while opening photo then its URL is: http://postimage.org/image/ype1q9z25/

 

Pictures_for_Upload_QQQQQQ.jpg

 

Use the big white blocks as your landing visual aiming point. Don't try to touch down before them. You'll flare and it is normal to land beyond them. If you're on Glide Slope, you would really have to have a very hard landing to touch down in the zone you indicate in your picture, or else have a dangerously lower threshold crossing to begin with. It would be much more reasonable to plan on your main gears contacting the runway about 1000 feet beyond where you are currently trying to touch down.

 

Oops! can we land on these two blocks? See in photo please:

 

Runway_RRRRRR.jpg

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On an ICAO runway those blocks are 1300 feet down the runway. On an American runway, those blocks are 1000 feet down the runway. In a plane like the 747 I think touching down 1500 feet from the threshold is about the minimum you would want to do unless you are really in a hurry to get it down and are willing to accept a harder landing. So yes, you *can* land on those blocks, but it you are on g/s, on speed, and conduct a normal flare, you *won't*.EDIT:My PMDG manual says "It is recommended that the aircraft be flared to touch down on the runway surface between 1000 and 1500 feet from the threshold. As such the pilot should use the 1500 foot markings on the runway as the visual aim point for the approach". So...not quite what I said above...I guess I'm telling you how I do it in the NGX, and that technique must not hold up as well for a big plane like the 747 because of the different geometry between pilot height above the runway and the distance back to the main gear.

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@KingGhidorah:

 

If we land just before these blocks then will runway get any loss or will there any problem? Can we land just before these blocks?

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@KingGhidorah:

 

If we land just before these blocks then will runway get any loss or will there any problem? Can we land just before these blocks?

 

yes, you can land before those blocks, and you can go all the way out to the last set of stripes if you have to. I just find that in a normal landing with a good flare it almost never happens, at least not on the American style runway where those blocks are only 1000 feet from the threshold.

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Take a look at this video. Note when the 50ft callout is - roughly above threshold. Also note when the PIC begins the flare - when the 10ft callout sounds.

You should flare at 50-30' RA in an 747. If you look carefully at your video the Captain starts flaring at 50-40' RA....If you would start flaring at 10' RA with an 747 you would have a VERY hard landing & unhappy passengers!..the 747 & other Heavys has a lot of inertia that has to be stopped...10´ ain't going to do it.

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Nop! Man! I'm unable to turn off autopilot at 400ft. At 600ft, my threshold comes, so if I wait for 400ft, then plane will go too too ahead.

 

So what I do so that my threshold should come at 400ft?

 

I remain 4000ft height before detecting Glide Scope. Is it good or not? I've reduce my speed to 146Knots from 200Knots after detecting G/S (as you said). Is it good or not.

How is it possible? Unbelievable. I try again and again

 

Your problems start with your descent rate (particularly after ATC gives you final instruction to descend to......prior to landing). You should not 'remain at 4000 ft before detecting GS'. That is too high. What this means, is that after capturing the GS, you have to reduce your speed to 146 kts so that you can descend quickly to make it for touchdown. Not good airmanship and not good for the pax.

 

First you need to confirm how far you are from the runway. Eg. if you are 10 nm away, then your altitude should be approx. 3,400 ft. Since you appear to do your landings always with the ILS (ie. capturing both Loc and GS), then of course the ILS will/should bring you in at the right landing profile - you will only need to adjust your speed). And this speed will depend on factors such as aircraft weight, wind and weather conditions and altitude. 146 kts is too low in my estimation; you need to be above 160 kts and reducing this incrementally, until throttles are closed at 50 ft above the runway.

 

Because of the sheer weight of the B747 and the max. allowable speed at full flaps, the aircraft will always do an approach between 0 and 4 degrees AoA (ie. nose up profile: you keep a check on this on your PFD). So just before touchdown, when you start to flare at 20-30 ft, your AoA could go up another 2 or 3 degrees. Of course, you will have armed your spoilers well before this time and after your main undercarriage connects with the deck, you can then engage reverse thrust. The aircraft will on its own begin to lower its nose.

 

And by the way, your last pic of your fresh attempt to land using the other posters' suggestions, look very good. Use your Instant Replay function after each landing to carefully look at and assess your landings. In time, it will become quite natural for you to do a good landing. And, I will try to PM you with a small chart of approx. figures in your Descent profile.

 

Chris

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You should flare at 50-30' RA in an 747. If you look carefully at your video the Captain starts flaring at 50-40' RA....If you would start flaring at 10' RA with an 747 you would have a VERY hard landing & unhappy passengers!..the 747 & other Heavys has a lot of inertia that has to be stopped...10´ ain't going to do it.

 

Yep my bad.. Just took a look at the 744 Manual and the AP starts the flare between 60-40ft, and AT sets idle thrust at 25ft...

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Your problems start with your descent rate (particularly after ATC gives you final instruction to descend to......prior to landing). You should not 'remain at 4000 ft before detecting GS'. That is too high. What this means, is that after capturing the GS, you have to reduce your speed to 146 kts so that you can descend quickly to make it for touchdown. Not good airmanship and not good for the pax.

 

First you need to confirm how far you are from the runway. Eg. if you are 10 nm away, then your altitude should be approx. 3,400 ft. Since you appear to do your landings always with the ILS (ie. capturing both Loc and GS), then of course the ILS will/should bring you in at the right landing profile - you will only need to adjust your speed). And this speed will depend on factors such as aircraft weight, wind and weather conditions and altitude. 146 kts is too low in my estimation; you need to be above 160 kts and reducing this incrementally, until throttles are closed at 50 ft above the runway.

 

Because of the sheer weight of the B747 and the max. allowable speed at full flaps, the aircraft will always do an approach between 0 and 4 degrees AoA (ie. nose up profile: you keep a check on this on your PFD). So just before touchdown, when you start to flare at 20-30 ft, your AoA could go up another 2 or 3 degrees. Of course, you will have armed your spoilers well before this time and after your main undercarriage connects with the deck, you can then engage reverse thrust. The aircraft will on its own begin to lower its nose.

 

And by the way, your last pic of your fresh attempt to land using the other posters' suggestions, look very good. Use your Instant Replay function after each landing to carefully look at and assess your landings. In time, it will become quite natural for you to do a good landing. And, I will try to PM you with a small chart of approx. figures in your Descent profile.

 

Chris

 

Thanks Chris for your detailed explain.

 

 

On an ICAO runway those blocks are 1300 feet down the runway. On an American runway, those blocks are 1000 feet down the runway. In a plane like the 747 I think touching down 1500 feet from the threshold is about the minimum you would want to do unless you are really in a hurry to get it down and are willing to accept a harder landing. So yes, you *can* land on those blocks, but it you are on g/s, on speed, and conduct a normal flare, you *won't*.EDIT:My PMDG manual says "It is recommended that the aircraft be flared to touch down on the runway surface between 1000 and 1500 feet from the threshold. As such the pilot should use the 1500 foot markings on the runway as the visual aim point for the approach". So...not quite what I said above...I guess I'm telling you how I do it in the NGX, and that technique must not hold up as well for a big plane like the 747 because of the different geometry between pilot height above the runway and the distance back to the main gear.

 

Thank you king for also giving me detailed answer,

 

 

 

Now please read my first least post and can anyone answer me of my third question in that post? Which is:

 

 

3)- I want to show my landings here at avsim forums. When I take movie of landing from FRAPS, then it becomes of minimum 200MB or >200MB. So what I do? How can I show my landing here. Tell me an easy way. 200MB cannot be uploaded any where.

 

 

Regards,

 

 

 

Means where can I upload a huge 205MB size video? So that here at AVSIM, expert should see. How it will be done? I request anyone to please tell me an easy way to do this.

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You should make your final descent to minimum altitude. For an approach to LIMF the descent is down to 4,000ft QNH. So in this case you will typically intercept the glide slope at around 15DME. Other airports like EGLL descend to 2500 QNH and again intercept the GS around 12-15DME. In both cases that will give you 10DME to slow the a/c down and configure it for landing.

Always, always (unless the airport plate specifically dictates otherwise) intercept the glide slope from below. Make sure your speeds are within limitations. As for the aiming point the ILS and/or PAPI's will guide you done correctly. In the 747 assuming you have selected the correct flaps and the the correct Vat speed from about 6-7DME from threshold. You will already be in a slight nose up position as you reach screen height. Close the throttles and flare at 30ft. It's not difficult to do. But if your speeds are too high then it becomes a problem. Do not intercept the localiser above 180-190IAS. As you start your descent on the glideslope slow to 160-170. (Bear in mind that no ATC for the sim will give you speed directives as in real life). Make certain that the a/c has slowed to Vat+5 (in ISA conditions) by the inner marker.

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