Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Centre Of Gravity If Passengers Move All At Once  
User currently offlineA520 From Switzerland, joined Jun 2006, 122 posts, RR: 0
Posted (7 years 11 months 1 week 19 hours ago) and read 5399 times:

Is there an issue on the centre of gravity of large aircrafts if passengers all (or a majority of them) move to the front or back of the aircraft (triggered may be by a sudden threat at one end - hijacker with a gun?), or to one side? Could the CG move too fast too far and render the aircraft out of control?

Thanks to all

50 replies: All unread, showing first 25:
 
User currently offlineCURLYHEADBOY From Italy, joined Feb 2005, 940 posts, RR: 2
Reply 1, posted (7 years 11 months 1 week 18 hours ago) and read 5386 times:

I remember some soccer fans, high on drugs and alchool, started to do this exact thing on a charter flight, time ago. Pilots made an emergency landing and they were (no surprise) arrested. I'll try to find the article, if it's still on the web...


If God had wanted men to fly he would have given them more money...
User currently offlineRedcordes From United States of America, joined Jan 2006, 245 posts, RR: 0
Reply 2, posted (7 years 11 months 1 week 18 hours ago) and read 5381 times:

I've often wondered whether moving the passengers to the back of the doomed Alaska Air DC-9 with the stabilizer stuck in a somewhat nose-down position would have helped make the aircraft more flyable?


"The only source of knowledge is experience." A. Einstein "Science w/o religion is lame. Religion w/o science is blind."
User currently offlineSlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 3, posted (7 years 11 months 1 week 18 hours ago) and read 5381 times:

Perhaps.

I can tell you for absolute certain that it can be a problem in a Helio Courier with a 200 pound crate and a 200 pound "kicker" both moving to the aft end of the cabin during takeoff.

Quoting A520 (Thread starter):
or to one side?

Absolutely not. They cannot move far enough laterally to be felt, even when hand-flying.



Happiness is not seeing another trite Ste. Maarten photo all week long.
User currently offlineCURLYHEADBOY From Italy, joined Feb 2005, 940 posts, RR: 2
Reply 4, posted (7 years 11 months 1 week 18 hours ago) and read 5370 times:

Found the article, they were Serbian fans on a JAT 737, they made a mess of the plane (ripped off furnishings, oxygen masks, life vests), assaulted cabin crew, tried to get into the cockpit, tried to destabilize the aircraft by moving around all at once... it happened on Aug 2004.
Must have been a nightmare flight!

I post the link, only in Italian, sorry.

http://ilmattino.caltanet.it/hermes/20040831/MILANO/SPORT/FEFE.htm



If God had wanted men to fly he would have given them more money...
User currently offlineSlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 5, posted (7 years 11 months 1 week 18 hours ago) and read 5369 times:

As a followup to the above reply let's put some reasonable numbers to the question.

A change in CG is equal to the weight to be shifted times the distance it is moved, divided by the total gross weight of the airplane.

So let's take an example of a plane that weighs 160 thousand pounds at this moment. Let's say thirty passengers at an average weight of 180 pounds rush forward or aft an average distance of 360 inches (thirty feet)

Then: 360 X 5400 = 1,944,000 inch-pounds.
Divided by the 160,000 lb gross weight means the center of gravity shifts
12.15 inches.

Is that enough to cause a problem?
Perhaps.



Happiness is not seeing another trite Ste. Maarten photo all week long.
User currently offline2H4 From United States of America, joined Oct 2004, 8955 posts, RR: 60
Reply 6, posted (7 years 11 months 1 week 17 hours ago) and read 5341 times:
AIRLINERS.NET CREW
DATABASE EDITOR




Quoting SlamClick (Reply 3):
Quoting A520 (Thread starter):
or to one side?

Absolutely not. They cannot move far enough laterally to be felt, even when hand-flying.

That surprises me, as helicopters (if I'm not mistaken) are susceptible to their CG being out of lateral limits. I realize I'm comparing helicopters to transport-category jets, but the percentage of weight moved and the distance required for it to have an effect seem to be proportional between the two.

That said, Capt. Slam knows a heck of a lot more about the topic than I do....  Smile

Quoting CURLYHEADBOY (Reply 4):
they made a mess of the plane (ripped off furnishings, oxygen masks, life vests), assaulted cabin crew, tried to get into the cockpit, tried to destabilize the aircraft by moving around all at once...

Right....that's when you don the O2 masks and dial the PAX pressurization waaaaay down....  Wink




2H4





Intentionally Left Blank
User currently offlineAirWillie6475 From United States of America, joined Jan 2005, 2448 posts, RR: 1
Reply 7, posted (7 years 11 months 1 week 17 hours ago) and read 5330 times:

It depends on the weight of the aircraft and that aircraft's CG numbers so a blanket answer for your scenario is not possible. Find the formula for calculating CG and your aircraft cg limitation numbers and see for yourself.

User currently offlineSlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 8, posted (7 years 11 months 1 week 16 hours ago) and read 5303 times:

Quoting 2H4 (Reply 6):
That surprises me, as helicopters (if I'm not mistaken) are susceptible to their CG being out of lateral limits.

You are quite correct. The differences between helicopters and airplanes is, in my opinion, most marked when talking about flight control and CG management. Many newer helicopters are able to effect an increase in longitudinal CG range though use of horizontal stabilizers, sync elevators and so forth. To my knowledge no such devices have ever been deployed for lateral stability. In general, helicopters have very small CG envelopes for their gross weight. An exception is the tandem rotor CH-47 for obvious reasons.

The conventional helicopter hangs beneath a rotor disk. The CG must fall somewhere almost directly beneath the rotor mast and limitations on CG placement have to do with such things as main rotor yoke - mast bumping, or range of motion of the swashplate. In other words keeping the airframe hanging in a stable condition beneath the rotor disk.

A number of helicopters (Bell 212 if I'm not mistaken) require lateral CG as part of the weight & balance. Earlier, simpler aircraft had the requirement but achieved it with seating rules: Solo from left (or center) seat only, and so on.

When thinking about CG shifts as well as control authority "inch-pounds" is the unit of reference. 130 pounds held out 7 inches equals 910 inch-pounds for example. So on a typical jet airliner who knows how many pounds of UP or DOWN force can be generated by the ailerons multiplied by the five or six hundred inches they are from the CG and you can see why fixed wing have so much control authority.

The Airline Transport Pilot license for helicopters (ATH) has sample problems relating to lateral CG.



Happiness is not seeing another trite Ste. Maarten photo all week long.
User currently offlineCURLYHEADBOY From Italy, joined Feb 2005, 940 posts, RR: 2
Reply 9, posted (7 years 11 months 1 week 15 hours ago) and read 5269 times:

Quoting 2H4 (Reply 6):
Right....that's when you don the O2 masks and dial the PAX pressurization waaaaay down....

LOL! That would have done the trick, you raise cabin altitude and put the bad guys to sleep! Big grin , good one 2H4, i had a good laugh out of it!



If God had wanted men to fly he would have given them more money...
User currently offlineSlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 10, posted (7 years 11 months 1 week 15 hours ago) and read 5259 times:

Quoting 2H4 (Reply 6):
Right....that's when you don the O2 masks and dial the PAX pressurization waaaaay down....

I kind of favor just running cabin altitude up around ten to eleven thousand, not enough to cause any real injury, then crank the cabin temperature up to the "stuffy" setting. It puts everyone to sleep but not so dramatically that you get letters.

Actually I had a friend who did something like this once. He was flying for a military VIP flight detachment and through a schedule conflict wound up with two parties competing for his seats. One was a well-known entertainer and her other 'talent' and the other was Vice President of an Asian nation and his entourage. He could not transport all of either party and both thought it beneath them to ride with the other and all were in a nasty mood. So he took the steps as above and everyone went to sleep. Happy flight.



Happiness is not seeing another trite Ste. Maarten photo all week long.
User currently offlineMD-90 From United States of America, joined Jan 2000, 8502 posts, RR: 12
Reply 11, posted (7 years 11 months 1 week 10 hours ago) and read 5146 times:

I remember a pilot on the forum authoritatively stating that it was impossible for the passengers on a 747 to move around enough to get it out of c.g.

User currently offlineIlikeyyc From United States of America, joined Dec 2003, 1373 posts, RR: 20
Reply 12, posted (7 years 11 months 1 week 10 hours ago) and read 5141 times:

Quoting SlamClick (Reply 5):

Good math, Slam. Care to try it with 10,000 pidgeons in the equation?  Silly  Big grin  Wink



Fighting Absurdity with Absurdity!
User currently offlineStarlionblue From Greenland, joined Feb 2004, 16991 posts, RR: 67
Reply 13, posted (7 years 11 months 1 week 8 hours ago) and read 5095 times:

Quoting MD-90 (Reply 11):
I remember a pilot on the forum authoritatively stating that it was impossible for the passengers on a 747 to move around enough to get it out of c.g.

Using Captain Click's math:

400 pax x 75 kg = 30 000 kg.
All pax more 35 metres = 1 050 000 meter kilos.
747 with some fuel burned off = 350 000 - 30 000 of pax = 320 000 kg.

1 050 000 / 320 000 = 3.28 meters CG shift. I don't know exactly, but I would guess that's well within the CG limits, never mind the control authority of the aircraft.


A more interesting question is how fast you would have to move a hypothetical 30 ton weight back and forth in the fuse 35 metres to overcome the stabilizer trim system and make the aircraft pogo.



"There are no stupid questions, but there are a lot of inquisitive idiots."
User currently offline2H4 From United States of America, joined Oct 2004, 8955 posts, RR: 60
Reply 14, posted (7 years 11 months 1 week 8 hours ago) and read 5075 times:
AIRLINERS.NET CREW
DATABASE EDITOR




Quoting Starlionblue (Reply 13):
A more interesting question is how fast you would have to move a hypothetical 30 ton weight back and forth in the fuse 35 metres to overcome the stabilizer trim system and make the aircraft pogo.



I can see the headlines now.....






ONLINE AVIATION INTEREST GROUP STEALS AIRLINER, WREAKS HAVOC IN SKIES. CONTROL BARELY REGAINED, FEW INJURED. ALCOHOL A POSSIBLE FACTOR.





Lulea, Sweden (AP) - Investigators are working around the clock to determine the series of events that caused a stolen Boeing 747 to depart controlled flight and nearly crash into the Baltic Sea on Thursday evening.

Witnesses reported seeing an unruly crowd of "airplane nerds" gain access to Arlanda airport in Stockholm, and proceed to steal a parked Boeing 747 airliner.

"The crowd consisted of about two dozen individuals, each wearing pocket protectors and carrying elaborate calculators", reported taxi driver Fredrik Gustafsson. "They were whooping and hollering, and appeared to be involved in a heated discussion. At least one man was injured before even reaching the aircraft, when a fight broke out and large slide rules were used", Gustafsson reported.

The unruly mob appeared to be led by a very calm and wise man, known only as "Captain Slam". It is believed he started the aircraft and initiated the takeoff before things got out of control.

Details are scarce, but reports indicate unauthorized experiments took place in flight, leading to structural damage and a departure from controlled flight.

Control was finally regained when an unnamed quick-thinking maintenance technician leapt into the flight deck, quickly re-rigged the flight controls, and re-trimmed the aircraft.

"There are still so many questions", the technician explained. "How do you damage an aircraft in such a way." "What did they do to send the aircraft so violently out of control." "Were they not belted in down there." "I still do not know how they did it."

After control was regained, the aircraft was escorted back to Stockholm, where the rowdy group was detained and held for questioning. Sentencing is expected to take place next month.





2H4





Intentionally Left Blank
User currently offlineStarlionblue From Greenland, joined Feb 2004, 16991 posts, RR: 67
Reply 15, posted (7 years 11 months 1 week 7 hours ago) and read 5069 times:

 rotfl   rotfl   rotfl   rotfl 


"There are no stupid questions, but there are a lot of inquisitive idiots."
User currently offlineSlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 16, posted (7 years 11 months 1 week 7 hours ago) and read 5063 times:

Quoting Starlionblue (Reply 13):
Using Captain Click's math:

Never do math in front of an audience!

Quoting Starlionblue (Reply 13):
400 pax

I hope I never have a plane with that many terrorists OR heroes onboard!

Quoting Starlionblue (Reply 13):
x 75 kg

Must be Europeans - Americans weigh a lot more than that!

Quoting Starlionblue (Reply 13):
All pax more 35 metres

Okay now just a minute. I'm pretty sure that is more than half the aisle length on a 747. The running they do TOWARD the CG does not count. Also each person that runs forward offsets one who runs aft - unless the person running aft is me. (You'll recognize me by the parachute. I'm going for help.)

Quoting Starlionblue (Reply 13):
3.28 meters CG shift

It is okay because some ran forward, some ran aft, some ran in little circles. "When in danger, safety in doubt, run in circles, scream and shout!" So adding them algebraically, the net movement was less than the Slammer sliding his seat aft to take a nap - I mean scan the overhead panel.



Happiness is not seeing another trite Ste. Maarten photo all week long.
User currently offlineEssentialPowr From United States of America, joined Sep 2000, 1820 posts, RR: 2
Reply 17, posted (7 years 11 months 1 week 6 hours ago) and read 5032 times:

Mathematically, and movement of a mass in the cabin changes the location of the cg as has been stated. The most significant changes would be in terms of pitch. If many people ran forward or aft, and packed themselves tightly, a critical exceedance of the cg limts could occur.

User currently offlineTurkee From , joined Dec 1969, posts, RR:
Reply 18, posted (7 years 11 months 1 week 2 hours ago) and read 4992 times:

I've done a lot of weight and balance documentation for B717-200s, and while it isn't a "large" aircraft, it's certainly not small either.

The COG of the aircraft can actually move longitudinally quite a margin in flight, while still remaining in the area allowed for safe operations. For instance, the fuel burning up during flight will shift the COG of an aircraft, and is what the pilots will base their trim tab adjustments on prior to landing. As somebody else has mentioned, lateral movement of the COG isn't really an issue.

The take-off and landing COG limits are a lot smaller than the in-flight limits. Don't ask me why, I'm not a pilot (or a physicist), I just know they are  Wink

Now, when planning a load sheet for pax and dead weight, blocking off three or four rows at the front or rear (or both) of the aircraft really helps to balance out the COG. You can assess it half-way through the check-in stage, and see whether or not you're coming in nose-heavy or tail-heavy, and unblock seats or move baggage loads accordingly. As long as it is within limits at the flight close-out stage, no worries - the passengers can really move around wherever they want during flight and it won't have any effect on the handling of the aircraft - until it comes to landing. I have heard pilots ask passengers to return to their original take-off seats on a light-load aircraft, because that's what their original weight and balance planning was based on.

Probably a bit off-track there, but might be some useful information for readers.

Cheers.


User currently offlineStarlionblue From Greenland, joined Feb 2004, 16991 posts, RR: 67
Reply 19, posted (7 years 11 months 6 days 22 hours ago) and read 4949 times:

Quoting SlamClick (Reply 16):
Quoting Starlionblue (Reply 13):
All pax more 35 metres

Okay now just a minute. I'm pretty sure that is more than half the aisle length on a 747. The running they do TOWARD the CG does not count. Also each person that runs forward offsets one who runs aft - unless the person running aft is me. (You'll recognize me by the parachute. I'm going for help.)



Quoting SlamClick (Reply 16):
Quoting Starlionblue (Reply 13):
3.28 meters CG shift

It is okay because some ran forward, some ran aft, some ran in little circles. "When in danger, safety in doubt, run in circles, scream and shout!" So adding them algebraically, the net movement was less than the Slammer sliding his seat aft to take a nap - I mean scan the overhead panel.

I was making certain assumptions.  Wink The most important one is that ALL the 400 pax were moving in the same direction at the same time. Since this is highly unlikely anyway...

Quoting SlamClick (Reply 16):
Quoting Starlionblue (Reply 13):
x 75 kg

Must be Europeans - Americans weigh a lot more than that!

If they're all Baseball batters perhaps. I would hazard that a good mix of Americans would average less than 75kg with clothing. Don't forget that women weigh less on average. But if you were planning to pogo the plane with running pax, you would of course pick big people.



"There are no stupid questions, but there are a lot of inquisitive idiots."
User currently offlineDavid L From United Kingdom, joined May 1999, 9523 posts, RR: 42
Reply 20, posted (7 years 11 months 6 days 20 hours ago) and read 4922 times:

Quoting 2H4 (Reply 14):

It's only a matter of time.  biggrin 


User currently offlineVikkyvik From United States of America, joined Jul 2003, 9767 posts, RR: 27
Reply 21, posted (7 years 11 months 6 days 20 hours ago) and read 4910 times:
Support Airliners.net - become a First Class Member!

Quoting 2H4 (Reply 14):
when a fight broke out and large slide rules were used

Slide rule? What's a slide rule?

Signed,
Today's crop of engineering students

 Wink

Quoting David L (Reply 20):
It's only a matter of time.

Soooo......who's up for a meet at Arlanda.......



"Two and a Half Men" was filmed in front of a live ostrich.
User currently offlineSlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 22, posted (7 years 11 months 6 days 19 hours ago) and read 4885 times:

Quoting Turkee (Reply 18):
while it isn't a "large" aircraft, it's certainly not small either.

Kinda comes down to whether or not you'd want one parked on your toes.

Quoting Turkee (Reply 18):
The take-off and landing COG limits are a lot smaller than the in-flight limits. Don't ask me why

The actual limits are given in the shape of the CG envelope. On a typical jetliner it is a graph* where going up is increasing weight, left is forward CG and right is aft CG. The increment across the bottom or top could be inches aft of DATUM or aft of LEMAC, or percent of MAC. The irregularly shaped area within the graph is usually narrower - meaning a shorter allowable CG range - toward the maximum and minimum gross weights.

So at takeoff - the highest weight - it will be probably the narrowest of any point in the flight. As fuel burns off your weight drops down into a broader allowance. Usually the landing weights still fall into a pretty broad zone.

There is another issue. We offset undesired pitch tendencies like 'nose heavy' or 'tail heavy' with stabilizer trim, and we maneuver the plane on this axis with elevator. Both the elevator and the stab trim are more effective at higher speeds, with higher airloads. So these things are least effective at takeoff and landing.

Quoting Turkee (Reply 18):
and is what the pilots will base their trim tab adjustments on prior to landing.

I don't know what your paperwork looks like but it's been my experience that while we do pre-set stab trim for takeoff based on the weight & balance information, on landing we are flying the airplane and trimming according to feel, not paperwork. So on touchdown the trim is wherever the trim is. Lots of pilots as a personal technique may, in some types, begin trimming nose up when the mains touch down. They get a smoother nosewheel touchdown that way.

Quoting Turkee (Reply 18):
but might be some useful information for readers

Indeed, and thanks.

* I'll try to find an illustration and post it.



Happiness is not seeing another trite Ste. Maarten photo all week long.
User currently offlineSlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 23, posted (7 years 11 months 6 days 19 hours ago) and read 4880 times:

Center of Gravity envelope:



I haven't looked to see what type aircraft yet but this should give you the idea.

edit: Well I still can't see it very well. I'm talking about the graph on the left. The top horizontal line is this plane's max certificated takeoff weight, which looks to be about 210,000 lbs. The line at what looks like 145,500 lbs is the max zero-fuel weight. The greatest allowable CG range seems to be around 135,000 lbs and the range is roughly from 14% to 29% of MAC. Note also the max landing weight at 190,000 pounds. The CG range at that weight is only about 22% to 29% so this plane has some hefty restrictions on forward CG at high gross weights.

[Edited 2006-08-22 16:40:42]


Happiness is not seeing another trite Ste. Maarten photo all week long.
User currently offlineFredT From United Kingdom, joined Feb 2002, 2185 posts, RR: 26
Reply 24, posted (7 years 11 months 6 days 15 hours ago) and read 4807 times:

Quoting SlamClick (Reply 16):
The running they do TOWARD the CG does not count.

In fact they do, just as much as those running away from the CG. A kgm is a kgm, regardless of how it is generated.  Smile

Quoting Turkee (Reply 18):
The take-off and landing COG limits are a lot smaller than the in-flight limits. Don't ask me why, I'm not a pilot (or a physicist), I just know they are Wink

Prominent reasons include manoeuverability margins for rotation and (last but certainly not least!) landing loads on the aircraft structure, upon which CoG has a significant impact.

Quoting SlamClick (Reply 22):
The increment across the bottom or top could be inches aft of DATUM or aft of LEMAC, or percent of MAC.

Or index units... and someone will invariably end up mixing them up, regardless of what chart he is dealing with.  headache 

As for pax moving about, it can definitely make the CoG go out of whack in significant ways, at least in smaller aircraft. Severe constraints are at times put on take-off CoG envelopes when there are potential in-flight movements which can put the aircraft outside of the in-flight CoG limits if they take off at the take-off envelope CoG limits.

If you have a front row passenger standing in line for the aft lav while one flight crew member is in there, and then the F/A takes her trolley and pours a passenger in the last seat row a drink... then you have some weight travelling quite a distance. CoG envelopes are often narrower than you'd think.

If you lot are really interested, I can take a look at some of the heavy iron and see just what it would take to create a problem.

Rgds,
/Fred



I thought I was doing good trying to avoid those airport hotels... and look at me now.
25 SlamClick : I got ramp checked one night, flying with my boss, the DirOps. The FAA inspector looked at the weight and balance and said: "You are pretty near aft
26 Lowrider : When flying jumpers, having significant numbers leave the aircraft at the same time can make for interesting times as well.
27 Post contains images Starlionblue : I always wondered why one of our jump plane pilot would go into a spinning dive as soon as he dropped the last jumper. Personally, I think he missed
28 Zeke : On the Airbus its a QRH item to move pax to about to help with CG location in the event of abnormal gear extension.
29 Greasespot : Funny story.....When I was 16 flying home frome Germany the captain said "If you look out the left window you can see Glasgow...As people crossed over
30 Post contains images Turkee : I didn't find that funny. Thanks SlamClick and FredT for your comments
31 HAWK21M : Amazing people actually reacted. Pls elaborate. regds MEL
32 ImperialEagle : Back in the summer of '64 UA lost a 700 series Viscount near Newport, Tennessee. The aircraft had been observed flying in an erratic manner at a very
33 Post contains images Jetlagged : Of course, if you replaced the cabin floor with a conveyor belt ..... I remember a TAA 727 pilot joking that flying into Sydney over Bondi Beach they
34 SlamClick : Which is why in Saint Maarten there is a rule at Maho beach that the scenery must distribute themselves equally on both sides of the extended centerl
35 Tom12 : You would think that this would be possible. Maybe not in the likes of a 777 bu somehing little like a Fokker 50? .... would be pretty scary if it was
36 Jamesbuk : Thats slightly true, our flying club took a flight over to LE torquet (?) and on the way there i was in a piper seneca, as we were landing the owner
37 ZOTAN : The smaller the plane, the more effect it would have. I was departing MYF once, and my seat slid back right after rotation because it wasn't locked in
38 Jamesbuk : Hence in the Checklist "Make sure your seat is fully secure and locked before takeoff" kind of like if you normally have a skinny flight inst then ha
39 Post contains images TimePilot : To the original poster, A520. Funny that you should be from Swizerland, as this reminds me of something that happened in Zurich many years back. There
40 DernierVirage : My comment below is a little bit away from the original post, but it may be useful as part of the various discussions above... A few years ago I was o
41 SlamClick : Yes - if the cabin is configured as I would expect First, Business, Coach from front to rear. Sometimes, with very light loads in the 1st and/or busi
42 DernierVirage : Thank you for this information; in fact, the incident I mentioned is the only time this has ever happened to me in a similar situation It in fact was
43 BHMBAGLOCK : I was on a DC-3 one time where about 40 jumpers all moved to one side(left as I recall) together as an experiment. It did cause a slight(very) change
44 Starlionblue : All the planes I jumped out of didn't have more than two seats. I sat on the floor of Islanders and one engine Cessnas, often with a leg dangling out
45 BHMBAGLOCK : Trust me on this, even if packed in tight, it's more than a bump if you crash and you would be better off with seatbelts. I say this as somebody who
46 Post contains images DEVILFISH : Looking at the 744's seatmap, how difficult would it be to tightly pack all 400 passengers aft, or forward and up the upper deck to attain the 35 met
47 Starlionblue : You make a compelling argument. It would not really be that hard. AS I recall, El Al flew almost 1000 people on a 747 evacuation flight. Running up a
48 Post contains images DEVILFISH : We're only talking about 400 pax. Assuming the a/c is perfectly balanced and the CG is exactly at midpoint of the 744's 70.7 meter length from noseti
49 JetMech : Within certain limits, the longitudinal trim of an aircraft is self correcting. Imagine a 747 trimmed to be longitudinally neutral at some set of cons
50 Post contains images Petertenthije : Well, give someone from the UK a million dollars and it won't be long before they are pissed either.
Top Of Page
Forum Index

Reply To This Topic Centre Of Gravity If Passengers Move All At Once
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
Centre Of Gravity posted Sun Feb 24 2002 09:54:57 by Mb339
Meaning Of "Stand-By For All Call" posted Sat Sep 4 2004 16:00:33 by SafetyDude
Center Of Gravity VS. B1 Bomber posted Thu Mar 18 2004 13:31:01 by Techrep
Center Of Gravity posted Fri Jan 4 2002 00:04:27 by Notar520AC
Why The Little Hole At The Bottom Of The Window? posted Tue Oct 17 2006 03:19:07 by Gh123
Weight Of A340's Centre Bogey? posted Mon Jul 31 2006 19:56:41 by Zvezda
What Can Pilots Do If All Engines Fail? posted Sun Apr 30 2006 13:33:25 by United Airline
Seats At Back Of 737 And Its Speed posted Thu Apr 27 2006 16:45:42 by DeltaDC9
Does Any AorB Start All Engines At The Same Time? posted Thu Sep 8 2005 02:05:07 by MD-90
Hydraulic System...if All Engines Stops posted Mon Aug 29 2005 18:19:22 by D5DBY

Sponsor Message:
Printer friendly format