September 12, 200322 yr Noticed on page 34 of the PMDG Flight Crew Training Manual that the pilots are supposed to initiate the flare at 15 feet. Is it possible for real world pilots to react fast enough at this height? Descending at, say, 750fpm, this would give them a window of 1.2 seconds to control the flare. The A/P, on the other hand, starts the flare process at 50'... with the throttle beginning to retard at about half that height.Is this a misprint? Basically, if you sneezed at 15 feet, the moment you had opened your eyes, you would already have hit the ground :-lolThanks.Cheers.Ian.
September 12, 200322 yr I don't know what they used but they are correct. I have Virgin SOPS which state main gear 15' AGL flare 2-3 degrees. [h4]Best Wishes,Randy J. Smithhttp://img.villagephotos.com/p/2003-8/196432/winglets_lg.jpg [h3] AMD XP 2200 |MUNCHKIN 512 DDR RAM |ECS[/b ][i] K7S5A MB[/i] |GF2 MX 32 MEG and still runs GOOD!|WIN XP PRO |MITSUBISHI DIAMOND PLUS 91 19"[/h3] Randy J Smith
September 12, 200322 yr Ian, at 15' I'd think you're well into ground-effect and your 750' rate of descent will automatically be slowing as the cushion builds. Just for fun, the next time you land the PMDG 737, set 30 flaps, knock out all the autos and kill the power by 50', flare at 15' and then do a C172-type landing holding off until she stalls. Just watch that baby float as the runway whooshes by!- Pete ("Isn't that a very unusual attitude, Captain? - No, it's just my normal viewpoint." :-)
September 12, 200322 yr that's where the pilot's "feeling" should take over...normally, the attitude you fly at 15ft AGL will not tolerate a 750fpm descent....as a glider pilot i can confirm this as this is really something i struggly with each landing. choosing the correct timing for flaring is really important and can be pretty late, the first time will never be good, but as you build experience you get to feel when to flare and from that time it all goes well...believe me!btw: on a 1.2 second window does not mean you have 1.2 second to start the whole flaring process, you will probably allreay make the movements prior to that 1.2 seconds meaning the movement will take place in those 1.2 seconds giving it adequate time... another thing: in a cessna you can start flaring on the last possible moment ,in a jet you cannot as it acts waaaayy more sluggish(sorry, not a native english speaker)
September 13, 200322 yr "Ian, at 15' I'd think you're well into ground-effect and your 750' rate of descent will automatically be slowing as the cushion builds."Thanks, Pete. I should have thought of that.... being a non-pilot I am forever experiencing "ground effect" :-)"...set 30 flaps, knock out all the autos and kill the power by 50', flare at 15' and then do a C172-type landing holding off until she stalls. Just watch that baby float as the runway whooshes by!"This may take a bit of practise... At the moment, the only whooshing sound I can hear is the air escaping from my tires.... :(http://members.ozemail.com.au/~b744er/737/HeavyLanding.jpgI think I forgot to compensate for the extra 10 feet built into PMDG's Rad Alt ;-)Cheeers!Ian.(P.S. Sorry, John T... Looks like I've bent your beautiful Qantas aircraft)
September 13, 200322 yr your english is fine!! Yep I had problems transitioning to a cessna because I would flare way too early and i would stall out way too high, i have gotten better and started to amke softer landings now, on a jet, it doesnt mean you start the movement at 15 feet, but yes ground effect will help. I know when I hear 50 I idle the throttles and then at around 20 i begin easing back, so yes at around fifteen feet the plane flares, and settles nicely, however that is my touch and might not necessarily work for you. Heres a tip: Set up a flight, that is stabliized on the approach and all the checks completed at 1 mile or half a mile out. If you want to work on your flare, keep the manual guidelines in mind but just experiment and see how you can make the landing to your liking. Like try the first one by the book--and then see what you need to change. NOTE---Do not ever pitch the nose down once you have flared, if you seem to float...decrease the amount of flare, also, i know it tends to seem to help, but never extend the speedbrakes with full flaps extended, I have heard from real-life pilots that it is very dangerous to do so. So, just set up a flight thats where you want to begin on the landing sequence and just practice your flare. Keep restarting the flight (CTRL+ ;) and just practice. Start with winds calm, then work up onto the more exciting crosswinds. I know it sounds basic, but sometimes the more basic stuff helps the best!! I know it did for me. And remember a JET is not a GA plane!!
September 14, 200322 yr I just tried out flaring at 15ft AGL today while doing a full ILS approach. I ended up slamming to the runway quite hard and had a bounce. :) Nothing broke but still a hard landing. So, either there's not enough ground effect in FS or then you really shouldn't count on numbers, but visual reference instead, like I've done before.
September 14, 200322 yr Well the passengers might not have liked it but really a hard landing is sometimes a more correct landing than wasting runway to put her down softly. Now I don't mean to bounce her ;). Once you pass the threshold key in on about 3/4 down the runway lenth, set idle thrust at flare height and pitch attitude to 2-3 degrees to slow the ROD to the runway. The best way is to try to get the engines at idle thrust upon touch down of main gear. I think some forget that you should be at a 3 degree profile on approach and must pitch 2-3 degrees MORE so you would be looking at 4-7 degrees in pitch attitude on flare. So a constant speed (VREF + any adjustments) and correct profile will give you a very good start for a correct landing.[h4]Best Wishes,Randy J. Smithhttp://img.villagephotos.com/p/2003-8/196432/winglets_lg.jpg [h3] AMD XP 2200 |MUNCHKIN 512 DDR RAM |ECS[/b ][i] K7S5A MB[/i] |GF2 MX 32 MEG and still runs GOOD!|WIN XP PRO |MITSUBISHI DIAMOND PLUS 91 19"[/h3] Randy J Smith
September 14, 200322 yr Yeah I've found it a lot better to flare the way you described it. :)Actually, I was flying with Sabena a few years back from Helsinki to Brussels. During landing, as we crossed the runway threshold at about 50 feet, the plane still continued at the same descent rate, and I already assumed we're gonna hit the pavement hard :) until just a few feet above the runway the captain (female) cut the throttles and rapidly flared the plane, and I really felt that flare! The landing was just about perfect, and I've never seen such a perfect "late" flare again.Btw, I assume Ian really made a bad landing... even the winglets of his plane are pointing down booing for him. ;)
September 14, 200322 yr >Btw, I assume Ian really made a bad landing... even the>winglets of his plane are pointing down booing for him. ;)LOL! :)
September 15, 200322 yr Some years ago (too many) when riding jump-seat in a 737-400, I had an interesting conversation with the crew about landings. As I recall, they told me that for a full autoland the autopilot is programmed to perform a 'positive landing' - which means, once down we want to stay down. Thus it is a fairly hard landing with little flare/float. To demo this they did an autoland into 27R at EGLL (even though it was CAVOK), and wow! you could feel the thump and hear your teeth rattle. That's how it's designed to work.For this reason, they said, almost all crews will hand-fly at least the final part of the approach and the landing, and many take it as a matter of pride to do a whisper-soft touchdown. As to how long they'll hold off, or let her run after touchdown, other things being equal that will often depend on what's the shortest distance to the terminal...If I might be impertinent enough to make a suggestion to some of our fellow Captains with the PMDG 737: do try switching off the computers and the autos and just try FLYING this baby! She handles like a dream and the sheer delight of hand-flying a non-ILS approach with a 20kt cross-wind and then touching down right on the centreline has to be experienced to be believed... oh, well done, PMDG!- Pete
September 17, 200322 yr "As I recall, they told me that for a full autoland the autopilot is programmed to perform a 'positive landing' - which means, once down we want to stay down. "Interesting, Pete...The Boeing Maintenance Manual says flare is supposed to give you a smooth landing. Imagine how how bad it would have been for you if Boeing had actually programmed the A/P to give you a hard landing :-lolCheers.Ian.
September 17, 200322 yr I wish a real 73 pilot would join in on this one, because all I can do is try to recall what happened - and a lot was happening - and do a bit of speculation.For a 'positive landing' you want to avoid all possibility of gusting wind or other external events influencing the aircraft once it's landed. So I speculate that what happens on the autoland is a nice smooth flare, followed by touchdown of the main gear, followed by quickly dumping as much lift as it can. That would bring the nose down fastish, which would account for the thump and rattle, me being up in the pointy-end at the time.Whether this is correct, or just pure hogwash I do not know. BTW has anyone ever seen any impure hogwash? :-)- Pete
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