Pitch during touchdown

[Emi]

I've got the 172 since quite some time now and I really like it, but one thing bothered me all the time.

On final I simply get the impression my pitch is too low.
In the real world I fly the 172 down to the runway with a pitch of about 1-3° (depending on the conditions of course) with a flapsetting of 20 and an approach speed of 70kt. Then for the touchdown I reduce the power to IDLE and slowly pull the pitch up to about 10° maintaining a continious descent until I touch down.

In the A2A I have a pitch of about -5° during approach. Crossing the threshhold (of course depending on the exact condition it may vary a bit) I pull the power to IDLE, but if I keep pull the nose up the aircraft immediatly climbs.
I often even do nosewheel landings in the simulated Cessna, while in the realworld this has never happened to me.
All in all I got the feeling the A2A C172 got a very strong ground effect which I honestly never really noticed in the 172 irl at all. The real ones (at least the two in my club) rather want to drop to the ground if I reduce my speed during the flare. I would even say it tends to get a tailstrike during landing while in the sim it will immediatly start to climb again if I pull a positive pitch.

I already checked the forum and found this answer: http://a2asimulations.com/forum/viewtop ... 07&t=41261
Reading Lewis response in there makes me wonder though.
What are the differences how the 172R should be touched down? If I approach with the typical 70kt and then start to flare until I run out of speed I can easily eat up 500m or more which makes it impossible to land on shorter runways. In the real world I usually set go around power passing the runway half marking without having touched down.
Basically, being at the same weight and flap setting should at least deliver a similar result compared to the model I fly in the real world. A few degrees of pitch difference are ok, but that much? Surely there must be something I miss there.

I practiced several touch and goes over several hours today (arrived at home at 4PM today and flew until about half an hour ago (around 11PM!)), but couldn't get it right.
It surely shouldn't be soo difficould getting used to it, expecially since I have much experience flying simulated aircraft, as well as in the real 172.
With other simulated aircraft, including your PA28, I did never have such problems adapting to their flight dynamics (I of course do not want to say it's your 172's fault here!).

Is there anything special I should keep an eye on in the simulation compared to the real one, or is this behaviour maybe even intended? If so, why?
I have read you did many measurements in the real one, so I wonder if yours was really this different to the ones I fly?
Looking forward to your replies!
With best regards
Emanuel Hagen

[ravagetalon]

Try flying your final approach at Flaps 30 and 60 KIAS, power to idle crossing the threshold and flare at about 10 feet AGL.

[DHenriques_]

I've got the 172 since quite some time now and I really like it, but one thing bothered me all the time.

On final I simply get the impression my pitch is too low.
In the real world I fly the 172 down to the runway with a pitch of about 1-3° (depending on the conditions of course) with a flapsetting of 20 and an approach speed of 70kt. Then for the touchdown I reduce the power to IDLE and slowly pull the pitch up to about 10° maintaining a continious descent until I touch down.

In the A2A I have a pitch of about -5° during approach. Crossing the threshhold (of course depending on the exact condition it may vary a bit) I pull the power to IDLE, but if I keep pull the nose up the aircraft immediatly climbs.
I often even do nosewheel landings in the simulated Cessna, while in the realworld this has never happened to me.
All in all I got the feeling the A2A C172 got a very strong ground effect which I honestly never really noticed in the 172 irl at all. The real ones (at least the two in my club) rather want to drop to the ground if I reduce my speed during the flare. I would even say it tends to get a tailstrike during landing while in the sim it will immediatly start to climb again if I pull a positive pitch.

I already checked the forum and found this answer: http://a2asimulations.com/forum/viewtop ... 07&t=41261
Reading Lewis response in there makes me wonder though.
What are the differences how the 172R should be touched down? If I approach with the typical 70kt and then start to flare until I run out of speed I can easily eat up 500m or more which makes it impossible to land on shorter runways. In the real world I usually set go around power passing the runway half marking without having touched down.
Basically, being at the same weight and flap setting should at least deliver a similar result compared to the model I fly in the real world. A few degrees of pitch difference are ok, but that much? Surely there must be something I miss there.

I practiced several touch and goes over several hours today (arrived at home at 4PM today and flew until about half an hour ago (around 11PM!)), but couldn't get it right.
It surely shouldn't be soo difficould getting used to it, expecially since I have much experience flying simulated aircraft, as well as in the real 172.
With other simulated aircraft, including your PA28, I did never have such problems adapting to their flight dynamics (I of course do not want to say it's your 172's fault here!).

Is there anything special I should keep an eye on in the simulation compared to the real one, or is this behaviour maybe even intended? If so, why?
I have read you did many measurements in the real one, so I wonder if yours was really this different to the ones I fly?
Looking forward to your replies!
With best regards
Emanuel Hagen

Try not to fly your approaches so regimented and locked into set numbers. Be a bit more flexible in the air.
Try flying the approach referencing the runway and simply adjust your power, configuration, and airspeed to arrive over the threshold at the right altitude and airspeed.
As you get better with doing this you will eventually and naturally simply "slide" into flying a stabilized approach that is optimum for your airplane. But for starters, just referencing the runway will keep things a lot less complicated for you.
So from your downwind on, it's the runway threshold and what you have to do to get there set up to land.
Dudley Henriques

[Emi]

Hi Dudley,

thanks for the advise, actually that is what I do already though.

I just gave the numbers for you to see if they look rather common or uncommon to you (I remember those problems where ASN wouldn't let you land in P3Dv2), in order to check if there may be something wrong in my simulation.

Basically I of course simply have a look at the runway and adjust things accordingly without looking too much (well, rather rarely actually) at my instruments.
I do have a stable approach without to many adjustments necessary, so the approach shouldn't be the problem.
The problem in the simulation is that once I get close to the runway I got the feeling of having to much lift, like flying through an updraft. Therefore the pitch becomes to low which can often lead to a nosewheel landing.
I tried with, and without, ASN, so I'm rather sure it's not an updraft problem.

Do you have any recommendation how to touch the 172R down?
Basically there are two methods I'm used to from the real world:
Either fly the aircraft down onto the runway (works perfectly in real life!)
Or flare it until it's out of energy and drops the last few centimeters (I don't really like this technique IRL).

Either of these does not really work in the simulation as they would do in the real world though.

[aprewett]

I have had the same problem, following the published guidelines.
The flare ended in a long slow descent, eating up runway and always overshooting my intended touchdown point.
My current solution is to slow the plane right down. I land under 60, anything over just did not work in a controlled manor.
Allan

[Scott - A2A]

My current solution is to slow the plane right down. I land under 60, anything over just did not work in a controlled manor.
Allan

This is correct.

The angle of attack in the sim is within a degree of accuracy from the actual plane, and I think this is mostly perception. Try landing on a very large runway or grass field, and go to the outside view and slow the plane down to flare speeds. What you will see is the same angles and descent rates as you would see if you were sitting on the runway watching 172's land.

Scott.

[aprewett]

Hello Scott,
You say this is correct, but I thought the published speed was 64-70 with full flaps?
I have found at those speeds my landings are hopeless.
So I have been doing the glide slope approach probably around 50-55.
Then the flare and touchdown don't seem to drag on to long.
Thinking about it, part of the problem could be different yoke sensitivity setup's.
I find it very easy to over pull up on the flare and start climbing as the original poster mentioned.
Sorry if I have hijacked the thread.
Allan

[Great Ozzie]

Hello Scott,
You say this is correct, but I thought the published speed was 64-70 with full flaps?
I have found at those speeds my landings are hopeless.

Hi Allan,

Book numbers for flaps is 60-70kias. But these numbers are for max weight. You will naturally get a little more float if flying a couple hundred pounds lighter (e.g. with just the pilot) if no compensation in airspeed is calculated.

[AKar]

Rob says precisely what used to trick me for long. The speeds are often for maximum weight but my usual landing weights in the simulator may be for example from 10 to 20 % below that ... that weight means around 5 knots reduction at Cessna speeds.

Of course, ground effect may play tricks too if you're too fast (it decreases drag, which may get important if even slightly too fast, though it may also increase stall speed a bit especially on low-wing airplane and flaps down, and it usually causes that some extra aft elevator is required compared to out-of-ground-effect maneuver.)

-Esa

[DHenriques_]

Hi Dudley,

thanks for the advise, actually that is what I do already though.

I just gave the numbers for you to see if they look rather common or uncommon to you (I remember those problems where ASN wouldn't let you land in P3Dv2), in order to check if there may be something wrong in my simulation.

Basically I of course simply have a look at the runway and adjust things accordingly without looking too much (well, rather rarely actually) at my instruments.
I do have a stable approach without to many adjustments necessary, so the approach shouldn't be the problem.
The problem in the simulation is that once I get close to the runway I got the feeling of having to much lift, like flying through an updraft. Therefore the pitch becomes to low which can often lead to a nosewheel landing.
I tried with, and without, ASN, so I'm rather sure it's not an updraft problem.

Do you have any recommendation how to touch the 172R down?
Basically there are two methods I'm used to from the real world:
Either fly the aircraft down onto the runway (works perfectly in real life!)
Or flare it until it's out of energy and drops the last few centimeters (I don't really like this technique IRL).

Either of these does not really work in the simulation as they would do in the real world though.

Rob and AKars might have nailed the issue for you. Depending on your actual landing weight, anything below the published GW will effectively alter the actual landing speed. If you're light and using the listed IAS you may very well be over the fence too fast and experiencing the ramifications evolving from that during your flare and landing.
Also, I think I might be seeing something else in what you are saying. You reference the aircraft "doing this" or "doing that". This indicates to me you might be allowing too much leeway to the aircraft "doing something" as opposed to YOU not allowing the airplane to do that. Remember, in any landing, and actually in ANYTHING connected with the airplane while in motion, when you factor in wind, it's ALWAYS an ongoing "battle" between you and the airplane concerning what the airplane is doing and wants to do at any given instant. Make absolutely sure YOU are in charge of that "battle".
If at any moment while you are in flight and the airplane is moving in 3 dimensional space or even on the ground in motion, if the airplane is doing something YOU didn't initiate or desire, start looking immediately into why that is happening, why you let it happen, and what you need to be doing to stop that from happening.
Bottom line on what I'm getting at here is that during your landing, the aircraft shouldn't be doing anything "on it's own".
I only mention this as a reminder. Try reassessing what's happening on the landings and see if there's something you might be "allowing" the airplane to be doing where you could stop that from happening.
Dudley Henriques

[Sazoga]

I also overshooted the runway/touchdown point or even climbed at my flare, so 60 KIAS is just too fast. With arround 45 KIAS and a very very slow flare, everything's fine. But yeah, the C172's landing is very hard to learn (for me).

[Oracle427]

If you are flaring at 60 kias, you are going too fast. The approach is done at around that speed, but by the time you reduce the power to idle, begin the glide break and level off over the runway, your speed should be down low near the bottom of the white arc. The flare is just scrubbing off the very last bit of that remaining airspeed. At 60 kias the flare will make the 172 climb away.

[DHenriques_]

If you are flaring at 60 kias, you are going too fast. The approach is done at around that speed, but by the time you reduce the power to idle, begin the glide break and level off over the runway, your speed should be down low near the bottom of the white arc. The flare is just scrubbing off the very last bit of that remaining airspeed. At 60 kias the flare will make the 172 climb away.

I would respectfully add a caveat to your already correct comment if I may.

Although too fast, it should be completely understood that this doesn't necessarily mean the airplane will climb.
It doesn't have to climb and won't if held in the flare. The result will simply be a longer flare due to the excess airspeed. This is something we always stressed to student pilots entering the landing phase.
The flare is simply accomplished from whatever airspeed you have entering it until you have scrubbed off enough airspeed to land the airplane. Obviously the flare is optimized by you beginning it at the right airspeed, but if you are hot over the fence but not hot enough to cause a go-around decision (say a few knots extra airspeed), you perform your flare the same way but the flare will be longer on that landing.
Once in the flare.....ANY flare.....you simply don't allow the airplane to climb by HOLDING IT in the flare as the airspeed decreases on that longer time line.
Dudley Henriques

[Oracle427]

Yes, totally agree and I did get that wrong. The flare is not a steady pull back on the yoke with no regard to what the aircraft is doing. A properly executed flare will fix that aircraft right over the runway until it is done flying!

[DHenriques_]

Yes, totally agree and I did get that wrong. The flare is not a steady pull back on the yoke with no regard to what the aircraft is doing. A properly executed flare will fix that aircraft right over the runway until it is done flying!

You were BTW totally correct that (IF ALLOWED) an aircraft flared with excessive airspeed will climb. I think both you and I simply want to stress that this doesn't have to be the result if the airplane is properly held in the flare.
)
DH