quote:

Originally posted by RHINOWSO:
Autopilot must have been Out of Service.

Heh!

I know you know, but it's still somewhat surprising even to me how much better human beings are than autopilots for landing in the wind. Steady state, the autopilot can do a good, if not smooth, job. In the wind, human senses and experience still rule, by a big margin.

A friend posted that on Facebook. My initial response, and I'm a 737 driver, was that his inputs were awful rough and exaggerated. That being said I didn't see outside and I wasn't there.

The huge inputs though were in and out so quickly that if I had to make my best judgement I would say he was over controlling and a lot of those inputs were negated by the immediate opposing inputs that he also did. I.e. Huge input one way followed by immediate huge input the other.

I have landed in big gusty winds. I have never placed a GoPro on the instruments to film myself. Maybe it does look like that. I think it doesn't though.

That Winter 2013/2014 I flew into Schiphol, when I saw the waves white capping I knew it was gonna be fun. Damn near could see the runway out the passenger window, it was a hoot. I love flying in those conditions.

quote:

Originally posted by pedropcola:
The huge inputs though were in and out so quickly that if I had to make my best judgement I would say he was over controlling and a lot of those inputs were negated by the immediate opposing inputs that he also did. I.e. Huge input one way followed by immediate huge input the other.

A very good description of what I was thinking and didn't actually communicate.

Is that what they look like?

I really need to keep my eyes open more...

quote:

Originally posted by entropy:
Is that what they look like?

I really need to keep my eyes open more...

You should see what they look like trying to land on of them there circular runways!!

quote:

Originally posted by entropy:
Is that what they look like?

I really need to keep my eyes open more...

I agree it looks like he is over controlling. I see guys pump the elevator in landing, like it is digital rather than an analog response. All they really need to do is make smaller, slower inputs.

Usually turbulence is a back-and-forth event in whatever direction it is working. If it is up and down, the ups and the downs are approximately equal. If it is a rolling motion, the leftward rolls approximately equal the rightward rolls.

Which means keeping a calm control column works well. Large deflections may be necessary, but they can be moderately slow in making those inputs. The fast, jerky way that guy in the video is moving the control column for the length of time he is doing it seems excessive from my experience, especially in terms of pitch.

All kidding aside, I toss my hat in with others stating he appears to be "working a tad bit too much". Theres a term for it..."PIO". "Pilot induced Occillations". Or...in the 'Bus using a stick its called "Stirring the pot".

When you make a control input, especially at low speed, there is a delay in its effect. Afterall, you are moving a (in this case) probably a 130,000lb+ mass thru space. Its not going to be instantaneous. If you look at his inputs, each is fairly quickly followed by a nearly equal opposite one...net result?? There isnt a whole lot of mass being deflected. There just isnt the time allowed with the control deflected. Make sense?

The Airbus, being FBW is a little different. In that Boeing, there are cables and pulleys attached to those control surfaces via hydraulic booster units of sorts. The Bus is all electrons baby. The result is moving the stick "commands" a roll rate or in the case of pitch a load factor. Its kind of a weird concept to wrap your head around. The end result for the pilot is unique though... There are quite a few times in rough conditions (especially on landing with full flaps) where you "hit the stop" with the sidestick. In otherwords, you move it left or right and literally hit the physical limit of the stick mechanism. There is no more to give! You have to wait in order for the computers to continue to input that maximum roll rate you just commanded. Trust me, its a lot scarier to do than it is to read. Lol. The only time the stick movement is "unfiltered" by the flight control computers is below about 50' on landing. Then it is a "raw" input so to speak. This is one of the reasons that technique dictates using partial flaps for landing in gusty conditions. There is less chance of "hitting the stops" since your overall controll effectiveness with partial flaps is a bit more "crisp". Full flaps, in any airplane, tends to allow the airplane to "wallow around" a bit.

Not gonna pick on the guy though. The Daily Mail article has a picture of him in an orange flight suit. Since I dont have, nor ever have had, an orange flight suit, I feel I dont have room to knock him. It also shows him sitting in what appears to be an Extra 300 or similar aerobatic plane. Ive never flown one of those, but imagine the size of the control surfaces and the "close coupled" effects of that would make flying it quite "crisp" indeed. It looks like he is trying to fly that 737 like he does that Extra.

Now back to having the flu again...


Oh. One more thing before the meds kick in: Autothrust/Auto throttles.

Double edged sword on these. They are really good at maintaining the speed you selected. However, when it is gusty you get sometimes large corrections by them as your airspped fluctuates with the gust. The autothrust is dumb though and doesnt realize its a natural rythum of events. They will try to maintain that speed. With wing mounted engines, thrust inputs tend tomcause the nose to lift (with thrust application) and drop (with thrust removal). You can see what is being set up here. Chase the exact speed with the autothrust results in pitch occillations. Somerimes its best to disconnect it, set a nominal thrust setting for speed, and ride the wave baby. Well...EXCEPT once again on the Airbus which has this thing called "ground speed mini" that REALLY helps with low speed energy management...but it only works with the autothrust on. Thats for another discussion.

This may have been posted quite a while ago, but here is a video of manufacturers testing the crosswind capability of their aircraft.

Watch the rudder movements on the 4th landing after the airplane is on the ground. This one is good viewed full screen with the sound up a bit for the music played.





Link to original video: https://www.youtube.com/watch?v=DYwO-I6FKHI

quote:

Originally posted by SigSAC:
Watch the rudder movements on the 4th landing after the airplane is on the ground. This one is good viewed full screen with the sound up a bit for the music played.

Just to put this in a bit of perspective. The nosewheel steers around 7 degrees either side of center when using the rudder pedals. I have experienced any number of cases where I had everything well stabilized in a high crosswind and then had to use a lot more pedal and rudder when the nosewheel touched down to keep the airplane traveling straight. Even though the rudder may have shown significant deflection, the nosewheel wasn't deflecting much at all. Similar things can be seen on takeoff when the engines don't spool up at quite the same rate.

Airbus much easier to land than the Boeings 777 & 757. No landing is ever the same. That's what they pay the big bucks for...SKILL.

quote:

Originally posted by SilverWolf:
Airbus much easier to land than the Boeings 777 & 757. No landing is ever the same. That's what they pay the big bucks for...SKILL.

That is because the pilot isn't landing the Airbus, he is directing the computer to land the Airbus.

quote:

Originally posted by PPGMD:

quote:

Originally posted by David Lee:
Nah, if that was Otto or Entropy, they'd be so smooth you wouldn't even see any movement, Because there wouldn't be any. Because they are 2 Sig Forum pilots.. . And that's different than a regular pilot.

I don't think Otto's passengers care about a smooth landing. The boxes don't scream.

LOL PPGMD..

No joke.

A few months back I had a brand new FA up front during a break. She casually asked me "Which button is the landing button?? Just in case something happens to you guys and I have to do it."

YEARS back (we're talking mid 80s) one place I worked at required all new flight attendants to sit for a minimum of one leg in the jumpseat. This was to acquaint them with our workload during takeoff and landing and give them perspective on the entire philosophy of "sterile cockpit" below 10,000'. I always thought it a good idea. The last place I worked did a lot of empty legs and ferry flights just as a part of the necessary operation. Always asked if anyone wanted to ride up front. Never got a decline. I remember one leg into a East Europe airport one night in heavy rain. Not a big deal, but a few bumps on final, plus the racket of the wipers running made quite an impression on the gal sitting behind us.

quote:

Originally posted by entropy:
I remember one leg into a East Europe airport one night in heavy rain. Not a big deal, but a few bumps on final, plus the racket of the wipers running made quite an impression on the gal sitting behind us.

Yeah it's all fun and games until someone turns out the lights and throws in some sweet ass weather, some wind, maybe some bumpies on the way down...

And those times you get some leans one way or the other, those were the best... One night we were approaching the boat, in similar condition to what you described above, and the whole way down the chute my internal gyro was telling me we were pulling nose high through vertical... all the while we were level until tipover... what a night....

Yea, its really amazing that out of all the time spent in the seat, there are certain events (some not a huge deal) that are burned forever into your memory. I can hear the wipers right now as a matter of fact...

Entropy mentioned Pilot Induced Oscillation, which reminds me of the first time I flew a Cessna 310, maybe 30 years ago.



The main fuel tanks on the C-310 are the tip tanks, holding 75 gallons, 450 pounds, each side. That's 900 pounds of fuel total, out there at the ends of the wings. A lot of inertia once they start moving.

It was a fairly calm day, just the normal Florida summer wind puffs, nothing interesting. My first take-off, as I cleared the tree line at the north end of the runway, a small gust caused a slight rolling motion, I corrected and it turned out I over-corrected, which required an immediate correction in the other direction. Rinse, repeat. I was rocking it back and forth, cursing, while the pilot who was checking me out in the airplane was laughing uncontrollably.

I finally said, "Screw it!", relaxed the death grip with my hands, and just used my feet for rudder pressure to stabilize things, and of course when I stopped fighting the airplane, everything settled right down.

Lesson learned: The airplane already "knows" how to fly. All it needs is some guidance from the pilot, to tell it where we want to go.

But you know what the strangest thing is?? My smoothest landings have occurred after a bumpier-then-hell approach down the localizer combined with gusty cross-winds 60* off the nose. Had people tell me they didn't even know we landed. Light airplane with calm winds? Yeah....I'll plow that bad boy on there almost every time. Make EXTREMELY good use of that trailing link landing gear.....

I was reading about the Navy system 'Magic Carpet' being developed for carrier landings

according to the author Capt. David Kindley, during the last 18 seconds of flight the average pilot makes 200 to 300 minor adjustments to the aircraft

with Magic Carpet, the pilot workload reduces to about 20

and the touchdown is at a leisurely 800 fpm rate of decent