Yoke, Flaps, Brakes, and Landings

[Wistarmo]

According to my POH, Section V, "Normal Landing Distance", the recommended approach speeds are 70 kts at 2300 lbs, 74 kts at 2600 lbs, and 78 kts at 2900 lbs, with full flaps.  I am not working out of short fields, however, and in hot and humid Florida I usually avoid fields less than 3000 feet.  Rather than try and specify for others an exact speed for their approaches and landings, I think what I would like to communicate is that one speed doesn't fit all weights and each pilot should see what works for their aircraft under a variety of loading conditions.  For me and my plane, coming in solo at 70 kts leads to floating down the runway, and coming in with three passengers at 70 kts leads to a teeth-jarring landing.

 

[fantom]

I believe those are approach speeds used for simple, and conservative, landing distance charting purposes only. Nothing recommended about them, and they are fast!

At 2,500 lbs gross weight, with gear and flaps down, a decent Mooney driver IMO can touch down at 1.15 of the 53 KIAS stall speed, or just over 60 knots. At 2740 lbs, same configuration, and 1.2, that's still about 65 knots.

Seems to me that it isn't so much what speed works for the plane as it is what speed works for the pilot. YMMV.

[Magnum]

Quote: Wistarmo

According to my POH, Section V, "Normal Landing Distance", the recommended approach speeds are 70 kts at 2300 lbs, 74 kts at 2600 lbs, and 78 kts at 2900 lbs, with full flaps.  I am not working out of short fields, however, and in hot and humid Florida I usually avoid fields less than 3000 feet.  Rather than try and specify for others an exact speed for their approaches and landings, I think what I would like to communicate is that one speed doesn't fit all weights and each pilot should see what works for their aircraft under a variety of loading conditions.  For me and my plane, coming in solo at 70 kts leads to floating down the runway, and coming in with three passengers at 70 kts leads to a teeth-jarring landing.

 

[alex]

Quote: piperpainter

I am so used to putting my flaps up for all the short fields I go to I've made it habbit and it really does help braking action getting them up quickly! The flap handle is just to the right of the throttle a bit so it's a fluid motion for me! Kind of like putting my gear up right after takeoff!

[Piloto]

Quote: sleepingsquirrel

As far as AOA indicators, why wouldn't a woolen yarn trailing from the OAT give AOA? Given  that sailors use tell tales to see flow separation why couldn't I use a yarn on the wing to see the same thing?

 

 

[sleepingsquirrel]

Quote: Piloto

 Because when it get wet or frozen it no longer works.

José

[Wistarmo]

To fantom: If they are in my POH, there is nothing recommended about them?  Yes, I can touch down at 2500 lbs and 60 kts or 2740 lbs and 65 kts.  I can cetainly do that if that is my goal.  I am not trying to land at the slowest possible speed or the shortest possible distance.  I am trying to get the smoothest, most reproducible landing I can.

To Magnum: Forgive me if I misunderstand your question, but I am unable to find a "maximum performance landing"  in my POH.  If you could direct me, I would be interested in finding that table.  My POH only has tables for "Normal Landing" on "Hard Surface" and "Normal Landing" on "Grass Surface".  That is all that I am trying to do, a normal landing.

[Shadrach]

Quote: Wistarmo

According to my POH, Section V, "Normal Landing Distance", the recommended approach speeds are 70 kts at 2300 lbs, 74 kts at 2600 lbs, and 78 kts at 2900 lbs, with full flaps.  I am not working out of short fields, however, and in hot and humid Florida I usually avoid fields less than 3000 feet.  Rather than try and specify for others an exact speed for their approaches and landings, I think what I would like to communicate is that one speed doesn't fit all weights and each pilot should see what works for their aircraft under a variety of loading conditions.  For me and my plane, coming in solo at 70 kts leads to floating down the runway, and coming in with three passengers at 70 kts leads to a teeth-jarring landing.

[Shadrach]

Quote: Wistarmo

To fantom: If they are in my POH, there is nothing recommended about them?  Yes, I can touch down at 2500 lbs and 60 kts or 2740 lbs and 65 kts.  I can cetainly do that if that is my goal.  I am not trying to land at the slowest possible speed or the shortest possible distance.  I am trying to get the smoothest, most reproducible landing I can.

To Magnum: Forgive me if I misunderstand your question, but I am unable to find a "maximum performance landing"  in my POH.  If you could direct me, I would be interested in finding that table.  My POH only has tables for "Normal Landing" on "Hard Surface" and "Normal Landing" on "Grass Surface".  That is all that I am trying to do, a normal landing.

[Wistarmo]

To be accurate, the speeds I am quoting are not the speeds at which the aircraft is touching down.  They are over-the-threshold speeds at which I begin "rounding out" or entry into the flare.  Vso for my aircraft at max. gross weight is 58kts according to the POH. Vref is 1.3 times that or 75.4 kts.  According to FAR 23.73, Vso times 1.3 is the minimum speed for Vref.  As stated in the Pilot's Handbook of Aeronautical Knowledge, "The effect of proper landing speed is important when runway lengths and landing distances are critical. The landing speeds specified in the AFM/POH are generally the minimum safe speeds at which the aircraft can be landed. Any attempt to land at below the specified speed may mean that the aircraft may stall, be difficult to control, or develop high rates of descent." 

I note that it is also recommended that final approach speed be Vref plus ten knots:

"Planning the Landing

As in the takeoff, the landing speeds shown above should be precomputed and visible to both pilots prior to the landing. The VREF speed, or threshold speed, is used as a reference speed throughout the traffic pattern or instrument approach as in the following example:

VREF plus 30K Downwind or procedure turn

VREF plus 20K Base leg or final course inbound to final

fix

VREF plus 10K Final or final course inbound from fix

(ILS final)

VREF Speed at the 50 foot height above the

threshold. " 

 

 

 

[fantom]

The POH is very specific in NOT labeling those speeds on the first chart as either "suggested" or "recommended" because they aren't. FAR and the Pilot's Handbook have lots of good general data, and if that's your source for determining Mooney landing speeds, and it works for you, then so be it, but you're coming in too fast. Some slow flight, just above a stall, and maybe holding it off at 5 feet all the way down a runway with a Mooney experienced CFII will help.

As I and others have suggested, try 1.2 X the stall speed shown on your second graph as your over the numbers flair target, and you'll get safer landings, fewer teeth jarring touchdowns, shorter rollouts, less stress on your landing gear, lowered chance for fuel leaks, less probability of a prop strike, and still be able to impress your passengers with greasers. I guarantee it.

Suspecting you don't believe me when I say your dragging it in too hot, maybe Bob Kromer, former Mooney test pilot, Mooney President and MAPA Director can help you:

http://www.mooneypilots.com/mapalog/M20J%20Evaluation/M20J_evaluation_report.html

Good luck, and come to a Florida luncheon again so we can discuss it further.

[PTK]

Quote: txbyker

Being relatively new at Mooney ownership (1987 M20J) I have some questions for you guys in regards to landings.  What do you do with the yoke when all 3 wheels are down, leave it neutral, keep elevators up, push them down, flaps at full?

The reason I ask this is that when I land I seem to continue to float down the runway even though all three wheels are down and throttle is at idle.  If I apply the brakes hard to try to slow before a taxiway exit I can skid very easily which tells me I dont have a lot of weight on the tires.  I have missed a desired exit or two.

Do you push forward on the yoke to create more weight on the wheels or just leave it neutral?  I have a lot of hours in C172s and was taught often to keep the yoke back and noise up to lighten weight there.  I might be favoring a pulled back yoke position which in my mind will keep the plane light on the wheels.

[Wistarmo]

"Using the stall speeds derived above, let's set some approach speeds and shoot some landings to get a feel for the airplane in the pattern and in the landing flare. Using our old rule of multiplying the stall speeds times 1.2 to determine "over the threshold" speeds, we come up with 1.2 times 58 KIAS = 70 KIAS with the flaps up and 1.2 times 52 KIAS = 62 KIAS with the flaps full down. I know these numbers sound low -- they did to me. But let's try them out in a series of landings.

I like to fly the pattern in a J model at 100 KIAS. I use this speed for my climb, crosswind, downwind and base. On final, I begin slowing to 80 KIAS and am at my targeted threshold speed of 1.2 times the stall speed as I enter the landing flare. My first few landings were done with the flaps up. All Mooneys land very well with the flaps up, just expect a pretty high nose up attitude on final approach. Our calculated threshold speed of 70 KIAS with the flaps up sounded slow to me, but guess what? It was perfect! The airplane had plenty of energy left to flare and float before touching down. I next tried the targeted threshold speed of 62 KIAS over the numbers with the flaps full down. Again, perfection! Good energy left for the flare and touchdown. At no time did I feel the airplane was going to fall out from under me. Remember, my stall speeds and calculated "over the numbers" speeds were done with about three-quarters fuel, only me and 30 pounds of equipment on board. With more fuel or passengers, these speeds would have increased by 5 knots or so. But that's all. "-- from Bob Kromer's post.

He is using a Vref of 1.2 times a Vso of 52 kts at unknown gross weight (by himself, partial fuel), yielding a threshold speed of 62 kts.  As mentioned, when I am solo I use 65 kts.  I don't see this as substantially different.

However, I am completely unable to find any reference anywhere that suggests 1.2 Vso is a correct approach speed-- Mr. Kromer's "old rule." I am not an instructor, but the PTS for landings, the Airplane Flying Handbook, and the Pilot's Handbook of Aeronautical Knowledge all use 1.3 Vso.  (Our airspeed indicators are actually only required to be especially accurate between 1.3 Vso and Vne, FAR 23.123). The difference between 1.2 Vso (69.6) and 1.3 Vso (75.4) alone is almost 6 knots with a Vso of 58 knots.

Where I am finding a difference is at the higher gross weights.  I am using a Vref of 1.3 times a max. gross weight Vso of 58 kts, leading to an approach speed of 75.4 kts, with perhaps an additional 2-3 kts added when fully loaded on a hot day, which is close to the 78 kts shown in my POH.  

I do not question anyone's experience in their own aircraft and what works well for them.  There clearly is a significant experiential difference between flying the POH and flying the airplane. It would be great if anyone can show me a reference where 1.2 Vso is a recommended approach speed.  

 

[Hank]

All I can say is, if you're trying to land at 78 KIAS per your calculations, and you're floating across town while doing so, try coming in slower. Get some slow flight practice, then come in 3 knots slower; if you keep on floating, knock off another 3 knots, until you are making good landings. Write that number down, figure your weight, and repeat it in the future. A good rule of thumb is +5 knots for every 300 lbs. heavier, and -5 for every 300 lbs lighter.

Sounds to me like you are landing light, but using max gross speeds. My Owner's Manual gives landing performance numbers based on two gross weights, and states "Full Flaps, 80 MPH, Power OFF, NO WIND."  The longest number shown is 1795 feet, at max gross, 7500 msl elevation, obstacle clearance + ground roll. You are heavier, so yours will be longer, and is written in KIAS, so expect different numbers but not hugely different speeds.

[Shadrach]

@Wistarmo-

If it works for you then go for it. Perhaps your ASI is optimistic at slow speeds. 1.3 Vso is a good rule of thumb for most AC. I feel that 1.2Vso works far better in Mooneys (1.1Vso shortfield) because of the fact that they tend to realize more of a ground effect cushion due to the proximatey of the wing to the ground when compared to a highwing or even some of the taller low wings. The speeds above are what I use for short final and flare.

It's no myth that Mooneys are not as forgiving as other less clean, non laminar airframes. In my plane, 5 knots does in fact make a big difference (depending on your definition). I'd say it equates to ~400-500ft depending on conditions.

In your original post you listed flare and underlined it before listing your speeds...

"I have a '93 M20J (MSE) and I try to flare at 65kts by myself, 70kts with one passenger, 75kts with two passengers, and 80kts with 4 passengers.  My short final speed is about 5kts higher."

80kts is about 1.4Vso and is a bit fast over the numbers, and more so in the flare. The 80 in the flare statement is probably what got everyone asking. At the weights most of us fly, a Mooney won't flare at 80kts...it will climb as soon as you raise the nose.

 

[fantom]

"It would be great if anyone can show me a reference where 1.2 Vso is a recommended approach speed."

If you don't trust Mr. Kromer's "old rule" (???) come fly with me, my friend!

[Magnum]

Quote: Wistarmo

To Magnum: Forgive me if I misunderstand your question, but I am unable to find a "maximum performance landing"  in my POH.  If you could direct me, I would be interested in finding that table.  My POH only has tables for "Normal Landing" on "Hard Surface" and "Normal Landing" on "Grass Surface".  That is all that I am trying to do, a normal landing.

[M016576]

Or you could just get an AOA gauge and not have to worry about the math, winds, density altitude, gross weight and angle of bank so much... I'm just sayin'! ;-)