Ever move pax for W&B?

[skydiverdriver2]

Ever move them back after takeoff? I have seen this done, both on RJ's and larger aircraft. I asked the flight attendants about it, and they said the captain said it was okay. Well, we all know that burning fuel, especially in a swept wing jet, moves the CG foreward. However, the flight envelope takes this into account. You must be within balance for takeoff, enroute and landing. I hear the FAA is being very strict with this, especially after the Beech 1900 that went into the hangar in CLT. I would hate to see anyone get violated, especially for something as small as passengers not wanting to sit somewhere.

Just wanted to post a warning, take it or leave it. Have a happy Thanksgiving.

 

[WateryGrave]

From what I understand that Beech 1900 crash had more to do with faulty mx than it did W&B. That airplane could fly over weight and out of CG no problem (so I've heard.... =)). I highly doubt it had anything to do with the crash.

 

[skydiverdriver2]

Me too. However, that doesn't stop the FAA from using the crash to justify it's actions. Have you seen the movie, "We're Marshall?" That was a depiction of an actual crash, caused by weight and balance issues. Now we have to use actual weights with non-standard groups.

I'm sure aircraft fly every day overweight and out of balance. Perhaps it takes a specific situation to actually cause it to crash. But, that is why we have rules to follow. You don't have to crash to get a violation from the FAA.

 

[Charlie Brown]

I used to do it in the E145.

 

[CF34-3B1]

Happened all the time in the CRJ200, it was nose heavy to begin with, and the gate agents always asigned everyone seats as far FWD as they could. Then wondered why we had to move them.

 

[skydiverdriver2]

I used to do it in the E145.

What did you do?

 

[Huggyu2]

We did it on a lightly loaded 727, back when I was a flight engineer.

 

[skydiverdriver2]

We did it on a lightly loaded 727, back when I was a flight engineer.

Do you now see that you were doing something wrong?

 

[strega7]

Ever move them back after takeoff? I have seen this done, both on RJ's and larger aircraft. I asked the flight attendants about it, and they said the captain said it was okay. Well, we all know that burning fuel, especially in a swept wing jet, moves the CG foreward. However, the flight envelope takes this into account. You must be within balance for takeoff, enroute and landing. I hear the FAA is being very strict with this, especially after the Beech 1900 that went into the hangar in CLT. I would hate to see anyone get violated, especially for something as small as passengers not wanting to sit somewhere.

Just wanted to post a warning, take it or leave it. Have a happy Thanksgiving.

Never

 

[Dave's kid]

Ever move them back after takeoff? I have seen this done, both on RJ's and larger aircraft. I asked the flight attendants about it, and they said the captain said it was okay. Well, we all know that burning fuel, especially in a swept wing jet, moves the CG foreward.

If I remember correct, on the E-145 the CG moves aft as you fly because the fuel tanks were forward of the center of gravity.

Also, the 145 was almost always at or near the forward CG limit. So moving passengers to the back was never a problem, it was moving them forward that could become a problem.

 

[RadioClash]

Have you seen the movie, "We're Marshall?" That was a depiction of an actual crash, caused by weight and balance issues.

No but I have seen the movie "We Are Marshall", and that crash was caused by the DC-9 descending below MDA on approach, either due to pilot error or an instrumentation problem. NTSB-AAR-72-11, p. 36

Not sure what movie you are talking about.

 

[skydiverdriver2]

delete..

 

[skydiverdriver2]

Perhaps I was mistaken on the cause, thanks for correcting me. So, do you think it's okay to misload an aircraft, just because it didn't cause that crash?

 

[A350]

All:

Most W&B programs check the takeoff and ZFW CG....so if you deliberately move passengers aft or forward without re-running the W&B, how do you know you haven't exceeded the balance envelope?

A350

 

[crxpilot]

Well I think we've gotten a little sidetracked here. The question is, why is it NOT ok to move passengers back to their original seats after takeoff if you had to move them in the first place?

 

[siucavflight]

Perhaps I was mistaken on the cause, thanks for correcting me. So, do you think it's okay to misload an aircraft, just because it didn't cause that crash?

I have read through your post. I am not sure what you are getting at. Most of us now have our computers doing the weight and balance. We get a close out and it says how many people have to be in each section, if it is not right we move them.

 

[Charlie Brown]

What did you do?

I have done lots of things in that airplane

I misread the original question though, I moved pax before departure, but never after t/o due to W&B reasons. What the others said regarding the 145 is accurate and the reason we had to move people.

 

[gutshotdraw]

As a professional airline passenger (I don't get paid to fly, I get paid to airline back and forth to airplanes and sit around FBO's), I have been asked to change seats prior to departure in order to help put the airplane in CG. Dash-8 and BE-1900 trips spring to mind and at least 1 RJ trip although I can't recall which type. I've never been asked to move while in-flight however.

I guess I'm fortunate that I fly an aircraft that is virtually IMPOSSIBLE to load out of CG as long as max gross weight is respected (and that would require full tanks and more than half the pax seats filled).

 

[j41driver]

From what I understand that Beech 1900 crash had more to do with faulty mx than it did W&B. That airplane could fly over weight and out of CG no problem (so I've heard.... =)). I highly doubt it had anything to do with the crash.

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20030110X00049&key=1

Here's the NTSB report. Actually it had a very large part to do with the crash. This crash is why all airlines were required to revamp their W&B programs.

 

[WateryGrave]

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20030110X00049&key=1

Here's the NTSB report. Actually it had a very large part to do with the crash. This crash is why all airlines were required to revamp their W&B programs.

Thanks, I read the report too. Yes they were out of CG. However, if they were in CG the A/C still probably would have crashed due to the mechanical. Heck if they would have talked to each other on the taxi out the NTSB probably would have put some of the blame on them breaking sterile cockpit, even though we all would realize in had nothing to do with it.

 

[bubbers44]

No plane should ever be dispatched that requires moving pax after takeoff. Turbulence, etc could make it not safe to have pax unfasten seatbelts and wagging how many to move where would not set well with the FAA.

 

[yournextFO]

With the CRJ200, usually the landing CG is the limiting factor. On rare occasions the ZFW CG limits, most often seen with light fuel loads. Although theoretically possible, I have never seen a situation where the T/O CG was out of limits but yet the landing CG was still acceptable.

For most combinations of aircraft loading, fuel loading and burn, the CG moves forward as fuel is burned. So, theoretically, the passengers could sit in front for take-off as long as they moved to the back for landing, though the FAA probably wouldn't like that plan.

On a side note, I seem to recall the MD11 had a system whereby fuel was pumped into the aft (rear stab?) during cruise to take advantage of a more efficient rearward CG, and then pumped forward for landing.

 

[skydiverdriver2]

No plane should ever be dispatched that requires moving pax after takeoff. Turbulence, etc could make it not safe to have pax unfasten seatbelts and wagging how many to move where would not set well with the FAA.

You're joking, right? Perhaps you should read the original question again. I was warning people about the DANGER of moving pax after takoff, not the requirement for doing so.

I can't believe this got so far off track. Probably because you think it's funny. I really don't care. Now you know, and if you understood what I was saying, this may keep you out of trouble. Thanks to all the reasonable responders.

 

[Fedora]

On most of todays aircraft, the CG will move toward the inside of the W/B envelope as fuel is burned, so moving pax may be required to move your takeoff CG into legal limits for T/O, but once airborne it usually doesn't matter where the pax sit. Draw a line between your takeoff CG and your ZFW CG, and you will probably see that it cuts through the interior of the box as you burn fuel. I'm sure there may be different aircraft out there that are more CG sensitive, but for a modern passenger transport, once airborne, the CG will most likely be moving in a more stable direction. Aft CG's can adversly effect VMCa after engine loss (almost negligible in light aircraft - increasing with heavier machines), and on longer or stretched acft, increase chances for a tail strike.
Just my 2 cents. If you are really concerned, save a copy of the WB form and redo it with the pax in the original sections and a landing fuel figure. It should fall on the line described earlier.
Fly safe, all.