Missing windows discovered on U.S.-bound plane after departing London

[danielvf]

Just to add some color on this from a lighting point of view. The film lights used look like Maxibrutes[1], which are 12,000 watts of old school, non-LED power per fixture. Looks like they used six lights, so 72,000 watts.

Now in a past life, I've stood a similar distance in front of a giant, super diffuse 72,000 watt light, while wearing full body welding protective gear/goggles, and it was cooking hot right through all the leather gear.

However, this looks even worse - it looks like they are using very tight beams on those fixtures. From the photos on the ground with the lights, it looks like only three and half windows are getting lit up. That's an insane amount of power being concentrated into a small space, and yeah, I'd believe it could wreck some damage.

(Hah, just read the AAIB report[2], yes, they are indeed Maxibrutes)

[1] https://www.filmgear.net/index.php?route=product/product&pro...

[2] https://assets.publishing.service.gov.uk/media/6544b3089e05f...

[karaterobot]

Thanks for the context, that's really interesting: big numbers, wow.

Question: why not LED? Is there some quality of incandescent (I assume) bulbs which LEDs can't duplicate more cheaply? I guess so, but what would you say it is?

[exabrial]

Not to diminish your valuable insight, but if they were simulating a sunrise, I doubt they had these at full throttle. My guess is they used old school lightning panels because of the orangey filament glow at lower wattages. WDYT?

[ls612]

I mean insolation at sea level is on the order of several hundred watts/square meter depending on your latitude and the time of day. Sunlight is very bright compared to almost every artificial light source so I'm still surprised that a window designed to bake in direct sunlight for hours was damaged by these film lights.

[OJFord]

The linked AAIB report is pretty interesting, and surprisingly easy reading.

https://assets.publishing.service.gov.uk/media/6544b3089e05f...

Also interesting from the article:

> An engineer and co-pilot went back to take a look at the window

Is that the same person? Or would they ordinarily be flying with 2/3 pilots and also an engineer? Or did they just happen to have an engineer among the nine passengers on board to call upon like they might a doctor?

Although, with 11 crew and 9 passengers, maybe they do just routinely fly with a doctor, engineer, dentist, therapist, ...?! (It's not actually stated, but seems like maybe it is the film studio or whatever's plane, not that it just happened to be loaned out for filming beforehand. So maybe a funny crew list is more likely than otherwise.)

[danielvf]

This was a repositioning flight of a smaller airline, and so everyone on board the airliner was in the industry / worked for the airline. Not a normal flight of passengers.

[Pasorrijer]

In Europe they use Engineer interchangeably with Aviation Mechanic.

If this is a tour company, moving a plane, it's not unreasonable that they'd bring a mechanic along in case they needed an inspection on the way. It's cheaper than contracting out a lot of the time.

[dbcurtis]

I assume they mean “flight engineer” , the 3rd flight deck crew member on planes that require 3 person crew. Although those are rare these days.

[zwieback]

Lights do deliver a lot of energy, even in the day and age of LED.

I worked on machine vision projects back in the pre-LED days and the heat on anything used for high-speed, especially with line scan cameras, where the photon density is higher, can be a real problem. I remember some fish inspection project that failed because the fish was cooked by the time it passed under the lights.

[niccl]

yup. and back in my rock'n'roll days, we used to toast bread for breakfast using two of the 1kW lights that are in the maxibrute

[VohuMana]

I’m really surprised lights used to simulate sunrise placed 20-30ft away could completely melt the foam holding the exterior windows in place.

[dylan604]

I was doing slomo capture of objects being dropped into a small fish tank. I only had a small lighting kit where my largest light was only 750w. To compensate, I placed the lamps mere inches away. By the end of the shoot, the heat melted the top frame of the tank that would normally hold the housing for the tank's light.

Some productions can bring out 10K lamps and larger. They definitely get H O T.

[javawizard]

Oh I don't know. The aircraft appears to be painted with a dark colored paint; that would naturally absorb any heat energy from the lights, and film set lights are really bright.

[defparam]

Is it a common practice for commercial airliners to alternate between being used on a Hollywood set and for regular commercial air travel? Given how important failure analysis is in the airline industry, wouldn't this added complexity in the usage patterns of a commercial jet be a concern?

[throwaheyy]

Shots inside an aircraft usually use a set. If you watch any Netflix series at all, you start to see the same A320-based aircraft cabin set used over and over again in different shows. It looks just like an A320 cabin interior, but split in two lengthways and the aisle widened, with a flat panel added in the ceiling to fill in the gap from the widening. Once you know what to look for you realize it’s the same set every time.

It’s possible they used the actual aircraft in this case because they were filming an ad or some other promotional material for the tour company, perhaps.

[dylan604]

Not in my experience. It's typically an older body sitting on a back lot somewhere that they dress up as needed to make shooting easier. If you think lugging your carry-on luggage through the aisle is rough, just imagine trying to move cinema cameras through. They move the seats out of the way, so all of the support gear can be put in place.

[yread]

The AV Herald article is also enlightening (hah)

https://avherald.com/h?article=50faa50b&opt=0

[this_steve_j]

The studio lamps were placed much closer to the aircraft windows than the minimum safe distance of 10m, and there were a lot of them.

According to the spec sheet for the Maxibrute 12 lamp head [1], it has 12 1000W PAR64 halogen lamps and the surface external can reach 400 C.

The data sheet for an Osram PAR64 1000W lamp [2] has the following safety advice:

“To prevent personal injury or damage to property, halogen lamps may only be operated in suitable luminaires designed with suitable mechanisms (cover panel etc.) to ensure that in the event of a lamp bursting no parts/shards can escape and that during operation no ultraviolet radiation can escape. Because of the heat produced only heat-resistant lamp connections (holders) may be used. Do not operate near people, or any materials that are flammable, sensitive to heat or affected by drying out.

[1] https://www.filmgear.net/image/catalog/Spec/01Maxibrute/info...

[2] https://www.osram.com/appsj/pdc/pdf.do?cid=GPS01_1044353&vid...

[ashleyn]

Second lighting-related incident I've heard about in a week (after the Bored Apes UV incident). Seems proper lighting engineers are unsung heroes?

[smallerfish]

The headline seems like a great unit test for an NLP system (and, it is badly written). We all got the gist, but reading it literally it means the opposite of what it's trying to convey.

[rwmj]

I think I failed the captcha, as I had a picture in my head of literal windows being found inside the cabin and was trying to guess why that would be so important. Stained glass? Stolen from an English country house?

[wg0]

Such word order shuffle German language can afford maybe but English cannot tolerate that much.

I really had to read the headline multiple times and assumed that some windows of historical value were being stolen from London and were probably heading to some museum.

[tlrobinson]

I don’t understand how these two statements are both possible:

> "Several passengers recalled that after takeoff the aircraft cabin seemed noisier and colder than they were used to," investigators wrote

…

> the plane had remained "pressurized normally," investigators wrote.

[abadpoli]

Aircraft windows are double paned. On the inner pane, there is actually a small hole that allows air to pass to the outer pane, and makes it so that the outer pane is holding in the pressure during normal operation.

If the outer pane is cracked (or lost entirely), then the inner pane will take on the pressure. The hole in the inner pane is small enough that the aircraft’s pressurization system can still maintain pressure even if that hole is leaking air.

However that hole likely makes a lot of noise if air is actively rushing through it, and also without the outer pane, there would be less insulation against the cold air and noise outside, and also the missing pane would create an aerodynamic change that I think would cause a lot more noise from the wind.

edit: actually per the AVHerald article, some of the windows were missing both panes (although from the pictures it looks like the inner pane is still intact?), so it must have just been that the pressurization system was just strong enough to keep up with the hole in the fuselage.

[mmcconnell1618]

At up to 10,000 feet I imagine the pressurization system could keep pace with the differential from the missing windows. If they had gone much higher, it might not have been able to keep pace. If the cabin loses pressure at higher altitude, the procedure is to descend to 10,000 feet or less where pressurization is not needed for passenger survival. In this case, the problem was detected around the time they were crossing above 10,000 feet.

[throwawaymaths]

Planes that old are designed to actively pressurize to 6k/8k ft equivalent plus 13k feet is not that high, less high than mt Whitney.

[melevittfl]

Airplanes are not airtight, so the system is designed to continue to pressurise the cabin as the air escapes.

As they didn’t go above 14,000 feet, I’m guessing it could keep up with the pressure loss from the windows.

[yowzadave]

Maybe the windows are double-paned, and the loss of the outer pane resulted in poorer thermal and sound insulation but not a drop in pressure.

[josephcsible]

Isn't that just because the pressurization system had enough capacity that it could keep up with the extra loss of air?

[_a_a_a_]

> and several window panes appeared to have been warped by the thermal heat

that's the worst kind of heat. They were lucky.

[chasil]

Strangely funny, that was the fate of the De Havilland Comet.

https://www.baesystems.com/en/heritage/de-havilland-comet-1-...

[actionfromafar]

Not very similar, the design error of the Comet made the entire cabin fail.

[jakewins]

> window panes appeared to have been warped by the thermal heat

Are there kinds of heat that are not “thermal”?

[TriangleEdge]

"Discovered" is an abuse of language IMO.

[StrangeSmells01]

Sounds like somebody shipped a bug into production.

[Supermancho]

This was a hardware problem or, more specifically, a process problem. The outside inspection should have occurred or the indoor inspection should have caught it. There is no "bug". People are imperfect and failures of all sorts, happen due to that.

[Galacta7]

I'm curious, how does a flight crew not notice a window entirely missing?!? I get that most of the passengers were near the middle of the craft, but wouldn't it still have been fairly noticeable as the flight attendants were walking down the aisle? Or immediately upon takeoff? Why did it take them reaching 13,000 before it was obvious a window was not there? TFA doesn't really say.

My only guess is that the shades pulled down on most of the windows, not making the situation apparent. But even then, it one would imagine a substantial rattle from wind. Even cracking the window of my car at high speed is incredibly noisy, and my car can only go the fraction of the speed of an airplane. This whole thing is confusing.

[ericfrazier]

The windows weren't missing during inspection. They were lost during takeoff and in flight. The article says the plane was used in a theatrical production that involved very hot lights that melted the the window seals. No one noticed the melted seals and when the plane took off the windows came out. They found the windows on the runway.

[jahnu]

Only the outside panes were missing. Hard to notice.