Why don't aircraft weigh themselves?

[ppppilot]

OK Gents. What are you afraid of?
JT. A thread like I am proposing it would be vary in relevance from as much as a small grain of sand to nothing, depending on the interest shown by our colleges. Not too pretentious. Only trying to be a sign of our interest on to not forget a safe and useful device like OBWABS.
Actual OB weighting systems can be expensive or inaccuracy mainly because no one gives a penny to investigate. The fuel metering device, at its beginnings was a cork and a lever with a variable resistor.
Don’t all of you agree that weight procedures are archaic? How can anybody accept to load a 747 with the weight given by the person that pays for that weight? When I flew cargo I remember to discover at the arrival very dangerous goods camouflaged into a printer package. If the sender do that what is he expected to do with the weight?
How can anybody accept at the actual stage of technology, lets say?... Ok women weights in summer 81 kg and 83 in winter and men 91 kg and 93… And transsexuals? Same at Congo than at Minnesota? Very complicated, best 84 kg for all. Sign it like that and lets celebrate with scotch all night long.
Is there any regulation on checking the weighing equipment at the check-in desks or the pallets scale since the day they were installed there?
But all of us accept go to the limits with performance, using software programs to use the last millimetre of the rwy for TO.
Mutt. If you are talking about behave like an ostrich by the time their pilots are dealing with an overloaded airplane, in my opinion those airlines shouldn’t to exist. Same opinion than CAA, FAA, AAA, and all the A’s over this world and the others. But if you are talking about serious airlines I believe that of course they do like to know the exact weight on the plane, because that weight means money. Money out or money in. I am sure that I am carrying thousands of kg for free. Nobody pays for them, because nobody knows that they are there. That’s money out. The extra fuel for that extra weight is money out. Serious airlines don’t play with its future. I have seen to my company very few times going to the limits and for example when I had to TO into a “tropical storm becoming a hurricane”, they gave me a million of analysis for TO with max pax possible. I took the more conservative and from there a couple of tons down, just in case. Specially because I am not comfortable with the weighting systems at those funny destinies. That is money for the company. I know, and far away also my money. None of my bosses told me a word, because they would acted the same. They do want nobody playing with their future.
In my experience the bigger the airplane the most usually limited at ldg. The smaller at TO. Probably that depends on the plane and the range of flights. Mine is 275t MTOW, 178t MZFW, 190t MLW. That makes 97t of fuel from where I have TOW limitation and that means over 15 to 16 flight hrs. My flights are maximum 11 hrs. In that situation only will be a security margin to performance calculation. That would be the primary use I would like to use it. Always using the bigger numbers from the loadsheet and WABC. My company use to give me 10 tons margin at 190t Ldg. I adjust it to 3t. That is a more than 1,5%.
I understand you are saying that some airlines doesn’t want to have such a system in their airplanes because of maintenance cost and inaccuracy? I better would say that companies would like the OBWBS but at a state of no significant maintenance cost and a level of accuracy of 0,1%. What they do not want to pay for is the cost of investigation to obtain such a system. Those are economical facts. Therefore airlines are defending money. As a pilot I am talking on behalf not only money but my life also. That’s safety and what I am trained for. So Mutt my opinion is, we both pilots and companies must have the same relevance on designing the airplanes and their systems. I think both positions are important and direct related. There it goes a couple of examples that I personally know.
At my very beginnings I flew in an aerial photography company. The most beautiful job I have ever done. I became Director of Operations and then I was all the time fighting with the boss (owner).- Fly lower, photos are better…No I don’t.- That other company has bought the engines half of the price than you did… That other company stopped that plane one month later burning more oil than fuel. Etc. I was 8,5 years and we broke all benefit records without a single incident. Then I decided to leave that beautiful job to live the beautiful live the airline pilots do. They took a pilot well experienced 5 years flying the same job and same planes. Unfortunately less than a year later he crashed one of the planes into a roof half an hour from TO full of gas. The fire was so heavy that not a piece of the pilot and photographer bodies could be found, except teeth. 3 years later that company didn’t exist anymore. Boss or pilot guilty? Both in my opinion.
The second example, all of you have been talking about it here.
IB overrun at Quito. Crazy airport. 92000 ft elev. Surrounded by 15000 ft mountains. Bad weather, worst ATC. 2600m LDA downhill slope, nobody knows the real elev since last time they took off the rubber of the rwy. ILS displaced from PAPI. 182 gs at touch down with high pitch attitude. A340 Flap limited at 20000’, select 1 at 15000, 2 at 13000 and then turn 200º to final app. Better maintain selected speed at least 10 knt faster at the beginning of the turn… Crazy.
Everybody knows what you read or you hear, but you also must know that initially IB was flying the A340-300. When the plane began to be full and the company was loosing pax they decided to fly the A340-600. On the papers it is perfectly possible. But Spanish pilots are not better nor worst than the rest and our maximum aspiration is as yours, get to retire with no incidents. 250 tons at ldg with those conditions is going to the limit. So IB pilots recommended many times to the company not flying the 600 there. Daily frequency, thousands ldgs with no problem, but everyone can have a bad day and better not be at the limit then. The rest all of you knows. Today the 300 is back flying to Quito.
By the way, about good clue of how hard it landed last night. Do you know there is an Airbus maintenance program that any airline may subscript? The bus ACMS reports via ACARS to the company exceeded parameters, included G at LDG. If you are in the program that ACARS is also sent to Airbus. At airbus they investigate the causes, the solution and if the company has the spare parts in the stock. It is supposed that only if you contract that. But I know a guy, flying for a company out of that program, who landed an A330 somewhere at South America the same sweet manners than a rugby player giving the welcome to the opposite having the ball. The crew didn’t say a word of that and when the plane arrived back to its base, Airbus phoned to the company to stop that plane.
Hey, this seems closer to be one of those disregarded accident analysis than a post. It is too long to read it again for mistakes. I hope all of you will send corrections for me.
Tailwinds