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Bounced landings - aft CG ?


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1 hour ago, ChrisV said:

Not sure what you mean by this.  i assume slowly decelerate to the desired speed?  Or do you mean attempt several landings, increasing the speed each time.

I do a high, slow, gradual flare which usually bleeds the speed quite well.

I meant both, actually. 

Like @Hank said, shoot for a slightly lower speed on a series of landings to build up your sight picture and comfort level.

Early on final, I think it's easier to shoot for a speed 5-10 knots higher than your target, and then let it gradually come down to that target rather than trying to hit that airspeed from the beginning.

Edited by jaylw314
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The term "bounce" with regard to the Mooney airframe is a bit of a misnomer.  I can assure that a Mooney will only "bounce" if it is still flying.  You are likely 1) touching down faster than you need and 2) not delivering the plane to the runway at the appropriate attitude and rate of descent.  My recommendation is to find a long runway and practice power off, mains only landings (I do T&Gs but I won't recommend that here for fear of being flamed).  You could start by practicing "flying the nose" on a big wide runway.  This is to say taxiing fast enough to raise the nose wheel but not lift off.  Given your time in type, probably a good idea to have an instructor on board. Also, 65KIAS is plenty across the threshold even at gross.  As an aside you can see how a 200hp Mooney climbs with full flaps from 1:27 to 1:43.

 

 

Edited by Shadrach
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2 hours ago, ChrisV said:

Not sure what you mean by this.  i assume slowly decelerate to the desired speed?  Or do you mean attempt several landings, increasing the speed each time.

I do a high, slow, gradual flare which usually bleeds the speed quite well.

@Bob - S50 described this above...

Expect to take several trips around the pattern, experimenting with speed...

Starting from the top of the window, moving to the bottom of the window...

Did your CFI explain the sight picture and holding the nose off? (Please answer this question, more on that later)

 

The usable speed window is about 10mias tall...

The window stays 10mias tall, but moves with weight, configuration, and X-wind component...

  • Above the top of the window... you run out of runway, or force the nose down on the runway...
  • At the top of the speed window... long landings and bounces are the two options...
  • Get goofy, you will be counting bounces... the third bounce is more than likely the prop strike...
  • At the bottom of the window... short predictable landings are assured...
  • Below the bottom of the window... Early arrival, and hard landings happen...

 

Flying a Mooney can be incredibly predictable...  unless something gets broken, worn beyond limits, or out of adjustment...

The effects you are describing are typical of....

  • flying while being distracted...
  • approaching the landing at too high of a speed, by only a few knots...
  • Cutting the throttle pretty far before getting to the runway... 
  • not holding the nose off, while allowing the speed to dissipate...
  • Don’t hold the nose off, while 5’ agl... this also allows for an incredibly hard landing... :)
  • Not knowing what speed and altitude you actually are really at during the landing... or..
  • Not knowing what your actual gross weight is...
  • Rusting up... new pilot, or new 2U plane, rust can occur over a couple of days...  old pilot, old plane, rust typically occurs over a week... flying once per week, just doesn’t maintain that smooth landing perfection very well...

 

It is Ok to hire a Mooney CFI to review and fly for an hour... it is worth it.

It really helps to fly some slow flight, in a straight line, at altitude, in the landing configuration, with the stall horn going on and off... (not steady on, that would be showing inability to stay in tune during the flight...)

know what the speed of the day is when the stall warning is sounding...

Then take that experience to the runway...

repeat on the following day... if you are magically in tune with the plane making soft landings... you have successfully knocked off the less than fictional rust...

Tell us about your multitasking skills... how many things are you accomplishing at one time... are your radio calls occurring on time as expected? Did your Gumps check get executed completely the first time?

 

Flying a plane, you get to learn what it is like to be human.   You get to see some pilot’s Missed radio calls, skipped parts of the Gumps checks, bouncing landings... these are the things you will see with a fast plane, and a not so used to it pilot... or a rusty pilot...

I’m glad we can speak openly about these human challenges... back in the day.... we would not have the opportunity to discuss such detail...

PP thoughts only, want to have some fun... try to learn to fly in a Long Body....  :)  the heavier the plane the more challenging the speed control...

Best regards,

-a-

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2 hours ago, DXB said:

You can bounce either because you have too much energy and/or because you flare too high and thus hit too hard.  Your statement above clearly confirms the former to be true.  Therefore it's just a speed control issue - probably you simply weren't as precise on speed control because of the distracting concern of your wife and child on board. Never ever push the nose forward in these planes.  And if you bounce, keep the back pressure in no matter what.  Good decision to go around.  Next time go around earlier if the situation looks the same.  Really fine tune your airspeed on approach, and plane will land itself without any worry about the runway end looming in your site picture. Also 2700ft is actually a bit short, particularly with tall trees at both ends.  A bit shallower approach than you're used to can make airspeed control easier, but the trees may prevent it.  With that runway length and tree configuration, you may never get comfortable landing on a gusty day.  Conditions that might shear to a tailwind on final will be of particular concern, and you will have some go arounds despite doing everything right.

I agree with this comment: the plane will bounce if you drop it in from too high a flare, and in fact, this is a bad place to be: Airborn with insufficient speed to fly. BTDT.... more than once.

youre sitting very low in the mooney as compared with other types.  Get a good look at the sight picture, stay outside the airplane, practice landing with the seat cranked up and down.  You should be able to feel the plane enter the  ground effect: it almost accelerates a little. My technique is to continuously roll in nose up trim while rolling out the throttle. Finally, remember to follow through with the yoke: just like shooting trap, finish with the yoke in your labp, and you will find your landings improved immensely.

 

finally: Go up to altitude and experiment with actual stalling speed in landing configuration at a few weights. I have recorded where the stall warning goes off and where the buffet begins. In my case, with TKS, it’s actually right at the book values. For a short field, you really shouldn’t be more than 1.2  x Vso when crossing the threshold. That’s still giving you a lot of airspeed buffer before the stall.

 

-dan

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2 hours ago, DXB said:

You can bounce either because you have too much energy and/or because you flare too high and thus hit too hard.  Your statement above clearly confirms the former to be true.  Therefore it's just a speed control issue - probably you simply weren't as precise on speed control because of the distracting concern of your wife and child on board. Never ever push the nose forward in these planes.  And if you bounce, keep the back pressure in no matter what.  Good decision to go around.  Next time go around earlier if the situation looks the same.  Really fine tune your airspeed on approach, and plane will land itself without any worry about the runway end looming in your site picture. Also 2700ft is actually a bit short, particularly with tall trees at both ends.  A bit shallower approach than you're used to can make airspeed control easier, but the trees may prevent it.  With that runway length and tree configuration, you may never get comfortable landing on a gusty day.  Conditions that might shear to a tailwind on final will be of particular concern, and you will have some go arounds despite doing everything right.

I agree with this comment: the plane will bounce if you drop it in from too high a flare, and in fact, this is a bad place to be: Airborn with insufficient speed to fly. BTDT.... more than once.

youre sitting very low in the mooney as compared with other types.  Get a good look at the sight picture, stay outside the airplane, practice landing with the seat cranked up and down.  You should be able to feel the plane enter the  ground effect: it almost accelerates a little. My technique is to continuously roll in nose up trim while rolling out the throttle. Finally, remember to follow through with the yoke: just like shooting trap, finish with the yoke in your labp, and you will find your landings improved immensely.

 

finally: Go up to altitude and experiment with actual stalling speed in landing configuration at a few weights. I have recorded where the stall warning goes off and where the buffet begins. In my case, with TKS, it’s actually right at the book values. For a short field, you really shouldn’t be more than 1.2  x Vso when crossing the threshold. That’s still giving you a lot of airspeed buffer before the stall.

 

Mastering this plane and getting a series of greasers will be very satisfying.

-dan

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3 minutes ago, Shadrach said:

I will say again Mooneys don’t really bounce below flying speed.  

If you get a Mooney to bounce below stall speed it will likely not be flyable afterwards. 

Ross,

I don't want to quibble over the aerodynamics  - but the cause and cure of a bounce from too high a flare are different from those associated with forcing a too-fast airplane to land before it's ready.  Too high a flare drops the nose to gain airspeed above landing speed to produce a bounce?  Springy gear launches the plane back into the air?  maybe a combination of the two?  Whatever it is, mastering the sight picture for the flare, continuously raising the nose, and managing airspeed all play an important role in good landings.

-dan

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1)

If it stops flying at 5’ agl....

It is partially flying still, the root of the wing stalls first, so the acceleration towards the ground is quite strong...

If/when you experience this.... full throttle may slow the effect... you just run out of time to get the power developing...

Gear doors get checked to see how compressed things got during the crash landing...

 

2) 

If the Mooney gets forced onto the pavement...  before it is ready to do so on its own....

This guarantees hitting nose first, then mains.... often by just inches...

Initiating the Porpoise...

The Porpoise is a divergent experience.... each one getting worse and stronger...

 

3)

The purpose of the porpoise discussion.... 

This is AKA the nose gear compression test...

And prop tip impact strength test...

Both of these result in the tear down experience...

 

To avoid the porpoise... expeditiously initiate the Go-around...  See earlier discussion on the bounce and go...

 

4)

Experienced and Current pilots avoid the porpoise... by avoiding the off speed landings... if the bounce occurs, it is a sign of not being current...  

few people bounce landings enough to practice saving the landing after the bounce... so the proper response is to just go around... you prove to yourself when things are not working in the moment... it’s not time to invent something new.... :)

The dynamics of controlling the plane after the bounce makes for interesting physics discussions... in the regime where the control surfaces are getting really week...

5)

For fun... go to a Mooney fly-in.   See all the variations that occur when a dozen Mooneys come in... getting there early....

  • Maximizes the number of landings you can witness
  • minimizes the number of witnesses around to see my bounce and go technique....
  • My favorite Mooney CFII complimented my decision making skill... (I showed up late, many MSers have witnessed)

PP shared experiences only, not a CFI...

Best regards,

-a-

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2 hours ago, exM20K said:

Ross,

I don't want to quibble over the aerodynamics  - but the cause and cure of a bounce from too high a flare are different from those associated with forcing a too-fast airplane to land before it's ready.  Too high a flare drops the nose to gain airspeed above landing speed to produce a bounce?  Springy gear launches the plane back into the air?  maybe a combination of the two?  Whatever it is, mastering the sight picture for the flare, continuously raising the nose, and managing airspeed all play an important role in good landings.

-dan

Dan,

If you think about it there is really no nose drop unless you stall in the flare at 30’ AGL in which case you have bigger problems. You are correct in your aerodynamic analysis of a stall but you’re magnifying the rate the nose drop happens in an unrealistic way. If you’ve ever done or seen a full stall, three point landing in a taildragger you will witness an exaggerated version of what I’m talking about. The plane will just pancake in if you maintain nose up elevator.  When the nose falls in a power off stall  The first 10 to 15 feet or more of drop are more of a flat mush.  It doesn’t feel or look that way in the air because you have no point of reference.  Any pronounced nose drop happens after you’ve lost way more altitude than what would be considered in the realm of normal for a flare.

The only time I get a bounce when I’m on speed is on a gusty day when A gust of wind foils my touchdown. Mooney gear are not that springy.  I’ve been picked up I’ve been picked up and slammed back down when the bottom fell out of the gust. The plane stays planted. 

In the video that I linked (which I also made) the aircraft is fully stalled on the runway in ground effect as it touches down. While you can’t see the elevator, I know that it was nearly full aft to hold the nose off. The takeoff following the touch and go actually required me to relax back pressure as I added in throttle to maintain the proper lift off attitude. 

Proper speed and attitude (read pitch control) are the keys to avoiding a bounce. Keep the nose up until it stops flying and it’s only going to touch down once, how softly depends on execution and luck.  Sometimes mother nature will throw in a strong gust to thoroughly screw up the best laid plans!

Edited by Shadrach
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5 hours ago, ChrisV said:

We took off, head north and my wife is feeling air sick and the baby won't keep his headset on and earmuffs aren't enough protection IMO.

I haven't read with detail all of the others comments - but I would submit it was the above statement that was the first link in the chain to your "not so perfect" landings. 

As hard as it is in these situations the passengers are a concern to get on the ground but not the main concern,

The main concern is to force yourself to think about your duties and even though they are uncomfortable they will be fine. BTW - I make sure each passenger position has two barf bags courtesy of the big boys..... 

You experienced "get thereitis  in an attempt to get your passengers on the ground in the most expedient way - lucky it was only three sub par landings and not something worse. 

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@ChrisV, I should also point out that I have the advantage of a wife who is very accustomed to hearing my exclamation of "ARRRRGHH!!!!" every time I make anything less than a perfect landing, so by now I don't have to worry about her getting nervous :)  Your wife has only had 3, but she's well on her way

Edited by jaylw314
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2 hours ago, gsxrpilot said:

As everyone else has said, this isn't a CG issue.

It is a distraction, experience, issue.

A good CFI is great, but can also mask issues by fixing them before you notice them. If I were you, I'd go do a bunch of landings by yourself. Solo, with plenty of gas, you'll have options of finding a longer runway. Or even start with a longer runway and get super comfortable. Then go back to your home field and do a bunch on the short runway.

There's a reason all training involves solo flight. Go get some practice on your own.

+1 practice practice practice, nice thing about using a longer runway is you can artificially make them shorter by using land marks that match your home field.  As you work towards slowing your final approach speeds please keep in mind your pattern turns and don't lose sight of your airspeed and wing loading (AOA) in your turns as this is so important and sadly a frequent cause of tragic accidents by even very experienced pilots. 

There aren't many things we humans can do where practicing can also be super fun. So go have fun

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Want to use a tech tool to help you know what you did earlier in the flight...?

There is an app for that...

When combined with a WAAS source,  the app gets really good at analyzing and recording landing info...

Look for CloudAhoy... an excellent tool for learning/tuning various parts of flying...

Also does a good job of collecting engine health data... through T/O roll and climb rate...

https://www.cloudahoy.com/

Best regards,

-a-

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So much information!   I am a CFI.

First and best recommendation is get another instructor - one that owns or regularly flys Mooneys, Bonanza's or other heavy low wingers - regularly - not one that has mostly Cessna time!  The one you have has not transferred any usable piloting skills to you.  Landing a Mooney nose wheel first ever is your first clue that you need another.  Whatever you were doing was considered good enough.  There is only consistent good and better in Mooney training.

2. Your problem is approach speed (maybe), and mostly roundout timing(power off or you will discover what float is) and consistent nose position movement skill - a smooth raising of the nose as you sink into the ground effect cushion to an attitude with the nose cowling top at near the far end of the runway - LOOK at the far end - cowl near it! - no higher (with full flaps) - (the nose position is higher with less flaps and less weight - so use full flaps always for consistency and for lowest touchdown energy).  Don't keep pulling up the nose like a Cessna or not pulling up like a Cessna and landing on the nose first.  Goal is to have the nose attitude up and stable at a about a foot or so off ground, and hear the stall warning horn as it rolls onto the mains. HOLD the nose in that attitude and it will gently drop onto the runway.

3. Weight, wind, and gust determines speed on final.  Know the numbers you are shooting for and have the wind and gust factor added in right down to round out (Wyoming has nothing but wind).  Get help on developing a consistent smooth skill set.  And don't worry about CG.  Practice smoothly putting the nose up without ballooning to where it belongs during roundout with the correct approach airspeed and the Mooney flies itself on at lowest energy almost every time and  you will learn a new joy.

 

Edited by Cayman44
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6 hours ago, irishpilot said:

Mooney's are pitch sensitive if you are even a few knots fast when you enter ground effect. My two recommends are, keep up on trimming through the pattern and shoot for +-0 knot deviation on short final. With that mentality, you'll notice a tighter shot group of landings. Mooney's are slippery, hence why they are awesome XC machines. Enjoy your plane!

Bob Kromer talked about this.  For every 1 knot over touchdown speed, add 100 feet to your landing distance.  So 10 knots fast on touchdown?  You better have extra runway or really good braking action.

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5 hours ago, Shadrach said:

I will say again Mooneys don’t really bounce below flying speed.  

If you get a Mooney to bounce below stall speed it will likely not be flyable afterwards. 

I think this is probably true. But I suspect a harder hit from a high-ish flare with even a very modest amount of excess speed can put you back in the air briefly, whereas a slow descent would stay planted.  I used to balloon and/or bounce a lot when I started - a combination of inadequate or ill timed flare and excess airspeed. I bet most of my landings still have a little extra energy, and yet I very rarely bounce anymore.  

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43 minutes ago, DXB said:

I think this is probably true. But I suspect a harder hit from a high-ish flare with even a very modest amount of excess speed can put you back in the air briefly, whereas a slow descent would stay planted.  I used to balloon and/or bounce a lot when I started - a combination of inadequate or ill timed flare and excess airspeed. I bet most of my landings still have a little extra energy, and yet I very rarely bounce anymore.  

A Mooney can absolutely be finessed on to a runway with extra energy. Paul raises this point often. However if you screw it up, bounce city...

Edited by Shadrach
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All good points...and a lot of them so if someone mentioned this I apologize I missed it. remember the elements of a stabilized approach in addition to airspeed are VSI and on glide slope.  If your coming over the trees (close to the approach end forcing you high) at 73 to 75 then make a play for the earliest part of the runway I bet your VSI is jumping from -450 +/- to -600/700+ If your making the play for the runway with bringing the throttle back to idle passing over the trees and trying to maintain 73ish, the kinetic energy in a large VSI will translate into more than desired airspeed in the flair thus enabling more flight time.   

A wise Mooney pilot, former Vietnam A-4 driver told me early on that “a Mooney ain’t no Cessna.  Don,t flare the #!##. Fly it into the runway” 

which I translated as.... get on glide slope, stabilize VSI and capture airspeed with trim and throttle all,the way to touchdown.

Everything starts on the downwind - gear down, zero VSI, trimmed to downwind airspeed (95 kts for me) and appropriate abeam distance from the touchdown point. I actually fly hands off for a brief moment to make sure the airplane is configured how I want it.

Then base to final hitting my altitude points and airspeed numbers (with trim as flap transition) and maintaining 500ish VSI with throttle.

On final - get on glide slope, trim to airspeed, capture VSI with throttle.  

Over threshold above runway set landing attitude while throttle comes smoothly to idle

its much easier (and smoother) to bleed off airspeed with 450 VSI vice 600.

if your high on glide slope, high on VSI and on airspeed, you’re not stabilized and your going to float or force it and bounce.

 

Hope this helps...just felt like pontificating......

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52 minutes ago, anthonydesmet said:

 

A wise Mooney pilot, former Vietnam A-4 driver told me early on that “a Mooney ain’t no Cessna.  Don,t flare the #!##. Fly it into the runway” 

Anthony, I agreed with the rest of your post, but not the above sentence.  Just because the guy could "drive" an A-4 over Vietnam doesn't lend all that much credence to his statement.  It counts about as much as the fact that I "drive" an Airbus.

Done correctly, it's an effective technique with a long enough runway.  Done incorrectly, its a recipe for a porpoise down the runway or an overrun off a short field.  If the intent behind the statement was that you don't flare as much as in a Cessna, then sure, I'll get on board with that.

I've got 2200' useable landing distance at my airport and I make the turnoff after about 1100 so I don't have to taxi through potholes and gravel.  No way can you do that if you don't flare.  A friend flew his Ovation out of the same strip- the only reason he didn't flare as much as me was to keep from hitting the tail on his long body.

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7 hours ago, Shadrach said:

Dan,

If you think about it there is really no nose drop unless you stall in the flare at 30’ AGL in which case you have bigger problems. You are correct in your aerodynamic analysis of a stall but you’re magnifying the rate the nose drop happens in an unrealistic way. If you’ve ever done or seen a full stall, three point landing in a taildragger you will witness an exaggerated version of what I’m talking about. The plane will just pancake in if you maintain nose up elevator.  When the nose falls in a power off stall  The first 10 to 15 feet or more of drop are more of a flat mush.  It doesn’t feel or look that way in the air because you have no point of reference.  Any pronounced nose drop happens after you’ve lost way more altitude than what would be considered in the realm of normal for a flare.

The only time I get a bounce when I’m on speed is on a gusty day when A gust of wind foils my touchdown. Mooney gear are not that springy.  I’ve been picked up I’ve been picked up and slammed back down when the bottom fell out of the gust. The plane stays planted. 

In the video that I linked (which I also made) the aircraft is fully stalled on the runway in ground effect as it touches down. While you can’t see the elevator, I know that it was nearly full aft to hold the nose off. The takeoff following the touch and go actually required me to relax back pressure as I added in throttle to maintain the proper lift off attitude. 

Proper speed and attitude (read pitch control) are the keys to avoiding a bounce. Keep the nose up until it stops flying and it’s only going to touch down once, how softly depends on execution and luck.  Sometimes mother nature will throw in a strong gust to thoroughly screw up the best laid plans!

Excess energy and excess airspeed are not necessarily the same thing.  I had some videos of drop tests on diamond aircraft, but I can't find them. Pitty.  these things bounce!

The video below is somewhat similar - note that the plane, with the wings providing no lift at all, does bounce.  Now imagine a wing providing some lift.  Boing!

 

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Interesting thread. What causes a bounce? Try this thought experiment: Imagine a crane lifting your favorite Mooney ten feet off the ground. Then the cable breaks. How high will it bounce?

I actually witnessed something similar years ago at Mammoth Lakes California. The runway is at 7135' MSL and runs east/west. To the south is Convict Lake in a cut in the Sierra Nevada mountains. When the wind is out of the south at more than about 15 kts, it funnels down over the lake and hits the runway about midfield setting up a nasty wind shear. A friend and I were tightening the tie downs our airplanes due to a gusty south wind when we saw a M20E load up four people and taxi out, so we decided to hang around and watch. Hey, maybe the wind shear wasn't so bad and we could go home after a long day of skiing Mammoth Mountain. The Mooney climbed to about 50 feet and then started bobbing around as the wind shear hit it. If the pilot had put the nose down and landed - the gear was still down -  he'd have been OK. Unfortunately, he tried to climb out of it. The plane settled to about 10 feet before it quit. We saw it hit and heard the rumble a second later. It didn't bounce noticeably from our vantage point 500' away. It taxied back to the ramp under it's own power and everyone deplaned and walked to the FBO, presumably to attend to their underwear. We walked oven and casually inspected the plane. About 4 inches of the prop tips were bent and the landing gear doors were bent outward at 90-deg. That's a lot of main landing gear compression! 

@Shadrach is right: If it bounces, it's flying. That requires excess speed and an increase in AOA which is supplied when the pilot unconsciously pulls back when surprised by the initial ground contact.

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26 minutes ago, exM20K said:

Excess energy and excess airspeed are not necessarily the same thing.  I had some videos of drop tests on diamond aircraft, but I can't find them. Pitty.  these things bounce!

The video below is somewhat similar - note that the plane, with the wings providing no lift at all, does bounce.  Now imagine a wing providing some lift.  Boing!

 

We’re talking Mooneys Dan, not fixed gear machines with spring steel leaf springs for landing gear. The physics involved with the Mooney gear is very different. The swing arm portion of the Mooney gear is only slightly longer that the outside diameter of the tire. It has neither the travel nor the leverage. I don’t believe it will bounce like the aircraft in the video. Also, a bounce from dropping in a spring steel aircraft happens so fast that it would never produce a go around. I say this as someone who has experience dropping in spring steel aircraft. I am way more adept at landing a Mooney than a Decathlon but still trying!

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