Eagle Upgrade - McCauley

[Ghattig]

I have found several discussions regarding the M20S upgrade STC using the Hartzell 3 blade prop to increase the power output of the engine but cannot find the specs on the McCauley STC# SA00956WI, does it increase the horsepower output? Any sharing of knowledge would be greatly appreciated!

Thanks!

Edited July 10, 2020 by Ghattig
spelling

[Cruiser]

In general the horsepower is determined by the the engine. It maybe limited externally by the governor and accessories. 

The only purpose of propeller change is for optimizing performance in specific sectors of the flight. i.e. take-off, climb, cruise etc. 

the original two blade M20S was optimized for in flight cruise and it set the NA speed record for certified AC at the time it was introduced. Unfortunately, it had a severe limitation in take-off and climb performance. 

Changing to the three-blade prop was a significant improvement on take-off and climb but did impact the cruise performance somewhat. 

 

McCauley STC# SA00956WI was issued to CAV Ice Protection and offers no change to HP. 

The propeller STC -- SA02988AT changes the RPM limitation to 2500 and increases the HP to 280 (same as the M20R)

https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/a758a46bd17ea47a86257014005440aa/$FILE/SA02988AT.pdf

[Ghattig]

Thank you,

That is what I thought and have seen the STC link that you have provided. I was finally able to find the actual McCauley STC# SA00956WI through the search feature on link you provided and you are absolutely correct!! It is only for CAV Ice Protection and offers no change to HP.

Thank you @Cruiser

[Hank]

I thought there was a Screaming Eagle STC that pushed power to 310hp at 2700??? Or is that an engine change too?

[MIm20c]

  On 7/10/2020 at 5:15 PM, Hank said:

I thought there was a Screaming Eagle STC that pushed power to 310hp at 2700??? Or is that an engine change too?

Expand  

Different prop...

[Hank]

  On 7/10/2020 at 5:16 PM, MIm20c said:

Different prop...

Expand  

Isn't @Ghattig looking for prop options on the S?

[MIm20c]

  On 7/10/2020 at 5:17 PM, Hank said:

Isn't @Ghattig looking for prop options on the S?

Expand  

My guess is he already has the McCauley on his plane (or one he is looking at) or is looking at a cheaper option utilizing a take off prop from another plane upgrading.

[Ghattig]

@Hank the plane already has the McCauley STC# SA00956WI and I was trying to determine exactly what the prop added. Only for TKS yet also assume it helps with takeoff and climb, the STC does not add additional RPM/HP

[Ghattig]

@Mlm20c exactly 

[MIm20c]

  On 7/10/2020 at 5:28 PM, Ghattig said:

@Mlm20c exactly 

Expand  

Is the plane currently turning 2400 or 2500 max RPM?

[Ghattig]

2400 RPM - that's why I was seeking the STC information... :-)

[MIm20c]

  On 7/10/2020 at 5:32 PM, Ghattig said:

2400 RPM - that's why I was seeking the STC information... :-)

Expand  

I think the SA02988AT would allow for increasing the 244 hp to 280?  Not sure it’s legal to have the 3 blade prop turning only 2400 max. 

[Ghattig]

@mlm20c

This is the McCauley STC# SA00956WI the plane currently has

https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/790d952c09b8209e86257e26006f505f/$FILE/SA00956WI.pdf

as referenced by @cruiser earlier

 STC -- SA02988AT indeed does increase the RPM/HP

https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/a758a46bd17ea47a86257014005440aa/$FILE/SA02988AT.pdf

 

Thanks Gentlemen!

[carusoam]

If spending money to upgrade...

Go all in...

Turn the ordinary Eagle into a Screamin’ Eagle!

Same engine, updated gov and tach, TopProp.... a tank fill neck mod.... (aka vent hole)

Screamin’ Eagle Performance is amazing...

I learned all this from some CFII named @Cris....  (his posts are still around here)

The STCs for this were acquired by Mooney a few years ago... and defined the O3 power package...

Best regards,

-a-

[Hank]

  On 7/10/2020 at 10:10 PM, carusoam said:

If spending money to upgrade...

Go all in...

Turn the ordinary Eagle into a Screamin’ Eagle!

Same engine, updated gov and tach, TopProp.... a tank fill neck mod.... (aka vent hole)

Screamin’ Eagle Performance is amazing...

I learned all this from some CFII named @Cris....  (his posts are still around here)

The STCs for this were acquired by Mooney a few years ago... and defined the O3 power package...

Best regards,

-a-

Expand  

S + this mod = Screaming Eagle

R + this mod = Standing Ovation?

Didn't realize they were the same package . . . . But both sound like great fun!

[carusoam]

  On 7/10/2020 at 11:38 PM, Hank said:

S + this mod = Screaming Eagle

R + this mod = Standing Ovation?

Didn't realize they were the same package . . . . But both sound like great fun!

Expand  

I met Cris while he was outfitting his Eagle... he was researching the wacky hidden details required to get the 100gal fuel tanks...

He returned the favor by helping me with the details required to update my engine/prop to the Standing O....

+ he also helped me get flying the O again back in the day... 
 

One ride in a Screamin’ Eagle... you know what you need to do next... It earned its name.

Overall, the Screamin’ Eagle weighs a touch less than the O... so it’s the performance king.

The power of MS is amazing...

Best regards,

-a-

[Scottknoll]

  On 7/10/2020 at 5:49 PM, Ghattig said:

@mlm20c
This is the McCauley STC# SA00956WI the plane currently has
https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/790d952c09b8209e86257e26006f505f/$FILE/SA00956WI.pdf
as referenced by@cruiser earlier
 STC -- SA02988AT indeed does increase the RPM/HP
https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/a758a46bd17ea47a86257014005440aa/$FILE/SA02988AT.pdf
 
Thanks Gentlemen!

This STC shows the Hartzell 7693 prop, is there a different STC for the Hartzell 7498 Prop to make the change to 310HP? Hartzell’s sales brochure says the 7498 can be put on an IO550G or an IO550G-AP as modified by STC SE2930AT (Different 310HP STC, also from Mooney, but with no mention of prop). Looking at different props and don’t want to end up with one we can’t do the second STC to (310HP).

[Niko182]

  On 7/15/2020 at 8:21 PM, Scottknoll said:

This STC shows the Hartzell 7693 prop, is there a different STC for the Hartzell 7498 Prop to make the change to 310HP? Hartzell’s sales brochure says the 7498 can be put on an IO550G or an IO550G-AP as modified by STC SE2930AT (Different 310HP STC, also from Mooney, but with no mention of prop). Looking at different props and don’t want to end up with one we can’t do the second STC to (310HP).

Expand  

The 7693 prop was originally designed for the acclaim and the Ovation. The STC came and bumped the Horsepower up to 310hp and the 7693 prop was part of that STC. The 7498 prop came out later and was designed for the Acclaim Type S, but the STC included the Eagle, Ovation, and Older Acclaim within it in order to upgrade. The 7498 prop is the same price as the 7693 but it's 7.5 lbs lighter, and offers about 3 to 5 knots of increased speed. the 7498 is a better prop, offers no downsides, and is the same price. if you're buying new, the 7498 prop is the one you want.

[Scottknoll]

Thanks for clarifying, just wanted to make sure the 7498 prop would still allow our 280HP Ovation IO550G to be converted to 310HP with the T20 governor and fuel system change.

[MIm20c]

  On 7/15/2020 at 8:45 PM, Niko182 said:

 the 7498 is a better prop, offers no downsides, and is the same price. if you're buying new, the 7498 prop is the one you want.

Expand  

The leading edge on the 98 is more delicate. Looks like the 93 with double the amount of hours. Also have to be careful with overhauls, the blades do not have as many in reserve. 

[carusoam]

Hartzell has three versions of TopProp for the O... Acclaim, and Screamin’ Eagle.

1) thick

2) thin aka Acclaim’s prop

3) Composite

The thick version has more life in it for OH down the road...

The thin version is light and speedy... my preference...

The composite is even lighter and can probably make a Charlie weight Un-needed... 2X the UL improvement...
 

Pp thoughts only, the 310hp makes it worth having to get a new prop...

Best regards,

-a-

[carusoam]

  On 7/10/2020 at 2:06 PM, Ghattig said:

1) I have found several discussions regarding the M20S upgrade STC using the Hartzell 3 blade prop
2)  to increase the power output of the engine
3) but cannot find the specs on the McCauley STC# SA00956WI, does it increase the horsepower output? Any sharing of knowledge would be greatly appreciated!

Thanks!

Expand  

Let’s take this one point at a time....
 

1) Where did you look for this, what did you find...?

2) The prop doesn’t do the work, noticeably...

3) The extra hundreds of RPM and related FF does the work...

4) The STC covers the prop, the rpm, and the FF... it’s a package deal...

5) needs a gov adj and a new red line.

6) Yes the package is worth it...

7) Nothing makes you Hope for a ground strike more than this... 

8) if you get saddled with a ground strike... it isn’t all that bad...?

9) Make friends with the Hartzell sales people... they look forward to explaining all of this... plus they have nobody to talk to this month with out KOSH in the plan...

Go Screamin’ Eagle..!

Get a ride in one, You won’t need to write much else...no questions will be needed after that...
 

Except how to get the full 100gal of 100LL in that bird... it is there. You just have to find it...

PP thoughts only... not a mechanic...

Best regards,

-a-