Incorrect weight calculation 737 3

[LittleInch]

This report has just surfaced

https://www.theguardian.com/world/2...miss-on-board-child-weight-birmingham-majorca

Basically the load sheet allocated a childs weight to everyone listed as "Miss" instead of an a adult weight for everyone with "Ms". Apparently caused by a revised IT program in an unnamed other country where miss is commonly used for children.

Now something the size of a 737 it may not have been a huge issue, but I'm sure I recall a smaller commuter plane of 20-25 people which stalled on take off and when they recalculated all the Actual weights of the passengers the plane was over weight. US airways flight 5481 -

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

https://admiralcloudberg.medium.com...crash-of-air-midwest-flight-5481-caa032313df6

Other things contributed more to that crash, but overweight without realising it was a major contributory cause.

So maybe not an engineering disaster, but a near miss and is a reminder than generic assumptions still need to be checked against your specific design or operation.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[JohnRBaker]

My father-in-law flew C-47's (AKA DC-3) in Europe during the war. One of his missions was delivering gasoline to Patton's army. They would load 55-gal barrels, and as he described it, if you could get it through the door, they could take off.

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[dik]

My dad was with the RCAF during WW2 and he told me some real strange stories about how this craft was used/abused...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[dik]

I just realised, for the load to shift, there was still room for more... maybe, therein, lies the problem.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Alistair_Heaton]

You can over load them. But it takes a whole heap of fuel to be loaded.

As per the load shift example it more usual to have issues with trim outside the envelope.

Hot and or high short runways with performance limited then over loading is an issue. Dubai the loose 10 tons if they take off at mid day in 50 Deg C

There is a difference between structural and performance overloading.

 

[dik]

Thanks... was only joking about overloading... but the DC-3 seems to accommodate it well... If it takes off... you can likely fly and land it... often runways in small areas are on a sloped surface and short to help with the take-off and landing... assuming going in opposite directions

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Alistair_Heaton]

Dc3 isn't pref A which are certified to fly on one engine including climbing.

You loose 60% of your performance single engine.

You can get away with murder overloading multi engined fix wing until an engine fails if you have a long runway. .

Helicopters even an extra 50kg can be fatal.

A previous company I worked for operated the daks for oil spill spraying in uk. They used to land them on beaches and all sorts.

 

[Alistair_Heaton]

This one came up today from one of the techs have a guess what caused it to get into that state

 

[JohnRBaker]

Problem while fueling...

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[Alistair_Heaton]

Yes while fueling after sealing the tanks and forgetting to open the vent vales.

Blew the central tank in the wing box

 

[Lou Scannon]

Seems like a case for a pressure relief valve somewhere, maybe near the pump

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[1503-44]

Vents are pretty good PRVs... if they're open.

 

[Alistair_Heaton]

They physically block them I believe doing the tank maint stuff.

The fuel Bowsers pump at about 3 bar normally. Min pressure of the fuelling system to work is is 2 bar.

 

[Lou Scannon]

second thoughts, near the connection to the aircraft tank, lest the tank put up too much resistance... but that would require a fuel return hose, dunno if that is already there.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[Alistair_Heaton]

The is nothing the bowser either pumps or suck fuel out.

At the end of each wing there is an expansion and a surge tank which is vented to the outside via a ram jet vent. Which gives the tanks a positive differential in flights.

If anything goes wrong with fueling you end up with a jet1fall at the wing tips. You always know the new refuelers because they park under the vent.

 

[Lou Scannon]

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz