Are the M20C/D's legal to fly under MOSAIC

[ptwffz]

3 minutes ago, Paul Thomas said:

The manufacturer needs to do the testing and I can't see Mooney doing it; maybe they'll be willing to outsource it to you.

I must have missed the setion stating "manufacturer tested."

[PT20J]

34 minutes ago, ptwffz said:

I wish AI would reveal its source. My Owners manual does list VS1 as 67 MPH IAS. Does anyone on the board have a Master manual that shows CAS conversions at that low of an airspeed?

 

AI Overview

 

The

Mooney M20D Master's calibrated stall speed in a clean configuration  is approximately 58 knots (67 MPH). This figure is derived from the indicated airspeed (IAS) and the airspeed calibration information provided in the aircraft's Pilot's Operating Handbook (POH) and related documentation. 

 

 

 

 

Details on the Mooney M20D Stall Speed 

• Indicated Airspeed (IAS): The POH for the M20D Master typically lists the clean stall speed as 67 MPH IAS, which converts to approximately 58 KIAS (Knots Indicated Airspeed).

You cannot use just any old POH. You need the POH/AFM that goes with your specific airplane serial number. Mooney can supply that if you don't have the correct one. However, since your airplane has been modified, any change in limitations caused by the modifications need to be taken into account. If the mods were done by STC, the documentation would have a AFMS that would list any changes to the limitations. It becomes tricky when multiple modifications are applied because of the potential for interactions between them. 

 

[ptwffz]

2 hours ago, PT20J said:

You cannot use just any old POH. You need the POH/AFM that goes with your specific airplane serial number. Mooney can supply that if you don't have the correct one. However, since your airplane has been modified, any change in limitations caused by the modifications need to be taken into account. If the mods were done by STC, the documentation would have a AFMS that would list any changes to the limitations. It becomes tricky when multiple modifications are applied because of the potential for interactions between them. 

 

Understood. When you say "modified" are you referring to the aircraft being modified with retractable gear/ constant speed prop or my airspeed indicator. I'll reach out to Mooney.

[Hank]

1 hour ago, ptwffz said:

Understood. When you say "modified" are you referring to the aircraft being modified with retractable gear/ constant speed prop or my airspeed indicator. I'll reach out to Mooney.

Since the D was designed to be upgraded to constant speed prop and retractable gear using factory parts and instructions, that's not what "modification' generally means, that would be adding various STCs to change the airplane's conformance to the type certificate. 

[PT20J]

7 hours ago, ptwffz said:

Understood. When you say "modified" are you referring to the aircraft being modified with retractable gear/ constant speed prop or my airspeed indicator. I'll reach out to Mooney.

I was thinking of the retractable gear and constant speed prop. 

[ptwffz]

5 minutes ago, PT20J said:

I was thinking of the retractable gear and constant speed prop. 

Gotcha.

 

[PT20J]

5 hours ago, Hank said:

Since the D was designed to be upgraded to constant speed prop and retractable gear using factory parts and instructions, that's not what "modification' generally means, that would be adding various STCs to change the airplane's conformance to the type certificate. 

It is certainly possible to "upgrade" a M20D to a M20C using factory parts. The question becomes one of how that gets done and what you are left with afterwards. Mooney doesn't list a kit to convert these on it's list of retrofit kits. Maybe a kit used to exist. If so, it would have all the appropriate paperwork. If there is no kit then it might be possible to make the change with a field approval which again would include the paperwork. Or maybe someone got an STC. But you have to have some basis of approval - you can't just go switching around parts from a different airplane. If the factory did the mod, theoretically they could reissue a new type certificate. This was done with C-47s after the war when Douglas ran a line converting military aircraft to a new commercial type designation DC-3C.

[Hank]

40 minutes ago, PT20J said:

It is certainly possible to "upgrade" a M20D to a M20C using factory parts. The question becomes one of how that gets done and what you are left with afterwards. Mooney doesn't list a kit to convert these on it's list of retrofit kits. Maybe a kit used to exist. 

Back in the day, D'a were advertised as low cost entry planes with factory upgrades available later. But the D was only in production for a few years (3? 5?), so the kits have not been available for decades.

The last I heard, there were just 3 (three!) D models in original condition, the rest having been upgraded to be similar to a C.

[cliffy]

The factory did supply a conversion kit for retractable gear on the D  Mine has a notation on just that.

The D came out with stiff gear and a wooden fixed pitch prop.

There were around 250 D models (the TCDS has the correct number but I don't have it handy).

IIRC there are only 2 stiff gear Mooneys still in the registry and only one flies.   Again IIRC

Mods that might affect the CAS stall?  Vortex generators BUT the control is "original certification"

not after mods.

It would be a small niche of pilots affected by the MOSAIC rules in a Mooney but for those who would be it would be a big deal

[ptwffz]

1 hour ago, cliffy said:

The factory did supply a conversion kit for retractable gear on the D  Mine has a notation on just that.

The D came out with stiff gear and a wooden fixed pitch prop.

There were around 250 D models (the TCDS has the correct number but I don't have it handy).

IIRC there are only 2 stiff gear Mooneys still in the registry and only one flies.   Again IIRC

Mods that might affect the CAS stall?  Vortex generators BUT the control is "original certification"

not after mods.

It would be a small niche of pilots affected by the MOSAIC rules in a Mooney but for those who would be it would be a big deal

Yes Cliffy. A big deal indeed.