Leadville (KLXV) in an NA Mooney?

[AndreiC]

As the OP of this thread I feel required by law to point out that the thread has drifted quite a bit  But nevertheless the new topic of rotation speed is of great interest to me. 

I take off with the plane configured with the trim and flaps set at the takeoff position. The instructor who checked me out in my M20E recommended that at around 60 MIAS I start to gently pull on the yoke, and then the plane should lift off around 70-75 MIAS. My experience has been less consistent, especially if there is a crosswind component. By pulling off the yoke at 60 MIAS the airplane does get light on all wheels, in the sense that I have quite a bit less directional control (a sideways wind gust can make the plane turn into the wind) and there is a 1-2 seconds period of time when I feel I am not really in control of what is going on.  On the other hand, if I try to let the plane accelerate more than 60 before pulling on the yoke, it feels almost as if it is trying to wheelbarrow (mains lifting before the front wheel), which is very disconcerting. So many times I will try to accelerate to 65-70 and then yank it off with a more abrupt pull, but doing this leads to a couple of seconds where the stall horn will intermittently beep, again not something I would like on a normal takeoff. So I'd like some advice on what I am doing wrong. 

[802flyer]

37 minutes ago, AndreiC said:

As the OP of this thread I feel required by law to point out that the thread has drifted quite a bit  But nevertheless the new topic of rotation speed is of great interest to me. 

I take off with the plane configured with the trim and flaps set at the takeoff position. The instructor who checked me out in my M20E recommended that at around 60 MIAS I start to gently pull on the yoke, and then the plane should lift off around 70-75 MIAS. My experience has been less consistent, especially if there is a crosswind component. By pulling off the yoke at 60 MIAS the airplane does get light on all wheels, in the sense that I have quite a bit less directional control (a sideways wind gust can make the plane turn into the wind) and there is a 1-2 seconds period of time when I feel I am not really in control of what is going on.  On the other hand, if I try to let the plane accelerate more than 60 before pulling on the yoke, it feels almost as if it is trying to wheelbarrow (mains lifting before the front wheel), which is very disconcerting. So many times I will try to accelerate to 65-70 and then yank it off with a more abrupt pull, but doing this leads to a couple of seconds where the stall horn will intermittently beep, again not something I would like on a normal takeoff. So I'd like some advice on what I am doing wrong. 

What I was taught to do in my F (and it sounds like @Shadrach does the same) is apply a steady amount of constant back pressure on the yoke as I approach rotation speed (perhaps starting around 50mph), and hold that steady input until the plane flies itself off the ground on its own. With a calibrated arm, that usually has me lifting off between 65-70, and the plane transitions in to a smooth climb out without much fuss (other than trimming down as speed builds). I think there's probably a sweet-spot amount of pressure where the plane doesn't get too light too early, but still flies off before it wheelbarrows. As the nose wheel gets light, I'll need to apply more rudder (even still on the ground) to keep centerline in a crosswind.

On a short runway, I might try to be a bit more authoritative about getting off the ground right around 65 so that I can reduce wheel drag, get the gear up, and accelerate in ground effect as soon as possible. If it's breezy with plenty of runway, I'll keep the elevator input maybe 50% lighter until around 70  at which point I "rotate" with the rest of the usual force, and then the plane flies off with plenty of control in the gusts. 

@shadrach has a lot more hours in his plane, so if he disagrees, I'd probably choose to emulate him

[Shadrach]

1 hour ago, dkkim73 said:

Hi Ross, 

Do you mean a constant pitch attitude? (more elevator early, then less later, maintain attitude to lift-off)

Or constant subjective amount of elevator, which would resulting in progressive lightening of the nosewheel and eventual rotation and lift-off? 

I suppose there is more drag at higher AOA, though @PT20J pointed out that induced drag is dominant here, and greatly reduced by ground effect (which we are in while rolling). And having the nosewheel off, or at least light, reduces wheelbarrowing. 

David

PS. Coincidentally, the scenario discussion for the Pilot Workshops newsletter (received just this morning) touches on several of these topics (Leadville, how to manage potentially not enough energy for climb-out, etc): https://pilotworkshop.com/tips/calculating-takeoff-and-landing-distance/

Hi David,

I Could not tell you the elevator/pitch position. I use back pressure on the yoke which initially is neutral but transitions to something like 5lbs aft pressure as I approach flying speed. As speed builds the nose gets light and then the mains lift off. This time of year the stall horn might chirp a bit as the mains lift off. I often reduce pitch for cruise climb right after rotation this time of year but I don’t need to stay in ground effect. I’m on the East Coast and even in the dog days of summer, the highest DAs I encounter are probably 5500 to 6000. I do raise the gear within a few seconds after lift off. Not because I’m concerned with reducing drag but because it’s easiest to raise (jbar)at low speed.

 

Edit- @802flyer precisely articulated what I do and most of us were taught.

[PT20J]

A Mooney takeoff is much more like a seaplane takeoff than any other landplane I have flown. By this I mean that it cannot always be taken off the ground smoothly by doing anything mechanically -- it must be flown off which requires a fine touch on the elevators.

Bob Kromer (former Mooney test pilot) suggests about a 5 lb pull during the takeoff roll and letting the airplane fly off when it's ready.  I find this works well on smooth runways and no significant crosswind. However, if the runway is bumpy, a combination of a bump at the wrong time and the stiff landing gear can launch it into the air before it is really ready to fly. So, if I start hitting bumps, I "fly" it with the elevators like I would to keep a seaplane on the sweet spot of the step during a take off slide.

If there is a significant crosswind, I don't want it to settle back to the ground in a crab, so I use aileron to help maintain directional control during the takeoff roll and I use the elevators to hold it on the ground a little longer than normal, but not enough to risk wheelbarrowing, and then I pull it off more abruptly so that I'm sure it will keep flying. Once airborne, I level the wings and center the ball and then retract the gear.

[Ragsf15e]

I thought the standard Mooney technique was to start the takeoff roll and just hold that “5lbs” of pull until liftoff and then adjust to desired pitch for climb.  I don’t know exactly what 5lbs is but it seems to work pretty well in my airplane (to flaps and to trim).

@PT20J beat me to it by mere seconds!  And with much more detail.

Edited July 17 by Ragsf15e

[EricJ]

The 5lb-pull will be a different amount of effort for different trim settings, so setting a consistent trim position for takeoff will make a difference there. 

I've never found takeoffs in my airplane to be very difficult or complicated, but the steady firm-ish pull is a good technique.  I don't always bother to get serious about the pull until about 50 kts or so.

[Ragsf15e]

9 minutes ago, EricJ said:

The 5lb-pull will be a different amount of effort for different trim settings, so setting a consistent trim position for takeoff will make a difference there. 

I've never found takeoffs in my airplane to be very difficult or complicated, but the steady firm-ish pull is a good technique.  I don't always bother to get serious about the pull until about 50 kts or so.

I think I’ve noticed some differences with the cg too (with trim always set at TO), but only if the cg is real far forward or back.

[Hank]

2 hours ago, AndreiC said:

As the OP of this thread I feel required by law to point out that the thread has drifted quite a bit  But nevertheless the new topic of rotation speed is of great interest to me. 

I take off with the plane configured with the trim and flaps set at the takeoff position. The instructor who checked me out in my M20E recommended that at around 60 MIAS I start to gently pull on the yoke, and then the plane should lift off around 70-75 MIAS. My experience has been less consistent, especially if there is a crosswind component. By pulling off the yoke at 60 MIAS the airplane does get light on all wheels, in the sense that I have quite a bit less directional control (a sideways wind gust can make the plane turn into the wind) and there is a 1-2 seconds period of time when I feel I am not really in control of what is going on.  On the other hand, if I try to let the plane accelerate more than 60 before pulling on the yoke, it feels almost as if it is trying to wheelbarrow (mains lifting before the front wheel), which is very disconcerting. So many times I will try to accelerate to 65-70 and then yank it off with a more abrupt pull, but doing this leads to a couple of seconds where the stall horn will intermittently beep, again not something I would like on a normal takeoff. So I'd like some advice on what I am doing wrong. 

This is what my Owners Manual says, and it's what I do. Most times, I lift off at 70 mph with Flaps Up, but when I'm heavy I'll use Takeoff Flaps at the same speed. If the wind is very gusty.and I'm a little heavy, then I may hold the plane down until 75 mph, then pop into the air.

Lift off, then relax the yoke a bit to climb attitude, verify positive rate, check course, and raise the gear. This is generally around treetop level. Accelerate to Vx is my first order of business, until I'm looking down on obstacles, then lower the nose to Vy and climb to cruise altitude, WOT / 2700.

[PeteMc]

1 hour ago, EricJ said:

effort for different trim settings

On of the first Mooney specific things I was taught for my 231 was to set the trim to the TOP of the takeoff range.  So I didn't need as much strength to pull back once the plane picked up some speed.  So it was much easier to hold back to let the plane fly off the Rwy.

 

[AndreiC]

2 minutes ago, PeteMc said:

On of the first Mooney specific things I was taught for my 231 was to set the trim to the TOP of the takeoff range.  So I didn't need as much strength to pull back once the plane picked up some speed.  So it was much easier to hold back to let the plane fly off the Rwy.

 

So you mean that the little square for the elevator trim is not aligned with the little square marked "Take-off", but rather they share an edge, with the trim indicator being above the marked square on the side?

[Hank]

2 hours ago, PeteMc said:

On of the first Mooney specific things I was taught for my 231 was to set the trim to the TOP of the takeoff range.  So I didn't need as much strength to pull back once the plane picked up some speed.  So it was much easier to hold back to let the plane fly off the Rwy.

Me, too. But when I'm heavy, I line up the marks.

2 hours ago, AndreiC said:

So you mean that the little square for the elevator trim is not aligned with the little square marked "Take-off", but rather they share an edge, with the trim indicator being above the marked square on the side?

The bottom of the elevator position mark is at the top of the mark labeled "Takeoff." Except when heavy; it helps counteract the forward CG accelerating on the runway.

[PeteMc]

2 hours ago, AndreiC said:

So you mean that the little square for the elevator trim is not aligned with the little square marked "Take-off"

Unlike the Flaps, my Trim has a range with a line at the top and bottom, not one specific point.  So I set it to the nose up end of the range.

[Hank]

Like this:

[PeteMc]

Mines Trim indicator is a little bit different.  I don't have a pic of just the pedestal, so sorry for the graininess in this blowup.  

I put a red box around where it says TAKE OFF.  My standard Trim position for Takeoff would have the indicator line (black line) at the top/nose up end of the Takeoff range.  

 

[Pinecone]

On 7/16/2024 at 3:27 PM, Shadrach said:

I have never heard or read any one advocate for yanking the aircraft off the ground at the ragged edge. I was taught to  raise the nose enough to take the weight off the nose wheel when the airplane lifted off, level to neutral pitch and accelerate.

I was taught fairly nose high, lifting off below normal lift off, then nose down to accelerate in ground effect. for soft fields.

Some of the posts in this thread could be construed as to advocating a very low speed lift off to accelerate in ground effect.

[Pinecone]

16 hours ago, AndreiC said:

So you mean that the little square for the elevator trim is not aligned with the little square marked "Take-off", but rather they share an edge, with the trim indicator being above the marked square on the side?

I have two lines marking a range and the moving part is about the same size.  I put the middle of the indicator at the upper line marking the TO range.

[AndreiC]

Wow, very interesting. I'll try this next time. My indicator looks like @Hank's above, and I always aligned the white elevator position indicator to be covering exactly the the left side of the white part of the "Take Off" writing.

[dkkim73]

21 hours ago, AndreiC said:

As the OP of this thread I feel required by law to point out that the thread has drifted quite a bit  But nevertheless the new topic of rotation speed is of great interest to me. 

I take off with the plane configured with the trim and flaps set at the takeoff position. The instructor who checked me out in my M20E recommended that at around 60 MIAS I start to gently pull on the yoke, and then the plane should lift off around 70-75 MIAS. My experience has been less consistent, especially if there is a crosswind component. By pulling off the yoke at 60 MIAS the airplane does get light on all wheels, in the sense that I have quite a bit less directional control (a sideways wind gust can make the plane turn into the wind) and there is a 1-2 seconds period of time when I feel I am not really in control of what is going on.  On the other hand, if I try to let the plane accelerate more than 60 before pulling on the yoke, it feels almost as if it is trying to wheelbarrow (mains lifting before the front wheel), which is very disconcerting. 

If the thread police weren't so lenient, they would've put me up against the wall a few months ago

Your description sounds familiar, and it's great to hear the responses. Compared to other planes I've flown (lighter wing-loadings I would guess) there seems to be more of an "interregnum" where you're not really flying, but you're too fast to be taxiing on the nosewheel.  For cross winds and weather-vaning, I have been concentrating more on maintaining intermediate aileron positions and "working the controls" more like a taildragger. But I still don't have the sense of control, lifting off and touching down on one wheel, etc., that I would like. OTOH it seems to take more of a crosswind to make it matter. 

 

[Hank]

3 hours ago, AndreiC said:

Wow, very interesting. I'll try this next time. My indicator looks like @Hank's above, and I always aligned the white elevator position indicator to be covering exactly the the left side of the white part of the "Take Off" writing.

Those settings (Trim on left, Flaps on right) are my normal takeoff settings. This day I was solo. 

When loaded up, I align both the Trim and Flap indicators with the Takeoff marks.

[PeteMc]

On 7/17/2024 at 10:38 AM, AndreiC said:

As the OP of this thread I feel required by law to point out that the thread has drifted quite a bit  But nevertheless the new topic of rotation speed is of great interest to me. 

Very true.  I'm guessing this software doesn't allow for pruning of topics.  Back in the ol' AVSIG days if a topic changed, the Admins could spit it off and give it a more appropriate new title. 

 

[Bartman]

On 7/17/2024 at 3:07 PM, PT20J said:

A Mooney takeoff is much more like a seaplane takeoff than any other landplane I have flown. By this I mean that it cannot always be taken off the ground smoothly by doing anything mechanically -- it must be flown off which requires a fine touch on the elevators.

Bob Kromer (former Mooney test pilot) suggests about a 5 lb pull during the takeoff roll and letting the airplane fly off when it's ready.  I find this works well on smooth runways and no significant crosswind. However, if the runway is bumpy, a combination of a bump at the wrong time and the stiff landing gear can launch it into the air before it is really ready to fly. So, if I start hitting bumps, I "fly" it with the elevators like I would to keep a seaplane on the sweet spot of the step during a take off slide.

If there is a significant crosswind, I don't want it to settle back to the ground in a crab, so I use aileron to help maintain directional control during the takeoff roll and I use the elevators to hold it on the ground a little longer than normal, but not enough to risk wheelbarrowing, and then I pull it off more abruptly so that I'm sure it will keep flying. Once airborne, I level the wings and center the ball and then retract the gear.

Excellent point !

My home-ish airport has bumps about 800 ft or so down the runway and since it’s over 5,000 ft long I usually accelerate slowly, and slowly then add full power. Otherwise you get launched into the air and find yourself on the back side of the power curve on takeoff. Not fun. If you land on the numbers you are good, otherwise might as well add a little power and let her float on past that area. 

They worked on it and it’s better than it was, but don’t expect to take off and transition smoothly with very low ceilings. I did that once….