Moondoggy

Mooniacs, Thank you for your comments and participation in this thread! Your contributions were informative, and a consensus has emerged that provides an answer to the question posed at the beginning. In sum, pilots may serve as pilot in command of Mooney M-20s while exercising Sport Pilot privileges under the new MOSAIC final rule, provided the airplane's originally certificated maximum takeoff gross weight doesn't exceed 2,740LBS. -Cheers

Toto, Sorry for my formal writing style. It’s a habit of writing academically and for the military over the last 35 years. My day job requires precision communication in all forms. Also, my team would rib me for any grammatical errors I present to them in written form. Integrity first, so plagiarizing an AI bot’s product is poor form. My wife sometimes tells me I am exhosting to talk to because a thesaurus is required to know what I am saying. It’s hard to turn off TangoTango, The devil is in the details, you could interpret, “Since its original certification” to mean exactly that and then allow Sport Pilots to operate an airplane that doesn't have a VS1 of 59 KCAS when loaded above 2740 LBS. But I feel that the intent of the final rule is to reduce the kinetic effect to people and property on the ground should a, less trained/experienced or unhealthy, Sport Pilot crash on takeoff. I believe pages 109, 232, 236, 263, 264, and 684 of the final rule clarifies the FAA’s intent for the speed limitation which drives the takeoff weight for a given airfoil down. -Cheers

1980Mooney, You are absolutely correct! Weight and balance is covered by the SB M20-252 service kit and would also be reverted back to the pre-SB condition. -Cheers

Toto, The airspeed correction chart is the key to properly determining if an airplane meets the requirements to exercise Sport Pilot privileges. Thanks for uploading the chart image; not all POHs have it. Hank, The Mooney 2900LB MTGW increase is at the pilot's discretion as stated in SB M20-252. So, an A&P can, at the request of the pilot/owner, remove the retrofit kit installed in accordance with SB M20-252. Doing this would effectively return the airplane to conformity with the original type certificate and weight limitation. Whether the aircraft is equipped with a steam gauge or glass ADAHRS, the airspeed markings/ranges will need to be regressed to the original limits, the POH supplement will need to be removed, and a logbook entry should be all that is required to allow a Sport Pilot to operate a M20J with a 2740LB MTGW . -Cheers

A64Pilot, I agree that flight testing is not always cut and dry! As a test engineer for modifications made to USAF C-20H and C-37 aircraft, I found it apparent that each aircraft tested had variances from the computed/expected limitations. Barring unexplained deviations from the mean data, we would set the limitation tipping more to the safe side of the envelope we were testing. The M20 TCDS (2A3) doesn't publish the VS1 for any model. Therefore, the MOSAIC final rule, which recommends using AC90-89A to determine VS1, may be used to determine the clean stall of specific models. My experience tells me that weight will be the key factor impacting VS1 if the airfoil is not altered. There are differences in the wing design over the years. Besides the wingtip fairings, which in my opinion have a limited effect on slow flight, specific year ranges of M20s incorporate more washout into the wing. Those years all have an MTGW under 2740LBS. The FAA definition implies that the published lower limit of the green arc is VS1, which I would use to determine the clean stall speed. To determine the application of the Sport Pilot limitation, we need only adjust the published KIAS range to a KCAS range. 1980Mooney, The folks I was referring to had no psychological issues prior to being told they could no longer exercise their pilot privileges. The loss of identity when this happens can be devastating to a lifelong pilot. - Cheers

Refer to the attached 1996 M20J POH Stall Speed Chart for VS1 (Clean Stall) speeds at 2900 lbs, 2740 lbs, 2500 lbs, and 2300 lbs, respectively. Mooney M20J POH Stall Speed Chart.pdf

mhrivnak & 1980mooney, The Sport Pilot speed limitation is 59 KCAS, not 59 KIAS. In my experience as a Flight Engineer, the difference between KCAS and KIAS on the four jets I flew was two knots at sea-level standard day temperature and zero humidity. That said, 59 KCAS is equivalent to 61 KIAS. This is why, in my 1965 M20E, the bottom of the green arc (VS1) is 70 MPH (indicated) or 68 MPH (calibrated), which, when converted to Knots, corresponds to 61 KIAS and 59 KCAS, respectively. TangoTango, I agree with you, many people have been unable to obtain a license to fly legally due to medical conditions that are, frankly, benign and yet prevent them from legally operating an airplane. Now, they won't be criminals if they want to pursue their passion for flying. Also, I have had many friends who have suffered deep depression, and some have decided to leave us early because they could not fly due to medical conditions (very sad).

Thank you, Toto! The discussion thread Mosaic Mooneys is great.

Mooney Flyers, I seek consensus and feedback from Mooney operators regarding the new FAA rule change (MOSAIC) that allows Sport Pilots to fly four-seat complex aircraft, provided the aircraft’s clean stall speed is 59 KCAS or less. Are Sport Pilots allowed to fly the M20 with the MOSAIC final rule? Using the TCDS, Owners Manuals/Pilot Operating Handbooks (POH), FAA definitions, and the final rule as a reference, it looks like the answer is not no. The answer is more like, “It depends!” Because we are dealing with a stall speed limitation (VS) and VS is measured using Calibrated Air Speed (CAS), we must determine how to adjust the indicated speeds published in most Owners Manuals (vintage Mooneys) and POH (later Mooneys). The aerodynamic design factors that impact the stall characteristics of the M-20 have not changed substantially from the original type certificate. Structural enhancements over time have increased the load factors that newer aircraft can be exposed to, resulting in increased speed and gross weight limits. Aircraft maximum takeoff gross weight (MTGW) directly impacts the published clean stall speed (VS1). Therefore, VS1 for the Mooney M20 is a function of MTGW, and the highest published MTGW, which equates to a VS1 of 59 KCAS, is 2740 LBS. So, my position is that a Sport Pilot would be entitled to operate an M20J or earlier with a published MTGW of 2740 or less. The data to support this idea is published in the 1977 Mooney M20J POH Figure 2-2. Published airspeed indicator marking ranges in Figure 2-2 are in CAS MPH. Specifically, the green arc range is 68 - 200 CAS MPH. When 68 MPH CAS is converted to KCAS, the result is 59 KCAS, the limit that Sport Pilots can operate. Why is this important? Sport Pilots only need a valid driver's license to meet the medical requirements to fly; the lack of a flight physical is no longer a limitation to being legal to fly an older Mooney and many other certificated aircraft. Is my position correct? - Cheers