Questions tagged [boeing-787]

A twin-engine widebody jetliner produced by Boeing since 2007, typically carrying between 242 and 440 passengers. Notable for being the first Boeing jetliner to utilize composites for a large portion of its structure.

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Why does the Boeing 787 engine nacelle exhaust have such an unusual shape?

Why does the Boeing 787 nacelle have this unique shape at the exhaust: I haven't seen it on any other airplanes, does it serve an aerodynamic purpose or help engine efficiency or is it just to look ...
Lnafziger's user avatar
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62 votes
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How can a two-engine B787 create three contrails?

Today I noticed overflying aircraft (over Sydney at FL400) which appeared to have three contrails. When I checked Flightradar24 app, I saw that this overflying aircraft is B787. What would be the ...
kris's user avatar
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46 votes
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Why did my flight leave the gear down for the first 10 minutes of flight? [duplicate]

This morning, I took flight VS156 from LAS to LHR, aboard a 787, tail number G-VSPY according to flightradar24. The pilot made a strange announcement before takeoff - specifically, that due to a ...
catalogue_number's user avatar
41 votes
1 answer
10k views

Why is the 787 tail cone made out of titanium?

In this question there is a drawing of a 787 that shows that the tail cone is made of titanium. Why is such a heavy-duty material like titanium required for the tail cone? I do not see how there ...
h22's user avatar
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35 votes
3 answers
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What are the effects of the Boeing 787's very flexible wings?

I recently came across this picture of the Boeing 787 series aircraft's incredible wingflex: I suppose this is a consequence of using very light CFRP wings, but how does the wingflex itself improve ...
shortstheory's user avatar
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31 votes
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In what circumstances could a 787 stay powered on continuously for 248 days?

The FAA has issued an airworthiness directive for the 787: SUMMARY: We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 787 airplanes. This AD requires a ...
John Wiseman's user avatar
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24 votes
3 answers
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Why does the Boeing 787 have fewer cockpit windows?

Why does the Boeing 787 have fewer cockpit windows? The 787 has only 4 cockpit windows, whereas other airplanes have 6. Here is a comparison between the 787 and 777: ^ 787 V.S. 777 v
TayE's user avatar
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22 votes
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What is a gust alleviation system?

Reading about the 787 it says it has an active gust alleviation system similar to the system used on the B-2 bomber. [1] The gust alleviation patent says: The gust alleviation system picks ...
Jonas G. Drange's user avatar
22 votes
1 answer
7k views

Why do flaperons 'move down then up' on takeoff roll on a 787?

The flaperons on the 787 go through certain motions once the TO/GA is pressed. I've always seen it when the 787 is viewed from behind on takeoff. The motions are completely symmetrical, i.e., not ...
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21 votes
2 answers
14k views

Could the Boeing 787-9 near vertical takeoff demonstration be performed by Airbus A350 aircraft?

I am an aviation enthusiast. A couple of months back I came to know about the difference between piloting Boeing and Airbus planes here. What are the main differences piloting Boeing vs. Airbus ...
Rajdeep Singh's user avatar
21 votes
3 answers
38k views

Does the B787 (Dreamliner) operate with higher cabin pressure?

The Boeing 787 Dreamliner's fuselage is almost completely made of composite carbon fibre material, which is not susceptible to metal fatigue. The main reason why the cabin pressure in a pressurized ...
Philippe Leybaert's user avatar
20 votes
2 answers
11k views

Why do flight attendants on the 787 lock the dimmable windows at different phases of the flight?

I’ve heard of many passengers complaining about the FAs locking the dim setting at different phases of the flight. Seems to be something the passengers definitely don’t like. And the passengers cannot ...
George Clooney In a Mooney's user avatar
19 votes
4 answers
10k views

Did any Boeing 787 operator achieve the 20% fuel efficiency improvement over the 767?

Is there any airline which are able to get the complete 20% fuel efficiency on their 787 with respect to 767 it is going to replace, as told by Boeing. I have read that one of the early customer like ...
NitinG's user avatar
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18 votes
2 answers
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What is the purpose of the fin at the Boeing 787 APU exhaust?

The fin is located under the Boeing 787 APU exhaust as shown in the picture below. Does anybody know the application of this thing or it is used for 'guiding' the APU exhaust? Thanks.
Chaintawit Singkaew's user avatar
16 votes
1 answer
4k views

Why can't Norwegian's Boeing 787 operate from Vegas during hot weather?

In a German news article it was stated that the additional weight (Norwegian puts 291 passengers on their 787-8) leads to operations restrictions in Las Vegas when temperature conditions exceed 40°C. ...
YPA's user avatar
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1 answer
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What is an "all-electric APU"?

Understand that the APS5000 used in the B787 is the first all-electric APU for large commercial aircraft. Source: http://www.pwc.ca/en/engines/auxiliary-power-units Sorry if this sounds too ...
onetime's user avatar
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15 votes
1 answer
5k views

Where are the circuit breakers on the 787?

(787 left, 777 right) Normally found aft of the overhead panel, where are they on the Boeing 787?
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15 votes
1 answer
3k views

What are these paint patches on this 787-8?

What are these paint patches on this British Airways 787-8 (G-ZBJB)?
TayE's user avatar
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14 votes
2 answers
3k views

Why did the Boeing 787 switch back to separate IRS systems?

The Boeing 737 uses two independent IRS systems (see also Why are there two IRS switches on the 737NG?): (source: 737 NG FCOMv2 (11.10.21 - Flight Management, Navigation - Controls and Indicators)) ...
Bianfable's user avatar
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How does the Boeing 787 Dreamliner's glide ratio compare to other airliners?

I just saw a documentary on the design of the Boeing 787 "Dreamliner" and one of the designers said that the wings were inspired by gliders. Looking at the production version of the plane, it is ...
Philippe Leybaert's user avatar
13 votes
4 answers
5k views

Could an airliner with only one functioning engine recover from a stall?

If a modern commercial airplane such as a Boeing 787 would stall with only one functioning engine, is it possible for the pilots to right it or would it require two functioning engines?
Adam Pehrson's user avatar
13 votes
2 answers
11k views

Why does the Boeing 787 use Cabin Air Compressors (CACs)?

What are the advantages of this new air conditioning system compared with the traditional engine bleed systems? More engine output power, or easier adaption to future aircraft design?
No.1 zone's user avatar
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12 votes
1 answer
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Would the wings of a Boeing 787 be snapped off in the same turbulence in which a DC-8 lost an engine and parts of a wing?

From forbes.com: In 1992, a DC 8 cargo aircraft suffered turbulence so severe over the Front Range of Colorado’s Rocky Mountains that its left outboard engine was completely ripped off as well as ...
Willy A's user avatar
12 votes
1 answer
4k views

What is the purpose of the tiny doors used by the 787's laminar control?

The recent Oct 2021 YouTube video (The Insane Engineering of the 787 by Real Engineering) in the related question remarks: [...] tiny doors whose purpose are a mystery to me with little to no ...
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12 votes
2 answers
2k views

What is the correct IATA airplane designator for the Boeing 787-10?

Wikipedia claims 781, most other sources say 78J. I can't find anything authoritative, and IATA has the gall to want US$578 for ...
lambshaanxy's user avatar
11 votes
4 answers
407 views

Do promotional flight routes have a historical precedent?

Right now, a Dreamliner is flying a rather strange path over the USA (see below). The plane took off from Boeing Field airport near Seattle, and is 'drawing' a virtual copy of itself on the map of the ...
Glorfindel's user avatar
11 votes
1 answer
5k views

How much time it will take a B787 to fuel completely when empty?

When a big jet like B787 needs to be fueled with empty tanks, ideally how much time it will take to go full?
NitinG's user avatar
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10 votes
3 answers
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Which commercial aircraft can perform a parallel engine start?

In various Youtube videos, e.g. this one, one can see that the Boeing 787 is capable of a parallel engine start (both engines are started at the same time). Are there any other commercial aircraft ...
Stefan's user avatar
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10 votes
2 answers
3k views

How do virtual circuit breakers work?

In AW189, B787 and few other aircraft/helicopter, the physical breaker has been replaced by virtual breaker, which can be controlled by the MFD (Multi-Function Display). I tried to google the answer, ...
Gianni Alessandro's user avatar
10 votes
1 answer
3k views

What components of the Boeing 787 are made out of titanium?

Inspired by the question, Why is the 787 tail cone made out of titanium?, I want to know what other parts of a Boeing 787 are made out of titanium. We now know, the APU exhaust cone is made out of ...
Noah Krasser's user avatar
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9 votes
2 answers
4k views

How do tyre pressure sensors in aircraft work?

I am specifically interested in the sensors used on the B777 and B787.
Pritam's user avatar
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9 votes
1 answer
3k views

What does "share a type rating" mean?

The Boeing 787 shares its type rating with the 777, but what exactly does that imply? Surely it cannot mean any 777 pilot can just jump into a 787 and fly it. While being similar, the 787 has some ...
Bianfable's user avatar
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9 votes
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Why does the chevron-shaped engine suffer losses in thrust performance?

From here I found out a lot about chevrons on the Boeing 787, but not enough to satisfy why it results in performance loss. My thinking was originally, if they are "cutting triangular holes" in the "...
DrZ214's user avatar
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9 votes
1 answer
354 views

How is structural damage to a composite fuselage detected?

When a service vehicle collides with the aircraft, the plastic nature could hide any subsurface fractures which could propagate as the aircraft goes through cycles. How is potential damage diagnosed ...
Markus Hafener's user avatar
8 votes
3 answers
12k views

How does the nitrogen generation system in a Boeing 777 work?

How does the nitrogen generation system in a B777 work and how does it differ from that used in a B787? Any diagrams will be appreciated.
Pritam's user avatar
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8 votes
1 answer
1k views

Why do the emergency oxygen masks for some 787 premium class seats have an extra 'streamer' to pull them down?

Specifically, on Norwegian 787s, you are briefed: "In economy seats, reach for your mask. In premium seats, pull the streamer for the mask to drop the full distance." (source) Now the ...
Party Ark's user avatar
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7 votes
3 answers
1k views

United’s 787-9 upgrade [duplicate]

I read this article about United increasing their performance of the 787-9. More specifically increasing thrust and range, But it says this will be done over software. How do you make an engine burn ...
Tylerb's user avatar
  • 93
7 votes
3 answers
2k views

Why would a stretch variant need a larger horizontal stabilizer?

With the 787-10 stretch, Vedad Mahmulyin (a Boeing engineer) saved the company millions by implementing a software solution that negated the need to enlarge the horizontal stabilizer. Software again ...
user avatar
7 votes
4 answers
6k views

Who is the owner of the world's only private Boeing 787 Dreamliner?

I have just stumbled across this video and I was wondering, if anyone knows who is the owner of this particular airplane (world's only private Boeing 787 Dreamliner)? I mean a man or a company -- an ...
trejder's user avatar
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7 votes
1 answer
719 views

How much is the Boeing 787 Dreamliner affected by teething troubles now, one year after commencing commercial operations?

Boeing's Dreamliners have been hit several times by small bugs, like fires in the batteries or other engineering issues. Are such incidents frequent when new types are introduced, and how much has the ...
anshabhi's user avatar
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7 votes
1 answer
1k views

How much humidity is being maintained in cabin and cockpit of B787?

I think in general there is less than 10% humidity is being maintained in most of the commercial aircraft but I think they have improved that in the 787. I am not sure how much that is and if the ...
NitinG's user avatar
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6 votes
2 answers
3k views

What is the purpose of the 787 engines extending on landing? [duplicate]

As seen about 53 seconds into this video of the Qantas Dreamliner landing, the engine housings seem to extend upon landing. What specifically is the purpose of this? To balance? To help with air flow?
Mark Mayo's user avatar
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6 votes
2 answers
602 views

How are special flight paths coordinated with ATC?

I assume they have to enter a flightplan for this or do say just say "it's a test, please clear airspace for us around the complete US"? Still flying and completing the right wing. I would ...
Peter's user avatar
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6 votes
1 answer
2k views

Why does the boeing 747-8 have less wing flex than the 787?

If you know the 787 wing flex is much greater than the 747-8's wing why can't the 747-8 have a greater wing flex
Ethan's user avatar
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6 votes
1 answer
2k views

Does the 787 gust alleviation system make a more comfortable ride or for a more stable aircraft?

The 787 active gust alleviation system, similar to the system used on the B-2 bomber, improves ride quality during turbulence. Ride quality in a B2 bomber means a more stable weapons platform. Ride ...
user9993's user avatar
5 votes
1 answer
1k views

What happens if full thrust is applied at cruise altitude for 5-10 minutes on a 787?

What happens when you apply full throttle to the engines of a Boeing 787 at cruise altitude for 5-10 minutes? Other than wasting fuel, what maximum speeds are reached? Does that pose any danger or ...
securitydude5's user avatar
5 votes
1 answer
3k views

Is the A350 more efficent than the B787?

I have wondered this because the Trent 1000 engines are very similar to the Trent XWB engines on the 787. And if the A350 has better efficiency then why do so many airlines purchase the 787?
Ethan's user avatar
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5 votes
1 answer
8k views

What is the maximum pitch for the Boeing 787 Dreamliner?

I recently watched a video of the Boeing 787 training before Farnborough. This aircraft climbed very fast; does someone know the maximum pitch of this aircraft?
Kromen's user avatar
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5 votes
1 answer
438 views

Can the need for an engine overhaul affect the ETOPS rating?

I read this news: http://edition.cnn.com/2016/04/23/us/boeing-dreamliner-engine-fix/index.html So seemingly the reliability of the 787 engines made by General Electric is not as high as expected and ...
sargas's user avatar
  • 175
5 votes
1 answer
490 views

Are Dreamliner windscreens periodically replaced irrespective of damage?

Does Boeing have a statute that commands that the windscreens are changed for new irrespective of no signs of damage or fatigue, and if so, what are the intervals, for safety reasons?
Peter Lynch's user avatar