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Mooney Missile with a 4 Blade MT Prop


Seth

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Prop governor and arm

The MT propeller arrived along with the new prop governor. As noted, a big reason I made the change was to remove the failure point of a prop governor malfunction causing potential engine stoppage, complexity, and weight of the full feathering prop. However, this also highlighted the “arrogance” or "dismissive" attitude I had experienced earlier with MT when double checking or pointing out certain potential items.

The MT prop governor was a smaller size than the prop governor in the Missile. 2.5 to 3 inches smaller in length. So the end of the prop governor did not match up at ALL with the prop cable. This was an issue. Pictures will be on the next post which Anthony can properly orient.

A call was made to Larry at Flight Resource LLC, the MT distributor, who said we’d need an arm, and let us know that MT would get it to us. I reminded him this is the first Missile getting an MT prop, and do you need pictures/measurements – it seemed that MT felt they had the data, but I’m not sure how.

About six weeks went by and we received an arm extension from MT from Germany. MT manufactured it specifically for us. Pictures will be on the next slide. It was about correct in length and travel, but the loop for the connection to the prop cable was 180 degrees opposite of where it should be. It was the arm designed for the Rocket, not the Missile.

This is where we realized something. Chris the A&P doing most of the work at Freeway’s MSC said he bet there was an issue with the translation of Missile in German. So I looked it up and he was correct: The German word for Rocket is “Rakete.” The German word for Missile is . . . “Rakete.” Can you image the discussions? This is the Rakete not the Rakete. Send the Rakete arm but for the Rakete not the Rakete. So they sent the Rakete arm.

We sent pictures back with explanations. They engineered and created a new arm/part for us and sent it about a month later. It was close to right but some of the angles were off. We took some measurements, told them what was needed, and a month later on the third engineered arm we got the right part.

So, in the end, this delay took an additional 3.5 months. We were now into October 2020. Concurrently, we had some issues with the engine – I’ll get to that in my next written post after posting some pictures of the prop governor and arm issues.

To be continued . . .

Edited by Seth
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Anthony - not one orientation is correct. Can you please orient so the prop governor is on the left side of the page and the prop cable is on the right side? Some are up side down and some are on their sides.

The pics show first the fact that an arm is needed. And then shows the Rocket arm instead of the arm that we had to have them manufacture for the Missile (I don't have the correct arm pictured . . . just the one for the "Rakete."

 

Thanks!

Edited by Seth
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1 hour ago, Seth said:

Anthony - not one orientation is correct. Can you please orient so the prop governor is on the left side of the page and the prop cable is on the right side? Some are up side down and some are on their sides.

The pics show first the fact that an arm is needed. And then shows the Rocket arm instead of the arm that we had to have them manufacture for the Missile (I don't have the correct arm pictured . . . just the one for the "Rakete."

 

Thanks!

Anthony ( @carusoam ) is only a PP, not a picture orientator (PO), however he does do it as a hobby in his spare time. 

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Anthony you are so good.

As you can see the Rakete (Rocket) Arm was not sent with the Rackete (Missile) prop governor, even though it was needed but not correct for the Rakete (Missile).

-Seth

Edited by Seth
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Wow, and holy cow...

Fortunately,  there isn’t much force transmitted on that arm...

The extra torque generated over the extra few inches wound try to bend things...

 

Go MS!

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  • While hanging out with Mooniacs...


We learn a lot just by being here...

Best regards,

-a-

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Still room for an update..? :)

It looks like the Missile has the forerunner of the pixie hole...

The Ovation is known for adding a hole above the #5 cylinder on the IO550s...

Similar to the blue arrow marked hole here...

The O’s pixie hole is a bit higher than the cylinder... adding more to the pressure above the cylinder...

having the forerunner pixie hole at one height, and the new gov arm not too far below it...

Did that seal get swapped with something a bit tighter?

We have a seal guy around here...   :)

Blocking high pressure air from entering below the cylinder... may improve CHT in that area...

If you have a CHT challenge there...

PP thoughts only, not polymer seal guy....

Hmmmmm... seal / Guy... something sounds familiar... about that...

Best regards,

-a-

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Engine

When the engine arrived, we should have looked more carefully for the STC modified parts to ensure the engine was legally set back correctly. We had no reason to assume it was not, but it’s something worth noting for Rocket and Missile owners – if you send the engine to the factory ensure the STC modifications are documented. Thank goodness we did.

Once installed, we knew we’d have to bend a fuel line to the front left cylinder to deal with the Missile cowling “wink.” However, we soon ran into a larger issue. As noted on Mooneyspace, the throttle body control unit was not the same as the one we that had been sent to Continental.

We showed the pictures and part numbers to Continental and they said they didn’t understand why the part would be different, checked our paperwork, and realized the throttle body control unit had bene swapped for an overhauled unit as opposed to having the STC modified unit overhauled as agreed upon. Thus, they searched for the STC overhauled unit but it was no where to be found.

Part of this was due to the fact that the person I had originally spoken with details wise had been part of the force downsizing/furlough that occurred with COVID (He was back toward the end of the saga). Once Continental realized they made a mistake and sent an overhauled unit that legally wasn’t allowed to be put on the airplane, and realized the FAA violation implications, they recognized the situation and did anything and everything to assist in making it right. A higher up was assigned to quarterback the problem.

They contacted Rocket Engineering, along with us, so that we could have the part shipped there and modifications would be made in order to bring it up to the STC standard. Rocket received the throttle body control unit and sent it back to us with two control arms attached – but didn’t address the main issues which was that one side of the openings had a lip on it instead of being the same as the other side where a hose could be clamped over it. I’ll attach some pictures. This was already about a month after sending the part to Rocket.

To add confusion, we then learned that Continental sometimes does not tell an owner that they are replacing the old throttle body control unit with the new style. We though this may be the issue so we tracked down a shop that overhauls the old units and we got pictures and realized we had the new unit but modified – which did make sense with when Missile conversion occurred – new style modified. So we reached back out to both Continental and Rocket to figure out who made the modifications. It was determined it was Rocket, they realized it after looking at drawings again, and we sent the part back to them a second time (about six weeks after they sent it back to us) and they modified.  It was the first time they modified the throttle body control unit for a Missile in 22 years. They did great work the second time.

In addition, Continental did not know that the elbow joint boots that Rocket specified were the same parts, just slightly different part number, than what they supply, so they did not send them with the overhauled engine. I requested the parts and Continental sent them.

Oh, I forgot to mention, twice during this ordeal the Alabama factory was shut down and evacuated due to hurricanes slamming into the gulf coast. A week would go by each time with no communication. It didn’t matter so much, but it simply dragged the process along with everything else out when it all got added up at the end.

Once we had everything back at W00, Freeway MSC, now in mid-November, the throttle body control unit fit just fine. We then realized all the fittings had been swapped out for a standard setup, not the Missile set up. We were able to swap some around but also had to ask Continental for certain fittings. They sent them, but at this point we were into late November. I lost a bet I’d be flying before Thanksgiving with some buddies.

So, the prop arm was finally hooked up to an engine that finally had all the right STC parts back on it . . . almost.

We’ll talk about the exhaust next.

To be continued . . .

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The modified throttle body control unit has two matching sides - the hoses fit over the connections. The one sent back had a lip on one side for a V clamp which is not the STC design for the Missile.

-Seth

 

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Edited by Seth
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Exhaust

When the prop was being manufactured by MT and the engine was in Mobile Alabama and the Continental factory, we took the already removed exhaust and sent it out for overhaul. We sent the exhaust first to the shop that overhauled it in Minnesota in 2011. As noted earlier, they realized it needed a mold/bend/tool/jig that only Rocket Engineering had and suggested we send it there for the overhaul. We agreed. However, their shipping department sent it to a similarly named company in Texas. It was sent to a shop that had no clue why they received it. We got a phone call stating they had this exhaust system, and were confused. We sorted it out and it was then shipped via Texas to Rocket Engineering in Spokane, Washington. It was a week delay and no harm done with the rest of the delays, but another time suck to figure out why the exhaust wasn’t at Rocket in Washington State and to then get in there.

Rocket Engineering overhauled it and sent it back to us. They were great to deal with, let me know my options on certain areas, overall wear, etc. We had it back before we got the engine back, which was before we got the prop back.

MONTHS later – December 2021 – we finally were able to install the exaust on the airplane, however we ran into an issue. One of the pipes seemed as if it was the wrong length and thus wouldn’t fit back together properly. When we looked at pictures of what was sent and what came back, we realized the part/pipe had been overhauled/replaced at a slightly longer length. Again, this is the second time during this process an FAA authorized repair center had sent an overhauled part that was not in compliance to the end user (first Continental, now Rocket). It took some time to get back in touch with Rocket, as they are on an abbreviated hour format right now only four days a week and sometimes take a few days to return calls. However once in touch are responsive. They asked we send the pipe back and they’ll check it on the jig and modify if needed (which they should have done during the overhaul).

UPS then took a 2nd day air package and delivered it 10 days later, of course during Christmas week at this point. Rocket confirmed the part did not match the jig, took about an inch or so off it and then expanded the pipe appropriately at that point. It shipped out in early January and we got it a week later – it fit perfectly. This was the second time with Rocket during this project that a part was sent in, was sent back, and then had to be sent back again. They in the end got it right and did good work, but it’s worth noting the being sent twice on two different items.

We also had an issue with a part that held the exhaust probe in place but I was able to get one from a distributor in early January.

So, I lost another bet at this point that we were into 2021. Everything was coming together. The engine was assembled, and it was time to start the engine and properly set it up for the test flight. We were into the second week of January 2021. We were so close. I had blocked off a few dates around January 15th for the first test flight – weather looked good.

To be continued . . .

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On 3/25/2021 at 12:49 PM, M016576 said:

Seth- you’ve got me on the edge of my seat!  I can’t wait to hear how it flies!!!

Sorry - Let me get working on the next installment - And yes, she's flying - just got my IFR certs completed this past Monday. So I'll hopefully fly "in the system" sometime soon. We'll complete the first oil change soon as well.

-Seth

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2 hours ago, Seth said:

Sorry - Let me get working on the next installment - And yes, she's flying - just got my IFR certs completed this past Monday. So I'll hopefully fly "in the system" sometime soon. We'll complete the first oil change soon as well.

-Seth

You have a future as a serial writer.

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Prop Setup:

It was time to properly set up the engine. The instructions from Continental though standard were vague. We got in touch with Continental to find out exactly what they had done at the factory so we would put no more additional time on the engine getting it set up. The prop was on, the checks were made, she came to life, everything was looking good . . . except . . . the prop would not go past about 2550 RPM static. It needed to be 2650 RPM static on the ground run.

So, we contacted MT. Larry of Flight Resource was my main contact at this point and he told us to make changes to the prop governor which we did. We still could not get the prop to spin up to the correct RPM. One of the projects at the MSC a while back was a 182 (yes, they work on other airplanes too, including the flight school at Freeway) with a new prop and IO550 - and the STC prop was set up wrong from the factory blade angle wise. It turns out this was the problem here as well. I’m not sure if this was a Rackete (Rocket) vs Rackete (Missile) thing or just an oversight, but after conferring with Larry again we adjusted the blade angle on the prop itself, and achieved the required static thrust.

We then double checked paperwork at that point preparing for the first flight (mid-January) to find that in the STC documents, which we should have checked carefully earlier (we did go over them to an extent), unfortunately had a typo. The engine in the propeller STC paperwork was incorrect. So, we reached out to Larry at MT/Fight Resource again and found that his copy had the correct engine listed. But the one in our hand was the wrong engine listed. We have an IO550A in the Missile, not an IO550M as was indicated on the paperwork. Larry said he’d send new paperwork. However, due to the relationship with the FSDO he used, he’s not allowed to fax or email paperwork, it has to be sent via mail. He said he’d get it in the mail that day – which was the 15th or 16thth of January. We all know where this is going. Post office mail delays.

The paperwork arrived January 26th. By that point, we had a string of not great weather and were days from February. We decided to wait until February to complete sign offs as that would give an extra “month” until the next annual window wise if needed, and we had to wait for a good weather day anyway. What’s 5 more days after 18 months?

First flight . . . to be continued . . .

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First flight!

On Thursday, February 6, 2021, N1165N flew for the first time in 18 months. It had a newly overhauled engine, and a new 4 blade propeller. This was an important flight as it was both a break in flight and we had to watch the propeller to ensure the RPM’s did not overspeed due to all the adjustments made. We also watched to ensure fuel flow was high enough for the Mooney Missile to properly cool the engine on takeoff (known Missile issue).

Static thrust was at 2640 on the ground as per the notes from the engine setup after physical propeller blade angle correction (which was supposed to be 2650 and okay). The max red line RPM is 2700. In retrospect, I’ve learned that the fourth blade may change the dynamics of a 50 RPM increase in motion, but I’m not sure why from a computational standpoint, or we’d see the same issue in 3 vs 2 blades which are common. Also, it is a slightly shorter propeller at 74 vs 75 inches diameter – which again, should change sound harmonics, as the tips is not moving as fast, but the RPM should be constant due to the prop governor. To say the least, there were unknowns with the propeller.

In addition, during the final and flare, I’ve flown the 4 blade MT on some of the SR22T aircraft, and it acts as a giant air brake at low power prop forward. So, when flaring the Cirrus with a 4 blade tend to sit immediately when you pull power. I know the Mooney is less draggy design so I was curious how it would perform in flare.

The CG was moved back just over an inch due to the 26 lbs coming off the nose, so I also was curious how that would change the heavy nose/pitch feel of the Missile – Erik has been very happy with it in his Rocket (Rakete!).

I brought along one of the instructors with me at Freeway as he owns a Mooney (M20C) but also has time in mid and long body Mooney’s. I wanted him on board for the first flight or two so that if anything occurred, I’d have assistance. Also, when flying, I wanted some one really watching the temps, fuel flow, gauges, etc. I created a checklist and data sheet for him to complete so every 5 minutes we’d be writing down engine information (I can pull it later from my JPI 830, but I figured this way I could quickly see trends in temps during the flight).

We had an additional issue with the initial flight – W00 is located inside the Washington, DC SFRA (Special Flight Rules Area) and also under a 1,500 foot shelf of class Bravo. While most BRAVO airspace allows VFR aircraft to fly at 200 knots below the class Bravo, in the SFRA VFR aircraft my not fly faster than 180 kias. The Missile at full power down low is faster than 180 kias.

Instead of contacting the Baltimore FSDO, my plan was this:

Take off, orbit the field at 1,300 feet (1,500 foot class bravo) 2-3 times to ensure everything was okay. Then fly to the 2,500 shelf toward Annapolis (ANP) and then across the Chesapeake Bay (3,500 shelf)  to leave the SFRA toward Bay Bridge Airport (W29). Then turn south to Easton, MD, a towered airport, and orbit there for about 40 minutes before reversing my route and coming back to Freeway (W00). Time between airports were minimal and we were in glide distance of Baby Bridge airport or land while crossing the Chesapeake Bay.

The time came for takeoff:

During the takeoff roll the RPM went and passed 2700, 2710, 2730, 2780 . . . I started pulling back on the prop and got it to around 2650 when we rotated. Everything else was fine. Larry from MT/Flight Resource and Chris from Freeway MSC both specifically instructed me to watch out for prop overspeed. Fuel flew was fine. All temps were fine, all indications were fine. Afterward, I learned a 10% error was fine. Anything over that and the entire engine would have to be shipped back to Continental for a rebuild.

After two trips in the pattern, we were fine. I had to pull back on manifold pressure to keep us under 180kias. I dialed back to 2500 RPM. We then started our trip. During the shallow climb I gave full MP. When level until outside the SFRA I had to pull back on MP. Once outside the SFRA, MP was WOT until it was time to renter at the end of the flight. We climbed to just under 3,000 feet. I had talked to the Easton (ESN) tower the day prior and as we approached check to make sure it was okay to orbit in their airspace and it was. Four way GPS speed runs in the Easton tower at WOT and 2500 RPM around 2,500 feet was 186 knots. In future flights I’ve been faster – we’ll get into that later.

On the return to W00 I had to pull some MP in a shallow dive to stay under 180kias. Prior to entering the SFRA I was well over 180kias – actually close to VNE. We descended to about 2,000  I didn’t pull power significantly to enter the pattern until close to W00. I climbed and turned to sluff off speed to lower the gear and then get the flaps in. I then added power back. The landing was as if I hadn’t missed a day flying my Mooney. The flare was indeed shorter due to the propeller acting as a brake. The “play” I had in my pitch zone was much better than then window I used to operate in due to the lighter nose. Still a heavier overall airplane, but much closer to a J in pitch vs the former Missile setup (still not as light as a C/E).

We did not go for a second flight as we wanted to de cowl, look for oil leaks, and most importantly, figure out why the propeller overspeed occurred and adjust. So the decision was made for me to come back Saturday after the prop was corrected. The decision was made to adjust the governor back to exactly where it had been set but not touch the prop blade angles.

To be continued . . .

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Just as I was ready to do some binge reading... :)

Break in flights are the most magical!

Low, over the ground...

lower, over water...

High power, changing RPM on a schedule...

During the transition from 2k’agl to 1k’agl... you probably bump the Vne... in an easy descent...

+1 for bringing an SIC/extra pair of eyes... so much going on when things are going as expected...

 

Seth,

What was the max FF you could get?

What is Vne on the Missile?

Best regards,

-a-

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VNE is typical M20J - 198 KIAS. 

FF at takeoff for the Missile is 28GPH min if you don't want cooked cylinders. 

FF in cruise ROP full rich at high power settings during break in was easily 20GPH +

FF will be back to LOP in the 12-14 range for 170 to 180 True and 185-192 15 to 18 ROP depending on altitude.

I have not had her over 4,000 feet yet and only have about 11 hours on her right now. Oil burn/useage has stabilized. I'll conduct my first oil change soon. 

On my next flight I'll do a LOP test to ensure the GAMI's are set up right and then send the info to GAMI for them to review. If needed we'll make an adjustment which is a 50/50 proposition evidently. We cleaned the Gamijectors and reinstalled them in place of the factory injectors.

 

-Seth

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Great report Seth! So happy to hear of your Missile's return to the skies.

Steve

Edited by ohdub
You answered my question - posting at the same moment that I did :)
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  • 2 weeks later...

Great thread.  Thinking about flying our Rocket to OSH this year.  After watching arrival videos what worried me the most was tower getting planes to veer into the grass right off the runway.  I guess you could do an 'unable...need a taxiway'... But depending on the taxi length to the tie down area and potential mud conditions...lots to think about...

Edited by Austin305Rocket
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9 hours ago, Austin305Rocket said:

 I guess you could do an 'unable...need a taxiway'

That only works if you have a reservation to park on the ramp at the FBO. And the truth is the taxiways are all on the grass.

Taxiing in the grass is just the way it is at Oshkosh. Generally the Marshals are pretty good at keeping airplanes on firmer ground. I'm sure they don't pay out a lot of these insurance claims every year. But obviously $*!t happens.

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