Southwest Airlines suddenly grounds scores of planes due to aircraft weight issues
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I am convinced the biggest risk on aircraft weight remains the under-calculation of pax + carry ons. This despite the recent mandated FAA et al increases.
In 2013 the H&S dept of our N. Canada mining operations did a full verification of our rotational personnel. Yes, these flights were over 80% male and miners are probably larger than the average male, but....
The result???
Summer 278 lbs.
Winter 291 lbs.
Enter those kind of figs into the last Weight & Balance you personally calculated and you'll see where I'm coming from.
In 2013 the H&S dept of our N. Canada mining operations did a full verification of our rotational personnel. Yes, these flights were over 80% male and miners are probably larger than the average male, but....
The result???
Summer 278 lbs.
Winter 291 lbs.
Enter those kind of figs into the last Weight & Balance you personally calculated and you'll see where I'm coming from.
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I think the discussion about the Irish VLCC was something along the lines of as long as they were flying comparatively shorter stage lengths and so were rarely carrying full fuel then it could be that the aircraft never departed at the manufacturer's MTOW....Or something like that....
But as I said, just a thought...
.
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No idea if the numbers are standard around the world. The FAA raised the numbers several years ago after a Beech 1900 crash in CLT. They said they would monitor American weights and adjust as necessary.
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Did we not have a discussion on here a couple of years ago about the Irish VLCC ' gaining advantage ' by registering some / all its fleet with lower gross weights in order to benefit from lower En Route Charges from Eurocontrol ?
Lowering the max TOW is standard practise at klm as well. There are scores of 737’s with a max tow of either 70t, 71t, 72t, instead of the official 73,8t. (-800)
or 61t for the 737-700, which is officially 64.something. Saves a huge amount of hard cash.
not only RYR does that.
or 61t for the 737-700, which is officially 64.something. Saves a huge amount of hard cash.
not only RYR does that.
A few years back one of the UK locos ran an exercise to check the accuracy of their weights. Aircraft were weighed in the hangar during maintenance to verify actual weight against the recorded figures and also selected at random as they entered the apron after a flight and directed onto a stand equipped with pressure pads. They were marshalled carefully onto the three pads and after about a minute, if even that, were able to disembark pax normally. Results were correlated with the flight papaerwork and processed.
Results showd the standard weights used were remarkably good, iirc something like a 2-300Kg deviation from the paper figure which on a 60t aeroplane is extremely accurate.
Results showd the standard weights used were remarkably good, iirc something like a 2-300Kg deviation from the paper figure which on a 60t aeroplane is extremely accurate.
Southwest 737 Short Grounding in September
Temporary grounding of 115 737-800 at Southwest took place due to weight difference of 75lbs in IT vs. actual mass. Took some days until half of the fleet returned to service. Reported to be a difference <0.05% of MTOW.
from aero international magazine
Safety matters, but isn't this a bit surprising?
from aero international magazine
Safety matters, but isn't this a bit surprising?
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As to how it happens - weight may "accrete" on an air frame, as things like passenger wi-fi, or even flight systems, get added or upgraded (or even removed). And maybe not all departments "get the memo" of the change to aircraft N000SW's weight, so the records don't match. Big corporate bureaucracy (or perhaps too small and overworked a corporate bureaucracy).
Ummm...isn't that the point of using an average weight? If 50% are over the average, the other 50% can only be less than the average. So all is OK.
Just sayin'.
The real problem is that frequently it's not 50% who are fatties and over the assumed average weight, it's 80%, especially when they lug on board 25 Kg of "cabin baggage" that no aircraft is designed to accommodate.
Just sayin'.
The real problem is that frequently it's not 50% who are fatties and over the assumed average weight, it's 80%, especially when they lug on board 25 Kg of "cabin baggage" that no aircraft is designed to accommodate.
Lowering the max TOW is standard practise at klm as well. There are scores of 737’s with a max tow of either 70t, 71t, 72t, instead of the official 73,8t. (-800)
or 61t for the 737-700, which is officially 64.something. Saves a huge amount of hard cash.
not only RYR does that.
or 61t for the 737-700, which is officially 64.something. Saves a huge amount of hard cash.
not only RYR does that.
On the Airbus, you have multiple WVs.
Originally Posted by txl View Post
Interested PAX here. I always wondered what the average figures for calculating passenger weight are. Is that a global standard?
Interested PAX here. I always wondered what the average figures for calculating passenger weight are. Is that a global standard?
https://tc.canada.ca/en/aviation/ref...-ac-no-700-022
andrasz
Had some 727s at an old job, exNW airframe converted freighters, the landing weight had purposely been lowered to reduce the landing fee paid. We sent a check to Boeing and in a few weeks had new placards raising the max landing weight 4000 pounds.
Had some 727s at an old job, exNW airframe converted freighters, the landing weight had purposely been lowered to reduce the landing fee paid. We sent a check to Boeing and in a few weeks had new placards raising the max landing weight 4000 pounds.
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I remember several years back taking a co-worker to the airport for a flight to Sydney on a very small airline. Earlier that year they had experienced a fatal crash. One thing I had never seen before was weighing each passenger and when everyone was checked in, assigning seats. Second was that the pilot got a fuel sample from the fueling truck, took it into a back room, and after a few minutes came out and gave the fueler the okay to proceed. Too bad it took a crash to tidy things up.
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txl No here is not a global standard; there are 'regulator' standards and should an airline choose to do so, they can seek approval for their own standard passenger and baggage weights. There is a strict process and mathematical model behind the derivation of the standard weights published, used and approved. Typically they are derived from a study of real passengers (actually weighing many hundreds if not thousands across a population at the aircraft side, including all hand baggage) and the numbers run through standardisation methodologies with a confidence interval of 98%. Meaning that the average weights applied for Male, Female, Child and Infant (including hand baggage) is accurate to within +/- 1%. Same for those that use a standard, as opposed to actual, baggage weight for mass and balance calculations prior to a flight departure.
Last edited by Icarus; 21st Oct 2020 at 01:28.
