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787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 7:00 am
by Faro
Comparison of the upward winscreen visibility of a 787 vs an L-1011:





Why the big pinch in the centre of the upward field of view in the 787? I frankly don't see how this is within regulatory minima...


Faro

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 8:28 am
by Starlionblue
If you look at it from more or less the pilot's viewpoint you can see that visibility is fine. You're not sitting right behind the central pillar. I think the L-1011 pilots were also sitting farther from the windshield, which would give them a smaller field of view.

Image

Of course it is within regulation limits. Otherwise it wouldn't have been certified...

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 8:53 am
by aeropix
What regulatory minima have been infringed? Do you have something specific that you think violates regulations on the 787 windscreen?

With all of Boeing's woes, I think it's one thing they got right, and I haven't heard any complaints about visibility on any Boeing airplane. If you're sitting up next to the glass there's plenty of view - you wouldn't fly the plane from the position that the photo was taken.

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 10:04 am
by Max Q
In comparison the visibility from the 727 cockpit was similar to a tank drivers..

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 10:11 am
by zeke
I think the lens used in the 787 photo also distort the comparison

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 10:31 am
by Max Q
I sat in the cockpit jumpseat on several Cathay L1011’s during the ‘70’s and can attest to the incredible visibility

Nothing has come close since

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 4:28 pm
by kalvado
How much of upward visibility you actually need today? I assume less than decades ago, as 737 got eyebrow windows closed. Downward -forward visibility is for ramp - runway - landing ops, apparently. But how often pilots actually look up?

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Fri Nov 08, 2019 6:26 pm
by GalaxyFlyer
Circling to land, 30 degrees of bank.

GF

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Sat Nov 09, 2019 6:50 am
by Faro
aeropix wrote:
What regulatory minima have been infringed? Do you have something specific that you think violates regulations on the 787 windscreen?

With all of Boeing's woes, I think it's one thing they got right, and I haven't heard any complaints about visibility on any Boeing airplane. If you're sitting up next to the glass there's plenty of view - you wouldn't fly the plane from the position that the photo was taken.



I don't actually think this is not within regulatory minima...what I mean is I would like to see that graphic of the 787 visibility from the left seat point-of-view versus the regulatory minima...it would be interesting to see whether the 787 visibility sits just within the upward cockpit visibility margin...

The effect may also be due to the lens used as zeke wrote...and I guess that --as in so many domains-- the Tristar was also in a league of its own when it comes to cockpit visibility too...


Faro

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Sat Nov 09, 2019 7:21 am
by spacecadet
What I think you're seeing there is that the 787 actually has *more* visibility to the sides of those front windows. If you were to actually measure that central pillar, I'll bet it's within an inch of the L1011. That photo is definitely giving you a trick of perspective due to the wider angle lens used in the 787.

If you were to chop the 787 windows from the top of that central pillar straight across horizontally, and shot that photo with the same lens as the L1011, I doubt this topic would even exist.

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Sat Nov 09, 2019 7:35 am
by Max Q
Always thought the 787 nose section looks very similar to the old Comet

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Sat Nov 09, 2019 9:37 am
by Starlionblue
Max Q wrote:
Always thought the 787 nose section looks very similar to the old Comet


Agreed. Very similar. And it is most likely a better shape aerodynamically. I think the miniaturisation of components has a lot to do with it. In the 767/777/A330 era (yes, know a big range of years), radars and electronics were large and you had to have a pointy nose to fit them, even though it was not aerodynamically optimal.

In the A350, which has a nice smoothly tapered nose, you sit way further forward compared to the A330, because (my theory) the stuff in front of you is smaller. We can actually see the tug without leaning way forward.

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Sat Nov 09, 2019 10:05 am
by VSMUT
Starlionblue wrote:
Max Q wrote:
Always thought the 787 nose section looks very similar to the old Comet


Agreed. Very similar. And it is most likely a better shape aerodynamically. I think the miniaturisation of components has a lot to do with it. In the 767/777/A330 era (yes, know a big range of years), radars and electronics were large and you had to have a pointy nose to fit them, even though it was not aerodynamically optimal.

In the A350, which has a nice smoothly tapered nose, you sit way further forward compared to the A330, because (my theory) the stuff in front of you is smaller. We can actually see the tug without leaning way forward.


I'm going to suggest that it has more to do with forward visibility and the technology to build big curved windscreens. Comet and Caravelle had a gazillion small windows and a jungle of framing obstructing the view. 707s through to A320s and A330s reduced the number of windows and frames (and likely cost and weight) by only working with a few flat panes of a limited size. A stepped nose shape is the only way to ensure enough forward view like that.

But lets not forget, Airbus and Boeing took the 777, A320, A330 and A340 nose and window arrangements directly from some 1960s and 70s designs (A300 and 767).

Re: 787 Windscreen Upward Visibility: Why the Big Pinch?

Posted: Sun Nov 10, 2019 4:47 pm
by CeddP
spacecadet wrote:
What I think you're seeing there is that the 787 actually has *more* visibility to the sides of those front windows. If you were to actually measure that central pillar, I'll bet it's within an inch of the L1011. That photo is definitely giving you a trick of perspective due to the wider angle lens used in the 787.

If you were to chop the 787 windows from the top of that central pillar straight across horizontally, and shot that photo with the same lens as the L1011, I doubt this topic would even exist.

Precisely !
Those windows are huge compared to previous generation acfts. You could take the lowest point of this "pinch", extend it horizontally on both sides, and you would still have better visibility than on the 737 for exemple...