Thursday Open Skies Thread

British de Havilland Comet, the First Commercial Jet Aircraft in Aviation History

and Why Airplanes Don’t Have Square Windows

On May 2, 1952, the first commercial jet flight in history departed London for Johannesburg, South Africa, a British Overseas Airways Corporation aircraft.

On May 2, 1953, one year to the day after the maiden flight of the British-made de Havilland Comet, aircraft G-ALYV departed Calcutta Airport for Delhi as BOAC Flight 783. A few miles out of the airport, the flight encountered a severe thunderstorm. While the pilot and air traffic control were both aware of it, the storm did not appear severe enough to restrict flight through it. Furthermore, the captain was well-qualified, had considerable experience on this route, and had experience in similar weather conditions. Just six minutes after take off, while climbing to 7,500 feet, radio communication was lost. About this same time, witnesses at various ground locations saw “an aircraft coming down in a blaze of fire through severe thunderstorm and rain” and then crash into the ground. All 37 passengers and six crew members were killed.


The most notable lesson learned from the Comet disaster is that viewing windows are no longer designed square but with rounded edges to reduce any stress concentrations. Another immediate lessons is that crack-stoppers are now placed between frame-cutouts that take the shape of circumferential stiffeners that break-up the fuselage into multiple sections and thus prevent the crack from propagating from one window to the next. Most importantly however, before and during the Comet era the aircraft design philosophy was predominantly SAFE-LIFE, which means that the structure was designed to sustain the required fatigue life with no initial damage and no accumulation of damage during service e.g. cracking (1). The Comet accidents showed that around stress concentration cracks would initiate and propagate much earlier than expected, such that safety could not be universally guaranteed in the SAFE-LIFE approach without uneconomically short aircraft service lives.

For this reason the FAIL-SAFE design philosophy was developed in the late 1950’s. All materials are assumed to contain a finite initial defect size before entering service that may grow due to fatigue loading in-service. The aircraft structure is thus designed to sustain structural damage without compromising safety up to a critical damage size that can be easily detected by visual inspection between flights. All inspections are coupled with crack propagation calculations that guarantee that an observed crack is not susceptible to grow to the critical size between two inspection cycles, in which case adequate repair is performed. Furthermore, the structure is designed to be damage tolerant with multiple load paths and built-in redundancies that impart residual strength to the aircraft in case the primary structure is compromised in-service.

A couple of weeks ago, I turned 65 and it is still astonishing to me the entire history of commercial jet aviation has taken place in my relatively short lifetime.  The first flight took off just 85 days before I was born.  Nine years later in 1961,  Shannon and I took our first flight on a jet to Dallas to visit our uncle and attend the grand opening of Six Flags Over Texas.

From that one single jet flight leaving London in 1952 to over 100,000 flights each day around the world.

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66 thoughts on “Thursday Open Skies Thread

  1. ….Heaven forbid a group of Americans band together to improve their quality of life.

    But surely you’ll admit that there is always the risk, at some point, of an elite group of Americans banding together to improve their quality of life at the expense of non-elite Americans whose quality of life doesn’t improve.

  2. Thanks again to Darren for bringing Mrs. Bonecrusher back home safely from IAH. If you are going to be gone for more than a couple of days, using Darren’s Taxi Service to the airport and back is the best, most convenient way to go.

  3. It looks like there could be a new space satellite race and Super Dave will never be able to retire.

    HEADLINE: China Focus: China’s satellite sends unbreakable cipher from space
    BEIJING, Aug. 10 (Xinhua) — Chinese scientists have become the first to realize quantum key distribution from a satellite to the ground, laying the foundation for building a hack-proof global quantum communication network.

    The achievement based on experiments conducted with the world’ s first quantum satellite, Quantum Experiments at Space Scale (QUESS), was published in the authoritative academic journal Nature on Thursday.

    The Nature reviewers commented that the experiment was an impressive achievement, and constituted a milestone in the field.

  4. Re train horns. In Sugar Land the horns are part of the cross arms. I had not thought about it, if the train itself still sounds off. You hear the horn, the ears say a train is there, but it takes a few seconds before the train shows up.

  5. The British de Havilland Comet story always interested me and the square windows may be the main reason that the Boeing 707 became the first jet used by most carriers. A lot of people may not know it, but the British were ahead of the rest of the world, (including Germany) in the design of reliable turbine engines. If memory serves, they had a workable engine in the 30’s. My first good paying job was with a small Commuter Airline in Georgia and we had 7 Beechcraft B-99’s powered by the bullet proof, Pratt & Whiney PT-6 turboprops and 3 Fairchild F-27’s powered by the reliable “old school”, Rolls Royce Dart. The Dart was the first turboprop ever to be used in an Airliner, a Viscount with this engine first flew in 1948.

  6. 4

    But surely you’ll admit that there is always the risk, at some point, of an elite group of Americans banding together to improve their quality of life at the expense of non-elite Americans whose quality of life doesn’t improve.

    Of course. You can count on it.

  7. China couldn’t even stabilize a satellite in orbit until they started donating to the Clinton campaign.

  8. Good morning Hamsters. So we slog on through August in search of a glimmer of a cold front just waiting to bust out of the Arctic and come this way. We can dream, can’t we?

    With so much apparent Lefty upset over Dunkirk, which we will eventually see at home, not in a theater, its immense importance must not be denied in terms of desperation resulting in salvation for thousands of troops.
    Dunkirk made D-Day possible.

  9. Well, this is different….frightening…interesting: Using DNA to hack computers.

    In what appears to be the first successful hack of a software program using DNA, researchers say malware they incorporated into a genetic molecule allowed them to take control of a computer used to analyze it.

    The biological malware was created by scientists at the University of Washington in Seattle, who call it the first “DNA-based exploit of a computer system.”

    To carry out the hack, researchers led by Tadayoshi Kohno (“see “Innovators Under 35, 2007”) and Luis Ceze encoded malicious software in a short stretch of DNA they purchased online. They then used it to gain “full control” over a computer that tried to process the genetic data after it was read by a DNA sequencing machine.
    The researchers warn that hackers could one day use faked blood or spit samples to gain access to university computers, steal information from police forensics labs, or infect genome files shared by scientists.

    For now, DNA malware doesn’t pose much of a security risk. The researchers admit that to pull off their intrusion, they created the “best possible” chances of success by disabling security features and even adding a vulnerability to a little-used bioinformatics program.

    The new DNA malware will be presented next week at the Usenix Security Symposium in Vancouver. “We look at emerging technologies and ask if there are upcoming security threats that might manifest, so the idea is to get ahead,” says Peter Ney, a graduate student in Kohno’s Security and Privacy Research Lab.

    To make the malware, the team translated a simple computer command into a short stretch of 176 DNA letters, denoted as A, G, C, and T. After ordering copies of the DNA from a vendor for $89, they fed the strands to a sequencing machine, which read off the gene letters, storing them as binary digits, 0s and 1s.

    Erlich says the attack took advantage of a spill-over effect, when data that exceeds a storage buffer can be interpreted as a computer command. In this case, the command contacted a server controlled by Kohno’s team, from which they took control of a computer in their lab they were using to analyze the DNA file.

    Companies that manufacture synthetic DNA strands and mail them to scientists are already on the alert for bioterrorists. In the future, the researchers suggest, they might also have to start checking DNA sequences for computer threats.

    The University of Washington team also cautions that hackers could use more conventional means to target people’s genetic data, precisely because it is increasingly appearing online…

  10. The electric train on Scott St, same thing. Horns are part of the crossing, and she don’t make no smoke.

  11. #7 Hamous:

    So how does this Uber thing work? Do you get to pick your driver? I’d throw some business Darren’s way when I travel.

    Call him directly and make your deal. This will be off the books and he doesn’t have to share the proceeds.

  12. and she don’t make no smoke.

    But if you laid a nickel on the track it wouldn’t smash it flatter than a dime. It’d probably derail the train.

    As a semi-frequent rider of the toy train, I can attest they do have horns of sorts. They have the ding-ding-ding trolley car noise. That one makes me start singing ♫ Rice-a-roni, the San Francisco treat! ♫ Then, at intersections with an arm they have an artificial steam engine-sounding horn.

  13. Morning, chickadees.And hamsters, of course. Seeing my periodontist this morning, so I need to leave time for a super good brushing before I head his way. Taking a shopping list for just in case I have enough pep left after the appointment to get some chores run.

  14. Morning all. The neighborhood skunk is still at large, having evaded the trap once again last night. Apparently no other varmits took the bait either as it was still there this morning. I was considering mowing the lawn today, but I think I’ll just let it grow on out a little more. Still trying to keep it from completely burning up from the heat. The cooler mornings the last day or so have certainly been welcome. Last night’s baseball game between the Cardinals and the Royals, played in Busch Stadium, introduced a new character into the annals of baseball history – the Rally Cat. I’ll see if I can find a video later to post, but basically, a young cat took off across the field during the game to the delight of the 40,000 plus fans in attendance. The groundskeeper finally caught up with kitty, picked it up, and headed off the field. It wasn’t long before he (the groundskeeper) started making faces and shouting out something that looked like it included the word “ouch.” The cat scratched and clawed and bit all the way back, but the brave groundskeeper never let go, despite his obvious pain. Once the game resumed, the Cardinal catcher hit the first pitch over the left field wall for a grand slam home run – thus, the legend of the “Rally Cat” was born. Film at 11.

  15. Re train horns in Sugar Land, I think I heard the tracks along 90A had gone to QUIET ZONE mode sometime in the last 10 yrs or so. I once stopped just off 90A to rescue a snapping turtle that was heading downslope from the tracks toward the highway. I had just picked him up by the edges of his shell when a train blew by, deafening me with full-on up-close exposure to the horn blast. I put the turtle on the floorboard of my old pickup and drove him down to the city park a few blocks away — set him loose headed away from the highway.

  16. I was so exhausted yesterday, trying to operate on only a few hours’ sleep. I was grateful that there was no raccoon party going on overhead last night…that I heard. I slept like a rock, and woke up this morning to quiet again. Thought all the raccoons were gone…but I heard one sound this morning, so not all have exited the one-way door that our pest control guy installed. He said it might take a while. We did trap a squirrel on the trap on our roof, though. I guess he’ll come by today and release the tree rat.

    MIL looked exhausted last night when I picked her up. They gave her magnesium on Monday. She said she usually feels her energy level perk up when they do that, but not this time. She said she did okay yesterday, until the time they released her and then the fatigue hit her. She looked so tired I actually asked if she wanted me to come in and help her get situated in her house; she refused the offer. Hubby picked her up this morning for her biopsy and he said she looked really tired this morning, too.

    The past chemo treatments were a piece of cake. This one, not so much.

    She originally told me I’d have next week off the chauffeur duty, but she said last night that they were making decisions and may continue treatments next week.

    If’n you’re so inclined, a few prayers for her couldn’t hurt. She’s not a praying woman, so it’s up to others to help her out there.

  17. There’s no restriction on how long the engineer blows the horn as long as he blows it three times approaching the crossing. There’s a rumor of an engineer whose ex wife once lived near the tracks.
    He made sure she knew when he was passing through, laying on that horn for a long time.

  18. My friend who has a camphouse that I’ve been known to haunt lost his sister in a train collision. Her driveway was an unprotected crossing, a couple of miles south of Bellville. She never heard the horn.

  19. BCS was driving me back from church one morning, and our usual route took us by what used to be some kind of metal fabrication or foundry structure, which had a rail track running right by it. We were in a tiny little Toyota car, talking away, and I swear we both looked up and down the rails before she drove over the tracks. There were no arms, so we knew to always look.

    We almost came out of our seats when the train horn sounded RIGHT BEHIND the car. We must’ve missed it by inches. She and I looked at each other, white faced and in shock, and asked how we could’ve missed seeing it.

    I’m sure that engineer was changing his shorts at the next stop, too.

  20. #29

    I saw that. Made me cry. I don’t know why I feel such a connection to a singer; I normally don’t feel so sad when a celebrity passes.

  21. Texpat says:
    AUGUST 9, 2017 AT 8:29 PM


    What are they going to do the fairground dance hall ? I hope they don’t ruin it with some fancy 21st century ideas.

    The Hysterical Society is one of the movers of the project and probably would shoot down any stupid changes. Air conditioning will be added since it is unusable five months of the year. Modernizing the kitchen is a priority. The giant windows need to be replaced. The beautiful wood flooring is in surprisingly good shape and will be refinished. Lighting upgrades, etc.
    We don’t really have a meeting room of that size and it is currently a non-performing City asset. It will be perfect for wedding receptions and intimate concerts.
    When I had grand visions of bringing in Shake Russell for my 25th anniversary, I was going to use it for the venue.

  22. Yeah, they should probably bulldoze the damn thing along with the veterans memorial next door. Put a couple of goats out there to keep it mowed down.

  23. My #34, Our hanger was the one with the rusty roof and if you place your little Google Man on the second Gary, of Gary L Moore Ct, just off Demere Road, you can see the 10X10 door that was added after Mike Parneviks drove the Tug through the wall.

  24. If I understand the way things work, it’s going to cost a fortune to renovate that place because it has to retain a lot of its historic features. I’m not saying tear it down, but I would suggest that the plans and budgets be carefully reviewed before committing.

  25. I remember the antique shows they used to have in that venue. Lotsa money passing through town during those things. The Round Top antique thing is moving towards Belleville. A town filled with fat wallets once a month a good idea

  26. Rush is on fire about the NYT and WaPo and the alphabet wetnerks digging up old stuff and presenting it as breaking fake news. We’ve known about the Norks and their nukes for a long time, old news. And the global warming and sea level fake news has been out for 6 months, which apparently the NYT corrected itself in great chagrin and in small print but is still pushing.

    Libs are trying to whip up panic. Including the shocking news that President Trump has the nuclear codes in the football. Oh, no, this is tragic according to the lunatic left. Never mind that all the presidents since WW2 have the football or its equivalent nearby all the time, including that fool Obama. BTW, where is Obamaramadingdong these days? Figured he’d want to be front and center 24/7.

  27. Having a historical marker on private property generally doesn’t come with long term State involvement, but since the dancehall is publicly owned by the City it falls under the State Antiquities Code administered by the Texas Historical Commission. The Feds may even get their grubby hands in on the act.
    Hiring the approved historic preservation consultants will jack the price a lot.

  28. Gymnastic Socialists

    These German practitioners of a gymnastic system begun in 1811, Turnverein societies were prevalent across the nation at the time and members were all part of the larger national American Turnerbund (gymnastic league). The league, or federation, once held over thirty thousand members and advocated a variety of causes including abolition and socialism. Shortly before the construction of the Bellville’s Turnverein Pavilion, the national league made as its primary goal the introduction of physical training, including gymnastics and calisthenics, into the American school system. Their social halls, including Bellville’s pavilion, provided plenty of room for gymnastics as well as dances, meetings, and celebrations. In time, the Americanization of Turnverein societies included a de-emphasis on gymnastics, replacing it with a sport requiring somewhat less vigor – bowling.

    The best photo of the dance hall I could find:

  29. Back home with a dental report no different than if it weren’t 2 months late because of my “light duty” season. I did a terrible job of trying to brush and floss for first month after my surgery. And didn’t even try to use the Water Pik because it’s impossible without a pretty good lean-over. Then at the end of the second month back home, my Philips Sonicare toothbrush lost several of its programmed functions — first to go was the Gum Care setting that I bought it for. I continued to use it for a couple more weeks, until one day all the settings were dead. I had to use a manual toothbrush while I waited for the new Sonicare I ordered to arrive.

    Around the same time, my Water Pik sprang a leak and quit pumping. Fortunately, I had a spare I had bought for Hubs, who never even unboxed it. He uses an Oral B electric toothbrush and floss picks, but was done with Water Pik-ing. So that was conveniently available for me.

  30. If Shannon steps up on a table with a beer stien in one hand and a Luger in the other, firing it into the ceiling and calling for those folks in that EDC thing to march on the county courthouse, I’m gonna apologize to El Gordo

  31. Talked to a friend of mine last night. One of those “We don’t talk for months and it’s like we never stopped talking” kind of friends. He’s a great graphics artist, does cars and just about everything else. He’s excited about a possible new project – one of those 3D floors (and he’s insisting on a wall, too) for a local car dealership.

    If y’all are looking for an artist, I can hook you up with a phone number for the guy. He has a FB page – “Bad Apple Grafix” if you want to see some of his work.

    BTW – I love how he does flames. I see “flames” on some of these show cars and roll my eyes. His are realistic flames. Way cool.

  32. Look up toward the heavens each night
    When the stars seem to shine
    By the same stars above you
    I swear that I love you
    You are my pretty Fraulein
    When my memories wander
    Away over yonder
    To the sweetheart that I left behind
    In a moment of glory
    A face comes before me
    The face of my pretty Fraulein

  33. We’ve got 83 and it’s miserably mugly this evening. Bring on September. Please.

    One of those days when I’ve got a glass half full of root beer and was gathering the waste basket contents for tomorrow’s trash day. Set the glass down somewhere along the way and finished the route with full trash bags. Put the bags in the big trash container in the garage ready to haul out to the road tomorrow morning.

    Back in the house. Where did I leave that glass? Two circuits around the house and it remained missing. Phooey, can’t waste more time looking for it.
    Get another glass and pour in root beer. No sooner done than I find the missing glass sitting on a bookcase in a room I searched not 10 minutes before. Solution: Empty the first glass into the new glass and put the first glass in the dish washer.
    And go on about the evening’s activities.

    Bet everybody who reads this has had a similar experience with misplacing something.

  34. El Gordo says:
    AUGUST 10, 2017 AT 4:49 PM
    #47 – Fer what?

    For doubting your doubts on the Schannon EDC thing.

    It wasn’t until Schannon revealed the whole Socialiast Bund thing that it all fell into place.

    Here you have a group of people with access to taxpayer funds who are unelected. That alone is cause for concern, but then you realize that one of their “issues” involves cooperation with a shady bank, combine that with the knowledge that they not only have intimate knowledge of the intricate traffic patterns of the Austin County seat, but the means to control the entire city. Large curbside planters become barricades. Giant concrete heads become rallying points. Vertical flags become signalling devices.

    But the big thing, the one that brings all the pieces of the puzzle together, is their effort to bring silent trains running through the town. Don’t you remember how the Kaiser engineered the Bolshevik takeover of Russia? The train, man, the train! He put Lenin on a sealed train straight into Russia and nobody knew he was coming. The silent trains can bring in reenforcements from Sealy and Columbus, and more importantly, the personage who will end up controlling the whole thing.

    Its obvious now, isn’t it? Schannon and his brother are engineering the take over of Austin County and installing a monarchy in its place. They’ve been plotting for decades to put a Jewish Princess on the throne of this new monarchy.

    And if I don’t get appointed Secretary of Defense (or Lord or Duke or whatever), I’m spilling my guts to the press.

  35. C’mon guys. They’ve been prepping the battlefied for years. “La Princessa” this and “Her Majesty” that—getting us used to the idea so we can be used as pawns later.

    The whole idea that some Bavarian fitness fanatic bund magically transformed itself into a bohunk bowling league is ludicrous and has “coverup” written all over it.

    And Schannon in control of the water distribution.

    That’s how they’re going to get the halucinogenics into the population.

    That and the Kolaches at Newman’s.

    C’mon guys—Newman lives in a freaking castle. You think he built that for himself?

  36. Grim news tonight from NOLA on the 10 pm news. The heavy rains that flooded parts of the city this week have not yet been pumped away, leaving stagnant water in channels. And today the power station that runs the pumps caught fire and was out of commission for a while.

    Ya think this is gonna limit visitors to NOLA until this situation is cleared up? If this situation ever gets cleared up.

  37. Adee says:
    AUGUST 10, 2017 AT 10:43 PM
    Grim news tonight from NOLA on the 10 pm news. The heavy rains that flooded parts of the city this week have not yet been pumped away, leaving stagnant water in channels. And today the power station that runs the pumps caught fire and was out of commission for a while.

    Ya think this is gonna limit visitors to NOLA until this situation is cleared up? If this situation ever gets cleared up.

    That’s OK.

    Moon Landrieu took those statues down.

    So, its all good.

  38. Rocket update

    They were able to remove the two chest tubes he had and he was more responsive today. Surgery for his lower facial fractures is currently scheduled for tomorrow.

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