Well, doesn’t this disprove PHE?

Public Health England insists that we’ve an epidemic of child obesity:

A software mistake caused a Tui flight to take off heavier than expected as female passengers using the title “Miss” were classified as children, an investigation has found.

The departure from Birmingham airport to Majorca with 187 passengers on board was described as a “serious incident” by the Air Accidents Investigation Branch (AAIB).

Apparently not then. For if all were given that obese weight then this wouldn’t have happened, would it?

17 thoughts on “Well, doesn’t this disprove PHE?”

  1. There was an accident in America years ago where they hadn’t taken into account the change in body weight of people over the years. The FAA had made up some estimates in 1936 about average weights and hadn’t changed them or checked them until the crash in 2003. When they did update the averages, they found that people are 9kg heavier than in 1936 on average.

    https://en.wikipedia.org/wiki/Air_Midwest_Flight_5481

  2. That’s absurd… they literally have the date of birth (and legal gender one would assume) of every passenger available to them from the passport information. It would take a supreme idiot to try and infer this from other data, particularly as flight weight can’t really be calculated anyway until you know who is actually *on* the plane. There must be more to it than this… no one is that daft.

  3. Concorde: – “At the same time, the plane was operating outside its legally certified limits. When it stood at the end of the runway, ready to roll, it was more than six tonnes over its approved maximum takeoff weight for the given conditions, with its centre of gravity pushed dangerously far to the rear”.

  4. There must be more to it than this… no one is that daft.

    You haven’t met Indian* “coders” from the Bangalore Institute of Plagiarism, I see.

    No, obviously a spotty teenager programming a ZX Spectrum game in his bedroom circa 1985 wouldn’t be this daft, but Pajit got the job because he works for cheap and the guy hiring is his cousin.

    *Some Indians are brilliant techies, and great guys too, it’s the other 95% that are the problem. Their “coding” skills amount to lying about their experience, copying and pasting stuff they don’t understand from Github, and the culture of dishonesty and baksheesh in India makes it extremely difficult to keep out the hordes of frauds.

  5. An update to the airline’s reservation system while its planes were grounded due to the coronavirus pandemic led to 38 passengers on the flight being allocated a child’s “standard weight” of 35kg as opposed to the adult figure of 69kg.

    If the average weight of airline passengers is 69kg, why do the ones seated next to me always seem to weigh double that amount?

  6. Not an area I’m familiar with, but what consideration would cause anyone not to use full power on takeoff? Noise? Efficiency? And would a ton make all that difference?

  7. The programmer had been exposed to “woke” lectures that all adult females must be addressed as “Ms”. This post should be put in your “feminism” category.

  8. There’s this magic invention called a weight sensor. They’ve only been around, ooooo, five thousand years, so maybe thinking about fitting them to aeroplanes hasn’t trickled down into the aviation industry.

  9. @ rhoda klapp

    These days it’s definitely all about “Noise & Efficiency”. Many airports have strict controls on noise and approach/departure routes, and these require careful planning to meet. Fuel is probably the most significant cost for airlines, and so every effort is made to minimise its use. The pre-flight planning and data input to the aircraft’s Flight Management Computer will produce an optimum thrust figure for each individual flight. This includes the “calculated” weight, outside temperature, humidity & wind speed, runway length and density altitude, plus the climb out profile needed. A ton (or so) extra weight on a 70 ton plane isn’t going to make a drastic difference if there’s lots of runway available, but at a small regional airport it can become a serious matter. The crew should be paying close attention to the rate of acceleration and amount of runway being used, and always have the option of overriding the FMC to get max thrust, but with so much reliance being placed on automation these days that doesn’t always seem to happen.

    On the other hand, a good headwind and full thrust will get an empty Boeing 757 off the ground in 700 metres or so:
    https://www.youtube.com/watch?v=BVeC5bVBcic

  10. Regarding passenger weight.. ISTR that in “the good old days” check-in staff added an estimated weight to the passenger details as well as the weight of their luggage. Don’t they still do this? And if not, why?

  11. Thanks Dave. Although it seems just a little strange that such critical calculations are performed on imprecise input data. The weight you can certainly fix by going to full thrust if acceleration is slow, but what about the CG if that is also affected by the dodgy software? Or can they use U/C leg deflection to get that in real time? I vaguely remember that’s how you weigh and balance big aircraft.

    (I used to do this with small helicopters where CG is restricted to a range of a few inches. You hung the aircraft from a hook in the hangar and measured the inclination of the cabin floor then sat working it out by hand, no calculators or computers in thos days.)

  12. Exceeding the AUW increases the take-off run (especially if aborted), and risks overloading the undercarriage should an early landing be needed: fuel is dumped to get down to a safe weight for landing, which is much lower than the max safe for take-off.

    But the big danger is the CG: a bit forward, not really an issue, but too far aft and you have trouble with a capital T. Electrons (and muons) spin, commercial planes, preferably not. However, none of them can stop spinning.

    NB Part of my code was to pump fuel into the back of a commercial plane and determine when to stop. Pump too little, wastes money. Pump too much, new landfill opportunity in the Ruislip area.

    NBB I have deliberately spun a plane, solo, and I didn’t enjoy the experience. There’s a reason the final words of pilots is “Oaf!”

  13. “hadn’t changed them or checked them”: for Christ’s sake, had nobody noticed that lifts carry a little plaque implying that passengers will weigh an average of 75 kg? And then looked around?

  14. I wouldn’t have thought that CofG is going to be greatly affected by lard-arse passengers, as they are likely to be spread distributed around the cabin. But freight in underfloor containers is most definitely an issue. I’ve read reports of pilots having to abort takeoffs because the nose began lifting of its own accord, and a transporter crashing due to large items moving aft during takeoff, leading to an unrecoverable stall.

    There was a story from decades back involving (if my memory serves me correctly) an RAF De Havilland Dove which managed to get airborne with the elevator control lock still fitted! After that catastrophic blunder the pilot quickly redeemed himself, and got back safely by organising the passengers into a closely packed standing group, and telling them to move back & forth in the cabin when instructed. This was enough to enable him to level off, descend, and then flare when landing…

    “Critical calculations are performed on imprecise input data”

    The legendary “Gimli Glider” incident (involving a B767 running out of fuel) was partly due to mixing up pounds & kilos, when metrication was being introduced.

    “Part of my code was to pump fuel into the back of a commercial plane and determine when to stop”

    IIRC Pumping fuel back & forth was critical in the Concorde, and was the only way they could get it to go supersonic and back again. If this system had ever failed at Mach2 the plane was doomed…

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