IndianGuy
Posts: 3126
Joined: Fri Jul 07, 2000 3:14 pm

747-400 Flight Profile

Sat Jul 05, 2003 11:26 pm

What is average flight profile of a 747-400 i mean takeoff and descent speeds, angles etc?

I recently had my first flight on a 747-400, a short flight of about 3 hours. The aircraft first levelled off at around 5/6000 feet(just below the clouds) and then climbed to 31000 feet. The climb was pretty shallow (meaning the nose wasnt pointing steeply towards the sky!).

The descent was pretty interesting. The engines noticeable throttled back and the aircraft pretty much nosedived steeply to 15000 feet or so where we kept circling before beginning a more leisurely descent.

Are such "fighter plane" antics quite common on the 744, or was it the pilot having a bad hair day (there was atleast one lady in the cockpit/box-office!)? It was raining lightly at both ends. Could this be a factor?

-Roy
 
XFSUgimpLB41X
Posts: 3961
Joined: Fri Aug 25, 2000 1:18 am

RE: 747-400 Flight Profile

Sun Jul 06, 2003 12:15 am

Sounds more like that was climb and descent restrictions from ATC than the airplane/pilots. The circling that you entered was called a holding pattern- it is flow control into an airport...probably caused by the weather at your destination.
Chicks dig winglets.
 
CX Flyboy
Posts: 6039
Joined: Sun Dec 26, 1999 6:10 pm

RE: 747-400 Flight Profile

Sun Jul 06, 2003 1:25 am

It doesn't really have anything to do with the 744, specifically, but the requirements on that day from ATC, and/or the airport approach procedures.
 
modesto2
Posts: 2671
Joined: Sun Jul 16, 2000 3:44 am

RE: 747-400 Flight Profile

Sun Jul 06, 2003 2:12 am

Flight profiles specific to an aircraft, such as initial cruising altitudes, would not be illustrated in a 3 hour flight. As others have stated, your observations were merely air traffic control restrictions and instructions or standard procedures...nothing more.
 
Guest

RE: 747-400 Flight Profile

Sun Jul 06, 2003 4:17 am

The 747-400 is no (much) different in flying than the "classic" 747s... A few years ago, was invited in Seattle to fly a 400 - did 3 landings in Moses Lake and Boeing Field... Was no much different in "hand flying" and numbers...
xxx
A 747 heavy weights would climb at some 330-335 KIAS, and if light, it climbs at 285-290 KIAS as best rate speeds... rotation on takeoff (initial climb) is some 13 degrees when heavy, and some 18 degrees when light... Rotation itself is done at 10 or 11 degrees, so not to scrape the tail. And I have yet to get a bad landing... very easy and stable to land as well, just stay on the numbers.
xxx
There is no "oh my Gosh that big airplane" flying or handling it. The 747 is a nice stable aircraft to fly... or do you think I am God himself...? - When I train pilots to fly the 747 - I just say "easy to fly, but watch out and learn to taxi it" before you put your main gear in the dirt in the corner of a taxiway...
xxx
In airplanes - all is in proportion - power and weight - and by the way, the 747 is a wonderful glider - 22:1 ratio... I bet your Cessnas only get 15:1...
xxx
Happy contrails  Smile
(s) Skipper

[Edited 2003-07-05 21:36:08]
 
osteogenesis
Posts: 494
Joined: Tue May 27, 2003 9:44 pm

RE: 747-400 Flight Profile

Sun Jul 06, 2003 6:19 am

22:1 Does that mean 1 Km (or whatever you want) down every 22 Km you travel? It would mean about 220 Km if you have to glide from 10000 meters. What would be the ideal speed for gliding a 747? Do you have to extend the flaps?
 
flightsimfreak
Posts: 698
Joined: Sun Oct 29, 2000 9:36 am

RE: 747-400 Flight Profile

Sun Jul 06, 2003 6:25 am

Skipper... I live a mere .8 flying hours by 172 from Moses Lake. It is a favorite cross country destination of mine because I get to see JAL 747s and other heavies including Boeing test aircraft and C-17s in the pattern, along with the occasional F-18 or other fighter. Next time you go there, drop me an e-mail, perhaps I'll fly up there and end up in the pattern with you.
 
Guest

RE: 747-400 Flight Profile

Sun Jul 06, 2003 9:28 am

Dear Osteogenesis -
Correct, from 10,000 meters, you glide 220 km...
The speed would be approximately Vref+70 kts (best L/D) lift over drag...
Typical glide speed, heavy would be 220, and light would be 180 KIAS...
Flaps would be up... flaps down is extra drag...
xxx
(s) Skipper
 
Mr.BA
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RE: 747-400 Flight Profile

Sun Jul 06, 2003 9:56 am

Hi Skipper,

Let's say if you've just reached initial cruising altitude of FL 280 after taking off at MTOW and all four engines failed at the same time. I understand this possibility is so very remote but I wonder what is the procedure? Do you try to keep level at FL 280 while all engines are cut off and wait for the speed to drop to around 220 and then try to glide? Is it possible to glide back to the departing airfield?

And flying the B747, when landing in crosswind and the crab angle's pretty a lot, do yuo recommend de-crabbing the plane or touch down crabbed and centre it after touchdown? Just to hear your opinion.. thanks  Big grin

[Edited 2003-07-06 02:59:11]
Boeing747 万岁!
 
Guest

RE: 747-400 Flight Profile

Sun Jul 06, 2003 11:01 am

Dear Mr. BA... by now, you get to be a 747 expert...!
xxx
There were 747 "gliders" a few times, I recall the British Airways running into ashes of volcano in Indonesia... Boeing has a procedure for that, since the rotation of the engines (windmill) is important to maintain adequate hydraulic pressure for operation of the flight controls - that is a first concern... Remember, all flight controls are hydraulic in the 747, no cables...
xxx
In the scenario you present, you are correct, FL 280 is a typical initial level for a heavy 747, you should remember that a heavy aircraft "glides better" than a light one... kinetic energy - 9,000 meters, yes, likely that if the pilots remember how to glide, they will be able to make it back to departure field.
xxx
I flew in the military, and occasionally "play pilot" with executive jets... an instrument that I miss in the 747 is the angle of attack indicator, as the Learjets have... that wonderful (and simple) instrument would show the pilots the best L over D... the airliners fail to have an AofA indicator, regrettable. When I fly the "Fearjet" I dont care about speeds, I fly with AofA indicator, to tell me what speed to use, i.e. for approach "1/3" in the green is Vref.
xxx
Crosswinds - I looked how "George" (named "Otto" in Germany  Big grin ), the autopilot, flies a coupled approach: crab angle until the flare. I personally keep the crab until 35 feet AGL, then reducing the power to full idle (keeping a little extra power on the upwind side) then at 10 feet AGL, I "kick" the rudders to align the aircraft to the centerline during the flare. That flare is a little firm, compared to my normal landings, since I do not wish the aircraft to drift from centerline, and "float" forever. In any case, the 747 "by PFM - pure f***ing magic" always lands rather smooth.
xxx
The only practical consideration in crosswind is "banking an aircraft" with the nose high (4 engine jets with wing mounted engines) since that attitude brings the outer engines (1 or 4) closer to the ground. I do not indulge in a "wing low" attitude and keep "nose high"... could spell disaster.
xxx
Happy contrails
(s) Skipper

 
POSITIVE RATE
Posts: 2121
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RE: 747-400 Flight Profile

Sun Jul 06, 2003 11:46 am

I think most light aircraft have a glide ratio in the order of 7:1- at least the TB10 did anyway  Smile
 
IndianGuy
Posts: 3126
Joined: Fri Jul 07, 2000 3:14 pm

RE: 747-400 Flight Profile

Sun Jul 06, 2003 12:35 pm


A 747 heavy weights would climb at some 330-335 KIAS, and if light, it climbs at 285-290 KIAS as best rate speeds..

Shouldnt it be the other way around? Lighter aircraft climbing faster? What is the typical VS on ascent and descent?

Also, would step-climbing be really necessary for a short 3 hour flight. Could it not climb str8 to altitude?

-Roy
 
Mr.BA
Posts: 3310
Joined: Sun Sep 24, 2000 12:26 pm

RE: 747-400 Flight Profile

Sun Jul 06, 2003 2:50 pm

Hello Skipper,

"Dear Mr. BA... by now, you get to be a 747 expert...!"............ Big grin Thanks for the nice words.  Smile

Very much thanks for such a detailed explanation! Very nice and interesting to read. One more thing on the "kicking" of rudders to align the nose to the centreline on the runway, do you keep the rudder at that position after touchdown and put the ailerons into the wind or do you release the rudder back to it's centre position? I noticed that the B744 wings are actually more "flexible" than the B747 classics which are a bit more "stiffer" (sorry can't find any other better words to use  Smile). The other day I witnessed a B744 landing in direct crosswind of about 20 knots (sorry we don't get many classics here  Sad) and the pilot did not "de-crab" - He touched down with the crab angle, used the rudder to bring his nose back to the centreline almost simultaneously and put the ailerons into the wind and what a sight... the outboard engine almost struck the tarmac.

Something like this:


View Large View Medium
Click here for bigger photo!

Photo © Frank Schaefer




I've seen B747s putting almost full ailerons into the wind even the spoilerons came up for take-off in crosswinds while the rudder corrects the heading. One question, I understand pilots will gradually put the ailerons back to the neutral position as they gain speed and as they near rotation. But won't it affect the plane? Releasing the ailerons will prevent a flip but won't the aircraft drift on the runway?

Putting ailerons into the wind and having the rudder at the opposite... always thought that was the best way to keep an aircraft straight on the runway in crosswinds... or are there better ways?

Indianguy,

Step climbing are not really necessary for a 3hr flight. I think most airlines (or is it Boeing, I read it somewhere) don't recommend step climbs or rather, climb to a higher altitude when destination is just an hour or so away, wouldn't make much of a difference in fuel savings. And for a 3 hour flight, even if the B744 is at it's Max ZFW with it's 3 hour of fuel can make it to FL 370 or so.

Thanks a lot really appreciate all the help.. ya the B747 master Big grin

Alvin

Edit: You've got to see this:

http://www.planepictures.net/netshow.cgi?74087



[Edited 2003-07-06 08:00:29]
Boeing747 万岁!
 
POSITIVE RATE
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RE: 747-400 Flight Profile

Sun Jul 06, 2003 4:30 pm

What is the max- XWIND limitation for the 747 on a dry runway? Also at what speeds does XWIND first become noticeable in a 747? I'm assuming that say a 5-10 kt XWIND would be barely noiticeable wouldn't it? Given the high speed at landing and the huge mass of the airplane?
 
Guest

RE: 747-400 Flight Profile

Mon Jul 07, 2003 2:27 am

Max crosswind 747 demonstrated 30 knots...
xxx
I say again (and all airplanes do the same) slower climb speed for light weight aircraft, high speed for airplanes at maximum weight...
xxx
Rate of climb intially averages 2,000 fpm... to some 10,000 feet or so, then reduces progressively... the last 2 or 3,000 feet to cruise level might be only at 500 fpm climb... I generally count on a 35 minutes climb to level off at a cruise level of 290 or 310... again, all depends on weight, there are no "standard" numbers applicable -
xxx
After landing in crosswind, correct, we turn the wheel towards the wind, to RH is the wind is from RH... The rudder remains deflected initially, but as the speeds reduce after landing, 60 or less, the deflection does not help any longer. I do not find the 747 any "more" or "less" difficult to handle un crosswinds than any other 4 engine jet I flew, the 707s and the DC8s...
xxx
Friends, I am going for ski vacations 2 weeks in Bariloche (that is a ski resort in the Andes, in Argentina) - it is winter here... I might not be reading much of you during that time period... since I have to listen to my wife and my daughter (my son and I will speak airplanes...)  Big grin
xxx
(s) Skipper

[Edited 2003-07-06 19:30:21]
 
liamksa
Posts: 301
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RE: 747-400 Flight Profile

Mon Jul 07, 2003 10:11 am

One of the interesting things I learnt in aerodynamics was that the gliding distance increases with weight. An interesting concept to get your head around but the maths doesn't lie!  Smile
 
Lu
Posts: 162
Joined: Mon Aug 30, 1999 2:02 pm

RE: 747-400 Flight Profile

Tue Jul 08, 2003 10:57 am

747-400, a big bird, the queen of the planes. But it is not same like the old 747. You can turn the numbers to fly this about 400T bird. It is so easy.

 
Mr.BA
Posts: 3310
Joined: Sun Sep 24, 2000 12:26 pm

RE: 747-400 Flight Profile

Tue Jul 08, 2003 5:06 pm

Thanks Skipper for the information!  Smile
Boeing747 万岁!

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