Questions tagged [boeing-747]
A medium- to long-range four-engine wide-body jetliner (the original "Jumbo Jet") introduced into commercial service in 1970, easily recognizable by its distinctive hump forward of the wings. Different versions typically seat between 266 and 660 passengers.
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Why does the maximum allowable load factor vary with airspeed in some aircraft?
In this ASE answer What is the maximum safe bank angle of a 747?, the author writes:
If we stay with stationary turns (without the "falling out of the sky"
part), the maximum bank angle is ...
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Why some airliners have autostart and others don't?
So some of the more modern FADEC equiped planes (specifically airliners like the 787) have autostart and will self monitor the engines during startup. The one thing that confused me was how a 747 ...
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On the B737 When A and B systems are pretty much each other's back up for most things Why not for flaps? [closed]
Why have a seperate system for flaps? Which is alternate flaps
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What is this instrument for on the 747 flight engineer's panel?
Above the flight engineer's panel in a 747-100 there is an instrument that looks like a curved spirit level.
What was it used for?
source
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What flaps are used for, if the aircraft has already landed? [duplicate]
When watching the below clip in the final approach sequence we can clearly hear setting flabs to 1, 2 and then to maximum.
At 12:05 into the clip, when fully landed ...
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Precautions for LauncherOne off centerline drop
Virgin Orbit's LauncherOne is carried in the spare engine position of its 747 carrier aircraft inboard from the inner engine on the portside wing. At launch, the orbital launch vehicle is dropped from ...
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Can a 747 airfoil be scaled down for smaller jet planes?
At the loss of its acrobatic ability, could an airfoil similar to the 747 be downsized to allow a small jet to climb higher and extend its range?
This plane with its wing profile is highly acrobatic, ...
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What is the thrust specific fuel consumption of a JT9D engine used for the Boeing 747SP?
I searched every inch of the internet still couldn't find the value of JT9D thrust specific fuel consumption (TSFC) , I just found the SFC which is around 0.37.
Can anyone help please?
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What are the procedure for a B747-400 wheel change?
And what are the required tools? I am fascinated by how you do a B747-400 wheel change.
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What is considered a positive rate?
I'm a beginner pilot, and i am trying to perfect my takeoff. What vertical speed is considered a positive rate in a Boeing 747?
Thanks in Advance
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Can a normal jet bridge reach an upper deck?
We have planes with an upper deck since the time the B747 was born. Now we have the A380. I wonder if a normal jet bridge can reach the upper deck of both planes? The scenario in my mind is if an A380 ...
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How tall is the 747-300 without the tail height?
I know that the 747-300 tail height is 63'5", but how tall is the fuselage alone? Also, what is the height of the cargo area and main cabin?
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747 Fuel Drain Ports
I read about the fuel systems on aircraft for a project I'm working on, and I was wondering about the "fuel drain ports" mentioned, which the document stated were used for complete drainage ...
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Why do the 747's wing gear tilt while airborne, but not its body gear?
The 747's sixteen main-landing-gear wheels are distributed over four bogies: two four-wheel wing gear, mounted underneath the inboard wings, and two four-wheel body gear, mounted under the fuselage ...
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What’s the horizontal and vertical tail airfoil and volume of 747-400? [closed]
What’s the horizontal tail volume coefficient of 747-400? What’s the vertical tail volume coefficient of 747-400? What’s the horizontal tail airfoil of 747-400? What’s the vertical tail airfoil of 747-...
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What is the tapered cone on the B747 CF6 engine inlet cowling?
B747 and B767s are supposed to be using exact same GE CF6 engine, and as such their components are interchangeable including inlet cowl as they show to be effective in the IPC.
However some of the 747 ...
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Why does a Boeing 747-8 take more runway length to take off, compared to an Airbus A380?
The Airbus A380 is the largest passenger airliner. That also includes the Boeing 747-8. Meaning, the Boeing 747-8 is smaller than the Airbus A380. As far as I know, smaller planes use less runway ...
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Is this aerodynamic braking procedure normal in a 747?
I found this instagram video via YouTube:
The description in the YouTube video states that:
This aerodynamic baking procedure is applied to reduce wheel brake and engine wear
I have two questions:
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Are the emergency exits on a Boeing 747-400 plug doors?
Rossiya Airlines flight FV5625 to Antalya suffered an incident at the gate when a passenger opened an emergency exit (seems to be the L3 door, from what I can tell) "because they felt too hot&...
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What are these holes at the rear of 747s?
What are these two holes at the rear of most 747s? I've found plenty of answers for the holes on the front of the wing box, but no answers about these back holes.
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Reducing popularity of 4 engine aircraft [duplicate]
We can see that now most latest airplanes by Boeing and Airbus like 737 max or A350 have twin engine configuration instead of 4 engine. And many airlines are discarding iconic 747s and A380s. What is ...
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How can I know the manufacturer of the PFD (Primary Flight Display) of the current mainstream passenger aircraft?
I'm developing a computer vision software based on the photos of these PFD (Primary Flight Display). How can I know the manufacturer of these PFD of the current mainstream passenger aircraft: B737. ...
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Why did TWA800 not stall?
I believe the NTSB account, but based on this graph, http://twa800.com/lahr/zoom-climb.htm, why did the flight not stall after the nose separated?
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Why was the Boeing 747SP unsuccessful?
Why was the 747SP not very successful with sales and longevity in service with the airlines that did purchase it?
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How fast can an airliner (like a Boeing 747) taxi backwards?
Forgive my lack of understanding, I thought I'd just buy a simulator and mess with it. I really don't know much of anything in terms of MSFS2020 or simming really at all.
I realize that airliners can ...
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How much thrust is required for a Boeing 747 to "keep flying" at 4 km altitude?
Not full power, just enough to keep the plane moving at 4km altitude.
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What is the exact wing chord length and thickness for Boeing 747?
I can't find this info anywhere and all they give me is the ratio. However, I need the exact/approximate values
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Does a Boeing 747-830 exist and if it does, is there any difference to a 747-8 (748)
Two years ago I've uploaded a video of the Lufthansas Boeing 747 "D-ABYA" to Youtube. I am currently receiving some angry comments on that video because the title reads "747-830 with ...
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Can aircraft ferry engines for other types of aircraft?
There have been a number of questions that highlighted the fact that the 747 could ferry an engine on an underwing pod.
Was the 747 only capable of ferrying 747 engines? Or was it possible to ferry ...
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Why do you think the 747 extended downwind to 6 miles? [closed]
Why the 747 extended downwind to 6 miles?
Why do you think Horizon turned 90 degrees to join the final?
What is the “rule” regarding Visual Approaches?
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How many LRUs are there in modern aircraft like a Boeing 747 or an Airbus A380?
I work in the Avionics industry. I always wonder, how many Line-Replaceable Units (LRUs) are present in modern aircraft like A380 and Boeing 747.
I understand that number of LRUs varies from customer ...
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What could explain the fact that during 1976-80, I used to hear commercial jets make sonic booms while flying overhead?
I've read on this site & on Wikipedia that there have only been a couple of commercial jet planes in history that have broken the sound barrier--either in testing (without passengers) or during an ...
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How much does each engine on a Boeing 747 weigh? [closed]
The Boeing 747 weighs 404,600 lbs in total, but how much of that does each engine take up?
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Why did early 747s have only two or three windows on the upper deck on each side?
All 747-100s and some 747-200s were built with just three windows on each side of the upper deck.[1] I'm wondering why so few?
Some of the 100s were retro-fitted with ten windows on each side, so ...
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Are there any new orders for the B747 passenger version? [closed]
I was reading an article about the shortcoming and decline in the use of the A380, based on the modification of the model to move people, and there is a comment saying that both the 380 and 747 are ...
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What's the maximum seat configuration for a 747 that is actually used?
I'm curious what model and configuration of the 747 has the most seating capacity actually used somewhere in the world. The Wikipedia page lists "typical" seating, maxing out at 467 (the 747-8). But ...
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Why did the 747-8's freighter version make its first flight before the passenger version?
I have read that the 747-8F entered service in October 2011, almost eight months ahead of the passenger version (747-8I).
Anyone know why this is?
Thanks
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Why does the second floor of the Boeing 747 occupy only part of the plane?
Why does the second floor of the Boeing 747 occupy only part of the plane, while the second floor of the Airbus a380 occupies the entire space of the plane?
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What is the upper deck on converted freighter long-hump 747s used for?
All 747s1 have an upper deck directly behind the elevated cockpit, a legacy of the 747’s genesis as a design for a strategic-airlifter competition (the upper deck and elevated cockpit were partly to ...
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How much torque can a Boeing 747 apply when pitching?
I know this is a weird way of thinking about / quantifying this, but I'm trying to figure out how much torque a 747 can apply to itself when it pitches upwards (turning about an axis from wing to wing,...
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Why does the Pratt & Whitney 747 have an extra engine on the right side but not left side? [duplicate]
What’s the purpose of this design, and why only on one side?
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Best Practices when removing/inspecting/mounting control surfaces?
I am looking for a better way to essentially "mount" the control surfaces from a Boeing 737-747-777-787 and MD-11's. The current process is to just remove them and strap to a table. The issues with ...
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Is it easy for a Boeing 747 pilot to get a second typerating on the 777? [duplicate]
Is this easy and responsible? Since the 747 and 777 have a glass cockpit, you would think this would be easy.
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What would be the minimum number of engines required to climb in a 747?
There was a really good Air Crash Investigation by Nat Geo which showed the British Airways Speedbird 9 issue where volcanic ash swept over all four engines and through the air vents inside the cabin. ...
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What effect does the Space Shuttle have on the Shuttle Carrier 747
I saw a picture of this the other day and it got me thinking... How does having the shuttle on the back of the 747 affect the factors of flight? My guess is that is provides an incredible amount of ...
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Why does taxiing produce large lateral loads on the 747's engine pylons?
While reading through a bunch of old AARs recently, I found (in the context of a 1993 747 in-flight engine separation) this interesting tidbit:
[...] Boeing engineers report that the modifications ...
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How are the 747-400 rudder pedals and tillers connected to the nose wheel?
The Boeing 747-400 Before Taxi Procedure says (emphasis mine):
[...]
Flight controls .............................................. Check C
[...]
Hold the nose wheel tiller during rudder check to ...
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Was a six-engine 747 ever seriously considered by Boeing?
The Boeing 747 can carry a fifth engine on the side. As the airframe looks quite symmetric, I think that it would not be big work to hang a sixth engine on the side as well.
From here, we seem to be ...
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What are these silver stripes on Cosmic Girl for?
Cosmic Girl (a 747-400 used for launching things into space)1 has a network of silver-coloured stripes on its empennage, starting at the (closed-off) last cabin window, and going aftward and upward ...
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What is that letter in the top of the tail of that Jumbo?
Aristotle Socrates Onasis, after marrying Ja. Kennedy, bought, from Boeing, a 742, the Olympic Eagle - now left in Hellikon Airport to rot, after the Olympic Airlines went public ..
At the top of its ...
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