Tach placard

[chrixxer]

I have the IO360-A1A in my E, with a Hartzell HC-C2YK-1BF/F7666A-2 prop (not original). Am I reading this right, that no placard is required? I can't find this exact configuration in the matrix; there's the HC-C2YK hub with the 7666 blade (not F7666A-2), which should read “Avoid continuous operation between 2000 and 2350 RPM,” but again, nothing for my specific configuration. I’ve found myself operating in that range inadvertently on final (power pulled all the way back and not felt any vibration (though I know it's subtle)... I'll ping Hartzell too, of course. (And Lycoming?) The tach is original and has the original range marked on it (but it's slated to get replaced with a digital cluster).

Source: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/45911b31a312cf79862576e8004c87c7/%24FILE/P-920.pdf

[Cody Stallings]

Yes it needs to be placarded.

F7666A(76 inch) Has never been on the Mooneys.

7666A-2 or F7666A-2(74 inch) is the most common Propeller you will find on a Mooney.

The F on your blade design is a later model of the 7666A-2 Blade, with the larger pitch change knobs on the butt of the blades.

Short of that, the blades are the same.

Make no mistakes, continuous operation in the placarded range could spell problems down the road.

[chrixxer]

1 hour ago, Cody Stallings said:

Yes it needs to be placarded.

F7666A(76 inch) Has never been on the Mooneys.

7666A-2 or F7666A-2(74 inch) is the most common Propeller you will find on a Mooney.

The F on your blade design is a later model of the 7666A-2 Blade, with the larger pitch change knobs on the butt of the blades.

Short of that, the blades are the same.

Make no mistakes, continuous operation in the placarded range could spell problems down the road.

Going by the linked document, there's only one entry for the F7666A-2 (but only for the O-360-A1F6D, not the IO-360-A1A), and it specifically says "none" under "placards."

Hartzell has this combo, and specifies: "With IO-360-A1A, A1B engines: Avoid continuous operation between 2000 and 2350 RPM." (page 988 of 1684: http://hartzellprop.com/wp-content/uploads/159-0000-R58-WA-1.pdf) Okay, that's solved... (Why does the POH list power settings in that RPM range? The prop this plane came with had similar limitations.)

Edited July 20, 2017 by chrixxer

[Guest]

Note 7 on the Mooney Type Certificate covers the restricted range as well.

Clarence

[Cody Stallings]

19 hours ago, chrixxer said:

Going by the linked document, there's only one entry for the F7666A-2 (but only for the O-360-A1F6D, not the IO-360-A1A), and it specifically says "none" under "placards."

Hartzell has this combo, and specifies: "With IO-360-A1A, A1B engines: Avoid continuous operation between 2000 and 2350 RPM." (page 988 of 1684: http://hartzellprop.com/wp-content/uploads/159-0000-R58-WA-1.pdf) Okay, that's solved... (Why does the POH list power settings in that RPM range? The prop this plane came with had similar limitations.)

What propeller did your E originally come with?

Could it have had a McCauley Prop?

Did someone have a 3 way propeller on it before you purchased it?

[chrixxer]

On 7/20/2017 at 7:25 PM, Cody Stallings said:

What propeller did your E originally come with?

Could it have had a McCauley Prop?

Did someone have a 3 way propeller on it before you purchased it?

Pretty sure it was an old hub Hartzell (I'll check the logs next time I have them in front of me). Mine wears a sticker placard re continuous operation 2000-2350 (IIRC) below 15" MP.

Edited July 24, 2017 by chrixxer

[chrixxer]

Prop before the current prop was: Hartzell HC-C3YR-1RF (s/n DY6446B) (placard: "Avoid cont. ops. Below 15″ btwn. 1950 and 2350 rpm") (that's what's currently on the panel)

Original prop: Hartzell C2YK-1B (s/n CH516) (placard: "Avoid cont. ops. between 2100 and 2350 rpm")

 

Edited July 25, 2017 by chrixxer

[carusoam]

It may be helpful to let Cody know you replied... @Cody Stallings Like that....

it lights a small notification at the top of his screen...

Best regards,

-a-

[Nukemzzz]

Hate to revive an old post, but I have this exact same hub and prop combo on my 66' E.  The Tach has a Red Arch between 2100 and 2350.  Is there also supposed to be a placard somewhere?  Is the conventional wisdom here that this Red zone still applies with my combo?  Prop was installed new in 2005.  IO-360-A1A engine.

[Nukemzzz]

Also... dumb question...how does one find exactly what Placards are supposed to be in a plane?  Seems I should start with what the plane was shipped with...not sure where to find this.

[EricJ]

15 minutes ago, Nukemzzz said:

Also... dumb question...how does one find exactly what Placards are supposed to be in a plane?  Seems I should start with what the plane was shipped with...not sure where to find this.

The POH should have all required factory placards.   If the airplane has any STCs there may be placards that are required to go with those, too.   

[carusoam]

The challenge with tach rpm limitations and placards...

Many have changed midway through the years... long after the equipment was installed originally...

The place that would have this recorded... is most likely to be the documents where the new prop got installed...

Log books, and STC data are one source... POH updates would be the other source...

MS has a super prop guy that can be extra helpful for these kinds of details... See if @Cody Stallings is around...

My M20C had its tach limitations changed... the red zone expanded a small amount... the FAA found it acceptable to use a red decal on the front of the exterior of the tach...

Over time... the color red probably isn’t the proper color to be used for this... but there weren’t any flashing yellow lights around either... at the time...

Best regards,

-a-

[M20F-1968]

I have a F7666A-2,   HC-C2YK-1BF Hartzell Propeller on my 68 F.  It has a restriction of No Continuous Operations between 2100-2350.   I have been repeatedly told that 

low power situations such as in the pattern are not a problem and are not "Continuous Operations"  and you may operate in this "restricted" range for landing.  This has seemed reasonable to me.  You have to get down and you have to control the airplane when doing so.  Is there anyone here who has information to the contrary?

John Breda

[Cody Stallings]

You should see all your limitations in your POH or Supplemental.

 

[markgrue]

The type certificate data sheet will have limitations and placards listed.  As has been mentioned any stc that changes the placards will have the placards so noted in the stc.

 

Mark

[Yourpilotincommand]

I’m still a newbie here, and have a dumb question.  I have the placard to avoid continuous operation between 2000-2350rpm. Is there a harmonic or vibration in this range that the placard is warning? What is it that I am avoiding exactly? It seems my engine (IO-360-A1A) runs smoothly in all rpms including this range. I do avoid the range for continuous, but want to know what I’m avoiding, lol.

[EricJ]

1 hour ago, Yourpilotincommand said:

I’m still a newbie here, and have a dumb question.  I have the placard to avoid continuous operation between 2000-2350rpm. Is there a harmonic or vibration in this range that the placard is warning? What is it that I am avoiding exactly? It seems my engine (IO-360-A1A) runs smoothly in all rpms including this range. I do avoid the range for continuous, but want to know what I’m avoiding, lol.

Torsional vibration in the crankshaft, where it continually winds up and releases like a rubber band airplane.    

[carusoam]

It exists...

It doesn’t get defined very well...

You still need to transition through it...

When you transition through it... you get extra credit for doing it at low power...
 

Torsional vibration isn’t something you are going to be able to feel...

Unless you have been doing some interesting practice routine for increased seat of the pants sensitivity... 
 

Expect broken welds on the engine mount may be the result of not following the advice....

My M20C broke two welds on the mount... but could not identify what the cause of that was...

PP thoughts only not a mechanic...

Best regards,

-a-