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Can't seem to land anymore....


Animosity2k

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So I've got 120 hours in the CT and have never had any issues landing outside of my first few lessons. The last two times I have gone flying I have had huge issues sticking my landings. I was out the other day and had 4 bounced landings. Two of them I was stupid enough to let the plane bounce 2 or 3 times before going full throttle and around. The last landing I was finally able to stick it but when I landed I skidded all over. I decided to try again yesterday afternoon. Altimter 30.47, winds 070 @ 8kt taking off of RWY 6. Three attempts again to land resulting in three more nasty bounces. All I can think is that I added some extra air to my front tire a week or so back to match what was recommended on some of the threads here (I was a bit low before). Immediately after adjusting it I took a few flights and had no issues with bouncing. Fast forward a week or two and now I bounce every time. I'm so frustrated. Could lessening the front tire pressure help with this?

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I don't think so.

We have about the same number of hours and I run into this as well.  I flew every day for the past 7 days and the first 5 I was doing great(it was time do my night landings to stay current).  The last two days my landings just weren't as good.

My issue is that I started flaring a little too high and have a tendency to drop it in.  Those last two days I was traveling cross country so maybe it's fatigue.

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The first flights I was out with a friend flying at night (I'm a sport pilot but he's a CFI and I wanted to try flying at night) I think that had a lot to do with those bounces, I just was not used to the perception.

The second day, I just have no clue what I had going on. I just couldn't get it. I've had a lot of stress, girlfriend moved out of the house, works been stressful lately, and I've likewise been a bit fatigued so perhaps that added to it as well. 

I don't know, I just woke up thinking maybe I just lost it all and I need to sell the CT

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At 60k the airplane is still happily flying well above stall speed, and adding power at that point isn’t helping.  Lower approach speeds would help.  Find out your indicated stall speed in landing configuration. The usual method for determining approach speed is to multiply that by 1.3, and that produces a surprisingly low number for the CT.  It works, but it puts you behind the power curve and means you need to use power to arrest the descent. A factor of 1.5 or 1.6 might be more comfortable for you and provides sufficient margin. Full flaps helps, too. 

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17 minutes ago, John Vance said:

At 60k the airplane is still happily flying well above stall speed, and adding power at that point isn’t helping.  Lower approach speeds would help.  Find out your indicated stall speed in landing configuration. The usual method for determining approach speed is to multiply that by 1.3, and that produces a surprisingly low number for the CT.  It works, but it puts you behind the power curve and means you need to use power to arrest the descent. A factor of 1.5 or 1.6 might be more comfortable for you and provides sufficient margin. Full flaps helps, too. 

I really don't want to drag it in behind the power curve, little to much pucker factor for this guy

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80 knots and 0 degree flaps entering the pattern, 70 knots on base leg, when I get established on final I put in 15 degree flaps and look for 60 knots, I try to to keep it around 55 knots crossing the fence.  When I get below 20 feet above the ground, I stop looking at the gauges and do what feels right, this usually involves adding a small amount of power.  Works like a champ.  Sometimes you can get too caught up in the numbers and ruin a landing.  Sometimes flying by the seat of your pants is the way to go.

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First of all, I'm convinced tire pressure is a red herring - it should have minimal effect if everything else is right*.

A lot of our skills involve mental models and often the language we use reflects those models. It may seem like a small thing, but I immediately noticed that you articulate your goal as successfully "sticking" the landing. That's simply not how I visualize the landing process - more on that in a moment.

All the talk of pattern speeds is important, insofar as consistency and a stabilized approach is a good thing. But as long as you can arrive at a predetermined point on final - usually described as one wingspan above the ground - in landing configuration, at your target final approach speed and at or near idle, everything is set up for a proper landing. That final approach speed is typically 1.2 to 1.3 Vso. In a plane that stalls at 40 kts that would be 48 to 52 kts.

Once you get to that point, it should just be a matter of rounding out the descent and leveling off no more than a foot or so above the runway, then holding the plane off until the stick is fully back and the plane has no choice but to land. That should typically occur around 40 kts. To bounce repeatedly I think you must be touching down too fast, and the fact that you "skidded all over" on one  lends credence to excessive speed and energy on touchdown.

Figure 10-4 from Kershner shows what I mean:

7966212268_e30bb21314_z.jpg

Admittedly, there are those who hold that a CT is a strange beast that requires special techniques in the landing. I disagree. Though I don't have a lot of hours in CT's, my limited experience in them did not show them require any techniques out of the ordinary. My goal would be to try to get proficient with full stall, full flap, power-off landings. Power should not be required as a normal procedure. Yes, "flying it on" with partial flaps and a little power may make things "easier", but I think that sets the stage for touching down way faster than needed, with all the bad things that go along with the extra energy being carried.

Anyway, this topic comes up quite regularly, and the differing opinions border on "Never the twain shall meet". Regardless, a couple hours with a competent instructor will probably be more effective than any advice you might get here.

But good luck. One way or another it will sort itself out.

 

*Picture how you would land if you knew in advance that your nose wheel tire was flat - or worse, missing! I don't see any reason every landing shouldn’t be made that same way regardless.

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As an aside, I came up with a little Excel spreadsheet to calculate the increase in energy resulting from an increase in speed:

23659991808_0230491531_w.jpg

 

You can see the formula I used if you want to "roll your own". In another example, landing just 10 kts faster than needed (51 kts instead of 41 kts) results in a 55% increase in Kinetic Energy - energy that can and will be dissipated somehow if things go wrong. Worth thinking about.

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When I start having problems I go back to what the Western Distributer check pilot taught me. 

Next to the touch down go with flaps 30. At that point I am at 60K and throttle is closed. If you look at the drooped wing tip on the SW it will be level with the horizon if you are on speed. Once on final I use the book speed of 50K until flare. That speed is for 1320# so if you are less you may still get a little float but I don't recommend going any slower. Sometimes, at the bottom I may need to add a couple of hundred RPM to smooth out my lack of proficiency. All of this assumes good flying conditions. When it's turbulent and gusting and with a cross wind, you will need to adjust accordingly.

This is what the check pilot recommended and it made my transition from a C-182 uneventful. In fact, I didn't know I was supposed to have trouble landing a CT until I joined this forum.:giggle-3307:

 

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6 minutes ago, sandpiper said:

 

Sometimes, at the bottom I may need to add a couple of hundred RPM to smooth out my lack of proficiency. In fact, I didn't know I was supposed to have trouble landing a CT until I joined this forum.:giggle-3307:

 

I like the way you put the former, and agree with the latter!

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I think you are carrying too much speed.  65kt over the fence and 60kt over the pavement is too fast IMO.  at 15° flaps I'm usually about 5-10kt slower in each position.  Try approaching at 60kt and crossing the threshold at 55kt, and I bet the problem goes away.  It's a common problem to "carry an extra knot or two for the wife, three more for the dog, and one more just to be safe" and end up way too fast.  Trust the machine, it won't start to get into serious sink above 50kt or so at 15°, and that still leaves plenty for pitch authority at the bottom.  And the CT series has outstanding power to weight; if you see the sink become too high you can add a little power and the decent will be slowed or arrested almost instantly. 

Your touchdown should be around 42-45kt at 15° flaps; if you cross the pavement at 60kt I don't know how you can touch down at that speed without eating half the runway in ground effect.  at 30° flaps in no wind I often make approaches at 48kt and as low as 46kt and don't have any issues with the flare.  These are solo numbers and you might need to add a knot or three to these numbers in a CTLS.

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1 hour ago, FastEddieB said:

Admittedly, there are those who hold that a CT is a strange beast that requires special techniques in the landing.

I don't think the CT "requires special techniques", but it definitely requires understanding the quirks of the airplane and where it might bite you, like any other airplane.

*  The CT is slippery/low drag with smooth composite wings and no rivets or struts, so it tends to pick up speed quickly and shed it more slowly.

*  The CT (SW at least) has a narrow gear track and you have to be gentle with directional changes on the ground or it will feel "squirrelly".

*  Light pitch forces make it easy to over-control in the flare and lead to ballooning -- another reason proper speed control is essential.

* The light weight and low inertia means if you land at appropriate speed you have to round out lower than many other airplanes; failure in this often means a firmer than desired touchdown.

*  It is a rudder airplane, you have to use your feet!  Knowing correct alignment on landing can be a challenge for beginners because you can't see the cowl/spinner

Now the real upside:  If you master all of these quirks the CT will make you a better pilot.  Fly a CT for a month then go fly a 172, it will seem like "easy mode".  :D

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Andy,

Of course. Stipulated that all planes have their own quirks and idiosyncrasies - that’s the reason for transition training and required checkouts for an unfamiliar aircraft. And it’s good you pointed out several characteristics that could catch a new CT pilot unawares.

But I guess my point was that a CT was not fundamentally different from other planes, at least not to the point that the fundamentals of landing a plane had to be reinvented for it. That’s all.

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29 minutes ago, FastEddieB said:

Andy,

Of course. Stipulated that all planes have their own quirks and idiosyncrasies - that’s the reason for transition training and required checkouts for an unfamiliar aircraft. And it’s good you pointed out several characteristics that could catch a new CT pilot unawares.

But I guess my point was that a CT was not fundamentally different from other planes, at least not to the point that the fundamentals of landing a plane had to be reinvented for it. That’s all.

I don't want you to think I was disagreeing, just pointing out the quirks of the CT that pilots need to keep in mind.

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2 hours ago, FlyingMonkey said:

I think you are carrying too much speed.  65kt over the fence and 60kt over the pavement is too fast IMO. 

Exactly my thoughts, especially when solo / lighter on fuel.  Once I developed slower approaches and worked towards shorter runways and landing roll outs, everything improved.  Seems the flair spends the energy better and plane settles.  And don't discount gusty conditions, if it's calm or steady winds I usually have amazing landings, if wind is variable and any gusting - we'll you take what you get.

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I have had this bouncing problem for 200 hours in 172, CT, Diamond.

The problem is corrected when I realized that I was rushing to touch down.

When I'm over the numbers at 55kt 15 flaps in my CTSW, the plane still wants to fly, if I let the plane touch down, it will bounce.

So, I learned to wait and let the plane continue to fly on the runway while slowly raising the nose a little bit at a time to bleed out the energy. Eventually the plane will touch down around 35kts, it will be a smooth landing every time. 

Give it a try, this might help!

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3 hours ago, FlyingMonkey said:

I think you are carrying too much speed.  65kt over the fence and 60kt over the pavement is too fast IMO.  at 15° flaps I'm usually about 5-10kt slower in each position.  Try approaching at 60kt and crossing the threshold at 55kt, and I bet the problem goes away.  It's a common problem to "carry an extra knot or two for the wife, three more for the dog, and one more just to be safe" and end up way too fast.  Trust the machine, it won't start to get into serious sink above 50kt or so at 15°, and that still leaves plenty for pitch authority at the bottom.  And the CT series has outstanding power to weight; if you see the sink become too high you can add a little power and the decent will be slowed or arrested almost instantly. 

Your touchdown should be around 42-45kt at 15° flaps; if you cross the pavement at 60kt I don't know how you can touch down at that speed without eating half the runway in ground effect.  at 30° flaps in no wind I often make approaches at 48kt and as low as 46kt and don't have any issues with the flare.  These are solo numbers and you might need to add a knot or three to these numbers in a CTLS.

Crossing the pavement at 60kt and then touch down before the first of 5 turn offs on a 5000k ft runway. I'd imagine when I was touching down I was 55kt. I'll work on getting this down to 42-45kt. I assume that small amount is a TON of excess energy. 

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I had my BFR recently.  We spent a bunch of time in the plane and his one criticism was my lack of standard pattern technique. I tended to create a B17ish pattern and my CFI pointed out that if the engine quit I’d be one of those guys who set it in a mile from the airport.

Now, I get closer to the airport in downwind and base and focus on a stable descent speed.  I also cut a lot more RPMs than I used to have.  And I added more effort in my trimming. In sum, I am getting into a nice pattern routine and coupled with the landing technique outlined by Okent’s comments above, my landings have been much improved. 
in sum, in addition to all the other points... work on a more stable pattern removing variability and stress...

 

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16 hours ago, AGLyme said:

I had my BFR recently.  We spent a bunch of time in the plane and his one criticism was my lack of standard pattern technique. I tended to create a B17ish pattern and my CFI pointed out that if the engine quit I’d be one of those guys who set it in a mile from the airport.

Now, I get closer to the airport in downwind and base and focus on a stable descent speed.  I also cut a lot more RPMs than I used to have.  And I added more effort in my trimming. In sum, I am getting into a nice pattern routine and coupled with the landing technique outlined by Okent’s comments above, my landings have been much improved. 
in sum, in addition to all the other points... work on a more stable pattern removing variability and stress...

 

Good point.  The light weight and low inertiaof LSAs kind of demands tight patterns for safety.  At my home airport there is a ~3500ft crossing runway to the main runway; when I'm on downwind I pass right over the end of that runway.  I often call out "turning short final" because my pattern is tight enough that when I roll out on final I'm almost at the approach lights. 

The downside is you often have to extend your downwind to make room for the 172 "heavies" on their one mile finals.  :D

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