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Autoland Question

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I have a question regarding the autoland feature. Everything seems to be working OK, but I've been experiencing hard touchdowns between 380'fpm - 670'fpm. I have the green Autoland 3 light illuminated, all three autopilots engage at 1500'and capture the GS ok. I'm landing with appx 20% fuel, vr +5, flaps 30, spoilers armed at appx 140kts. I have attempted multiple attempts at KEWR, KPVD and KBGR with the same results. I am using FS Genesis Terrain Mesh, Ultimate Terrain and GE Pro. Any help would be greatly appreciated, I really love this aircraft....great job on it! :)Athlon FX604 GB PC3200ATI 1900XT 512 mb

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I believe this question was answered some time ago. I don't recall the exact details, however, I know that autolands are normally somewhat hard. The actual fpm at touchdown may be somewhat misleading on the vertical speed indicator, since I think in the last few feet, the aircraft is "forced" onto the runway, to prevent "floating". Since reverse thrust is not permitted at many airports now.The aircraft relies on braking to bring it to a stop,so it makes sense that the touchdown point is close to the landing end of the runway. The autoland on the Level D 767 is for some reason much gentler, but again, they are two different aircraft.Ron

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Ron, Thanks for the response and your explanation. I was just unsure how the 757 behaves on autoland as I also fly a 737 that seems to be a little gentler on touchdown, but like you said about the 767, it is a different aircraft. I'm just trying to figure out if I'm missing something or if this is normal. Thanks again for your response,Matt

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I was'nt sure which aircraft you were referring to, but I was referring to the 777. I guess touch down vertical speed can also be affected by airspeed and gross weight. I am not knowledgeable enough to know whether the LDS 767 autoland is or is not more authentic than the PSS 777, or 757. There maybe limitations within MSFS which lead to compromises in programming, however, that said, I still like both aircraft.Ron

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Matt,If you do a search, you will find a lot more on this in the forum - mainly because some felt that the 757 did not flare sufficiently or not atall{I believe that FS Passengers' pax were getting upset.}On my system, the 757 is flaring - just before touchdown the rod is usually reducing through 400 - 300 fpm. Also I think an automatic landing should be fairly firm to give more precision on touchdown point and stopping distance.However, this leads to the age-old arguement of which is the best landing - a greaser or a firm one? An argument which can go on all night - although my old QFI used to tell me that any landing was a good landing if you could walk away from it!John R

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Ron, John, Thanks for your responses, The 757 has been very consistent in capturing the glideslope for me and usually descends at approximately 700 fpm, then between 100-200 feet above ground level starts to flare some. I use the flight keeper program, it has gotten my touchdown anywhere from 360 fpm to 710 fpm, and usually states that I had a very hard landing. From the cockpit though it doesn't seem like a rather harsh landing. I know the developers put a lot of time and effort into producing this plane, and there are so many variables to take into account. I was thinking maybe the FS Genesis terrain mesh might have something to do with it. Possibly the airport elevation being different from the default? It's still one of my favorite aircraft to fly and thank the developers for all of their hard work on it. I agree with John, any landing you can walk away with is a good one!thanks again,Matt

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A fairly firm landing of passenger aircraft should be no more than 120 feet per minute. Anything larger would upset passengers and should be avoided for human transportation. The aircraft structure is not designed for such impact and would need to be inspected and overhauled at much higher than designed rate. At greater impact the nose wheel might approach unintended runway strike before pilot or autoland corrective action is applied. A smooth landing has a descent rate below 1 foot per second or 60 feet per minute.BTW aircraft carrier landings involve a descent rate four times greater, at about 500 feet per minute, depending on aircraft touch down speed (the variables are aircraft type and weight, ship speed and wind velocity), and deck impact point vertical speed.

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