Mooney in Oz Posted September 27 Report Posted September 27 https://asn.flightsafety.org/wikibase/546751 Reported as lack of fuel. Looks like it used to be a nice Porsche Mooney.
LANCECASPER Posted September 27 Report Posted September 27 That used to be N158MP which was one of the few Liquid Rockets (LTSIO-550) converted by Darwin Conrad.
Hank Posted September 27 Report Posted September 27 Sad to read this! Doesn't look like much of a runway--is the "substantial damage" due to gear collapsing or being ripped away? Only one good photo in the article, but I don't see the huge cooling air exit hole in the fuselage. Then again, I've only ever seen one Liquid Rocket in person, photo below for comparison. I remember the hole being much larger than it looks, more like a basketball hoop. Accident aircraft: Liquid Rocket reference: Right below the "W", should be close to the "L" in the accident plane, unless it was converted to something else?
1980Mooney Posted September 27 Report Posted September 27 (edited) Here is how used to look before it was exported. I suspect that it was all removed in an unapproved conversion from the TSIOL-550 to just a IO-550 similar to what Mod Works did or maybe they jury rigged it to a TSIO-550 by removing the liquid cooled jugs .. either way a "South of the Border STC...". It would still have the Rocket Engineering designed engine mount....a real "FrankenMooney". N158MP - 1988 Mooney M20L - For Sale by AircraftMerchants Edited September 27 by 1980Mooney
Red Leader Posted October 27 Report Posted October 27 I have never heard of the "Liquid Rocket" conversion. Can you tell me more about it? 1
Fly Boomer Posted October 27 Report Posted October 27 12 minutes ago, Red Leader said: I have never heard of the "Liquid Rocket" conversion. Can you tell me more about it? I think Rocket Engineering developed a conversion for the failed M20L with Porsche engine. They used a Continental TSIOL-550 that produced well over 300 hp, yielding cruise speeds well over 200 knots. The M20L was liquid cooled from the factory, so replacing the Porsche with the TSIOL-550 wasn't as complicated as it could have been.
LANCECASPER Posted October 27 Report Posted October 27 4 hours ago, Red Leader said: I have never heard of the "Liquid Rocket" conversion. Can you tell me more about it? Search is your friend on Mooney space: https://mooneyspace.com/search/?q="LIQUID ROCKET"&quick=1&updated_after=any&sortby=relevancy
terbang Posted October 30 Report Posted October 30 That’s interesting. When we were in Argentina in 2018, our 252 shared a hanger with this aircraft for a few days. I don’t know what happened in the meantime but it was a Liquid Rocket with the LTSIO550 back then. We didn’t get in contact with the owner, another Argentinian Mooney pilot had arranged the hanger for us. Never before (and not after) had I seen a Liquid Rocket an I was amazed to find on in Argentina!
Shadrach Posted October 30 Report Posted October 30 On 10/26/2025 at 11:02 PM, Fly Boomer said: I think Rocket Engineering developed a conversion for the failed M20L with Porsche engine. They used a Continental TSIOL-550 that produced well over 300 hp, yielding cruise speeds well over 200 knots. The M20L was liquid cooled from the factory, so replacing the Porsche with the TSIOL-550 wasn't as complicated as it could have been. I don’t believe that the M20L was liquid cooled from the factory. The power-plant was the same as the one in the mid 80s Carrera 2, which they offered as a one year lease with the purchase of a new M20L. Porsche did not make a production, liquid cooled, flat six until 1996 when a 2.5L liquid cooled H6 was introduced in the original Boxster. 2
Fly Boomer Posted October 30 Report Posted October 30 49 minutes ago, Shadrach said: I don’t believe that the M20L was liquid cooled from the factory. Well, in spite of my penchant for endless research, I screwed the pooch on this one. Somewhere along the line, I made a bad assumption. Thanks for getting me back on the centerline. 1
Shadrach Posted October 30 Report Posted October 30 4 hours ago, Fly Boomer said: Well, in spite of my penchant for endless research, I screwed the pooch on this one. Somewhere along the line, I made a bad assumption. Thanks for getting me back on the centerline. Easy mistake to make. I’m a bit of a car/Porsche geek so that’s why I caught it. Not trying to be pedantic, I just thought it was relevant to the discussion about the conversion. As far as I know, the TSIOL-550 is the only liquid cooled powerplant ever installed on the M20 airframe and it required some fairly involved modifications.
redbaron1982 Posted October 30 Report Posted October 30 Aside of the 1980's market downturn, that most likely killed the PFM 3200, does anyone have first hand or reliable information on how well (or bad) the engine would perform? I mean performance, maintainability, dispatch rate, etc.
N201MKTurbo Posted October 30 Report Posted October 30 9 minutes ago, redbaron1982 said: Aside of the 1980's market downturn, that most likely killed the PFM 3200, does anyone have first hand or reliable information on how well (or bad) the engine would perform? I mean performance, maintainability, dispatch rate, etc. If my memory serves me, there was no issue with reliability. It was a little underpowered compared to the Brovo. I think Porsche abandoned the project, not Mooney. BTW, I have never flown one. 1
Fly Boomer Posted October 30 Report Posted October 30 1 hour ago, Shadrach said: As far as I know, the TSIOL-550 is the only liquid cooled powerplant ever installed on the M20 airframe and it required some fairly involved modifications. I have tremendous respect for Conrad and his boys -- they have performed some engineering miracles. Only reason I can think of for choosing the TSIOL is that (like the TSIO-520-NB engines on the Rockets), RAM (I think) put them on Cessna 414s, and he already had the crazy 8-point engine mount used on the Rockets. 1
aviatoreb Posted October 31 Report Posted October 31 On 10/26/2025 at 11:02 PM, Fly Boomer said: I think Rocket Engineering developed a conversion for the failed M20L with Porsche engine. They used a Continental TSIOL-550 that produced well over 300 hp, yielding cruise speeds well over 200 knots. The M20L was liquid cooled from the factory, so replacing the Porsche with the TSIOL-550 wasn't as complicated as it could have been. I read somewhere it produced 350hp and was capable of 260kts. And I read they added gussets to the wing to strengthen them for the high speeds. I read there were only 5 liquid rockets ever made. 1
Fly Boomer Posted October 31 Report Posted October 31 10 hours ago, aviatoreb said: I read somewhere it produced 350hp and was capable of 260kts. And I read they added gussets to the wing to strengthen them for the high speeds. I read there were only 5 liquid rockets ever made. All I know is what I read on the Internet -- frequently questionable. I think the 350 hp is right. The top speed, as with many of our airplanes, depends on a lot of factors, but I have no doubt it's well up into the 200s. Also, I read somewhere that there were 30 or so converted, but at the time the article was written, there were only 5 still flying. Whatever the actual numbers, it has to be the fastest Mooney ever. That said, the complexities were many. 1
Pinecone Posted October 31 Report Posted October 31 16 hours ago, N201MKTurbo said: If my memory serves me, there was no issue with reliability. It was a little underpowered compared to the Brovo. I think Porsche abandoned the project, not Mooney. From what I recall from the times and reading various things over the past couple of years, that was the issue. It was OK, but needed some tweaks to make it better (a bit more power) and Porsche bailed. 1
N201MKTurbo Posted October 31 Report Posted October 31 59 minutes ago, Pinecone said: From what I recall from the times and reading various things over the past couple of years, that was the issue. It was OK, but needed some tweaks to make it better (a bit more power) and Porsche bailed. I’m sure Porsche management who was spearheading this project told everybody that they would be selling thousands of engines and all the airplanes in the world would be flying Porsche engines! Five years later they had sold ~15 engines or so and nobody wanted them. So they fired (or promoted) the responsible party and canceled the program. 1
Igor_U Posted October 31 Report Posted October 31 10 minutes ago, N201MKTurbo said: I’m sure Porsche management who was spearheading this project told everybody that they would be selling thousands of engines and all the airplanes in the world would be flying Porsche engines! Five years later they had sold ~15 engines or so and nobody wanted them. So they fired (or promoted) the responsible party and canceled the program. That's pretty much how I remember it too. I never flew behind one but this article on Falco builder website is quite informative: http://www.seqair.com/FalcoBuilderLtrs/BldrLtr0388.pdf 2
skykrawler Posted October 31 Report Posted October 31 Marginally more performance than a K. Porsche didn't want the liability and was paying people to sell them back then engine.
LANCECASPER Posted November 1 Report Posted November 1 12 hours ago, Fly Boomer said: All I know is what I read on the Internet -- frequently questionable. I think the 350 hp is right. The top speed, as with many of our airplanes, depends on a lot of factors, but I have no doubt it's well up into the 200s. Also, I read somewhere that there were 30 or so converted, but at the time the article was written, there were only 5 still flying. Whatever the actual numbers, it has to be the fastest Mooney ever. That said, the complexities were many. If I remember correctly there were three M20Ls converted to Liquid Rockets and two M20Ms, but I could have it reversed (two M20Ls and M20Ms)
Fly Boomer Posted November 1 Report Posted November 1 11 minutes ago, LANCECASPER said: If I remember correctly there were three M20Ls converted to Liquid Rockets and two M20Ms, but I could have it reversed (two M20Ls and M20Ms) It's possible, but if Darwin did all the engineering for that, did all the test flights, did all the paperwork, got the STC, and then sold 3, he lost his shorts on that project.
LANCECASPER Posted November 1 Report Posted November 1 1 hour ago, Fly Boomer said: It's possible, but if Darwin did all the engineering for that, did all the test flights, did all the paperwork, got the STC, and then sold 3, he lost his shorts on that project. Yep. He sold a lot of M20K Rocket conversions and M20J Missile conversions though. The Liquid Rocket was the last Mooney project, then he shifted focus to the JetProp for the Piper Malibu. 1
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