yep, you got to the point rfields5421, and it does land correctly when using flaps 25 and higher speed, same is almost the case with 777; but what is the reason behind such behavior? is there 'hunting' phenomenon coming into picture due to more than required sensitivity of autothrottle as well as pitch adjustment by autopilot? because i have noticed this unstable throttling when a heavy is too light with more than required flaps.and another thing comes up: why all these problems completely absent in 737?? lands great at mtow with flaps 40 at 140kias. really curious to knowregards

The difference in weight of 300,000 lbs and 30,000 lbs in the overweight factor of the B744 vs the B734 is the reason the bigger aircraft has such trouble.It's all weight and trying to fly too slow too heavy.The autopilot instruments and control tolerances are basically the same in the B744 and the B734.The B734 is also having issues - but they are very small compared to the issues of the bigger aircraft. FS does simulate the momentum factor which heavier aircraft would exadurates the movements and hunting.Autothrottle is a mixed blessing. It's useful for FS, but like the real world, often a hinderance on final approach because the changes can be too large, too abrupt.Have you ever heard the phrase "getting behind the aircraft" ?That is when you are reacting to what the aircraft is doing, not anticipating the aircraft and controlling what it will do. That's real good way to crash in FS, and kill yourself in the real world. You have to stay ahead of the plane - nothing it does should be a surprise.An autothrottle is always reacting, not anticipating.i.e. A real pilot, and a good FS pilot, increases the throttle slightly before/as he lowers another notch of flaps to anticipate the increased drag and keep the speed steady.An autothrottle reacts to the increased drag and add extra power to try and catch back up.I find it best to let the autothrottle establish itself on descent as after the aircraft is stabilized low, but turn it off for the final 5-10 miles.Also, the autothrottle is extremely fuel inefficient in FS.If you are trying to practice and learn approaches and landings - get the fuel weight off the aircraft - down to 25% or so.PS - we are talking FS2004 default aircraft. Addons may exhibit different behaviors due to the way their flight dynamics have been customized.

>Ever see the landing test video of the DC-9 where the back end>of the aircraft was broken off?yes, it was a mistake. the md80 was dialed in at 1500fpm descent when it "crashed" onto the runway was what i had heard. i think it was supposed to be 500fpm (which is still very hard).it was evidently an FAA pilot who screwed the pooch on the md80 tail breaking off.http://yarchive.net/air/airliners/md80_cert_crashes.htmlhttp://www.youtube.com/watch?v=E-flw0WfjRk

>most landings touch down at very little feet per minute>vertical rate. if it can stand the stress of a MTOW takeoff in>a crosswind (or by that measure a MTOW abort right at V1), by>golly it can stand a smooth MTOW landing. its not comparing a>CRJ to a 777, but rather design limits governed by the>applicable FAR's.Regardless of the vertical rate at touchdown an aircraft the size of the 777 or 744 requires an overweight landing check before further flight if landed above MLW. Even on the 727-200, we have to do an overweight landing check if landed above MLW. It's a two part multiple item inspection. Part 1 looks for obvious visual damage on specific items. If nothing is found then it's ok to fly. If problems are found in Part 1 then Part 2 of the inspection is carried out which is more in depth.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpgwww.SSTSIM.com

>Regardless of the vertical rate at touchdown an aircraft the>size of the 777 or 744 requires an overweight landing check>before further flight if landed above MLW. Even on the>727-200, we have to do an overweight landing check if landed>above MLW. It's a two part multiple item inspection. Part 1>looks for obvious visual damage on specific items. If nothing>is found then it's ok to fly. If problems are found in Part 1>then Part 2 of the inspection is carried out which is more in>depth.exactly a simple check. not a write off of the airplane. the airplane CAN land above MLW in an emergency.

>exactly a simple check. not a write off of the airplane. the>airplane CAN land above MLW in an emergency.Not exactly a simple check. They can take anywhere from 8 to 16 hours and depending on the findings, several days. Aircraft have been written off in over MLW landings that initially appeared normal. Unless the emergency is dire, it's best to dump fuel if the aircraft is equipped or burn off the fuel to get below MLW before landing.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.sstsim.com/images/team/JR.jpgwww.SSTSIM.com

didnt hear about 'getting behind the aircraft' but surely did come to know this problem myself when flying in fltsim with autopilot and manually. i also observed the throttle hunting when the a380 had its ist touchdn at my local airport; obviously because it wasnt fully loaded. i could easily hear the engine rpm varying continously up and down, i have captured and uploaded the shortfinal-touchdn vid on google.but i still am not able to get why extending flaps aggregates the problem? any ideas??

but i still am not able to get why extending flaps aggregates the problem?When you extend the flaps it's just like slamming on a huge speed brake.We extend flaps to allow the aircraft to fly slower speeds by having more lift - but it's a lot of extra drag.Because the autothrottle is trying to maintain the same speed but a new brake is deployed - it has to surge - and at the final flap settings - it may well go to full throttle.