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Weight-and-balance is determining that an aircraft is loaded within the limits of it's weight carrying capability and that the center of gravity is within the operational envelopes of the aircraft.

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Is it okay to take off with weight more than the POH max gross weight?

I wonder if I could take off with weight more than the gross weight stated in the POH of my aircraft as long as I take off with a higher speed? I think I have done it once by mistake.
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2answers
228 views

Do airlines use a software to calculate center of gravity? [duplicate]

How do airlines calculate center of gravity? I have read in several airlines websites that they optimize the center of gravity position, to improve aerodynamic performance and reduce fuel consumption. ...
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1answer
191 views

What is the maximum number of cabin crew members on an A320 load sheet?

What is the maximum allowable number of cabin crew members to be mentioned on the load sheet for A320, with respect to weight and balance? And does the number of deadheading crew members add to this ...
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0answers
145 views

Why is a weight and balance graph lozenge-shaped?

(fireair.co.uk) Why is a weight and balance graph lozenge-shaped? I have tried to find the answer but it seems to be really hard to find. Why is it not a square?
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2answers
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Is it possible to install a bike rack on a Cessna 172?

I stumbled upon a nice photo manipulation on aviationhumor.net. Source My question is short and concise: Is it practically possible to do that? Is it okay in terms of aerodynamics, weight, CG? ...
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2answers
1k views

How do engineers make sure UAV don't land on their front propeller?

Take, for instance, the following UAV: and suppose you have a payload with a very big volume that fits exactly in the fuselage (and there is no more space), but is extremely light. Thus, the heaviest ...
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1answer
6k views

What is RTOW and how is it different from MTOW?

Please explain what is RTOW, and what is the difference between RTOW and MTOW. Is there a link between the RTOW and the Weight and Balance Manual?
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3answers
361 views

Does cargo balance affect fuel efficiency in commercial aviation?

Positioning cargo such that the center of gravity of the plane is within a certain range is essential, but is there any advantage to having the center of gravity closer to some ideal point within the ...
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1answer
184 views

Do modern aircraft have sensors to determine weight of the aircraft? [duplicate]

Do ALL modern aircraft, particulary airliners and private jets, have weight sensors on all landing gear to determine take off and landing weight in real time so as to determine take off speed and ...
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1answer
100 views

Is more cargo loaded if there is less passengers than expected?

When pre-flight weigh in is done, if the plane weighs less than expected because people don't turn up, is more cargo added? Conversely - if the plane is over the estimated weight - does cargo get ...
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0answers
190 views

What calculations are needed for counter-weight balancing on a propeller?

I am designing a small-scale propeller and i have managed to design on optimized geometry for the blade. However the blade pitch angle adjusts according to different flow speeds so i need to mount ...
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2answers
512 views

What is the largest aircraft (by max takeoff weight) in which all engines are in the tail?

The largest one I'm aware of is the Il-62, with a whopping 4 turbofans at its tail. Max takeoff weight is 165 tons. I actually don't care how many engines there are, as long as all are at the tail. I ...
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4answers
608 views

What performance issues/symptoms can a pilot expect while taking off above MTOW?

Lately I've been flying a Cessna 162 Skycatcher, primary as a cheap way to build time towards the Instrument Cross Country requirement and my glider club's hours requirement to tow gliders. One issue ...
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7answers
7k views

Can an airline reject a passenger for being overweight?

I have a Cessna 172S and despite having 4 seats in the cabin, I cannot take 3 more passengers besides myself as the pilot with a full tank of fuel due to safety in weight balance issues. As the pilot,...
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3answers
428 views

Do the pilots have to recalculate the balance when 6 passengers show up last minute in a 737? [duplicate]

Few years ago me and my mates forgot the checkin time and were late for flight. We were late for check-in counter closure (30 minutes before flight if i'm not wrong) but the staff allowed us to go on. ...
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2answers
335 views

Can the center of gravity ever fall outside the mean aerodynamic chord?

Can the aircraft center of gravity be outside the mean aerodynamic chord (i.e. %MAC being negative or more than 100%), at least theoretically? I'm not an expert in aviation. All I've heard is the ...
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1answer
168 views

Is it permitted to load a full cargo container onto an aircraft without a roller track loading/locking system?

Aircraft with roller track cargo loading systems transport containers/pallets in the cargo compartments. When an aircraft doesn't consist of a certain system but just a flat floor (so for example a ...
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3answers
1k views

Do you have to update weight and balance charts after installing new avionics?

The POH always has weight and balance charts. Let's say you install some new avionics, hence changing the weight of the aircraft. Do you need to update the POH binder with new weight & balance ...
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2answers
415 views

What is the correct answer to this Mass and Balance calculation?

I was practising some mass and balance questions and I found that my answer is a little bit too far from the listed answers. Can anyone help me to see if I did something wrong? The question was: ...
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2answers
582 views

In a fighter jet, what is the average weight of the ejection system?

In the old days, pilots had only a parachute pack. (In the really old days they might not even have that.) They had to open the canopy manually and jump out. Today, fighter jets have zero-zero ...
6
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1answer
876 views

How is fuel removed from a light aircraft if required for weight and balance?

With small, light aircraft, weight is always a consideration. Say you had a four-place single engine aircraft that you wanted to take yourself and three of your (non-FAA-standard weight) friends, but ...
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3answers
300 views

What is a good spin aircraft for someone that is heavy?

I've been trying to get a spin endorsement for my CFI, but I've been having a problem trying to find an airplane that I can do it in. I'm 280 built like a linebacker. I'm not that "fat" just heavy....
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1answer
144 views

How many axes are used in weight and balance calculations?

When doing weight and balance calculations on fixed wing aircraft is the transverse axis (wingtip to wingtip direction) used? Or is only longitudinal axis considered?
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1answer
3k views

Where is the best center of gravity?

I'm designing a plane, and I have a question. What is the best place for the center of gravity, relative to the center of lift? I've heard that it's best put just behind the center of lift, but I ...
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2answers
896 views

Do you need to put your wings at the center of gravity when building an airplane?

I have been wondering about this for quite a while and can't find an answer.
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1answer
273 views

How do I modify the aircraft weight and balance after a battery replacement?

I am looking to replace my Gill battery with a Concord. The regulations appear to allow me to do this as an owner. However, the Concord battery weighs 2 lbs more. I cant find it in the regs if I ...
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3answers
1k views

How can I find the CG of a model aircraft based on its dimensions? [closed]

Given the dimensions and gross weight of an RC model aircraft, how can I find the center of gravity? Can I calculate it, or perhaps there's some way to approximate it?
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1answer
510 views

Why is the top left corner cut off on the cg location envelope for small airplanes?

Why does the PA-28 C.G. envelope have the top left corner cut off rather than allowing higher weights at a forward C.G. like it does at the aft C.G.? (source)
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2answers
2k views

What would happen if a plane lost half of its weight instantly?

During the Second World War the RAF had a 10,000 kg bomb, the "Grand Slam", which was dropped from a Lancaster bomber. I assume that when this was dropped the plane would lurch upwards. Is there any ...
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2answers
318 views

Would an accurate weight of a loaded aircraft be helpful?

If a commercial aircraft's actual weight at takeoff is accurately known (instead of being estimated), can this help with use of thrust, optimal altitude, etc and therefore fuel savings, emissions etc.?...
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2answers
275 views

How does a vertically higher center of gravity affect handling?

Much of the discussion of the center of gravity of the aircraft is focused on the longitudinal axis, i.e. front and back. How does the vertical position of the CG affects the handling characteristics? ...
3
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1answer
185 views

Are there pilot weight limits for the Rutan Vari Eze?

In this question on the Rutan Vari Eze it is said one of the reasons it parks nose down (gear up) is to bring the Cg forward for stability (so it doesn't tip over) when there is no pilot in the ...
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3answers
994 views

Which aircraft require that the vertical position of the centre of gravity is checked?

We normally check the aircraft CG along the longitudinal axis and the lateral axis (sometimes referred to as the transverse axis) to ensure it is within limits. Until recently I was unaware of any ...
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4answers
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What is the weight that is used to balance an aircraft called?

I remember I was reading about balancing an airplane a few days ago, and i came across a type of weight that is added to balance the airplane. But, I do not remember what it was called. Also could ...
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0answers
74 views

How is lateral CG managed in aircraft with uneven seating? [duplicate]

On many smaller jets seating is unbalanced with 1 seat on one side and 2 on the other side of the aisle. Some examples are the Embraer ERJ-145: Source - SeatGuru Embraer ERJ-135: Source - SeatGuru ...
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3answers
24k views

What does %MAC mean?

A document said that the optimum CG position is from 13% MAC to 33% MAC. I'd like to know what that means, and what would this look like on an actual plane.
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1answer
975 views

Why should the centre of mass be ahead of the centre of pressure?

Why is the centre of mass located ahead of the centre of pressure? And what would happen if centre of mass would be too close or too far away from the centre of pressure?
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2answers
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What is the typical weight distribution ratio between nose gear and main gear?

On an airplane with tricycle gears, the main gear supports most of the weight and is therefore the strongest. The nose gear prevents the nose tipping down, since the center of gravity is forward of ...
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2answers
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How much does the landing gear compress on a fully loaded airliner on the ground?

When an empty airliner is loaded with passengers, cargo and fuel, the extra weight compresses the gear strut and it sinks. Jet bridges are designed with this in mind. How much height does it actually ...
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2answers
608 views

When one engine fails in a twin-turbojet aircraft, is there a weight imbalance?

In a turbojet aircraft with two engines, when one fails does the weight of the working engine increase due to the fuel flowing to it? If it does, how is the weight balanced on the failed engine side?
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2answers
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Will optimising the weight distribution of a commercial flight save fuel?

Since the centre of gravity must lay in a certain location, I'm wondering if it would save fuel if it lays exactly in the right spot? Let's assume that you have an A320 and weight distribution is ...
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8answers
9k views

What if all passengers pay to check in extra baggage?

Suppose a given flight is fully booked and everybody shows up. Not only have they all brought the allowed fully loaded carry-on & checked-in luggage weight but exceed the free-limits. They are all ...
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1answer
145 views

Would it help airlines, if they knew passenger weight before hand? [duplicate]

Its known that pilots and technicians calculate the weight of the plane once everything is loaded, then they can decide on how much fuelling etc. needs to be done. Would it help airlines, if they ...
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2answers
496 views

How much weight does removing a vacuum system really save?

For a small GA aircraft (e.g. Piper, Cessna, Mooney), does anyone have a before and after weight savings example from removing a vacuum system? E.g. calculated weight of component removal during W&...
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2answers
844 views

What weight and balance form should I use for my checkride?

I am studying for private pilot checkride and saw this form in an Oral Exam. Can you tell me where I can get this form online? If not, is there a better form for expiration and W&B data?
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2answers
5k views

How do airlines handle uncertainty in passenger weight for weight and balance calculations?

When commercial airlines calculate the mass and distribution of passenger load, in the cases where they do not weigh the passengers directly, they use standard weight measures which have been approved ...
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1answer
1k views

How does aircraft weight affect the glide performance? [duplicate]

Since the L/D ratio remains unaffected by the aircraft weight, will there be any effect to the gliding range?
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2answers
2k views

How can the Antonov AN 225 only have 2 nose wheels?

I was watching the video of the AN 225 unloading at Perth airport this weekend, and it suddenly occurred to me that there are about a zillion rear wheels on the aircraft, yet only 2 nose wheels? ...
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3answers
2k views

How reliable is the Airbus FAC calculated gross-weight?

I've noticed some variation between loadsheet weights and FAC (Flight Augmentation Computer) calculated weight. That's of course normal, since loadsheet is calculated with standard weights and FAC ...
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1answer
493 views

How do pilots of small planes know where to move people?

On a recent flight from Washington, DC to Toronto, the pilot gave very specific directions to rebalance the plane (a Dash-8 IIRC), something like "someone needs to move to seat 11E." How did he know ...