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ahinterl

Landing technique

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I'm no physician, nor is it easy for me to reproduce an appropriate situation and test accordingly, so I thought I ask the experts here:Let's say you're (way) too high with your airliner during the last 100-200 ft. Using either of the below maneuvers, would the result be the same and the main gear touches down at the same location down the runway?1. Strongly dive with a negative pitch, then at approx. 30-50 ft firmly pull the nose up again to get a "normal" sinkrate back (I know, it's questionable whether the structure of a real plane could withstand the massive stress that occurs here), then float to dissipate the excessive speed built-up during the descend2. Land as normal farther down the runway because of the too-high approach.Andreas

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Guest marxy

Hmm,in such a case I would perform a go around and come back for another approach.The first idea you suggest is not safe since it puts a lot of stress on the aircraft and if the flare is done slightly too late you will be in big difficulties. . . . . .The second idea to land long is only tenable if there is a really long runway and it is safe to land further down it. This comes to a head when using smaller airports with marginal aircraft (such as a 757 with newcastle airport or similar)So, to sum up, I suggest the go around as the procedure of choice (if that is the right way to think of it) and if I had to pick either of your suggestions I'd go with the second one provided the runway is long enough and the weather conditions allow (dry for braking etc)

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Considering just the physics (which would make us physicists), in theory, yes. All things being equal, the touchdown point would be the same.HOWEVER.. all things aren't equal, and an airplane is a much different element in ground-effect. That dive would result in higher airspeed when entering ground-effect, hence an extended "float", before you'd be at a safe airspeed for allowing it to stop flying.

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Andreas Very good question, and one that most of us flight simmers and real world pilots have to consider. After the accident in India, I read an interesting article that talked about "stable approach". I think it applies to your question.When approaching the runway your speed must be in the landing envelope. Next flaps should be fully deployed, and stable direction.I fly the LDS 767 and attempt to do these 3 things on every approach. Your question on diving is a very bad technique. Your landing speed will increase beyond the landing speed envelope and as another poster indicated you will float and worse case if your flare is too late you will cream into the runway, which will overstress your aircraft or even worse collapse the landing gear.Your second point about landing normal but further down the runway could work on a long runway 8K feet+, but VERY bad technique.This is what a "GO AROUND" is all about, the stable approach items that I mentioned if not satisfied then GO AROUND. Remember these become even more critical during snow, rain or crosswind conditions.When I was in the USAF we practiced "touch and go's", good thing for you to do in FS. One thing I have noticed in the MSFS world is people loving to switch planes, this is really not real world, you don't have type ratings in numerous planes. By becoming very proficient in one or types your technique improves.Good point, but the key is Practice and more Practice.Good LandingsBobKDTW

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I am no RW pilot, but my choice is to hit the TOGA switch and try again. Every time I am flying on published approaches, I do study missed approach procedures and get ready for it as soon as practicable - it is much easier with MCE - You just tell Your virtual Co-Pilot to set the radials, radios and set the altitude to climb to in case of missed approach, while controlling the Aircraft. It is better to be 15min late then to arrive in pieces

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The thing with doing that 'dive it' technique is this: It is definitely possible to do it, but if you get it wrong, you'll be sorry, and I speak from personal experience here. Flare too late and you'll hit with too high a descent rate and overstress things, not to mention possibly putting far too much G on the passengers for their comfort. Flare too soon and you'll balloon and possibly end up stalling off that ballooning pitch up when the wheels are quite a long way off the deck, which will also drop you down with a hell of a jolt.I did the former of those two once when attempting a greaser in a two seater aircraft. It was when I was a fairly new pilot and I'll admit that I was an over-confident cocky git that thought I was brilliant at landing and could flaunt with the correct technique, which I found out was not the case. It was a pretty 'solid' arrival, and I only mis-timed it by about half a second, but it was enough to cause a problem. That landing actually cracked a GRP cover of a wheel fairing, but fortunately, apart from that and a bit of a sore back for the guy in the other cockpit (it was a tandem layout aircraft I was flying), there was no damage. After that I revised my landing technique so it would never happen again, and considered it a lesson well learned and was extremely chastened by the experience, not to mention thoroughly embarrassed at jolting the passenger's back, which fortunately did no permanent damage to him.But if you did that with an airliner, and fare-paying passengers, it would probably be your last flight as a commercial pilot.Remember that part of your descent briefing is to look at the airport chart and know how long the runway is. When you know that, you will also know if you can get away with landing a bit long. Note that the white markings on the runway are spaced at 500 foot intervals, so you can use that to gauge how far down it you are if you do land a bit long, and you should be aware from that if you have enough runway surface left to safely brake to a halt.Al


Alan Bradbury

Check out my youtube flight sim videos: Here

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Personally, I'd try a sideslip - depending on different factors, of course.Seem to recall the story of the Ginli Glider - and IIRC, he ultimately did a sideslip to bring the 767 down on the runway.Probably would be the safest way to go, other than going missed.Vic


 

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Personally, I'd try a sideslip - depending on different factors, of course.Seem to recall the story of the Ginli Glider - and IIRC, he ultimately did a sideslip to bring the 767 down on the runway.Probably would be the safest way to go, other than going missed.Vic
Obviously a go-around is the best solution if things get that far out of hand that a dive to the runway is the only obvious way to get to the runway. The FAA regs say that you should be in a position to make a normal landing (this is part of an IFR regulation that allows a landing if certain criteria are met).However, if you are very low on fuel and may not survive a go-around, then the best solution is perhaps the least intuitive. You want to slow down so pull back on the yoke to maintain altitude, drop the flaps as soon as possible and make a landing. You will now be in a situation where you an make a short field landing, which is all you may have left of the runway!!As my CFI told me many years ago in a situation just like this that he maliciously created to demo this scenario (".......If you absolutely had to land what would you do now.."). It goes like this :"If you want to go up, pull back. If you want to go down, pull back harder".Bruce.

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Thank you for all replies. In real life, I'd stay on the safe side of course and never even think about diving the plane.When I watch videos of landings at LPMA or MHTG, I often have the impression that many pilots simply ignore the possibility of a go around. The brute force maneuvers they perform are embarassing even when viewed from the outside. Do they really loose their jobs?Andreas

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If enough passengers complained about an incident, it would certainly not look good on a pilot's record, and from a PR standpoint that thing is not good, so yes, they could lose their job.Al


Alan Bradbury

Check out my youtube flight sim videos: Here

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Sometimes pilots ignore that possibility, and they stay alive just on dumb luck.I recall a USair video in which a 737 almost went off the runway at Toncontin.Here's pretty much what an airport like that boils down to though - High stress levels on the pilot. It's easy to make a 737 dive when it has it's flaps out you just push the nose down five more degrees and it goes astronomical in the FPM department. Airspeed will increase with that sortof high descent as well. When landing an airplane - especially at an airport like toncontin, Less information is derived from the Flightdeck, more information is derived from outside the window. He pushed the nose down in the descent gained too much speed and he went long. Landing at Toncontin is easier said than done, and if you fired every pilot who did a mediocre landing at that airport - None of your pilots would want to fly there, infact they'd probably dread the idea.It comes down to decision making, as many things do in aviation. A few months ago I was flying the archer you see in that picture and due to a lack of visibility (Bright sun, and a light layer of "Smog") creating eh 10 miles of actual vis, (but more like 5-7 after the sun). I had difficulty identifying Montgomery field as well as the location of the airport to my left (Gillespie). As not to descend into gillespies class D, I maintained my altitude and then started my descent into montgomery once I spotted the the field (Generally I would start before this since the Class D is at 2400 at Gillespie - That's a 600 foot clearence to kill on the way to Montgomery - You can generally descend and get yourself lower by the time you reach the lake). Now at 120 knots and 3000 feet over lake murray you're about 5 miles to the runway.2 miles per minute that's 2 minutes 30 seconds to arrival at the airport(Straight in approach as coming from the east you're well ligned up to just go straight down to the runway and land. At 120 knots you're doing oh 1000FPM or something. that's still not fast enough of a descent to put you on the runway.Now this is a really awkward situation - You're high, you're fast, your instinct is to push the nose down and descend faster, Which I did and got myself up to 130 knots or so (Where the airplanes flying like a really fast Rock). and even then - I was high. Couldn't slip at that point - too fast. Couldn't do flaps too fast, so I raise the nose about and get myself slow enough to get 10* of flaps in and decided - New trick. Slip it up.So I start slipping (I'm practically determined to get this thing on the ground, I've descended fast, i've gotten myself into a forward slip. )And then the moment of truth:100 feet too high, at about 90 knots, with flaps ten (Hand on the bar itching to pull that flap handle all the way) with 3400 feet of 60 foot wide runway in front of me.Not gonna happen - So I started raising the nose and applied full power. Told Montgomery tower I was going around and the second time was a charm.Now the trouble in particular with say something a bit heavier? if you're at the right altitude but too fast that "itch" to go around may not be strong enough to warrant it - It can be a false sense of security. The final moments are just about always visual, even in an IFR ILS approach, a place like toncontin where you have to visually put an airliner on the ground though - makes this ten times more difficult (Primary focus goes from inside the cockpit with instrumentation, to primarily visual reference with airspeed/attitude information.) Ultimately - you can or can't make it on the runway in a safe manner. The goal is to always be safe, but sometimes human error comes out and bad things happen.Fly Safe :( .

Thank you for all replies. In real life, I'd stay on the safe side of course and never even think about diving the plane.When I watch videos of landings at LPMA or MHTG, I often have the impression that many pilots simply ignore the possibility of a go around. The brute force maneuvers they perform are embarassing even when viewed from the outside. Do they really loose their jobs?Andreas

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