Gear speed - early 201's

[Pinecone]

That is amazing.  As I teach in safe driver training, if you can reduce your speed by 1/2 before applying the brakes, you cut pad wear by 4 fold.

[Yetti]

On 12/16/2024 at 2:14 AM, Barneyw said:

I'd like to extend this conversation further to earlier aircraft in particular aircraft fitted with Johnson bars. Having now done a few gear cycles I can now understand the strain on, most likely, undersized motors - something that is not necessarily limited to the Mooney. What caught my eye was the speed change occurring with what I assume was a more powerful actuator.

From what I read in the service bulletin a placard change is all that is required and you are good to go no change to the undercarriage etc.

So my question is, is there any structural differences between the undercarriages, and I guess the wing mounting, of the "J" and in my case the "F"

I recently purchased 2 x spindle assy, one off a J and the other unsure, but they are the same part numbers and would imagine if I were to dig a little deeper the whole assy would most likely be the same PNo.

I think you can see where I am going with this so I would like to know if there is any information or experience on a VLe and VLo for the "F" because at the moment all I have is one speed and that's 105KIAS in a rather light on flight manual and POH.

If the answer is in the negative can they please explain why.

Cheers

Barney 

I have been researching the wing between the 1970s model F, the J and the K for the DYNON Autopilot.   From what I can tell the wing is the same between the 3 models up to the part numbers for the wing skins.   The one thing that was going on during the late 70s is the electric gear actuator was changing models.    For the 75 F the gear extend speed is 120mph.   I did just read that the flap extend speed is 125mph and the white arc is 125 mph.

 

[A64Pilot]

On 12/15/2024 at 10:37 PM, philiplane said:

slower gear extension is better. Throwing out the gear at the max speed allowed is poor form and rips up the gear doors and linkages. There is neat feature on all Mooneys that can save fuel, maintenance costs, and aggravation when slowing down to land. It's conveniently placed in front of of the pilot. It works every time/

The throttle.

This

Personally I delay gear down until top of the white arc, because my airplane is geriatric and as I have Certified a few CAR 3 airplanes myself I know that there is no consideration for aging components in Certification, I believe there is some verbiage that fatigue of the airframe must be considered without any definition of what that means. I also retract gear at the slowest speed possible, in fact I think maybe retraction is even harder on the actuator and linkages etc than extension, but I don’t have any proof of that it comes from an opinion, and we all know what those are worth.

Other than being taught to do it by CFI’s that have zero mechanical aptitude or experience I can’t figure out why a person who won’t pull max G’s every flight or push to VNE on every descent etc thinks nothing of hitting that gear switch the instant it’s allowed.

Now if I could purchase a new Eaton actuator and the rest of the parts were readily available, then maybe I’d relax my attitude some.

Oh, and it’s honestly not at all hard to slow a J model down, you just start a little earlier is all. 

On edit, I’ll often descend 100 ft lower than pattern altitude, then climb the 100 back, the climb when at low power really drops speed of course.

 

Edited December 20 by A64Pilot

[A64Pilot]

4 hours ago, Pinecone said:

That is amazing.  As I teach in safe driver training, if you can reduce your speed by 1/2 before applying the brakes, you cut pad wear by 4 fold.

You will also save a BUNCH of fuel too if you lift the throttle when the light ahead turns yellow. Drives me nuts to watch these people who accelerate until they hit the brake, it doesn’t save them any time, nobody is going until the light turns green, so why do they do it?

[philiplane]

1 hour ago, A64Pilot said:

You will also save a BUNCH of fuel too if you lift the throttle when the light ahead turns yellow. Drives me nuts to watch these people who accelerate until they hit the brake, it doesn’t save them any time, nobody is going until the light turns green, so why do they do it?

Because the active traffic sensors (eddy current loops) buried in the road will sense more cars at the light, and change it to green faster. That is why you're better off getting to the light faster when the lights are closely spaced. You also want close spacing between cars, not the 2-3 cars lengths some people leave in between. More density means that when the light turns green, it will stay green longer to accommodate all those vehicles. 

[jetdriven]

6 hours ago, Pinecone said:

That is amazing.  As I teach in safe driver training, if you can reduce your speed by 1/2 before applying the brakes, you cut pad wear by 4 fold.

Brake pads and rotors are consumables,

[Fly Boomer]

7 hours ago, Pinecone said:

I did make it to 99,935 on a set of front brake pads.

177,000 on mine.  Won't be long now.

[Pinecone]

1 hour ago, philiplane said:

Because the active traffic sensors (eddy current loops) buried in the road will sense more cars at the light, and change it to green faster. That is why you're better off getting to the light faster when the lights are closely spaced. You also want close spacing between cars, not the 2-3 cars lengths some people leave in between. More density means that when the light turns green, it will stay green longer to accommodate all those vehicles. 

Look at the sense loops.  There is normally just one per lane, at the point a car would stop.  

I doubt they put in multiple sense loops to determine that there are more cars.

[Pinecone]

58 minutes ago, jetdriven said:

Brake pads and rotors are consumables,

Yes, but for street driving, long front pad life is indicative of a safer driver, who is looking further ahead to reacting to things well before they are an issue.

[EricJ]

On 12/18/2024 at 9:54 PM, Buzzbomb said:

Thanks everybody for the feedback.  I did find the service bulletin requiring a placard on the panel and update in the POH.  Presumably that tells us the '77 and later gear is the same, or at least tested to the same stresses.  

No disagreements regarding the obvious advantages to dropping gear at much lower speeds.  I too, am like that driving my cars.  I've got a 300,000 mile Honda that still has factory brakes on the rear wheels.  There are those times however, in aircraft when we need to slow a bit quicker than preferential.  That's when those higher gear speeds are fantastic and a couple cycles at the higher speeds isn't going to hurt a thing. 

Rear brakes, especially on a FWD car, don't do much, so it's not unusual for them to last a very long time.    On one of my FWD race cars I disabled the rear brakes entirely (to prevent damaging the inside rear tire under trail braking on corners).   It made no appreciable difference in performance or handling.

[PT20J]

6 minutes ago, EricJ said:

Rear brakes, especially on a FWD car, don't do much, so it's not unusual for them to last a very long time.    On one of my FWD race cars I disabled the rear brakes entirely (to prevent damaging the inside rear tire under trail braking on corners).   It made no appreciable difference in performance or handling.

Then you can' t do those cool handbrake turns when the bad guys are chasing you 

[MikeOH]

1 hour ago, Pinecone said:

Look at the sense loops.  There is normally just one per lane, at the point a car would stop.  

I doubt they put in multiple sense loops to determine that there are more cars.

You need to get out more

VERY common to have multiple sense loops here in southern California (you can see them in the paving).  Absolutely affects wait times at signals.  The other annoying thing is the programming of multiple signals in a row; if you make one, you are likely to make the rest.  OTOH, missing one will nearly guarantee missing the others; speeding out of a light to make the 'yellow' of the next will result in making all the lights.  Yes, reprehensible behavior but is one reason you see people accelerate madly out of a signal.

[A64Pilot]

1 hour ago, MikeOH said:

You need to get out more

VERY common to have multiple sense loops here in southern California (you can see them in the paving).  Absolutely affects wait times at signals.  The other annoying thing is the programming of multiple signals in a row; if you make one, you are likely to make the rest.  OTOH, missing one will nearly guarantee missing the others; speeding out of a light to make the 'yellow' of the next will result in making all the lights.  Yes, reprehensible behavior but is one reason you see people accelerate madly out of a signal.

Most of the lights I have experience with are timed as in once you get the cadence right then you will make every, or almost every one, the timing doesn’t vary from 3am with no traffic to rush hour. Every so often you hit lights that there seems to be no timing at all, they seem random, I’ve always assumed those are not networked

Apparently none of the ones I’ve been around have the ability to adjust timing based on traffic density either, because the length of time the light stays green is the same whether there is one car waiting, or 20, when it’s 20 you may have to wait several cycles, when it’s like that I often go past and turn around.

I suspect most of the US thankfully is not like S Cal. I couldn’t live in that kind of density myself.

I don’t expect to ever have to put new pads or rotors on, car I just sold had 50K on it, and the brakes were worn maybe 10%? Except to hold the car once stopped they were only rarely used (regen braking does all normal braking)

Edited December 21 by A64Pilot

[A64Pilot]

2 hours ago, EricJ said:

Rear brakes, especially on a FWD car, don't do much, so it's not unusual for them to last a very long time.    On one of my FWD race cars I disabled the rear brakes entirely (to prevent damaging the inside rear tire under trail braking on corners).   It made no appreciable difference in performance or handling.

What race car is front wheel drive? I haven’t raced cars for 40 years but then it was only two, old mini-cooper which had its own series and the Renault R5, the Le-Car, which was only technically a race car as it was raced in SSCA C class show room stock against the mighty Chevy Vega. Renault handled better until it rolled but the Vega had more power, in other words they were both turds, but they were fun because all cars were evenly matched.

Rear brakes while it’s true do very little braking yet they are important, they do help in stopping and sometimes will keep the back end where it belongs, some motorcycle road racers put thumb brakes on the rear on the left handle bar, when braking in a hard turn without a tiny bit of rear brake the rear would step out, even if they do no braking at all they absorb the inertia of the drive train that will act to push the vehicle forward under hard braking.

[MikeOH]

@A64Pilot

Yeah, the 'traffic density' is pretty horrific, at times.  I'd lose my ever loving mind if the signals didn't adjust for time of day and traffic density.  Most are pretty well engineered in urban areas.  E.g., late at night (low traffic) pull up at a left-turn pocket and it will sense you and change green right away; i.e. it doesn't make you sit through a cycle if there is no conflicting traffic.

[Will.iam]

3 hours ago, MikeOH said:

You need to get out more

VERY common to have multiple sense loops here in southern California (you can see them in the paving).  Absolutely affects wait times at signals.  The other annoying thing is the programming of multiple signals in a row; if you make one, you are likely to make the rest.  OTOH, missing one will nearly guarantee missing the others; speeding out of a light to make the 'yellow' of the next will result in making all the lights.  Yes, reprehensible behavior but is one reason you see people accelerate madly out of a signal.

Lights timed at 30mph can be made at 60mph too. Just saying. 

[philiplane]

6 hours ago, Pinecone said:

Look at the sense loops.  There is normally just one per lane, at the point a car would stop.  

I doubt they put in multiple sense loops to determine that there are more cars.

The loops cover way more than you might expect. I'm involved in the control logic business.

[Hank]

10 hours ago, MikeOH said:

@A64Pilot

Yeah, the 'traffic density' is pretty horrific, at times.  I'd lose my ever loving mind if the signals didn't adjust for time of day and traffic density.  Most are pretty well engineered in urban areas.  E.g., late at night (low traffic) pull up at a left-turn pocket and it will sense you and change green right away; i.e. it doesn't make you sit through a cycle if there is no conflicting traffic.

I've been driving since 1977, and have never knowingly been through a light like that. Need to find and update my spreadsheet listing states visited and driven around in, it must be > 40. But haven't driven in Kali, either too young or just taxi and walking around downtown SF before it went awry.

If I had $1 for every light I've sat waiting out the timers to make a left turn with zero traffic going the other way . . . . Yes, even between midnight and 0500.

[Barneyw]

On 12/21/2024 at 3:55 AM, Yetti said:

I have been researching the wing between the 1970s model F, the J and the K for the DYNON Autopilot.   From what I can tell the wing is the same between the 3 models up to the part numbers for the wing skins.   The one thing that was going on during the late 70s is the electric gear actuator was changing models.    For the 75 F the gear extend speed is 120mph.   I did just read that the flap extend speed is 125mph and the white arc is 125 mph.

 

I guess that's what I want to explore if the increase speed (VLo VLe) was coincidental with the actuator change and a paperwork exercise and if there is any structural difference between the F and the J given, as you alluded to, it all appears to be the same.

Not sure where the thread took a turn and starting talking brakes but if there is anyone out there who could answer the questions that would be helpful.

Cheers  

[PT20J]

The first M20Js (1977) were really just M20Fs with some aerodynamic mods. Mooney kept S/N 24-0084 and worked out additional improvements that were incorporated in 1978 model year starting with S/N 24-0378. One of those changes was to replace the Dukes/ITT actuators with the Avionics Products/CONDEC actuators (most recently manufactured by Eaton after various corporate mergers and acquisitions). Starting with 24-0378, the gear speeds were also increased. But, it might only be coincidental that the increased gear speeds coincide with the actuator change because Mooney changed a lot of things in 1978 and subsequently issued SB M20-209 that provided approved data for using the higher gear speeds with the 1977 models without any physical changes to the airplane.

Still, if I had a Dukes (especially if it still had the 20:1 gears), I wouldn't push it. Bill Wheat said in the "Boots on the Ground" video that Mooney changed the actuator vendor because it felt the old one wasn't up to the job (or something similar -- I forget the exact quote).

 

EDIT: I should have pointed out that the 1977 M20J also introduced the IO-360-A1B6D engine.

Edited December 22 by PT20J

[Will.iam]

On 12/16/2024 at 6:29 AM, ArtVandelay said:

I can’t get down to 80 without using the speed brakes or go into a climb, Js have a 15” MP limitation.

Of course I can do the latter in VFR, but IFR you can’t plan and have often been slam dunked, speed brakes become a necessity in that case.

I’ve had a bracket holding the gear door break on both my doors, I now wait for 120 or less.

Is that 15” mp limitation where the gear horn sounds or a lycoming limitation? And if truly 15” is a limitation, how do you flare to land? Or what about taxiing? 
and if it is the limitation then just lean very LOP and the power will drop off and you are still above 15” once you are slow enough to drop gear then you could richen backup. I have trained myself through repetition to always on go-around push knobs in from right to left thus full mixture full prop rpm then full throttle. As 99% of the time I’m landing while still LOP and engine is already leaned out for taxi. Why run overly rich for that 1% chance go-around? And if by chance you did push the throttle in before the mixture, the coughing and sputtering with lack of power will quickly remind you to push in the mixture knob no different than on initial takeoff if you forget after taxiing lean. 

[ArtVandelay]

Is that 15” mp limitation where the gear horn sounds or a lycoming limitation? And if truly 15” is a limitation, how do you flare to land? Or what about taxiing? 
and if it is the limitation then just lean very LOP and the power will drop off and you are still above 15” once you are slow enough to drop gear then you could richen backup. I have trained myself through repetition to always on go-around push knobs in from right to left thus full mixture full prop rpm then full throttle. As 99% of the time I’m landing while still LOP and engine is already leaned out for taxi. Why run overly rich for that 1% chance go-around? And if by chance you did push the throttle in before the mixture, the coughing and sputtering with lack of power will quickly remind you to push in the mixture knob no different than on initial takeoff if you forget after taxiing lean. 

It’s placarded as continuous, so pulling power to land is ok obviously. I try not to go below that on descents and wait till I’m at pattern altitude. How long is continuous?

[Will.iam]

9 minutes ago, ArtVandelay said:

It’s placarded as continuous, so pulling power to land is ok obviously. I try not to go below that on descents and wait till I’m at pattern altitude. How long is continuous?

Well if you really wanted to slow down and keep the MP above 15” then you could just pull the fuel mixture to cutoff but that would be frowned upon by the faa and not good for shock cooling the motor.  Everybody complains about how flying LOP loses speed and is not a fast as ROP, here it helps slow down and save gas. Also turning the lowest RPM you can in descent helps slow down and keeps the high speed from driving the propeller. Also keeps that combustion in the cylinder just that little bit longer to heat the cylinders but the less firings per minute results in more cooling of the cylinders than the little extra time the flame is in the chamber. 

[Pinecone]

On 12/20/2024 at 7:13 PM, MikeOH said:

You need to get out more

VERY common to have multiple sense loops here in southern California (you can see them in the paving).  Absolutely affects wait times at signals.  The other annoying thing is the programming of multiple signals in a row; if you make one, you are likely to make the rest.  OTOH, missing one will nearly guarantee missing the others; speeding out of a light to make the 'yellow' of the next will result in making all the lights.  Yes, reprehensible behavior but is one reason you see people accelerate madly out of a signal.

CA is not the rest of the country.

 

[Pinecone]

On 12/21/2024 at 7:48 AM, Hank said:

I've been driving since 1977, and have never knowingly been through a light like that. Need to find and update my spreadsheet listing states visited and driven around in, it must be > 40. But haven't driven in Kali, either too young or just taxi and walking around downtown SF before it went awry.

If I had $1 for every light I've sat waiting out the timers to make a left turn with zero traffic going the other way . . . . Yes, even between midnight and 0500.

What he describes is somewhat common in MD.  Not all lights, but many.

And the left turn stays green (up to a point) until 8 seconds without a car in the turn lane.