Jump to content

M20L Engine Conversion

dellison

By dellison
in Modern Mooney Discussion

 Share

Recommended Posts

KSMooniac Grand Master

KSMooniac

Posted
Posted

The only conversion that was done in the past was the IO-550 conversion, and that STC is lost in the ether.

 

The M20L didn't sell because it performed worse than the 200 HP J, going slower and burning more fuel.  Putting a TSIO-360 on it wouldn't likely result in great performance either due to the weight.  All of the post-M20L factory long-body Mooneys used the TIO-540 or (TS)IO-550.  The M20L was the first long-body, and obviously needed more power.

aviatoreb Grand Master

aviatoreb

Posted
Posted

The only conversion that was done in the past was the IO-550 conversion, and that STC is lost in the ether.

 

The M20L didn't sell because it performed worse than the 200 HP J, going slower and burning more fuel.  Putting a TSIO-360 on it wouldn't likely result in great performance either due to the weight.  All of the post-M20L factory long-body Mooneys used the TIO-540 or (TS)IO-550.  The M20L was the first long-body, and obviously needed more power.

 

There was also a Rocket Engineering liquid rocket conversion.  I forgot the number on that liquid cooled continental but it was rated to 335hp.

KSMooniac Grand Master

KSMooniac

Posted
Posted

Did the liquid Rocket conversion go on an M20L?  I can't remember if it did or not... thought those were on Bravo airframes but I could be mistaken.  I believe there were 5 or less done.  One lived near me for a while, but I never got to sample it.  It surely is the fastest M20 ever made!

carusoam Grand Master

carusoam

Posted
Posted

The ill-powered PFM never got to demonstrate it's real challenges...

MGTW is limited to one person with full tanks.

There has been rapid evolution of the long body since...

Step 1: PFM - low power, low MGTW, longevity and overhaul issues.

Step 2: TLS - better power, better MGTW, but cylinder wear challenged..

Step 3: Bravo - same as the TLS, but better longevity. A great Long Body, but doesn't like LOP.

Step 4: Ovation - 280 N/A hp, good power and excellent longevity (depending), loves LOP.

Step 5: Acclaim - 280 TN hp, good power from the ground through altitude.

Step 6: Ovation 3 - 310 N/A hp, great power, and excellent longevity (depending) balanced for LOP.

Next step: Acclaim 2 - 310 TN hp, great power all the way into the flight levels...

Either way...

Less than 280 hp and N/A Long Body would be considered under powered by most pilots.

The PFM's MGTW is limited at a too low number. Full fuel has enough GW to take the pilot a long distance.

The M20M 270hp? uses up a lot of runway, but makes up for it at altitude.

The N/A 240 hp of the original Eagle usually gets swapped out at first economic chance the owner gets.

Putting a different engine on an airframe requires an STC which can be purchased or it requires a significant testing and documentation program if the STC does not already exist. It would be considered unusual for a person with ordinary means to be able to afford this type of change.

Chasing down the PFM to recreate it would be the equivalent of (insert your version of a very empty feeling)...

Mooney is known for its combination of speed and efficiency. It is often valued for it's built in America status. The longevity of the airframe and engine has been key to it's success.

The PFM was missing these key characteristics.

If you can find a way to put an airworthy engine on it, you have accomplished Step one.

There are PFM airframes and undocumented IO550 engines available. This would be a project for someone with an aviation background that may include engineering and or A&P level mechanic skills.

Best regards,

-a-

Let me know if I missed something. I can edit any mistakes!

  • Like 2
KSMooniac Grand Master

KSMooniac

Posted
Posted

If you're going to go through the hassle of that, stick a Rolls Royce or P&W turbine on the front instead - it doesn't burn Avgas either

 

Except the problem of low MGW + high turbine fuel burn = unfeasible airplane, despite the lower weight of the powerplant up front.  A 400-500 HP turboprop would need a 4000 lb MGW Mooney airframe to make sense IMO, and that ain't gonna happen easily.  The M20 airframe isn't suitable for pressurization either, so it seems a bit silly to have an UNpressurized turboprop IMO.

Parker_Woodruff Grand Master

Parker_Woodruff

Posted
Posted

Did the liquid Rocket conversion go on an M20L? I can't remember if it did or not... thought those were on Bravo airframes but I could be mistaken. I believe there were 5 or less done. One lived near me for a while, but I never got to sample it. It surely is the fastest M20 ever made!

There was at least one that had it

http://www.aircraftmerchants.com/cf/acDetail.cfm?AircraftId=AF4ED3BD-EB93-4D07-A7B1-108F46178B90

aviatoreb Grand Master

aviatoreb

Posted
Posted

Anyone know why there weren't more Liquid rockets?  I have heard that they go 260TAS at max power.  There are extra gussets added to strengthen the frame.

 

Only 5 were made.  Why did Rocket Engineering stop producing this beast?

KSMooniac Grand Master

KSMooniac

Posted
Posted

Rocket had nothing to do with the hurricane and related carnage in FL.  I think the market for their conversions was rapidly going away because Mooney started building "big engine" M20s straight from the factory, and they realized their market would be shrinking.  They certainly moved on to bigger and more lucrative conversions with turboprop engines and obviously it has worked out nicely for them.

 

I believe the TSIOL-550 came along near the end of their Mooney product line, and of course that engine didn't catch on anywhere else in quantity.

carusoam Grand Master

carusoam

Posted
Posted

The M20L aftermarket took a big hit with the hurricane... Destroying a large part of the existing client base.

TNIO550 from the Mooney factory took care of the forward looking part of the client base. Now rated at 310hp(?)

Fuel usage goes too high for even the select few owner operators at this level?

Liquid cooling is not well received in GA at this time?

Rocket engineering can't make enough dough in this market?

Turboprops with reversible pitch look cool?

-a-

  • 8 months later...
carusoam Grand Master

carusoam

Posted
Posted

As posted above....be sure to check it's MGTW in this case, with Aux fuel (Monroy fuel tanks).

350hp is plenty of power to get off the ground...

There is something missing in the safely return them to earth portion of the eqution.

May need new powerful legs and associated support and mounting hardware...?

The newer long bodies got new landing gear specifications for this challenge.

LBs have a MGTW with a lower max landing weight...

It's only a problem at full gross T/O when an immediate need to land arises...

It may only be a legal challenge if it is operated outside FAA jurisdiction. Keep in mind the physical changes will not change by landing it on New Zeeland soil....

Best regards,

-a-

Welcome aboard Sailnz!

aviatoreb Grand Master

aviatoreb

Posted
Posted

I have heard that there are exactly 5 liquid rockets.  I have heard that they actually strengthened the airframe with gusset welds in a few places.  But I thought liquid rockets were 335hp.  I wonder if that one is modded the 335 up to 350?  They are supposed to be faster than the normal garden variety vanilla rocket - they are reputed to go 260kts. 

 

They are way cool.

 

But the nice thing about a standard rocket is that it is built out of common parts - those TSIO520nb engines are in many Cessna airplanes.  I would worry that the engine would not be supported in the future in the liquid rocket.

  • Like 1
KSMooniac Grand Master

KSMooniac

Posted
Posted

One of my Rocket owning friends flirted with purchasing a Liquid Rocket first, but eventually wised-up and realized that supporting that engine is a scary proposition.  I believe Maxwell recommends owners go to RAM in Waco for engine work since they did a few conversions with the same engine.  Another Rocket owner friend actually had a Liquid Rocket in addition to his normal Rocket...and then sold the Liquid one for the same reason.  It sure was a hot rod, though!  I wish I could have flown it at least once before it moved away...

aviatoreb Grand Master

aviatoreb

Posted
Posted

One of my Rocket owning friends flirted with purchasing a Liquid Rocket first, but eventually wised-up and realized that supporting that engine is a scary proposition.  I believe Maxwell recommends owners go to RAM in Waco for engine work since they did a few conversions with the same engine.  Another Rocket owner friend actually had a Liquid Rocket in addition to his normal Rocket...and then sold the Liquid one for the same reason.  It sure was a hot rod, though!  I wish I could have flown it at least once before it moved away...

 

I wish I could ride in one too....

 

I don't want to own one.

  • 3 weeks later...
carusoam Grand Master

carusoam

Posted
Posted

A couple of things come to mind with that system...

How much liquid is in the system?

Where is it's CG?

What happens to CG when it leaks out?

Simple fitting failure should not lead to a W&B challenge that makes the resulting overheating problem look small.

Best regards,

-a-

  • 2 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
 Share
Go to topic listing
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.