Hello all,Being a student pilot (C152) I learned that my airframe has a never exceed weight and that, if you go over it, then weight cannot be overcome by lift and you end up in the trees at the end of the runway. So, with this in mind, I have a question...In Microsoft FS2004, on many of the realistic payware add-ons (CaptainSim 707 & 727), you can easily exceed the MTOW by simply loading the aircraft down with full fuel & passangers. This does not even take the cargoholds into account (they are empty). So, do airlines actually operate aircraft beyond their MTOW, knowing that by the time they reach their destination the fuel will be gone and the aircraft will be within its acceptable limits?As a side note, As a child I once flew from Atlanta to Hawaii non-stop in a Delta L1011 and it was filled to capacity with passangers, and I expect fuel as well. Always figured we were running on vapors by the time we got to HON. Seems like it would have been overweight in KATL. Thanks for any info!Stephen

>Being a student pilot (C152) I learned that my airframe has a>never exceed weight and that, if you go over it, then weight>cannot be overcome by lift and you end up in the trees at the>end of the runway. I think you got it slightly wrong. Maximum takeoff weight does **NOT** mean that when you exceed it by 10 or even 100 lbs. airplane will never lift off the ground. Nevertheless this is the maximum takeoff weight the airplane was designed for. Given sea level, very cold and dry air (ideal takoff conditions) you can probably significantly exceed the MTOW and still fly pretty well.Airlines stay within the MTOW - I can bet you. They take all conditions under consideration - runway length, altitude, temperature before arriving at the maximum takeoff weight. By the way, I am not aware of "never exceed" weight. I think such a phrase does not exceed. But there is a "never exceed" speed (VNE).Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2, Omega 2.7.90 (4xAA 16xAF)

There are tradeoffs. There are certain routes out of here (Christchurch New Zealand) flown by 767-200s where the passenger cabin is mostly empty every time, because the hold is full and there isn't the weight capacity to fill the cabin and carry enough fuel.Some aircraft can fill the cabin, fill the hold, and carry enough fuel to fly halfway around the world. The 777, 747 and A340 all can, or close to it. Others have severe limitations at the edge of their range, like the 767.Most aircraft will take off well beyond MTOW. That doesn't mean they're safe if they do; stall recovery may be impaired, climb performance may be terrible, altitude ceiling may be unpredictably decreased, there may be no icing margin, or a number of other bad things may happen.

Hi Stephen,Many transport category aircraft have a heavier maximum takeoff weight than the maximum allowable landing weight. Landing weight is less than takeoff weight to prevent excessive structural loads being placed on the airframe, landing, gear, tires, etc.The amount of fuel, passengers, and cargo that a transport category aircraft can accomodate depends on several factors. There are weight limitations for accelerate/stop distance, all engines takeoff, and takeoff/cimb performance with a critical engine inoperative. All three are calculated and then the most restrictive weight is used. Some of the factors that limit the takeoff weight include temperature, field elevation, runway surface, runway slope, winds, flap setting, and so on. If the weight is too great, something has to be removed - passengers, cargo, or fuel.Several regulations address how much fuel the aircraft must carry, depending on the type of operation. The fuel on board will always be enough to fly to the intended destination (including any intermediate stops), then to an alternate destination if necessary, plus extra fuel for holding and possible delays.One other interesting weight limitation is the maximum zero-fuel weight. Turns out that the weight of the fuel in various tanks is used to balance structural loads placed on the aircraft by passengers and baggage. Aircraft often have to have a certain amount of fuel on board or a limited amount of cargo and passengers on the ground until the aircraft has been refueled.The main problem with flying over the allowable gross weight in any aircraft is overstressing the airframe. You may get the aircraft off the ground without ending up the trees, but you will put more stress on the airframe structure than it was designed to handle. Remember that the effects of overstressing an airframe are cumulative and often invisible. Something to think about when doing your weight and balance calculations. ;-)John