Rotate (F model)

[chrixxer]

My E used to more or less leap off the runway around 65mph and climbed like a homesick angel. I've only taken off in the F twice, and both times was heavy: KMPI (uphill, rwy 26) with fuel at tabs, two big guys up front, and 49 years of logbooks, spare oil, etc, in the back; KPRB with full fuel and the same cargo / rear seat sitch.

Both times it felt like I really had to muscle her off the ground. Trim was set to takeoff, both times. Owner's manual says to apply back pressure between 65-75 mph, which is what I was doing. Am I doing anything wrong? Or is this just a function of the longer fuselage and heavier weight?

[kpaul]

My F has never leapt off the runway was others have described.  If it is just me or one other up front, I add a little more nose up trim.  

[Brian Scranton]

I have my trim set just above the "take off" setting...so where it's half in and half out of the "take off" mark. 

I rotate at 70mph. Push the nose over a bit to accelerate to 90mph, then get positive rate, gear up. Trim for 100mph climb.

I'm at 6000' feet and DA is often in the 7 to 10K range. But I do this at sea level too. 

 

[TTaylor]

I find that the F does not "leap" off the ground.  You have to rotate and get it to unstick, establish a positive rate of climb, raise the gear, and accelerate a little to get it climbing. I do not expect rapid climbs when heavily loaded.  

On the plus side it is more pitch stable and for me is easier to stabilize for landing than my old C.

[Marauder]

Little more nose up trim.

 

 

Sent from my iPhone using Tapatalk Pro

 

[carusoam]

Consider taking some measurements with a WAAS source and an app...

I use CloudAhoy and a portable WAAS ADSB device  for this.

Now is the time to determine that the engine is producing the proper power.

There are a few things like wear that can slowly rob the engine of power.  Corrosion can really wear a cam down...

 

• measure the take-off run.  With or without a tech device... (tech device makes it super easy)
• take note of the sustained climb rate...

Compare these two carefully determined pieces of data to the book values.  Weight, Alt, and temp are important.

Compare these two pieces of data to the values for the M20E.

Compare the power to weight ratio of both ships, at their lightest and at MGTW.

People in retirement phase of life, enjoy the M20E for a reason.  It’s not just economics...

 

Take the time to actually measure what you have.  This will shorten the amount of time that it takes to get real familiar with the new ride.  It will also remove some of the fear of wondering if things are working properly.  

If something is amiss, it is better to know it now. It won’t get better with time. It won’t fix itself...

Don’t skip the opportunity to know...

Nobody knows this better than Chrixxer... 

PP thoughts only, not a mechanic.

Best regards,

-a-

 

[Dream to fly]

1 hour ago, chrixxer said:

My E used to more or less leap off the runway around 65mph and climbed like a homesick angel. I've only taken off in the F twice, and both times was heavy: KMPI (uphill, rwy 26) with fuel at tabs, two big guys up front, and 49 years of logbooks, spare oil, etc, in the back; KPRB with full fuel and the same cargo / rear seat sitch.

Both times it felt like I really had to muscle her off the ground. Trim was set to takeoff, both times. Owner's manual says to apply back pressure between 65-75 mph, which is what I was doing. Am I doing anything wrong? Or is this just a function of the longer fuselage and heavier weight?

You might just want to verify if the trim indicators are actually correct.  My indicators were so far off that I had the same issue.  Turns out after I had re rigged the plane the plane was a lot less of a mule to get to climb or descend.

[3914N]

My G is exactly the same way.  I find as I accelerate into the white arc, the airplane begins to "dance" and I apply a fairly significant amount of back pressure to pull it off the runway.  After I break ground, I need to relax the back pressure to avoid overrotation.

I find that the rotation is easier with back seat pax, but the overrotation after liftoff is worse.  I suppose that is consistent with a more aft CG.

[Browncbr1]

You also have a top prop on your new to you F.   I have one on my F as well. They aren’t known for being impressive on roll or climb, but maybe a little better on cruise and noise.  

[Yetti]

half flaps will pop them off the runway.  No flaps and you have to work them off.

[MikeOH]

1 minute ago, Yetti said:

half flaps will pop them off the runway.  No flaps and you have to work them off.

Is that synonymous with the "Take-Off" setting?

[Yetti]

Yes.  Some older Mooneys with hydraulic flaps are 1 pump for this and 3 for that.

[M20F-1968]

The trim indictor probably is not adjusted for the true empennage setting.  I would start by checking with a travel board (especially since it is a new to you plane), then set the trim indicator where you want it for T/O indication (I used a thin line, not the 1/4 gray T/O zone as you want to get the most repeatable setting possible so the plane acts similarly each time).  Then decide based on that position whether you need more trim up or down based on how it flies.  You can use the travel board setting and how it flies at that setting to set your trim indicator.

John Breda

[gsxrpilot]

First make sure it's rigged right. Lot's of vintage Mooneys have been incorrectly rigged over the years of questionable maintenance. This will require the proper travel boards and someone who knows how to use them. 

Now that you're rigged right, use trim as required to get the plane to lift off easily. Note the position of the trim gauge. That is now your new Takeoff trim position.

[chrixxer]

Lasar checked and adjusted the rigging recently, but it can't hurt to have it checked. Who in SoCal is a good shop for that?

Electric flaps, FWIW, and yes, I was taking off with them in TO position.

Comparing it in its current configuration (scimitar prop) to book values doesn't seem like it would be all that useful. The engine has been well looked after, oil analysis going back >10 years, top end rebuild within the last ~250 hours. Seems to accelerate fine (though checking with CloudAhoy or another tool also can't hurt - if only to more accurately predict T/O roll, etc., if not to compare with book #s ... Would ForeFlight's track log provide enough insight for that? It's getting a 10m-accurate signal from the FreeFlight ADS-B system, but I also have a Stratus I can use...)

[Cyril Gibb]

Note that a Scimitar prop on an F (IO360A1A) has 3% INCREASED takeoff distances than the original prop, according to my STC documentation.

Don’t know about cruise differences since I bought it with the new prop. 

[chrixxer]

Just now, Cyril Gibb said:

Note that a Scimitar prop on an F (IO360A1A) has 3% INCREASED takeoff distances than the original prop, according to my STC documentation.

Don’t know about cruise differences since I bought it with the new prop. 

Yeah, I'm aware. I haven't played with her much in cruise yet. I want to check the FS-450 calibration, figure out leaning with the EDM-700, etc., in addition to running the numbers to calculate true airspeed. According to the rough calculations in the GNS430W, I was getting about 145 ktas at 7500-8500', WOT, 2500 rpm (MP was below 24", even with ram air on, so no issues with the new placarded range for the scimitar). I will say she's very pleasantly quiet in cruise. Not sure how much of that is the prop, vs. the sound insulation Ron installed, vs. the A20 headset I picked up on Thursday. Whichever, it's a very nice change from my E (which, even with Aviation Xs, sounded like I was flying behind an angry, poorly maintained lawn mower).

[carusoam]

Continue checking all the details for yourself... prove that they are meaningful...  make it work because you are worth it.

One of the nice things about the cloudahoy app... It has a graphic result... if the data shows a handful of straight points near the runway you were using... that would be the non-WAAS IPad solution.  Not very good when you are trying to measure exactly 801’ ...  10m accuracy is one thing, but if it only measures three points on the runway, the accuracy of the three points won’t matter much.

If it shows every curve you took while you taxi near the centerline... that would be a WAAS result.

 

You have a modern machine that is incredibly well documented.  Unfortunately it may take some effort to acquire all the data...

Starting with the STC data that Cyril just pointed out.

Summer is coming.  Hot and heavy are a part of Mooney life.

You want to have a reliable method of calculating WnB, T/O run for the DA and conditions that you have.

Don’t fall for the old Mooneys have no data in the owners manual trick...

You are still going to add proper padding for errors.  But the padding has to be added to the tightest calculations you can make.

 

On the topic of using T/O flaps and empty back seats...  the flaps generate a fare amount of nose down force...  trimming to the top of the T/O range is ‘normal’ for this... but not really enough to do the job...  your arms are going to be required.

Not sure why the trim zone is so tight.  Somewhere, somebody, got it wrong...  too much power, with too much trim, leads to a surprise nose High attitude, near the ground...

Study the POH that you have.  See if the newest version of your POH has more data.  Get the STC for the prop.  It is like a mini POH.  It has real science and math you can use.

With all that data...

What you will find is things like a 10% change in power can add 50% to the T/O run... then you add the effects of DA.

 

It would be really cool if off Airport landing experience was limited. Like one and done...  

 

Hope that is motivating...

PP thoughts only, not a CFI...

Best regards,

-a-

 

 

[steingar]

The F has the same engine as the E, but it has a larger fuselage and is therefore heavier.  Given the same power and more weight, it makes some small sense that the new aircraft wouldn't take off with the same alacrity as the old one.

[Stephen]

On 4/15/2018 at 11:14 AM, Brian Scranton said:

I have my trim set just above the "take off" setting...so where it's half in and half out of the "take off" mark. 

 

 

Found exactly the same thing in my "F" & I use Scranton's technique .... half in, half out. 

Edited April 17, 2018 by Stephen

[chrixxer]

18 hours ago, carusoam said:

Continue checking all the details for yourself... prove that they are meaningful...  make it work because you are worth it.

One of the nice things about the cloudahoy app... It has a graphic result... if the data shows a handful of straight points near the runway you were using... that would be the non-WAAS IPad solution.  Not very good when you are trying to measure exactly 801’ ...  10m accuracy is one thing, but if it only measures three points on the runway, the accuracy of the three points won’t matter much.

If it shows every curve you took while you taxi near the centerline... that would be a WAAS result.

 

You have a modern machine that is incredibly well documented.  Unfortunately it may take some effort to acquire all the data...

Starting with the STC data that Cyril just pointed out.

Summer is coming.  Hot and heavy are a part of Mooney life.

You want to have a reliable method of calculating WnB, T/O run for the DA and conditions that you have.

Don’t fall for the old Mooneys have no data in the owners manual trick...

You are still going to add proper padding for errors.  But the padding has to be added to the tightest calculations you can make.

 

On the topic of using T/O flaps and empty back seats...  the flaps generate a fare amount of nose down force...  trimming to the top of the T/O range is ‘normal’ for this... but not really enough to do the job...  your arms are going to be required.

Not sure why the trim zone is so tight.  Somewhere, somebody, got it wrong...  too much power, with too much trim, leads to a surprise nose High attitude, near the ground...

Study the POH that you have.  See if the newest version of your POH has more data.  Get the STC for the prop.  It is like a mini POH.  It has real science and math you can use.

With all that data...

What you will find is things like a 10% change in power can add 50% to the T/O run... then you add the effects of DA.

 

It would be really cool if off Airport landing experience was limited. Like one and done...  

 

Hope that is motivating...

PP thoughts only, not a CFI...

Best regards,

-a-

 

 

The iPad is connected to a FreeFlight (WAAS) or Stratus 2S (WAAS) GPS source.

I'm reading everything I can find on her, and will be limiting my operations to big/wide/easy airports while I get used to her.

No intention of ever landing off-airport again, unless it's intentional and in someone else's plane.

 

[chrixxer]

2 hours ago, steingar said:

The F has the same engine as the E, but it has a larger fuselage and is therefore heavier.  Given the same power and more weight, it makes some small sense that the new aircraft wouldn't take off with the same alacrity as the old one.

I wasn't expecting it to be identical But I guess maybe I didn't realize 10" and ~100 lbs would make such a huge difference.

[SantosDumont]

I actually use a bit of nose down trim on take off.  I set it just below the black take off trim mark.  Then apply a little bit of back pressure at 65kts and let it fly off the run way.  TCM IO-360-ES tho. YMMV.

[Hank]

Imwas based at an obstructed 3000' field for my first 7 years of ownership. A buddy had an F there which I flew several times. Never had any issues going in or out, but I only flew his F either solo or 2 people and few bags. Like this, I set my trim slightly nose high with no flaps; I believe the F was the same. But the F lands much, much better with Full Flaps. 

Question:  are the flaps in your F selectable in only the 3 marked positions (Up, Takeoff, Landing) or are they infinitely variable like my C? It's much nicer to be able to add or remove just a little bit of flap on final, but that 75 F couldn't do that . . . .

[chrixxer]

41 minutes ago, Hank said:

Imwas based at an obstructed 3000' field for my first 7 years of ownership. A buddy had an F there which I flew several times. Never had any issues going in or out, but I only flew his F either solo or 2 people and few bags. Like this, I set my trim slightly nose high with no flaps; I believe the F was the same. But the F lands much, much better with Full Flaps. 

Question:  are the flaps in your F selectable in only the 3 marked positions (Up, Takeoff, Landing) or are they infinitely variable like my C? It's much nicer to be able to add or remove just a little bit of flap on final, but that 75 F couldn't do that . . . .

The electric flaps on the '69 F are continuously variable.