Ultimate Mooney?

[Gary0747]

I know this has been over debated but I wanted to throw this one out there. I was reading in an old MAPA Log (Nov. 1993) that Roy Lopresti as one of his last projects was working on a mid body variant that I think would have been almost perfect for me. He was going to take the 231 and remove the Continental TSIO 360 and replace it with a special variant of the Lycoming IO 540.  It was a parallel valve 260 hp engine that weighed 10 pounds less than the original Continental. 
For us not interested in flying in the flight levels and not liking the massive Continental 520 series and all the issues with reliability, cooling, and having to counter balance the extra weights of the engines in the Rocket Engineering conversions this might have been the perfect Mid body fit.  The Lycoming reliability and likely smaller size of this 540 would have been a major attraction to some that did not prefer the longer body Mooney’s.  I assume this smaller Lycoming 540 variant might have been related to the smaller Lycoming IO360 Variant that is rated at 180 hp?  I never heard what might have happened to Lopresti project.  I think he died not long after this. 

[carusoam]

Fair discussion for a lovely Sunday....

1) More power when desired is always appreciated...

2) Minimal weight increase is very important...

3) If Roy Lopresti was looking into, it already has some merit...

4) Somebody put the Continental six cylinder in the mid-body Mooney, sans turbo... (Mooney Mart)

5) Once going through all the effort to make room for the extra pair of cylinders... take a look at what is available for modern engines of the same size... from both manufacturers...

6) Fly a 300hp Missile... complete and ready to go...

7) then fly a Screamin’ Eagle....  for just a few AMU more....

8) Then add a pair of snails... And maybe some AC... with the built in O2 system...

9) then voilá... Hello Acclaim!

10) It’s a slippery slope.....   enjoy!  

Best regards,

-a-

[aviatoreb]

This is interesting - what engine is this that is 10lbs lighter than a TSIO360 conty but its a 260hp 540 from Lycoming?  I am not familiar.

Separate - I have heard Lycoming is more reliable than Conty.  I have heard Conty is more reliable than Lycoming.  Do you have a reference where I might read about what you assert that the Conty 520s are unreliable?

As for balance - my 520 on the nose, batteries in the tail, and light weight MT on the tip of the nose, is a very balanced mid-body airplane.

[bfreelove]

Would have most likely been a parallel valve IO-540.  The "narrow deck" version of these is quite light and used in a lot of aerobatic applications, the Pitts S-2B and C use the AEIO-540-D4A5, which I don't think is the narrow deck version, but still quite light for the power.  We used a slightly pumped up version of that engine for air racing and it's remarkably robust, able to handle peak power mixtures, 2950 RPM, with minimal cooling (routinely seeing temps at redline) and very high G with no issues and essentially normal lifespan.  I'd love to have that engine in the front of a Mooney.  

[N231BN]

The lightest IO-540 on the TCDS is 373 lbs. A TSIO-360-LB is listed at 354 lbs but that also includes the exhaust system and turbocharger. I doubt the Lycoming weight includes the exhaust.

[N231BN]

I agree that it would be a good fit to the 231 airframe, especially to those of us that like the TO and climb performance of the 231 but have family members that don't care for using O2.

 

My pick would be the IO-550-N at 428 lbs.

 

[Gary0747]

Here is the actual article from 27 years ago.  It sounds like a special Lycoming 540 that may not be available today?  Roy did live another 8 years. And the cowl referenced Or variant of it is available today.  I wonder what Roy thought of the long body Mooney’s And reasons for lengething them, since the mid body’s were his engineering babies. 

[MooneyMitch]

I believe the long body was created as the M20L (Porsche Mooney). 

TLS/Ovation followed along.

[Gary0747]

Was the main reason to lengthen the body to balance the heavier engines?  The ovation is about 20 inches longer than a J but the length added was about 10 inches in the baggage compartment while maintaining the 120 pound limit to baggage there.  I think most of the other 10 inches is in the longer engine?  This lengthening and heavier engines allowed Mooney to continue to claim the speed title even though the extra length no doubt added some to the aerodynamic drag, and did some things with the aerodynamics that caused the factory to say “no slips should be used on final”.  The added weight put the Mooney rubber donut landing gear at the upper design weight limit and dramatically shortened the life of the donuts.    So Lopresti may have some reasoning behind his lighter balanced mid body design. Many have said that the mid body 252 is the best most efficient Mooney ever built. If this is true then a normally aspirated version of that could have been a good seller.  The key here may well have been finding a NA engine close to 100 pounds lighter than the current large 6 cylinder engines. 

[aviatoreb]

I wonder why LoPresti never made that exciting mod.  Do they try it as an experimental and then decline to go certify it or did they just shelve the idea before starting?

[Gary0747]

Good question. Think about the possibilities here.  The empty weight of a mid body 252 is 1800 pounds which is 450 pounds less than an ovation one.  The ovation is supposedly weight limited to about 3360 pounds for taking off because the landing gear design is maxed out.   If the take off weight of the 252 is limited by its raw horsepower at take off and the engine were replaced with a NA engine yielding about the same gross weight as the 252 but having 260 horsepower at take off compared to 280 horsepower of the much heavier ovation one why would it not be able to get much closer to the 3360 take off weight of the ovation one?  The potential here is to have a NA Mooney with close to 1500 pound take off weight!
I wish somebody would show me where my thinking is wrong 

[gsxrpilot]

12 minutes ago, aviatoreb said:

I wonder why LoPresti never made that exciting mod.  Do they try it as an experimental and then decline to go certify it or did they just shelve the idea before starting?

I'm sure there's no way we can ever know... But I can speculate that the Mooney marketing department was chasing raw speed and nothing else mattered. I still think the factory Encore was the best Mooney ever made, but it was shelved after something like 36 units to make room for the Bravo.

[Gary0747]

I agree. I have heard that max speed drove Mooney marketing and this likely overruled sound engineering judgement with the end result being the worlds fastest single engine piston airplane but overlooking the fact that this airplane limited by the landing gear design and costing close to a million dollars would often have 500 pounds or less pay load with full fuel.   Little wonder why Mooney went bankrupt again!  Roy Lopresti was the smartest engineer to work for Mooney and he apparently saw a way around this problem but may not have been listened to.  This design he was working on was after he left the company. 

[carusoam]

What distance do actual Mooneys owners travel..?

My most common flight was between two airports 200nm away...

I think I was surprised by flying round trip and only filling the tanks before I left...

And they were only half filled... leaving plenty of UL for a family of four... 

Now... let’s read this copy... since it has been straightened up...

the date on the article seems to be near the end of ‘94...
 

Curt Lopresti is around here somewhere...  So if you have questions, we can probably ask him directly... 
Seeing if the @Speed Merchant Is around today...

The King’s Mooney is also mentioned in the article... also an MSer’s plane. 

Best regards,

-a-

 

 

[Igor_U]

19 hours ago, gsxrpilot said:

I'm sure there's no way we can ever know... But I can speculate that the Mooney marketing department was chasing raw speed and nothing else mattered. I still think the factory Encore was the best Mooney ever made, but it was shelved after something like 36 units to make room for the Bravo.

I'm sure you could find out from David Lopresti, he's still around. This seems to be LoPresti's company (Speed Merchant) modification (STC?) and not Mooney Aircraft co. LoPresti Aviation is now part of Whelen Engineering...

[Gary0747]

I Phoned David Lopresti and got some info. He said the project was being driven by a management person at Lycoming who was removed for some reason. Apparently another OEM objected to the project not wanting it pursued and the project died. He indicated that everybody involved thought it would be a great idea. 

[LANCECASPER]

On 7/5/2020 at 6:32 PM, gsxrpilot said:

I'm sure there's no way we can ever know... But I can speculate that the Mooney marketing department was chasing raw speed and nothing else mattered. I still think the factory Encore was the best Mooney ever made, but it was shelved after something like 36 units to make room for the Bravo.

Back in 1989 when the TLS (later called Bravo) came out, the TLS and 252 competed for sales, so in 1990 the 252 was discontinued.

They revived the K in 1997 and had the Encore correctly priced between the Ovation and the Bravo.  It probably was taking away some sales of the Bravo, but they were selling 100 plus airplanes a year at the time and IMHO had the best line-up of airplanes in Mooney's history - the Allegro, Ovation, Encore and Bravo. They had a good marketing department. They had salespeople that wanted to sell something at every airplane event, However, in 1997 the Dopp family had just purchased Mooney and the son Chris came in and made changes without even having a clue. Soon into it they scrapped the J and K because the airframes themselves didn't cost much less to build than the long body. Duh! Of course, but they needed different models to appeal to different people. With the line-up they had, they appealed to a wide spectrum of people and if they would have just kept a steady hand things would have been a lot better. There was still a demand for both the J and K when they were scrapped.

[StevenL757]

On 7/5/2020 at 4:32 PM, MooneyMitch said:

I believe the long body was created as the M20L (Porsche Mooney). 

TLS/Ovation followed along.

Exactly.

[StevenL757]

On 7/5/2020 at 2:34 PM, N231BN said:

My pick would be the IO-550-N at 428 lbs.

You have chosen wisely, Obi-Wan.  :-)

[Gary0747]

Dave did not say which OEM had pressured Lycoming to discontinue the Lopresti NA project but I assume it was Mooney with a lot of leverage with Lycoming. Roy may have even had a “ do not compete clause” in his leaving Mooney.  I would have really liked to have seen how this NA small IO540 performed at 450 pounds lighter than the Ovation and only 20 horsepower Less.  I think one of the other stupid moves Mooney made back then is to destroy all the tooling for the mid body so it would be difficult to go back.  

[Andy95W]

29 minutes ago, Gary0747 said:

  I think one of the other stupid moves Mooney made back then is to destroy all the tooling for the mid body so it would be difficult to go back.  

I've heard this same rumor time and again.  I've never heard it confirmed by anyone who would actually know.  

Regardless, "all the tooling" really isn't significant.  A (slightly) different jig for the roll cage, and slightly shorter sheet metal, stringers, etc. for the fuselage.

[N231BN]

I don't know about the mid bodies but they were forced to destroy the M22 tooling as part of the bankruptcy settlement at the time.

[Austintatious]

I see the thread is title "Ultimate mooney"

That would be a pressurized long body Composite version with a 300+ HP turbo-diesel and 105 gallon tanks. 

 

I bet there is 10% more speed to be had with everything being perfectly smooth/faired and composite would allow that.

You would have a 220 knot aircraft that could probably go 2000 miles and no O2 mask required.

[LANCECASPER]

5 hours ago, Austintatious said:

I see the thread is title "Ultimate mooney"

That would be a pressurized long body Composite version with a 300+ HP turbo-diesel and 105 gallon tanks. 

 

I bet there is 10% more speed to be had with everything being perfectly smooth/faired and composite would allow that.

You would have a 220 knot aircraft that could probably go 2000 miles and no O2 mask required.

The only problem is that composite is heavier than aluminum, and a pressure vessel is definitely heavier, so it would have to be a drone.

[MooneyMitch]

On 7/5/2020 at 1:32 PM, MooneyMitch said:

I believe the long body was created as the M20L (Porsche Mooney). 

TLS/Ovation followed along.

In fact, if you watch the first interview segment with Mooney test pilot Mike Miles we filmed during the “Boots” documentary, you’ll see Mike standing in front of the very Porsche Mooney airframe the factory used for initial M20L test flights.