What Really Caused The Comet Crashes? (BOAC Flight 781 & SAA Flight 201) - DISASTER BREAKDOWN

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Twitter: / chloe_howiecb
This is a de Havilland Comet. In aviation this plane is seen as one of the greatest technological leaps of the 20th century. The Comet was the world’s first Jet passenger plane. Not this particular comet this was a later variant of the plane. But the Comet family first took to the skies in the twilight days of the 1940s. As the world entered a new decade the plane was a symbol of British Engineering, a statement that Britain was cementing itself as a mainstay in the aviation industry, leading the way no less. As the first jet airliner developed behind closed doors, its arrival turned the heads of engineers all over the world. The comet could fly fast, slashing flight times between destinations. The comet could fly higher and provided a greater level of comfort to its passengers.
For half a decade, the comet went unchallenged in the aviation industry. It wasn’t until 1956 when the Soviet Union launched the Tupolev 104 and later with the arrival of the Boeing 707 and DC8 that the plane was met with some kind of competition. For what it all the Comet was worth though, it certainly wasn’t without tragedy. Breaking into new frontiers in the sky, the arrival of the comet seemed to present more technological hurdles than previously thought. The early days of this plane are marred with multiple accidents that claimed dozens of lives. In this video we’ll look a little deeper into the tragic history of the Comet focusing on a particular accident that signalled the beginning of the end of this iconic aircraft.
#aviation
00:00 Intro
01:43 BOAC Flight 781
09:23 Troubled Skies
13:00 South African Airways Flight 201
15:30 It Wasn't The Square Windows
22:03 Meet The Comets
Sources:
www.baaa-acro.com/sites/defau...
aviation-safety.net/database/...
web.archive.org/web/201708272...
www.nms.ac.uk/explore-our-col....
www.baesystems.com/en-uk/heri...
simpleflying.com/last-de-havi...
• YOU have Misunderstood...
www.baaa-acro.com/crash/crash...
www.dh-aircraft.co.uk/aircraft...

[@DisasterBreakdown]

Just a reminder in case anyone has missed it. There will not be a video next Saturday as we move to a new schedule of producing some bigger videos which will se them released as and when they are completed. I am currently working on the next video right now and it should be a pretty big one, I look forward to sharing it with you. Will drop a community post this coming week to keep you updated. This video went out to my Patrons on Patreon 48 hours before going out publicly. Consider joining here from £1 per month: www.patreon.com/DisasterBreakdown Twitter: twitter.com/Chloe_HowieCB

[@robertmcghintheorca49]

The end of an era, but I'm sure that you'll still have some wonderful videos to make for us fans to enjoy. P.S. Since you said at the end of the Korean Air Flight 801 video that you believe that you have covered most major accidents, attacks and incidents involving the Boeing B747, I could comment with a list of other cases that are either low profile or have not been dramatised in the "Mayday" documentary series, or since your videos of Korean Air Flight 7 and Pan American World Airways Flight 103 are outdated, maybe you could remake those. P.P.S. If you want to expand the music you use (I love the music you use for Disaster Breakdown, especially "The Stakeout" by Christoffer Moe Ditlevsen), I highly recommend exploring the music of Kevin Macleod as I love his soundtrack and horror music, and he is the go-to choice for people wanting to use licence free music on KZbin. Well, I'm sure I'll adjust to the new schedule of videos, and I can't wait to see what you bring in the future. Good luck, Chloe. Love from Moray, Scotland!

[@DisasterBreakdown]

@@robertmcghintheorca49 Will say that my next video will involve a Boeing 747, so there are still a few more I could make.

[@giggiddy]

Love your work and the extra care you put into each one. I can only imagine the amount of time it takes to fully produce a complete video. My favorite part of these videos is the mechanical breakdown you include in each. To me the cause is absolutely the most critical point to make in any crash video. And thank you for the longer (over 15 minutes) videos. When I get my finances in a better place, I hope to become a Patreon support er. Cheers

[@grmpEqweer]

​@@DisasterBreakdown Thanks for all you do. My finances will probably be a bit hairy for a little while, I have some adulting to do.

[@scoobydo446]

I’ll run the adds while I make my coffee, so excited for my last Saturday viewing , from Sydney Australia

[@senabecool7232]

The Tu-104 (First Soviet Jet) had its own fair share of issues pertaining to its bomber origin that would be very much an interesting video

[@DisasterBreakdown]

Oh yeah the 104 has its own history. One day I'll get round to it. I really don't know a whole lot about that plane either, there will be tons to learn!

[@serverbf100mr]

Sadly 1 in 5 aircrafts got destoryed

[@longtail7770]

There was also 4 engined Tu 110 but only 5 were built and last wss scrapped in 1995

[@unknownperson3691]

@@serverbf100mrthat’s nearly identical to the 707.

[@HappyBeezerStudios]

A very soviet plane with a very soviet design.

[@nyxqueenofshadows]

i really liked the different structure of this one, following multiple accidents and a single plane type! great video, as always :)

[@DisasterBreakdown]

Thank you!

[@samsngdevice5103]

The design looks like something Ford would come up with

[@beenaplumber8379]

@@samsngdevice5103 Aw, be fair. They were the first. They were breaking new frontiers, and they didn't know all of the variables. Ford has no excuse, only bean counters.

[@LuchinoBruttomesso]

I always wondered who thought it was a good idea to Bring a Jet back into service when a Deadly issue was still being Investigated on,the 2nd accident could have been avoided if they didn’t bring the Comet back into service when BOAC 781 was still being investigated

[@danielnovitadubin8272]

The problem was that nobody knew what brought it down. During the initial investigation, an emergency meeting was held between representatives of BOAC, de Havilland, and the Air Registration Board in order to list possible causes of the crash and find actions which could be taken to stop an another accident from happening. The airplane had crashed into the sea, at a time when underwater recovery was not as sophisticated as today, and there was doubt that the cause would ever be found, and BOAC couldn't keep its Comets on the ground forever because of a single mysterious crash. At the same time, however, it would have been imprudent to release them for service without modifications. Furthermore, de Havilland and BOAC agreed that in their view, the most likely cause was not a structural problem at all, but the explosion of an engine, leading to wing failure.

[@42cerberus]

Boeing obviously thought it was a good idea with the 737 Max series. The major difference being that Boeing KNEW what the problem was. De Havelabd also knew that tge Comet wasn't ready for production. They were aware that the skin around the cockpit was flexing alarmingly on test flights. The problem was that following World War 2, Britain badly needed money. Any delays to the entry to service was deed to be unacceptable as this might lead to losing the lead in jet aircraft. This is covered brilliantly in Empire of the Clouds.

[@marieschappacher5419]

Square Windows ….. not a good idea

[@tobiasherrmann9683]

​@@marieschappacher5419 The windows had nothing to do with the crashes ...

[@bradsanders407]

Donald Trump (amongst many others) said there was no reason to ground the max and it had another deadly accident within months. So we see that no lessons were learned and rarely are.

[@MrBibi86]

*The Comet was a beautiful looking jet. Imagine flying on a turboprop one day and the next on the Comet. what a different flight you would have had*

[@angelsaltamontes7336]

Hopefully not TOO different.

[@HappyBeezerStudios]

​@@angelsaltamontes7336 much quieter and smoother. Also much faster and a much bigger cabin.

[@sandervanderkammen9230]

@@HappyBeezerStudios Also statistically the highest chance you will be killed in a plane crash.. The Comet has the highest loss rate and fatalities per flight, passenger/mile of any jet airliner in history, 1 out of every 3 built crashed or were destroyed in accidents

[@beenaplumber8379]

@@HappyBeezerStudios Quieter? I was thinking all through this video how incredibly loud the Comets must have been, especially toward the rear. Turbojets and early turbofans were insanely loud, and the Comet's 4 engines were built into the structure right up against the cabin instead of being mounted on pylons some distance away. In my own experience, I've never been on a turboprop that was anywhere near as loud as sitting in the back of a 727. I can only imagine how much louder the Comet's configuration might have been.

[@GordonFreeman-sl6pi]

As a frenchman, I take immense proud in the fact that we managed to unite and work together with the country that birthed the Comet, in order to make the Concord. I have a never ending admiration for the genius of our cousins on the other side of the French Channel ;) Breath taking planes made by the genius of British Engineering.

[@titan9259]

7:17 the reason for the skull fractures was because due to the force of the decompression ripped the seats from the floor causing them to hit the ceiling with a lot of force.

[@grmpEqweer]

That's a merciful death, as opposed to drowning in your exploded lungs.🥺

[@flexairz]

Decompression will usually not rip seats from the floor. Explosive decompression will force air out of the aircraft towards the breach. Thereby creating a very strong wind force hitting the passengers bashing them around. These poor souls would not be able to withstand that.

[@YoussefRashedElox]

Yo scientist!

[@jacquesc0usteau]

@@grmpEqweer The damage to their lungs likely killed them first. Head trauma is probably from hitting the water from thousands of feet up and were post-mortem injuries.I wonder if the report is available to read.

[@titan9259]

@@flexairz Remember that in 1954, 16G seats did not exist. Many older aircraft still had weaker 9G seats until as recently as 2009.

[@Sacto1654]

I think people forget that the pressurized DC-6 and Constellation planes cruised at around 24,000 to 26,000 feet altitude, not the 35,000+ feet of the Comet I. As such, the Douglas and Lockheed piston airliners experienced a lot less of the severe pressurization changes that affected the Comet. As such, when the 707 and DC-8 were designed, Boeing and Douglas engineers had to design the structure to withstand the pressurization changes caused by repeated flights to over 31,000 feet altitude.

[@EuropaSman]

The engineers at Boeing and Douglas used the lessons learned from the Comet accidents to make the 707 and DC8 stronger airframes better able to withstand fatigue stressors.

[@thomasbaker6563]

Boing are on record saying that if it hadn't been dehavaland it would have been themselves, metal fatigue in these alloys wasn't a well known subject at the time

[@44hawk28]

Propeller aircraft will fail from pressurization problems have more altitudes not because necessarily of their Metallurgy, but the reciprocating engines also put a lot of frequency stress through the airframe.

[@HappyBeezerStudios]

The entire aircraft industry has shown to learn from mistakes. Flying is so safe nowadays because of all these losses. And that is the right way to do it. Instead of looking for someone to blame, they work to improve things continuously.

[@user-xq2zn8bu9q]

​@@44hawk28Of course, I never thought of that.

[@kevanhubbard9673]

You have helped dispell the myth about the square ⬛ windows as I have always read that that was the problem with the Comet.I have seen a Nimrod flying along the north east English coast between Saltburn and Whitby when I was camping along the cliffs as a child.

[@DisasterBreakdown]

Oh wow I bet that was an amazing sight for a young person. Those engines too!

[@9Tensai9]

Square windows ARE a structural failure point on pressured vessels both in water and in the sky. While it is true that they weren't a particular problem on this specific case the reason why everybody saw the windows and were so quick to point it out was because of precisely that. Tthere's another difference; A completely square window and one with rounded corners aren't the same either. There's a simple way to see it. Pressure is an interesting thing, it's always "pushing" everywhere with the same strenght. It's not like a blunt hit but think it about like this. If you were to hit a square on it's corners it won't bend as easily because it's a strong point but that's just on that particular joint, if you hit it on the sides it will immediatelly bend and break (given the hit is stronger that what the material can take). Now, if you round the corners (making the joint "bigger") that same strenght is distributed more equally so... bigger rounded corners are better right? so... if you "round" the corners enough you just end up with a circle. Circles are better for whistanding pressure cicles. That's why the fuselage is round, that's why everything is rounded, not just the windows. It's also better for aerodynamics. Sure, the concorde had square inntake holes but we should also remember those are made with stronger materials and for different purposes. The spy planes are also "flat" and not rounded, and still work great but then again... different materials for different purposes. So, again. A square window would be bad for a pressured vessel, that's why everyone was so quick to blame it on them. It also requires more maintenance. Changing to rounded windows was a complete improvement. Nowadays we could change back to big rounded square windows, since we have way stronger materials.

[@petemaly8950]

​​@@9Tensai9 The best shape for pressurised cabin aircraft windows is an elliptical shape with the larger dimension being vertical. That's due to the relationship between hoop stress & longitudinal stress in a cylinder shaped pressure vessel. The shape then results in the minimum amount of required strengthening material for a given window area. Other shapes increase the weight of the aircraft for a given window area.

[@jaws666]

And sadly the engines were NEVER the problem to start with

[@stephanieparker1250]

I can’t even imagine how that inspector felt after the second plane he gave a thumbs on, flew into pieces… 💔

[@Paul-Nicer58]

The inspector could not have known & had absolutely no reason to not give the thumbs up at the time.

[@stephanieparker1250]

@@Paul-Nicer58 Logically, that’s correct.. but humans are illogical animals and feel guilt for things we could not have predicted.

[@STARRY_SCARAB]

Even if I don’t stay for the outro, I love hearing you say “Hello, everyone!” at the end of each video. You just sound so cheerful-it’s infectious! Another great video about a frankly fascinating plane. I’ve heard the “square windows” myth so many times and it’s great that we’ve got the whole story here. I’m gonna miss the weekly uploads (they helped get me through my last college semester!) but I can’t wait to see what comes next!

[@HappyBeezerStudios]

While square windows are an obvious issue, it wasn't the big issue. And with circular windows the Comet looks better anyway. it has that kind of space age aesthetics that suggest boundless technological marvels.

[@Dragonchick27]

The Comet was an important step forward in aviation history, though that can never compare to the lives lost. I am excited for whenever you do get to the Tu-104 because that is a masterclass in malarkey

[@user-xq2zn8bu9q]

Tu 104...? I'll look this one up.

[@billballbuster7186]

Metal fatigue caused by cabin pressurisation was a totally unknown phenomenon in the 1940s. The accidents did at least change aircraft building methods and improve safety.

[@hepphepps8356]

It most definitively wasn’t. It is a pressure vessel. Look up submarines, steam locomotives or even tea pots. They had known about this stuff (and their shapes!) for a long time. This was very much incremental, and mostly about bonding techniques for very thin metals.

[@billballbuster7186]

@@hepphepps8356 It was the square cabin windows to blame. Pressurization fatigue caused the airframe to crack at the corners of the windows. The cure was round port holes, used on airliners ever since

[@andrewwarcup684]

The actual failure point was the antenna housing on top of the cabin, not the windows. The other problem was the thin skin that was used.

[@billballbuster7186]

And I believe the type of riveting used.

[@Maddogg-hg5me]

Lessons in aviation are usually paid for in blood, unfortunately, as plane crashes very rarely have outcomes that aren't tragic.

[@analogidc1394]

The first generation Comet, in spite of it's shortcomings was still a wonder to behold.

[@sandervanderkammen9230]

The worst engineering failure in commercial aviation history

[@thesinistersiblings705]

@@sandervanderkammen9230 8 months later, and Boeing is taking this reply as a challenge.

[@sandervanderkammen9230]

@thesinistersiblings705 Boeing makes the safest jet aircraft in history... Boeing is the world's largest aerospace manufacturer while de Havilland? Yeah, after the Comet Disaster they went tits-up.

[@redfalcon6027]

@@thesinistersiblings705ignore the guy, he's always keep on yapping & yapping.

[@thesinistersiblings705]

@@redfalcon6027 I know what the bloke is, they've been commenting the same talking points for the last 10 years.

[@JettTyler17]

Just had a watch of this video, thanks for sharing this Chloe, its without a doubt one of the biggest watershed moments in commercial aviation! I like to think the Comet Disasters paved the way for modern jet powered Boeing & Airbus airliners as we know them today.

[@aimeedean1]

This is perhaps my favourite of the accidents because solving the mystery is so fascinating.

[@EuropaSman]

The only complete surviving Comet 1 is exhibited at the RAF Museum, Cosford, along with the fractured piece of fuselage from G-ALYU from the pressurisation test at RAE Farnborough. I was fortunate enough to watch the last Comet flying when I worked at Boscombe Down in the 1990s. It was a pleasure to see Comet 4c XS235 "Canopus" in the air. That aircraft is now preserved at Bruntingthorpe airfield which is only about 30 miles from where I now live.

[@thejudgmentalcat]

I'd always heard about the "Comet's square windows" - glad to hear what really happened ❤

[@RatPfink66]

no doubt due to some joker's poor reading comprehension and wagging tongue.

[@Machia52612]

Square windows contributed. The squarer the edge the more stress load concentration that contributes to metal fatigue failure. The newer Comets used a wider curved window frame to help dissipate these stress forces as it does today in modern aircraft.

[@lordleonusa]

There are parts of the crashed Comets, including the square windows on display in the Science Museum, London

[@StellaMurano]

Another amazing and riveting video! Thank you for breaking down all of these constructional details of Comet, I actually learnt something. :D It will be tough to say goodbye to your weekly videos, but I'm looking forward to longer ones! Good luck on them! ❤🎉

[@DisasterBreakdown]

Thank you for watching!

[@MacklandsMotors]

Another first class video. Very well researched and put together. The Comet was a trailblazer and the early understanding of high altitude flight just wasn’t there, De Havilland learned from their tragic mistakes but the reputation damage was too far gone. The Boeing 707 was developed in the background and achieved much greater success. I’ll always have a soft spot for the Comet as an early trailblazing innovation. East Fortune is also well worth a visit.

[@DisasterBreakdown]

Thanks so much for watching!

[@moosifer3321]

At least we DID get Comet`s offsring - the Nimrod, ev4entually!

[@commerce-usa]

She was so beautiful in so many ways and blazed the trail for all future commercial jet aircraft.

[@micathedachshund5921]

Your content is amazing, we will wait as long as needed for the next video. RIP victims

[@hamishkay3010]

The comet looks absoulutely beautiful

[@phantomf4747]

My initial guess was metallurgy of the day. The explanation totally makes sense. I have to tip my hat to the investigators for devising the test bed for finally coming up with a cause of the crash. Another great video Chole. Keep 'em coming! -PhanotmF4G

[@skully5531]

this was a very interesting video to watch. my family used to work at De Havilland and my great grandfather worked on comet cockpit control panels so these planes have always had a special place in my heart

[@sandervanderkammen9230]

A truly shameful and humiliating chapter in British aviation history... the real tragedy of the _Comet Disaster_ is that it could have been easily prevented if de Havilland had simply followed well-known and understood industry standards for construction of pressurized cabins made from riveted aluminum alloys. It is vary shameful that those responsible were never punished and that the victims have never been properly honored with an official monument.

[@beenaplumber8379]

I bet your great-grandfather and everyone he worked with were gutted by this. I imagine some of the production workers spent a considerable amount of time replaying their assembly procedures in their minds, wondering if it might have been something they overlooked. (I only hope that's going on now at Boeing.)

[@poop-for-brains]

I work every Saturday, and I've appreciated having one of your videos to reliably watch when I get home. I don't mind the change, whatever works best for you is best for us, but I wanted to say thank you for the post-work 20-minute cool downs you've been providing thus far. I'm excited to see what the expanded time frame does for your creative abilities. This vid is gonna make me look up the Comet 1's manufacturing process, because now I'm wondering if they weren't pre-drilling the rivet holes, for instance, because they figured the skin was so thin, or something.

[@alankeith7866]

Looking forward to your next video. I'm excited for the new longer format!! Thank you for all of your hard work!!!

[@sunnyfon9065]

Thanks for this video, Chloe! Although I have flight in next 2 days, I’m going to watch this whole video, because I’ve been waiting for this to come.

[@ohnowhy700]

been on a binge with this channel lately and it has been an absolute delight! first time ive been this early!

[@DisasterBreakdown]

Wow! Thank you so much for watching my videos!

[@ohnowhy700]

@@DisasterBreakdown thank you too! I'm no pilot or expert in airplanes but your videos are been very informative and interesting hearing about these more unknown airline disasters! Gives me a deeper appreciation of the dedicated work in the aviation industry and safety !!

[@planeoldsimp272]

Thank u so much Chloe for this channel is one of my favorites!

[@DisasterBreakdown]

Thank you so much for watching!

[@hooverkinz]

I love videos like this as well as your regular episodes. I love the idea of breaking down the incidents tied to one type of aircraft. I often get the types confused when they’re all separate videos so these are so interesting. I’d love to see more and perhaps the same format but discussing a specific airport? Keep up the great work Chloe you’re my fav channel❤️ edit: I would also love your take on the story oh MH370. I’ve heard many differing facts and I know your research and presentation is always top notch. It also hasn’t been really talked about in years but new evidence has been found recently showing the landing gear was likely down when it hit the water which raises more interesting questions.

[@grmpEqweer]

I'm loving the video footage you got of the museum piece. Lovely. Thank you.❤

[@kesfitzgerald1084]

This is probably the best video on this subject. Great effort.

[@MarvinHartmann452]

No matter the flaws it may have, that plane was magnificent. It emanate from the pictures you took a sense of nostalgia for a long lost exiting era.

[@chdreturns]

Agreed, up with the Concorde as one of the prettiest passenger planes ever made.

[@MarvinHartmann452]

​@@chdreturns Yeah it was one of my lifetime dreams to be able to fly in it. But I didn't get the chance to do so. It was a technical marvel. Also from a time of exiting achievements.

[@beenaplumber8379]

Some say it evokes nostalgia, others say it looks futuristic. I think it looks like what people long ago thought the future would look like, almost like a Jetsons cartoon. We were supposed to be driving flying cars, taking pills instead of meals, living on Mars, and communicating by video telephone by now. Ok, we do the video phone thing - when we want to - but the 1950s ideas of what the future would look like was off by a wide margin, thought it was incredibly exciting and fun to speculate.

[@brianmuhlingBUM]

A great explanation of the tragic Comet! Well done. Awaiting the new format in 2 weeks. 😊

[@00muinamir]

I'll miss the routine of having my Saturday morning cup of tea while watching a new episode, but I'm stoked for your more in-depth videos!

[@DannoAviation]

A very well-structured and thorough video into the history of the Comet… brilliant work!

[@jswatts1967]

Thank you for making such an exhaustive and well-researched video on the Comet. I've watched many on this aircraft, but yours is by far the best I have see. Bravo!

[@pipedreams766]

i like this longer format! i look forward to your next release

[@Aisuzuni]

I really enjoyed this longer format ! I cannot wait for the next one

[@ValerieGriner]

I'm a new subscriber and I LOVE, LOVE, LOVE your videos! You do a beautiful job on these and have the BEST voice I've ever heard on a KZbin channel. Also, I learn sooo much from the great comments posted by your viewers. Thank-you so much for these videos. (From Georgia/USA)

[@dmav522]

Great video as always Chloe!

[@ronnie8274]

Great video Chloe. I have really enjoyed all of your videos. That being said, I don't like disaster's, it's the detail you go into that I appreciate. Thanks for all that you do, Ronnie

[@judywein3282]

Just found ur channel. Just brilliant. I watch air crash videos alot, but yours are hands down the best I've seen. And more detailed info than all the others. Thank you for your hard work and research. Subscribed....

[@MrStillions]

Great, as always. Thank you for these. :)

[@twistedyogert]

This thing looks modern on the outside. I can only imagine what people thought when this thing was introduced. Couple that with post WWII optimism about the future and you've got a recipe for awesome. It's really sad that such a pioneering technology was cut short by disaster. However it did make future aircraft much safer so perhaps something good came out of these accidents.

[@itsyourmumsgf]

im getting ready for a party rn and this is exactly the background video i needed! have a good weekend chloe 🫶

[@DisasterBreakdown]

Have fun!

[@michaelmitchell9612]

Thanks for another great interesting video!

[@arutabaga8264]

Great chronicling of the Comet’s evolution and history. Very informative and interesting. It was a beautiful plane. I did not know about the Nimrod or the 4 versions. Thank you.

[@godarkertilldeath]

Havent had one of your videos come in my feed for quite a while. Actually went to like and subscribe and seen i was already sub'd. Keep up the great content. Loved this one. 👍

[@dogmemes69]

great video keep up the efforts 😊

[@gusm5128]

You do a fantastic job with these videos 🛩️

[@DisasterBreakdown]

Thank you!

[@evieliney1002]

Keep up your great work

[@SP3NTT]

Great content as always

[@wtorules4743]

Thanks for a great video. East Fortune is a must for any plane enthusiasts. Definitely worth a visit, so much to see including the jewel in the crown Concorde.

[@johnny5805]

Before it goes to bed at night, the DC-10 checks under it's bed for The Comet.

[@RACECAR]

There's some morbid, slightly haunted irony about these incidents wherean aircraft called the "Comet" basically broke apart as they came down from high in the sky.

[@TomekSw]

I was in this comet in February. Great experience. Thanks for the video! ❤

[@thomaspiedmont]

I'm kinda gonna miss the weekly Saturday alert for your videos, but if it's gonna be for a even better content (better than the one you're already producing), so be welcome then 😬 Great work as always Chlöe 👍🏼

[@UBrickIFix]

Great B-Roll footage. Enjoy seeing video of the insides of the planes rather than graphics. Great work as always! ❤

[@bluealice1386]

Awesome as usual Chloe 💙

[@tanmay0108]

Good video mate

[@DisasterBreakdown]

Thank you!

[@bazza945]

The postmortems for the Elba Comet disaster was the responsibility of the Italian authorities. An Italian pathologist found the similarities of injuries amongst the victims.

[@charlotteinnocent8752]

Thank you for the in depth. Some people dumb it down to "it was just the windows" like we can't comprehend rivets and materials... Good to get the story straight.

[@michduncg]

Indeed. I remember seeing a documentary a while ago that revealed it was the original intention to Redux the windows to the fuselage like a lot of the Comets structure but that the window assemblies were too heavy so they had to resort to riveting them in and it was the rivet holes that reduced the strength and where fatigue started.

[@jocelynstclair3901]

Thank you Chloe. This video took me back to February 1980 when I was 16 and flew from Gatwick to Milan on a Dan Air Comet 4 when the 6th form college I went to bravely took a bunch of us teenagers on a skiing trip to Bardonecchia in the Italian Alps. The flight was fine but the transfer from Milan to the ski resort was hairy....................shall I just say Italian coach drivers?!

[@thhseeking]

Interestingly, you mentioned the Caravelle at the end. Sud-Aviation licenced the design of the Comet's nose for the Caravelle.

[@sandervanderkammen9230]

The Comets nose was stolen from the Boeing 307, the world's first pressurized airliner.

[@Paul-Nicer58]

​@@sandervanderkammen9230 *UPDATE* In fact the Comets nose was no more copied from the 307 than putting a curved & pointed end cap on a tube would be copying. The Comet nose had some significant & unique features which Sud Aviation licensed for use on their Caravelle. They also purchased plan drawings & a section of fuselage nose. *_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture however they were clearly not safer._* How things were back then - *_Accident losses - % of aircraft built._* DeHavilland Comet 4 UK 14% DeHavilland Comet all mks 17% Vickers VC10 UK 5% *_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_* Douglas DC-1 99% Douglas DC-2 47% Douglas DC-3 30% Douglas DC-4 26% Boeing s300 72% Boeing 307 70% Boeing 247 48% Boeing 707 20% Lockheed Electra Turboprop 29% Fairchild FH-227 30% McDonnell Douglas DC-8 14% Sud Aviation Caravelle 15% All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights. *The DH Comet - World Firsts.* 1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet. The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked). The 1937 Boeing 307 piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing. Same for the B377 piston engine airliner, only 4 psi pressurisation & not a jet. Boeing did not put high altitude commercial jet airliners into service until 10 years after the Comet first flew. 1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS. 1st jet airliner to cross the Atlantic. 1st jet aircraft to do a world circumnavigation flights series. *Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.* *_De Havilland did indeed always work to better than industry standards at the time, no evidence of negligence ever being produced in relation to the DH Comet._*

[@jimsteinway695]

Your videos are very nice to watch

[@antoniobranch]

Thanks!...keep them coming.

[@DisasterBreakdown]

Thanks for the super thanks!

[@stuartmiller7419]

25:10 Nice homage to review brah, Chloe. Your videos are full of surprises.

[@barryvincentredmond3973]

The comet 4 was the first commercial passenger jet to fly from London to New York in October1958.Before the Boeing 707.Must have been a wonderful flight for the passengers with champagne flowing.!.Much booing in New York on arrival as the Americans didnt do a transatlantic passenger flight first.

[@beenaplumber8379]

Much booing? This wasn't the space race. It was a sales race, sure, but Americans can certainly congratulate our friends when they win an honest victory. We're not that petty. The Comet was never going to recover in the market by 1958, and Boeing knew they had a great plane that would dominate.

[@spellmon1]

Nice work Chloe

[@keithposter5543]

Fascinating - thank you

[@mayav927]

Random but thank you for putting the name of the music on the video. I love the music and often go to listen to it later

[@russbrown6453]

I must admit the engine arodynamically location is well designed. Current engine location seems akword, heavy, scarey... I can remember (recently) watching the current engines shake, wabble, etc...when in flight...

[@TwoWholeWorms]

Absolutely devastating if there's an engine failure, though. Could literally tear the wing off. :/

[@Rick-ve5lx]

It’s much easier to replace an engine on a pylon. The man-hours saved would probably outweigh the savings in fuel due to drag, I’m guessing.

[@shrimpflea]

@@Rick-ve5lx Yes both of those plus the fact that you simply can't fit a huge modern high-bypass engine in the wing.

[@mazdaman0075]

Hi Chloe, loved this episode and thank you for explaining that the fault was actually not in the square windows. I consider myself an av geek and have read a fair bit on the Comet accidents, but I was also under the mistaken impression that the accidents were purely due to the window design. Your videos are very well presented, especially your very in-depth video on the 737 rudder issues, which must have taken a lot of time and research. Subscribed to your channel.

[@jackalcrackle]

I'm curious as to why the exploded lungs from comet depressurization didn't seem to really occur on rapid depressurization on modern planes, such as that of the united 747 or aloha 737 incidents

[@00muinamir]

IIRC, those two flights were at much lower altitudes when they depressurized.

[@ClefairyRox]

My guess is altitude. The explosive decompression on both of those flights happened not long after takeoff; somewhere around 20,000-24,000 feet for both from what I found According to the video the Comet flew at altitudes up to 42,000 feet. That's almost twice as high up, with the air being a lot thinner to match. If the Comets broke apart at that altitude, that would explain the dramatic lung injuries.

[@flexairz]

Because this was a not a rapid but an explosive decompression.

[@steve3291]

TWA 800 was at just 16000 ft when it exploded and Aloha air was at 26000 ft so both significantly lower than the 36000 ft when the Comet decompressed. Air India 182 exploded (due to a bomb) over the Atlantic in cruise at 31000 ft and passengers near the bomb site suffered similar injuries to those on the Comet.

[@R8andGT3Fan]

Obviously sad, but fascinating story and video! Can't wait for the new, bigger videos... 😃

[@thomashopkins2609]

If I remember correctly there was a Comet located at O'Hare airport for years. I think someone tried to fly it without proper clearance and the tires were flattened to prevent any future attempts. I think it was painted with reference to nudist flights or something like that.

[@evieliney1002]

Hi I love watching you love your work bye😀

[@syd7429]

She doesn’t I’m her friend she’s a little lying

[@MissWitchiepoo]

There are some good disaster videos on KZbin but I especially love yours they are my favorites. How a person speaks and their voice means a lot to me and you make me see it all in my mind and your voice is so nice to listen to. I was on a SAS plane for the first time in 1968 and I was only 8 years old. I saw the sun rise which was so beautiful. This was at a time when people were served food in planes. We got a menu with drawings of Scandinavians in National clothing, so we could see what we were having. I still have all my menus meaning my mom took us back and then decided to give my dad another chance then it was back again to New York, so 4 menus each. There was also a gift given to my sis and I to do on the long flight which was for me flags from all over the world and coins that were stickers so I had to match them. I still have that too and even our tickets. We also got a bag of peanuts. There was a large screen this was of course before the big tv's and we had to pay a dollar each for earphones but my mom couldn't afford it and since we didn't speak English it didn't much matter. I'm just happy they didn't show Airport which I think came out in 1970. The first flight, there was a snow storm in New York but being a kid I didn't notice. I just wanted to share what it was like in the old days because now it's so different. My mom had all the letters she had sent her sister and written them in a book from first to last and what is wonderful about it is she tells about things Americans wouldn't think of telling and even wrote the prices she paid for things like she bought us dresses for 1 dollar each and they were so nice. I would like to give it all to our immigrant museum one day. I wasn't afraid to fly as a kid but that changed and I was terrified;)

[@canadasleftcoast.5744]

The very first crash of a commercial jet was a Canadian Pacific Comet in Karachi on March 3rd 1953. Pilot error is suspected in that crash.

[@palemale2501]

The East Fortune Aircraft museum (j25 miles east of Edinburgh, Scotland), has this Comet and along with many other aircraft, also houses a Concorde indoors - you can step inside and be surprised at how narrow and cramped seems, yet all the seats are First Class.

[@SinaLaJuanaLewis]

They get better and better❤

[@chriswatson6231]

I was born in 1971 and at the age of about 5 i had a childrens engineering book that I read to get to sleep. It had a chapter on the Comet and explained the destructive water box test. This meant that I was reading about the ceiling/roof failure point in about 1976 (also the book was published well before that year). There was no mention at all about square windows. As an adult I assumed the window shape theory was a 'new revelation'. Now it seems my children's book got it right from the get go

[@djpalindrome]

The ‘square’ windows did unquestionably act as stress concentrators, contributing to the propagation of fatigue cracks around the circumference of the airframe

[@sandervanderkammen9230]

Wreckage recovered completely debunked de Havilland red herring theories, the passenger windows were not in any way responsible for the catastrophic in-flight structural failures

[@sandervanderkammen9230]

@@bfa-xi1py Yes, that is correct... and it's not the origins of the stress cracks that caused the catastrophic in-flight structural failures... it was the design of the fuselage itself that allowed the cracks to join up and cause the instantaneous structural failures.

[@MontoyaGamer1_Entertainment]

The World's 1st Jet Airliner

[@johnjephcote7636]

De Havilland had exhaustively tested every component beyond the specs of the time but not as an entire aircraft. Only afterwards was the entire fuselage tested for stressing over multiple cycles in a water tank. Redux bonding (developed for the Hornet fighter) was extensively employed but it appeared too complicated for the window insertion and these had to be punched into the thin skin which weakened the structure and set the scene for future stress cracking.

[@thomasgreen8894]

As soon as I saw (comet) I already knew how they found the default. I saw this a long time ago on air disasters or one of them shows.

[@syd7429]

Boac 781 was one I watched on air crash investigation and so it’s good to see it

[@titan9259]

seconds from disaster*

[@syd7429]

Oh yes my mistake e

[@syd7429]

So sad to see the Saturday vids go but I’ve always wanted to see the comet

[@DisasterBreakdown]

Me too but bigger and better videos are already in the works!

[@syd7429]

Oo exciting

[@gcrav]

Bottom line, all of the factors contributing to the Comet failures followed from DeHavilland's insistence on using their Ghost engine, underpowered for installation on transport aircraft and already technologically surpassed by Pratt & Whitney and Rolls-Royce. The centrifugal compressor was at the end its potential, while axial compressor engines were the way of the future. Rolls-Royce had recently seen the light and abandoned their dead-end efforts with the centrifugal compressor, following Pratt & Whitney (in turn following Jumo) with development of axial compressor engines. The consequences of the underpowered Ghost engine were 1) inadequate takeoff performance (resulting in the first Comet crash), 2) weight restrictions compromising the robustness of the airframe, required to attain takeoff performance with the underpowered engines while carrying commercially viable loads, 3) an unprecedented flight profile required to gain a speed advantage over piston-driven aircraft, again following from the inadequate power of the engines at lower altitudes, and 4) a dangerously thin margin of safety with the light airframe at the altitudes required for optimal performance. This video does a service in pointing out that constructing an airframe sufficient to withstand high altitude pressurization loads was not some unprecedented problem encountered only by DeHavilland; it was only a problem arising from the restrictions imposed by the imperative of attaining the desired aircraft performance with inadequate engine power. The most ambitious pressure hull design was attempted not by the manufacturers with a body of experience in pressurized metal hulls, but by a manufacturer that was going in a virtual quantum leap from unpressurized wood-and-fabric and plywood craft to an extremely tightly constrained pressurized metal design. They were in over their heads with the imperative of being "FIRST!" It's also a little mystifying to me why DeHavilland used the wing root engine configuration on later versions of the Comet after pylon mounts had been clearly shown to be the better configuration, not only for maintenance but also for aerodynamic efficiency. As it turned out, whatever drag advantage was attained with the wing root configuration was more than offset by the less efficient flight trim required to overcome the adverse rotation inherent in the thrust direction with the engines within the wings. And that's not even considering the advantages of having air intakes in clean air without the engine-starving pressure anomalies that can occur at the leading edges of the wings. The continued use of a discredited engine mount configuration reflected some engineering priorities that DeHavilland certainly deserved to go out of business over.

[@sandervanderkammen9230]

Excellent comments, very knowledgeable and concise.

[@peterosborne6823]

Not to nit pick too much but considering that the RR Avon was not available until a year after the comet's first flight, the Jumo 004 with less than half the thrust of the Ghost was German and WW2 had just ended AND Pratt and Whitney had their first run of an Axial Compressor Engine in 1950 one year after the first flight of the Comet... How could they not have insisted on the RR Ghost ?? It also doesn't mystify me that they didn't want to do a complete redesign, certification and name change just to pylon mount their engines, aircraft manufactures still do everything that they can to only do partial re-certifications on their aircraft instead of full re-certifications.

[@gcrav]

@@peterosborne6823 That's certainly an interesting point about avoiding full recertifications. That was the underlying issue with development of the 737 Max - Boeing was doing everything they could to avoid full recertification for a new airframe, even though the 737 design had become a dog in the era of the latest turbofan engines. Avoiding full recertification in the situations encountered by Boeing and DeHavilland is perhaps understandable, but that doesn't make it the right path. Knowingly carrying forward design flaws is not a way for an aircraft manufacturer to remain competitive, and that applies as much to Boeing as DeHavilland. There was one more player in the jet engine market, General Electric, who had been producing axial compressor engines since the mid 1940s and had their 7,400 lbf model installed in the B-47. Even those outpowered the puny Ghost engines and showed them to be obsolete. DeHavilland would have been better off assessing the development of jet engines and designing their aircraft around engines with adequate takeoff performance for commercial loads, which would not have delayed the introduction of the Comet by that much and certainly not enough to lose an advantage over Lockheed, Douglas, or especially Boeing (the weak sister in the American commercial aircraft market at the time). As it turned out, DeHavilland needn't have worried about getting scooped in the jet transport space by the Americans, as they were focused on military applications before commercial applications of jet power. The 707 was a spinoff of the KC-135 aerial tanker project of the mid-1950s. Jet transport wasn't a huge priority for Douglas and Lockheed either, until it became evident that something big was coming from Boeing in that space. Lockheed was more focused on developing turboprop aircraft for their next generation and Douglas was waiting until they could build something more powerful, bigger, and faster than the 707, which would be the DC-8. As it turned out, the Comet 1 was merely a commercially and technically dubious stunt by DeHavilland that ended up a huge embarrassment and lesson in too-clever-by-half engineering.

[@peterosborne6823]

You are totally correct about General Electric @@gcrav but we look at things through a different lens these days, back then the UK was the leader in Aviation and selling aircraft was paying off their war debts so the pressure was on all UK aircraft manufactures to stay ahead of the game. Even though the US and UK were and still are allies they were also competitors in one of the most lucrative markets in the world so De Havilland would have had to ask the UK parliament before they could have even tried to approach GE to develop a civilian engine for them and then GE most likely would have refused as the UK parliament had the ability to cancel any permission that they may have granted at any time the parliament chose to and if GE didn't refuse to develop an engine then the UK would get suspicious that GE would be handing over any information they got about the Comet to the aircraft manufacturers in the US. I personally feel that the Comet is a very misunderstood aircraft as it was designed in a time where everything was about top speed and national pride. The design philosophy of the Comet was similar to design philosophy of the Concord where both were to be the fastest, highest flying novelty passenger aircraft of the day with a relatively short lifespan expectancy, except that technology, manufacturing techniques and knowledge of metal fatigue had advanced by leaps and bounds by the time of the Concord. I do beg to differ a little bit about the 737, it was always a dog as it was a thrown together design to compete with the DC9 much like the DC10 was a thrown together design to compete with the 747. The stretching of both the 737 and DC10/MD11 amplified the shortcomings of their designs and has shown that aircraft manufactures should listen more to their engineers than to their customers as it would have been cheaper for Boeing to pay for pilot retraining on a clean sheet aircraft than what the Max has cost them. But yeah you do get my point about full recertifaction and yeah it should only be used for fixing safety issues (ie. b707 stainless steel tail sections and DC10 rear floors/cargo doors) not for major modifications to an airframe. The Boeing, Lockheed, Douglas thing was more of a marketing thing... Douglas wasn't interested in jets as he commented something along the lines of "De Havilland had already done it" (creating a super fast novelty passenger aircraft) so his focus was on more efficient long-range piston engine aircraft. Lockheed went with turboprops as a transition to jets as most passengers were already familiar with flying in aircraft with propellers so they felt that passengers would be more at ease with a propeller aircraft and Boeing were going for military applications where keeping up with their fighters and shifting bulk items at faster would give their military an advantage over other militaries. It was only when Douglas was pushed from within his own company to create a jet aircraft that Boeing upped their game to compete with Douglas as well, unfortunately both Boeing and Douglas made many mistakes with Douglas not caring about the jet development program and Boeing scrambling to change from a 5 abreast design to a 6 abreast design... the strangest part is that in Douglas not caring and the Douglas design team not testing their new wing design they accidentally stumbled onto the recipe for making long-range jet aircraft when they were focusing on make long-range piston engine aircraft.

[@peterosborne6823]

Sorry my last comment should read "and yeah partial recertifications should only be used for fixing safety issues (ie. b707 stainless... " in the third paragraph.

[@KatDoodlesDogs]

Excellent video as always, the repeated references to “aluminum” must have been painful😂

[@royfearn4345]

It's very misleading to show thumbnails of the earlier and late model Comets. The Comet 4 in its many sub-marques was totally reliable and must not be confused with the square-windowed early models.

[@sandervanderkammen9230]

The Comet 4 has the highest loss rate and fatalities statistics of any jet airliner in history except for its predecessor the Comet 1 which had its airworthiness certification permanently revoked in 1958 and never returned to revenue service.

[@salvagedb2470]

We went to Majorca in the late 70's on the lengthened Comet , for what I remember the interior and seating was starting to show its age ..

[@petermills34]

I flew on the comet 4 from London to Doha in 1962 , I was in boarding school in Yeovil with my sister

[@sandervanderkammen9230]

*de Havilland Aircraft Company* *Our Motto:* *_"50% isnt really that bad is it?"_*

[@Paul-Nicer58]

​@WilhelmKarsten Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should note good with much awestruckness & extreme wonderment. *UPDATE MORE BREAKING NEWS ETC* *_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._* How things were back then - *_Accident losses - % of aircraft built._* DeHavilland Comet 4 UK 14% DeHavilland Comet all mks 17% Vickers VC10 UK 5% *_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_* Douglas DC-1 99% Douglas DC-2 47% Douglas DC-3 30% Douglas DC-4 26% Boeing s300 72% Boeing 307 70% Boeing 247 48% Boeing 707 20% Lockheed Electra Turboprop 29% Fairchild FH-227 30% McDonnell Douglas DC-8 14% Sud Aviation Caravelle 15% Canadair CL-44 Turboprop 46% Convair CV-580 Turboprop 22% A comparison of more recent aircraft. Accident losses comparison examples. 1970s - 1980s % of total Aircraft built Similar aircraft type, date / decade, useage, size. Biz Jets BAe-125-800 1.7 % Beechcraft Beechjet 400 2.2 % Cessna 550 Citation II 7.1 % Learjet 35 / 36 12 % Beechcraft 1900 6% Dassault Falcon 10 11.5% Aérospatiale SN.601 22.5% Medium size jets / Turboprops. BAe-146 5.1% Fokker 100 6% McDonnell Douglas DC-9-30 9.5% Fairchild FH-227 30% McDonnell Douglas DC-8 14% Canadair CL-44 Turboprop 46% Convair CV-580 Turboprop 22% Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct. All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights. *The DH Comet - World Firsts.* 1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet. The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked). The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing. 1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS. 1st jet airliner to cross the Atlantic. 1st jet aircraft to do a world circumnavigation flights series. *Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.* *_De Havilland did indeed always work to better than industry standards at the time, no evidence of negligence ever being produced in relation to the DH Comet._* The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet. *_Other interesting World firsts_* *Vickers Viscount Turboprop Airliner 1947* *Gloster Meteor Turboprop Aircraft 1945* They might like to answer these questions. *Which airline has just ordered* *60 RR England Trent XWB Engines* *& What aircraft are the engines for?* _Bonus question for 10 points._ Which country has the *World's Highest Combined Per Capita* *Nuclear + Defence + Aerospace Sector Activity?* 👍 Cheers 🙂 . ... ... . . ... . . xcvcvcvcvcvcvxiiivcxvv

[@lordleonusa]

Don't forget the Comet on display at Duxford.

[@skullsandstarlight]

The television show "Seconds from Distaster" did a great documentary on the Comet tragedies, as well as a detailed investigation of the cause of the accidents. Totally worth a watch if you've not seen it yet. By the way, I LOVE your channel! ♥

[@sandervanderkammen9230]

Well, they did a documentary... but not a great one, a lot of inaccuracies and unfortunately a heavy pro-british bias the is dismissive of de Havillands criminal negligence and attempts to cover-up evidence.

[@Paul-Nicer58]

​@@sandervanderkammen9230 ​@WilhelmKarsten Kharzeestan Krappenz DiktorBummer Jurkzxoffenz etc and co - they should note good with much awestruckness & extreme wonderment. *UPDATE MORE BREAKING NEWS ETC* *_It's interesting that some of the aircraft on the list should really have been noticeably safer than the Comet due to being a similar type but of much later design & manufacture but they definately were not safer._* How things were back then - *_Accident losses - % of aircraft built._* DeHavilland Comet 4 UK 14% DeHavilland Comet all mks 17% Vickers VC10 UK 5% *_The DH Comet had better safety than or similar safety to many other commercial passenger aircraft of a similar era_* Douglas DC-1 99% Douglas DC-2 47% Douglas DC-3 30% Douglas DC-4 26% Boeing s300 72% Boeing 307 70% Boeing 247 48% Boeing 707 20% Lockheed Electra Turboprop 29% Fairchild FH-227 30% McDonnell Douglas DC-8 14% Sud Aviation Caravelle 15% Canadair CL-44 Turboprop 46% Convair CV-580 Turboprop 22% A comparison of more recent aircraft. Accident losses comparison examples. 1970s - 1980s % of total Aircraft built Similar aircraft type, date / decade, useage, size. Biz Jets BAe-125-800 1.7 % Beechcraft Beechjet 400 2.2 % Cessna 550 Citation II 7.1 % Learjet 35 / 36 12 % Beechcraft 1900 6% Dassault Falcon 10 11.5% Aérospatiale SN.601 22.5% Medium size jets / Turboprops. BAe-146 5.1% Fokker 100 6% McDonnell Douglas DC-9-30 9.5% Fairchild FH-227 30% McDonnell Douglas DC-8 14% Canadair CL-44 Turboprop 46% Convair CV-580 Turboprop 22% Beechcraft, Fokker, McDonnell Douglass, Learjet, Fairchild, Aerospatiale, Canadair, Convair companies defunct. All Comets, including some Comet 1s, had full civilian use certification at some point after 1954, civilian use certification only being withdrawn after commercial flying stopped. Examples were flying until 1997 - one example did a signals research global circumnavigation flight series in 1993 via Australia virtually without a rest travelling 28000 miles, only had an ice warning indicator issue during the flights. *The DH Comet - World Firsts.* 1st gas turbine jet powered airliner. 1st high altitude 8psi pressurised full fuselage length passenger cabin airliner, not a trivial feature as structure strength required for pressurisation considerably exceeded strength required for normal flying stress. Nobody else had done anything similar before the Comet. The b-47 used 2 relatively small, heavily built pressurised modules (the aircraft where 6 had their wings fold up in 2 months while flying & some had their wings fall off while parked). The 1937 Boeing piston engined airliner pressurised passenger cabin was pressurised to 2 psi only - in fact that could easily be done as the normal unpressurized fuselage cabin structure strength for flying stresses only was all that was needed to be adequate so no significant weight increase issues needed addressing. 1st all hydraulically powered flying surface controls & actuators airliner with under carriage wheel disk brakes + ABS. 1st jet airliner to cross the Atlantic. 1st jet aircraft to do a world circumnavigation flights series. *Of course De Havilland had prior experience building many all metal construction airframe aircraft including thousands of jet powered fighter aircraft that were primarily of metal construction with pressurised cockpits & jet engines built by De-Havilland & we know the world's first all metal construction airframe airliner was built in England in the 1920s by Handley Page.* *_De Havilland did indeed always work to better than industry standards at the time, no evidence of negligence ever being produced in relation to the DH Comet._* The course of De Havilland & the general UK aerospace industry sector was not affected even slightly by the DH Comet. *_Other interesting World firsts_* *Vickers Viscount Turboprop Airliner 1947* *Gloster Meteor Turboprop Aircraft 1945* They might like to answer these questions. *Which airline has just ordered* *60 RR England Trent XWB Engines* *& What aircraft are the engines for?* _Bonus question for 10 points._ Which country has the *World's Highest Combined Per Capita* *Nuclear + Defence + Aerospace Sector Activity?* 👍 Cheers 🙂 . ... ... .. ... . ..... . . . . ..... . . . . xcvxzxccviviiiiicxvicvxiiivcxvv

[@adep6189]

The beautiful comet was way ahead of the field... The world lernt So many lessons from the British first jet liner, and the mistakes were paid for in Human lives 😢 brilliantly told , really enjoyed .. thx you . .

[@sandervanderkammen9230]

That's a completely false narrative, de Havilland was decades behind in aircraft technology and the real tragedy of the Comet Disaster was that it could have been easily prevented if de Havilland had simply followed well-known and understood industry standards used by other manufacturers.

[@birdbrain4445]

Really good and informative video. As a child, I had a bit of a fascination with planes. It was from a certain factbook I had on the matter, that I picked up the misconception that the Comet's square windows were the cause of its structural weaknesses, not the manufacturing process and materials used in combination with the altitudes it flew at. Putting that aspect of its design into perspective with other planes of the era, as well as why they were changed on later models, was a very effective debunking of it. So too was the mention of the Nimrod - I knew of the Nimrod too of course, but completely forgot that it was a Comet derivative/variant that flew without issue for decades. You learn (and indeed, re-learn) something new every day :)

[@WilhelmKarsten]

The Hawker Siddeley HS. 801 Nimrod is not a Comet, this is a common misconception. The Nimrod was designed by a different company decades later and has a different type certificate. There are no significant parts or assemblies in common between the Comet and the Nimrod, they are completely different aircraft.

[@birdbrain4445]

@@WilhelmKarsten I know; hence calling it a derivative or variant, as opposed to being the same plane. It is extensively modified from the Comet, but calling it derived from the Comet is a fair assessment imo.

[@WilhelmKarsten]

@@birdbrain4445 The Nimrod is a completely new aircraft.

[@Paul-Nicer58]

​@@WilhelmKarsten The original design for the Comet also took into consideration it's use as a military maritime patrol aircraft. A prototype of the Nimrod was being worked on before 1953 at Dehavilland.

[@sandervanderkammen9230]

​ *Here is the complete list of 39 Comet crashes and hull loss accidents.* G-APDN. 03.07.1970 G-ARCO. 12.09.1967 SU-ALD. 28.06.1963 LV-AHR. 23.11.1961 G-ALYP. 10.01.1954 G-ALYP. 02.05.1953 G-ARJM. 21.12.1961 SU-AMW. 19.07.1962 G-ALYY. 08.04.1954 SA-R-7. 20.03.1963 SA-ALC. 02.01.1971 CF-CUN. 03.03.1953 LV-AHP. 27.08.1959 G-APDH. 22.03.1964 XP915. 19.01.1971 G-ALYZ. 26.10.1952 G-APDL. 07.10.1970 F-BGSC. 25.06.1953 LV-AHN. 24.03.1970 SU-ALE. 09.02.1970 SU-ANI. 14.01.1970 OD-ADS. 28.12.1968 OD-ADQ. 28.12.1968 OD-ADR. 28.12.1968 G-ALYR. 25.07.1953 G-APMD. 16.11.1965 G-APMF. 05.11.1964 G-APDL. 23.12.1959 G-APDN. 09.03.1964 G-ARJN. 02.08.1963 G-APDF. 09.04.1959 XK663. 03.06.1959 G-APDM. 03.08.1962 G-APDA. 08.06.1959 G-APDB. 21.06.1959 G-APDM. 25.01.1961 G-APDB. 22.08.1960 G-APDS. 14.03.1960 LV-AHO. 20.02.1960