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Posted

The Rocket Engineering Rocket & Missile conversions have been around for a while. My Missile has been my main ride since coming into my possession ~2003. This thread to me has 2 main objectives: 1. Try to get a feel for how many Missiles & Rockets are still active in the Mooney fleet. 2. Share experience regarding maintaining these planes, particularly on aspects unique to the conversions. Additionally, this string might be a good resource for those considering new ownership of one of these on those rare occasions where they reappear on the market.

So...any with experiences owning/maintaining one of these?

  • Like 1
Posted (edited)

I joined a Rocket partnership last year. Maintenance has been very expensive this year. We've had to repair the engine frame and replace the exhaust. Rocket Engineering still supports the conversions and parts are still available, but they're made to order. We also had to rebuild the turbo. This wasn't done by Rocket Engineering since it's also found on the Cessna 414, but it is specific to the conversion. This was all around 1000 hours SMOH.  I'm very glad expenses are split multiple ways.

The other maintenance items were general Mooney or airplane items and not specific to the conversion. For the most part, it's still an M20K. Your A&P might complain about working on it, but they won't turn you away.

Edited by louisut
Posted

I purchased a Rocket Engineering Missile conversion in 2019.  I have a thread in Modern titled “Missile Coming Out Party” that describes maintenance and areas of emphasis in the year we have owned/updated our plane.  The conversion was to a 1980 M20J.  There are fewer than 60 total conversions.  One Missile was lost last December when a pilot in NY apparently ran the plane out of fuel and crashed on short final.

We LOVE our Missile.  An engine overhaul will be needed “soon” for our plane.  We have no known “issues” at this time after a lot of sorting in the last year.

Posted

Maintenance areas of emphasis on Missile we have identified:

1. Exhaust system wear/replacement.  The exhaust is custom.  Rocket has and sells replacement sections that an area shop can weld/fabricate.  A custom shop may be able to copy/duplicate for less expense.  The exhaust tends to wear prematurely.  Needs inspected to include mounts/fittings.

2. Engine Mount wear/corrosion/sagging.  Custom to Missile.  Heat shrouds important to protect from exhaust.  Inspect and maintain.

3. Cylinder premature wear.  Plane is tightly cowled and has no cowl flaps.  Cylinders temps in climb on hot summer days must be monitored.  Increasing speed/lowering nose as in a cruise climb STILL sees very adequate climb performance and covering ground in climb.  Seeing cylinder (s) approaching 400 in climb is NOT uncommon and DOES likely result in cylinder longevity impact.  LOP operations in cruise see VERY manageable cylinder temps at or below 350.

I know of no other maintenance issues unique to the Missile in ownership to date.

  • Like 1
Posted

Condensed from the other topic on converting J to Missile:

Converted my J to a Missile 20 years ago.  It is a 1980 model so it required wing tips per mod.  Added one piece belly for speed and convenience.  Twin Aspens, 530W/430W stack, WX500, GDL88, Flightstream 210, Century 41.  Added Monroy long-range tanks due to thirst. 

As said by others the Missile is tightly cowled without cowl flaps.  On hot Texas or NM summer days, esp. if at large/busy towered airport, have a long taxi or extended hold for IFR  release I might experience high oil temp on ground and high cylinder temps on take off. I used to fret about it while holding but there isn't a lot you can do other than aggressive leaning on the ground.  I simply expedite TO as much as quickly as possible and once airborne I just lower the nose a bit, gain speed and sometimes reduce power a tad to get oil and cylinder temps under control.  In 20 years I have replaced one cylinder due to a valve and one due to compression/oil consumption.   

The IO550A is simple, rugged and thirsty.  I like the Altitude Compensating Fuel Pump (some here don't).  As long as temperatures are in line I take off and climb wide open firewall forward Throttle/Prop/Mixture all the way to assigned altitude (KISS -Keep It Simple Stupid "Set and Forget").  At altitude I typically cruise at 2,400 RPM and then lean 75 degrees ROP.  The standard Cont. injectors are well balanced w/ temps even.  The starter adapter on the IO550 can be a problem but that is a Continental problem (not Missile specific).

As I said previously I haven't found the need for speed brakes on the Missile.  I can dirty up the Missile quickly, chopping power, pitching up, dropping gear and partial flaps.  The gear mechanism is stout and for over 2 decades has always been reliable for the task.  The IO550 is just fine if I pull throttle quickly.- Twenty years is a pretty good indicator although i am sure some here will disagree.

You will not want to land on grass, gravel or dirt.  The prop clearance is a weak point.  The 3 blade Hartzell Scimitar is 75 inches vs the stock McCauley at 74 inches.  You may think one (1) inch is immaterial but with the added weight of the IO550 and prop hanging farther out on the same 3 Lord Discs you get greater oscillation on rough surfaces or a poor landing.   If you are on soft ground the nose gear will sink in due to the additional weight of the 550 and 3 blade prop.  I can tell you from experience that one person cannot move the plane if that happens.  There are several threads on MS of Missile owners refusing to park on grass or wrecking a prop on dirt/grass-Seth, Aug '19 destroyed prop in mud at OSK, FloridaMan, Apr '19 refused to park in grass at Sun n Fun.  The full feathering Hartzell PHC-C3YF-2UF is great but rare.  If you need parts, Hartzell may need to manufacture.  This year I needed the lower half of the spinner (essentially a glorified aluminum salad bowl with a hole in the middle).  It cost $2,000 and I had to wait 6 weeks for it to be manufactured.  The full spinner 2 piece cone with brackets is $4,000 (none were available nationwide either at the time).

The Rocket Eng exhaust is a weak point.  It suffers from corrosion.  I know one owner from Houston who lost the tail pipe in flight.  My A&P found one shop that can repair/fab the exhaust and the product is better than Rocket.  

The greater weight and flex can lead to more fuel tank leakage.  I fight that issue from time to time.

  • Like 3
Posted

One Missile question came up recently... regarding fuel flow..

The STC for some IO550s may be different than others...

 

Basic question, related full power CHTs...

What fuel flow do you see at Sea Level during your initial T/O roll and climb?

There are some discussions amongst the O3 powered crowd of 29-30gph, at WOT, 2700rpm... which may be slightly higher than documented...

 

What do you see? Have you had any difficulty turning up the FF to improve CHTs/cooling...

PP thoughts only, not a mechanic... the FF recommendation came from an article about the M20S Screamin’ Eagle...

Best regards,

-a-

  • Like 1
Posted
11 hours ago, carusoam said:

One Missile question came up recently... regarding fuel flow..

The STC for some IO550s may be different than others...

 

Basic question, related full power CHTs...

What fuel flow do you see at Sea Level during your initial T/O roll and climb?

There are some discussions amongst the O3 powered crowd of 29-30gph, at WOT, 2700rpm... which may be slightly higher than documented...

 

What do you see? Have you had any difficulty turning up the FF to improve CHTs/cooling...

PP thoughts only, not a mechanic... the FF recommendation came from an article about the M20S Screamin’ Eagle...

Best regards,

-a-

I would be interested to hear take off full power fuel flows for sure.  We had an induction leak (rip on gasket was VERY tough to see at first annual...now sorted) that contributed more to adjustment on engine and issue with engine stalling if not at full rich on ground...We were and ARE seeing only 26.5gph on full power at 850ish elevation.  The adjustment (per A&P) is at full stop so there is NO MORE FUEL FLOW TO BE HAD with current equipment.  Last flight with cooler temps showing 1500fpm initial climb at 135knots had only one cylinder (#2) topping 400 (403) indicated on JPI.  #2 has ALWAYS been higher and may be probe position?  Quick climb to 7500 with 1000fpm still indicated at 135knots.  Immediate drop with cruise setting on ALL cylinder temps including #2...

  • Like 1
Posted

I've owned my Rocket for about 18 months.  I had a Maxwell prebuy on a very good airplane and replaced all the avionics.  Since I bought it the only maintenance "issues" have been a leaking left brake, an adjustment of the Air inlet filter box (had backed off the inlet and was not sealed leading to the engine breathing cowling air...diagnosed by higher than normal CDT), and minor tweaks to the idle and full power mixture. That and my #5 runs about 20 degrees hotter than I'd like and we keep fooling with that to cool it down, but that's tomget it down around 360, I can keep it at 380 pretty easy albeit with a bit more gas than I'd like.

0 squawks at first annual at AGL Aviation in May.

At full power on takeoff I get about 34.5 gph, 37.5 MAP and 2650 rpm.  Rocket recommended FF is 33 but Savvy suggested a touch higher for climb cooling.

I normally cruise at 65% at any altitude, 30", 2200 rpm, 1500 TIT, 18.7 gph about 100 ROP. That gets me 197-200 KTAS between 14,000 and 16,000 MSL. Around 9,000 185 KTAS.

I can run LOP at 55%, 26 MAP, 2200 rpm, 1575 TIT, 11 GPH and do 163 KTAS AT 5,000 MSL....almost J "efficiency" if I don't mind going slow.

  • Like 6
Posted
1 hour ago, PJClark said:

I'll add: I hate going slow.  That J-like deal was an experiment.  I go fast.  Its a Rocket :D!

Why go Slow, When riding a Rocket feels so good!!!....:)
 

  • Like 2
  • Haha 1
Posted

I had my 1983 J converted in 2000, standard tanks, vacuum speed brakes mostly original panel. - everything else aside, the thing I have to watch out for is the forward CG limit. I have experienced the same issues as noted above for exhaust and engine mount. Pulled one cylinder at about 350hrs. This may have been related to thermal cycling as I did my instrument rating in it shortly after 9/11. Until August this year I had always run 75 ROP - now have GAMIs and am running at 50-75 LOP and seeing cooler cyl temps. In October I took my son to visit ERAU Prescott. I had him ride in the back to keep in cg envelope with full fuel. Temps pretty even now with GAMIs, but cyl. #1 and #2 egt's about 80 deg. cooler than others. I think this is just from the induction setup of the IO550A. At 8500 to 10500 ft, flowing around 11-12 GPH, EGT 1430-1510, CYL 330-360 deg, WOT, 2350 RPM, 165-170KTAS. The 550 and the 3 blade makes for a very smooth running powerplant. For SL full power take-off FF is 29+ GPH. The climb is great in the Missile - I reduce power to 25" and 2550 RPM during climb I add in MP to keep at 25 - I have to lean a bit to keep engine smooth flow in low 20 gphs- about 1300-1350 egts keeps cyl around 380 target temp at 120KTS. I have always suspected my setup is on the rich side, and did a climb to 14k and data confirms I am above the IO550 flow corridor for the alt comp fuel pump- hence the need to lean a little. Once I do initial leaning on climb, I am set until cruise. In winter I have noticed oil temps on the cool side, and being in Seattle area I have not experienced the hot issues on the ground but lean aggressively for ground ops.

  • Like 2
Posted
1 hour ago, N56394 said:

I had my 1983 J converted in 2000, standard tanks, vacuum speed brakes mostly original panel. - everything else aside, the thing I have to watch out for is the forward CG limit. I have experienced the same issues as noted above for exhaust and engine mount. Pulled one cylinder at about 350hrs. This may have been related to thermal cycling as I did my instrument rating in it shortly after 9/11. Until August this year I had always run 75 ROP - now have GAMIs and am running at 50-75 LOP and seeing cooler cyl temps. In October I took my son to visit ERAU Prescott. I had him ride in the back to keep in cg envelope with full fuel. Temps pretty even now with GAMIs, but cyl. #1 and #2 egt's about 80 deg. cooler than others. I think this is just from the induction setup of the IO550A. At 8500 to 10500 ft, flowing around 11-12 GPH, EGT 1430-1510, CYL 330-360 deg, WOT, 2350 RPM, 165-170KTAS. The 550 and the 3 blade makes for a very smooth running powerplant. For SL full power take-off FF is 29+ GPH. The climb is great in the Missile - I reduce power to 25" and 2550 RPM during climb I add in MP to keep at 25 - I have to lean a bit to keep engine smooth flow in low 20 gphs- about 1300-1350 egts keeps cyl around 380 target temp at 120KTS. I have always suspected my setup is on the rich side, and did a climb to 14k and data confirms I am above the IO550 flow corridor for the alt comp fuel pump- hence the need to lean a little. Once I do initial leaning on climb, I am set until cruise. In winter I have noticed oil temps on the cool side, and being in Seattle area I have not experienced the hot issues on the ground but lean aggressively for ground ops.

I don’t see your fuel flow. I am 26.5 max. I cruise lop, but at 2500rpm. Burning a gallon more, but seeing better speed. I don’t have cg issues. Here is common load using weight and balance pro ap...

216438A5-ACB6-4CC2-ADB2-282E528FC4E6.png

6697C756-6E76-4427-ADD6-4F435F9CC583.png

17E31544-4255-4906-88AE-148C5C5E0205.png

  • 2 months later...
Posted

New missile owner #24-0953

this is a great group I wonder if i could get some basic information?

like a good POH mine is whippy

weight and balance? I see a foreflight entry above mine.

is it possible to copy the foreflight W&B file and transfer it to my ipad?

Thanks for anything

John

  • Like 1
Posted

Welcome aboard John...

The best way to get a good copy of your ship’s POH... is by contacting Mooney.

Your local MSC does the footwork... So calling your MSC to get it organized works...

If you don’t have a local MSC...  Call Dan at Lasar...


You have a Missile STC from Rocket Engineering... you can get a copy from them... expect all the performance data updates to be found there...

 

As for contacting the MSer above...  he has been offline for a couple of weeks...  He has been a great resource on Missile details...  as he is a new owner as well...

PP thoughts only, not a CFI or mechanic...

Best regards,

-a-

  • 2 weeks later...
Posted

Hello! Our company has owned a Rocket for 2.5 years now (N305RM).  Since the initial shakedown maintenance has been very reasonable.  We have put around 1000 hours on her in those 2.5 years, and there is no better tool for business/pleasure in the piston world.  Some key notes:

1) Exhaust needs inspected, and does wear out every 800 - 1200 hours.  We just redid ours at the last annual.  Takes a while to get fabricated and shipped but it's fully supported.

2) Turbos tend to wear out at around 1000 hours, I've reviewed the logs in ours and just replaced our first one at last annual as well.  

3) Customer engine mount, but no issues surrounding that. 

4) Cowl flaps, for us at least, have kept cylinder head temps in the mid 300s, seems to be cooler than some other but I have been blow away by this.  JPI individual CHTs match well with the aggregate original CHT gauge.  They do vibrate though, and we've had them rebuilt once.  Tightened things up significantly.

Don't hesitate to call or email, I'll be happy to show you actual invoices from our prop and mx shop.  

Anthony S. Pentz II

330.904.5066

anthony.pentz@foxtrotaviation.com

  • Like 1
Posted
On 1/28/2021 at 2:34 PM, missile said:

New missile owner #24-0953

this is a great group I wonder if i could get some basic information?

like a good POH mine is whippy

weight and balance? I see a foreflight entry above mine.

is it possible to copy the foreflight W&B file and transfer it to my ipad?

Thanks for anything

John

Your plane is a 1980 M20J.  You should have the basic M20J POH that originally covered the 1979-1980 models. 

Mooney Model Chronology (mooneyevents.com)

For the Missile conversion Rocket Engineering makes no changes to the basic POH but adds a 12 page supplement in Section IX - Supplemental Data.  That supplement has charts - Figure 6.1 - Center of Gravity Weight Envelope and Figure 6.2 - Center of Gravity -Moment Envelope.  There should be an actual current measured W&B in Section VI.

In Section IX you will find all the other Supplements related to your specific equipment  - long range tanks, autopilot, GPS Nav/Com, etc.

  • Like 1
Posted
37 minutes ago, carusoam said:

Welcome out in the open, other Anthony!

:)
 

Fantastic details!

Thanks for sharing them...

Best regards,

-a-

How do you know that he’s not “original Anthony” and you are really “other Anthony”?

  • Haha 1
Posted
31 minutes ago, aviatoreb said:

How do you know that he’s not “original Anthony” and you are really “other Anthony”?

It’s clearly a view point issue... :)

I am the other Anthony... to all the other Anthonys on the planet...

Or is that Anthonies..?

I went to check to see when Anthony first logged in... and saw the pic of a rocket with a fuzzy memorable paint job...

I like the new pi-paint much better... :)

Best regards,

-a-

 

Posted
43 minutes ago, carusoam said:

It’s clearly a view point issue... :)

I am the other Anthony... to all the other Anthonys on the planet...

Or is that Anthonies..?

I went to check to see when Anthony first logged in... and saw the pic of a rocket with a fuzzy memorable paint job...

I like the new pi-paint much better... :)

Best regards,

-a-

 

It is Anthonee' in the plural form.

We are now discussing the theory of relativity as applied to Anthonyism, and reference frames.

oooh - please do point to that first post.

Yes!  My signature used to be green machine.  For my original green dull paint job.  Thanks!

Posted
On 1/28/2021 at 3:34 PM, missile said:

New missile owner #24-0953

this is a great group I wonder if i could get some basic information?

like a good POH mine is whippy

weight and balance? I see a foreflight entry above mine.

is it possible to copy the foreflight W&B file and transfer it to my ipad?

Thanks for anything

John

That is a weight and balance pro ($5 on apple App Store) ap. Worth it as it is easy to use. 

Posted

EIB1 now has an empty seat that can never be refilled. Hope you had a smooth final flight my silver tongued speaker of truth. You shall be missed. The talent, sadly, was only on loan...

Be in peace with the loaner. We have your back sir. May the golden mic continue to educate, enlighten and deliver the truth. 

  • Haha 1

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