Without a calibrated length scale and information on the frame-rate a video proves very little about the vertical speed. Additionally just because a real world pilot landed a certain way once on camera doesn't mean that was a good landing. Boeing recommends touching down at between -120 fpm and -240 fpm.

Soft landings are bad practice you say? Then how come so many landings are so incredibly soft?

Arjen...you are looking at videos, "from the outside of the aircraft", you are not looking at the PFD, at the vertical speed indicator. There's no way anyone can judge the vertical speed by guessing.

 

There was a TV show I watched a while ago, where a 737 pilot remarked that passengers often asked him why the landing was firm. He remarked that the objective in an airliner is to land in the right place, and firm enough to deploy the spoilers.

 

There have also been conversations on Avsim regarding this, one quite recently, where real world pilots confirmed that the greaser is not a good idea.

 

There's enough evidence on youtube that airlines land extremely softly, but don't grease/float. Again, I define them as two completely different things. I don't float in FS either, but do land softly

External view on Youtube is not evidence. In addition, you have no idea if that particular landing was a one of, or general practice.

 

Grease/float/soft landings are not "different things" they are simply different sink rates. From zero and thus floating, to a minimal sink rate. The danger of "aiming" for a mere -50fpm landing is that if you get it wrong [quite easy] you may float. And unless the laws of physics have suddenly changed, a -50fpm sink rate eats up more runway than a -300fpm sink rate.

 

Of course, too soft is not good because of the speedbrakes, but -100 ft/pm is optimal: not too hard and not too soft.

Err... no, you said -50fpm, not 100. You have now doubled the vertical speed.

Remember Captain Lim?

 

This is what he has to say about the optimal vertical speed for landing.

 

However, when you are about to touch down, your vertical speed must be progressively reduced as you start to flare ? something like "300 to 400 feet per minute". In fact, on a visual manual landing, you no longer look at the instruments, but feel with the so-called ?seat on your pants? to achieve a soft landing.

http://www.askcaptainlim.com/-flight-simulator-pilot-46/113-how-would-you-achieve-a-soft-landing-on-a-plane.html

Without a calibrated length scale and information on the frame-rate a video proves very little about the vertical speed. Additionally just because a real world pilot landed a certain way once on camera doesn't mean that was a good landing. Boeing recommends touching down at between -120 fpm and -240 fpm.

Yep, I'd agree with that John.

 

-120 to -240 would be a soft landing. Of course, on a wet runway or a short runway, you would aim for a higher vertical speed to enhance breaking. You want the full weight on the wheels asap.

 

If Arjen had said -120 initially I wouldn't have commented. But of course he initially advocated -50fpm.

The first landing (Air China A330) in the second video was really quite bad actually. By that, I mean that even though the wheels touched the ground early on, watch how long the pilot holds the leading edge axles of the main bogies off the ground. That entire time, no spoilers are deploying and no braking is happening. That pilot must have eaten up at least 1000 feet from the start of the flare to when the spoilers actually deployed. Yes, it may have been "soft" but by no means was that good.

 

(I deleted this paragraph because it was stupid...)

 

My completely uneducated opinion is that instead of doing a quick flare starting at 10 feet - which requires EXACT timing to prevent a float or hard landing - you should aim for a more gentle flare starting at around 30 feet. That gives you just a little more time to adjust for a sudden gust, etc. And aim for about -100 to -150 fpm.

I believe you are correct. Don't forget I never suggested to Martin that -50 ft/min was good. I just suggested that V/S doesn't necessarily tell anything about whether you floated or not. If a pilot pulls into the flare gently at 50 ft and lands with -300 ft/min, then he might as well have floated more than a pilot pulling up at 30 ft and landing with -100 ft/min. Get what a I mean? Your location of touchdown depends on your technique and moment of flare, rather than your final V/S. 

 

Of course, -50 ft/min is not good, the speedbrakes might not deploy, but I never suggested that it was. Personally I always aim for a -100 ft/min in the NGX which is very sufficient look at the replays and outsides views comparing it to the real world. 

 

With flaring "late" I didn't mean as late as 10 ft, that's way too late. I've been watching closely at 737 landings from the cockpit and I always notice the pilots start to flare very very slightly at 40 ft to bleed a little bit of V/S off. Then at 25 ft they pull a bit harder for a moment then release the pressure, and how the airplane levels off. At 5-10 ft, last corrections are made. 

 

In the 777, I guess -150 ft/min would be optimal. It wouldn't feel as hard as in the 737 anyway as far I can would guess. I think the main landing is gear is spring loaded in a horizontal way if you know what I mean. So if the leading edge touches the ground is sorta smooths out the touchdown as the gear goes flat and in the 737 that is not possible. 

I'd say that a float is when the aircraft balloons or is level/gaining altitude as opposed to losing it, in terms of an actual landing a soft landing is going to be preferred to a hard landing obviously because of the damage potential and the wear on the structure + tyre/gear assembly. There is no key fpm to achieve for a perfect landing because it is impossible to measure (in the cockpit anyway) in such small numbers as it can change so easily. All landing technique is procedural using height and speed to determine the time to flare and providing it is followed the aircraft will land either soft or just fine. All eyes really should be on the runway in the final seconds of flight, V/S is mostly insignificant when a procedural technique is used, it is the first thing taught at flight school when landing. On the PFD and in actual flight it is impossible to target any V/S anyway because it isn't even visible. The whole idea of GPWS callouts is so that pilots can use the callouts as aural clues to flare, idle etc.

 

The autoland system for example doesn't try to achieve a specific landing V/S or similar it will simply flare at a specific height, the engines idled allow for the speed to then bleed off naturally raising the nose without risking ballooning before finally touching down. This sort of method should really be the only thing the pilot tries to achieve, that and controlling trajectory to hit the touchdown markers. Anything else is trying too hard or trying too little.

I'm not going to join in the debate (what?!?!?) but I will say that VAs didn't do anyone any good by adding those stupid V/S at Touchdown statistics and making it a competition...

 

Is why im trying to get landings smoother because some VA's penalise on high V/S touchdowns, is it realistic?? I dont know.???

Was on aprroach to OPLA one minute in the clouds next min....bang on the runway didnt have time to flare or anything....VS was recorded as -768FPM landing,which is bad I know - and as I was taxiing actually had a Tire Pressue warning on the 777 again its realistic, however smooth landings is somethng I have always aim for for the very reason above.

I just suggested that V/S doesn't necessarily tell anything about whether you floated or not.

 

I didn't say it did Arjen, a float is zero vertical speed. What I said was that "the attempt" to land with such minimal vertical speed increases the likelihood of floating. All it takes is a fluctuation in wind, or miss timing and a float is possible.

 

Of course, -50 ft/min is not good, the speedbrakes might not deploy, but I never suggested that it was.

 

 

 

I believe you are correct. Don't forget I never suggested to Martin that -50 ft/min was good.

 

 

 

This was what you said...

 

However if you decide to land a bit more realistically by flaring later: 50...40...30...20...10...***soft -50 ft/pm landing***,

 

 

Quite clear you are referring to a -50fpm landing as a "realistic" landing. If you refer to a -50fpm as "realistic" you are advocating it.

 

 

In the 777, I guess -150 ft/min would be optimal.

 

 

Wasn't what you advocated initially. See above. Hence why I commented. You didn't mention -100fpm until page 2.

I'd say that a float is when the aircraft balloons or is level/gaining altitude as opposed to losing it, in terms of an actual landing a soft landing is going to be preferred to a hard landing obviously because of the damage potential and the wear on the structure + tyre/gear assembly.

 

 

I agree. A float would be defined as zero vertical speed. 

 

A soft landing is preferred as long as it's firm enough to deploy the spoilers, firm enough to enhance braking, doesn't eat up too much runway  etc.

 

Conversely, as you say, a heavy landing increases the risk of damage.

 

A good landing is somewhere in the middle. Interesting how Captain Lim, a 777 pilot I recall, advocates -300 - -400 fpm, as a "soft" landing.

 

I read this morning how no specific vertical speed is advised in regard to a heavy landing. Pilots are advised to judge the landing by how it feels. If it feels like a ton of bricks checks are required. I don't know how widespread that philosophy is.

Hey,

did you notice that flaring with the T7 takes you more pulling on the yoke? I am landing at the correct vref speed but need to flare way way more then the NGX. thoughts?

Just wondering how much fuel are you landing with and what is your CG if you have alot of fuel or have a forward CG you will have to pull harder in the flare I usally land the 777 with 18k-25k on board

With flaring "late" I didn't mean as late as 10 ft, that's way too late. I've been watching closely at 737 landings from the cockpit and I always notice the pilots start to flare very very slightly at 40 ft to bleed a little bit of V/S off. Then at 25 ft they pull a bit harder for a moment then release the pressure, and how the airplane levels off. At 5-10 ft, last corrections are made. 

 

In the 777, I guess -150 ft/min would be optimal. It wouldn't feel as hard as in the 737 anyway as far I can would guess. I think the main landing is gear is spring loaded in a horizontal way if you know what I mean. So if the leading edge touches the ground is sorta smooths out the touchdown as the gear goes flat and in the 737 that is not possible. 

Okay, now both of these paragraphs are what I try to achieve. In my entire simming days (back to glorious FS5), I have always had a tendency with big jets to kind of "pre-flare" at around 40-50 ft. I always got away with this until the PMDG MD11 came along and I found myself either floating or going 50..40..30..20..(*oh ######*)..10....bang, bounce, porpoise, etc. With the MD11 it takes a smooth full pull starting at 50ft to accomplish 100-150 fpm. Then the NGX happened and I started floating all over the place. I've found that starting a normal flare at 30 feet along with simultaneous reduction of power to idle gives the best results. This is very hard to do correctly though. I "cheat" a little if the runway is long enough and reduce VS to about 500 or so at the threshold then finish the flare starting at 20 in conjunction with idle reduction. This is much smoother and easier only if runway allows. I'm not afraid to touch down on the aiming bars at 200 fpm if it's somewhere like HOU or MDW though.

 

As for the 777...it seems to very much need the "perfect" technique. Start a "preflare" at 50 feet and you'll float float float. It really takes a perfect 2-3 degree pitch up starting at exactly 30 feet to get an optimal touchdown profile. I do think the idle reduction starts late though as well. I remember when the NGX came out and everybody was up in arms about how hard it was to land and lo and behold, PMDG found an issue with the dynamics. I'm wondering if something needs to be tweaked with the T7 as well because it seems as if the power stays on forever when using the A/T as Boeing recommends.

.......blah blah........

 

As Boeing say, FLY it onto the runway. The flare is merely supposed to arrest a 700 ft/min rate of descent to something around 300 ft/min.

 

Greasing it on *IS* bad practise, because you want those WoW (weight on wheel) switches in the bogies to actually *DO* something, like say, cause the spoilers to extend, so you can get the weight of the aircraft on those wheels so the brakes can actually do their job of stopping the aircraft.

 

If you have a contaminated runway, you have many more reasons to put it down firmly, not least so the tyres can break surface tension of standing water (for example) and get some grip.

 

This video here is an example of how *NOT* to do it!!!!!

 

 

Look how long it takes for the spoilers to extend, he keeps the nose up for what seems forever, and meanwhile he is unable to start slowing the aircraft. A great way to run off the end of the runway. It's Air France. 'nuff said. <_<

 

Best regards,

Robin.

 I'm wondering if something needs to be tweaked with the T7 as well because it seems as if the power stays on forever when using the A/T as Boeing recommends.

 

Me too! I figure it's throttling back at 15 feet instead of 25.

.......blah blah........

 

As Boeing say, FLY it onto the runway. The flare is merely supposed to arrest a 700 ft/min rate of descent to something around 300 ft/min.

 

Greasing it on *IS* bad practise, because you want those WoW (weight on wheel) switches in the bogies to actually *DO* something, like say, cause the spoilers to extend, so you can get the weight of the aircraft on those wheels so the brakes can actually do their job of stopping the aircraft.

 

If you have a contaminated runway, you have many more reasons to put it down firmly, not least so the tyres can break surface tension of standing water (for example) and get some grip.

 

 

 

Best regards,

Robin.

 

 

Thanks Robin, I agree entirely. Interesting that Captain Lim, I quoted above, recommends -300 fpm as well.

 

I

Just like the OP, I have noticed that in certain cases the FBW goes a little crazy, in terms of amount of back pressure required. It's been acting fine for me, but yesterday I decided to take off again after I had been at the gate, fly the pattern, and come in for a landing, but for some reason, the plane just wouldn't pitch up on final. I was applying full aft pressure, but the nose was barely raising. This is in contrast to my other flights where the airplane actually responded to pulling on the yoke. I did notice that, even though my Vapp was 142, for some reason, the PFD had me stalling at around 160 knots. Maybe this is related? I really don't know what happened yesterday, so I decided to go around and retry the landing, and the same phenomenon was occurring. Thus, I switched of the flight computers, and the airplane began to respond correctly to aft yoke again (although I flew my whole short final with stick shaker active, because my Vapp was lower than my stall speed for some reason). Hopefully someone can reproduce this so this little bug can be ironed out. I myself haven't been able to in the last flight I did.

Unless wx dictates I go fully manual at the 2,500 call out. What I am struggling with is having the proper trim setting set.

 

Sent from Samsung Galaxy Note 2