W&B and baggage

Rosstafari

Rosstafari

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Menzies handles our ground stuff here in SEA. Last night, they forgot to load an entire cart of baggage onto a flight, not realizing it until the plane (A320) was in the air, which got me wondering how crucial that is when it comes to maintaining proper weight and balance. So, a few questions:

1. You have to be pretty anal when doing your W&B calculations on the little single engine pistons. How about on airliners? I know there's a lot more power and room to spare, but I have no idea how much. Even with 55 bags missing, I figure it's not enough to throw it off... but how much would be?
2. How noticeable would that've been on takeoff? I'm not sure what compartment they were missing from, but is that the kind of thing you'd feel when rotating?

Thanks for indulging my curiosity.
 
I offloaded 3 110 lbs. totes once. Manifest listed 0 Heavy bags. That means they were each counted as 30 lbs. I'd say about 60% of the time, the manifest didn't match what I offloaded.
 
Everything is based on averages anyways.

That said, I've certainly rotated before with the correct stab trim set (per the w&b computer) only to have to push or pull pretty hard to keep the plane doing what it should be.
 
Delta W&B system is awesome, but you still have people that don't know how to insert the baggage info into the right bin. I will ask the captain if he notice anything different, he will often say, "yeah required more back pressure to keep it flying." We been getting Delta POS MD-90's a lot and our main runway is under construction, so we lose about 2,000 feet and loading those bags means a lot.
 
Think about it. The airlines use (IIRC) 180 lbs as the average weight of a passenger+carry-ons. And then if they are too heavy, they might move some bags to the overheads to magically make them not count in the W&B. Airliner W&B is at best a calculated guess and at worst a farce. There's a reason the performance charts have cushioning on them.
 
Roger said:
Think about it. The airlines use (IIRC) 180 lbs as the average weight of a passenger+carry-ons. And then if they are too heavy, they might move some bags to the overheads to magically make them not count in the W&B. Airliner W&B is at best a calculated guess and at worst a farce. There's a reason the performance charts have cushioning on them.
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Yep. Though I suspect that the weight of the airplanes being operated help out a little. Let's say that Airline X's W&B procedure is good to 5% of total weight.

If you weight in at 60000LBS at MTOW 5% of that gives you a 3000lb margin of error to play with, that should cover the extra 50lbs per passenger out to 60 pax.

Balance (which is more critical in a lot of ways) is a bit trickier. I'd be very concerned about the possibility of running out of trim with a super tail heavy airplane that was loaded, "in CG," by the rampies, and with People of Walmart riding the aft cabin.

However, the airlines certainly have a procedure that figures it out to some arbitrary margin of safety.
 
Just another reason that I'm glad that most passengers don't know the kind of guys we have working ground crew in some places, I guess.

Thanks for indulging my curiosity.
 
Just another reason that I'm glad that most passengers don't know the kind of guys we have working ground crew in some places, I guess.

Thanks for indulging my curiosity.
 
There was a crew that didn't load over half the bags into a CRJ-700, but but the number that the computer said for the bag count. The plane managed to rotate and not turn into a big crater. ( But I assume it took a hefty pull to get the thing into the air). When you are missing ~2000lbs of weight that you think is in the ass end of the airplane I bet things could get dicey.
 
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