The Mooney M20J is a fast and sleek, four-seater aircraft with retractable landing gear. Here’s all you need to know if you plan on owning one.

Mooney built 11,000 M20 aircraft between 1977 and 1999. With just a 200-horsepower Lycoming IO-360 engine, it has a cruise speed of 201 mph while sipping just 11 gallons per hour. It has a service ceiling of 18,800 feet and endurance of 6 hours, costing under $150,000 for a used aircraft.

As a flight instructor, avgeek and pilot, Mooney aircraft were some of the first aircraft I ever flew. Many of my earliest flying

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Background

The M20J is part of a family of M20 aircraft built by Al Mooney’s company, Mooney Aircraft. The first of the M20 line was introduced in 1977 with its sleek lines and characteristic reverse-sweep vertical fin.

The M20 was built off Mooney’s M18, a single-engine, single-place speed demon that was ostensibly created for returning fighter pilots from the war. They built almost 300 units of that plane and in the process learned a lot about general aviation aircraft aerodynamics and the shapes of what would come next.

Mooney wanted to squeeze every knot out of a drop of fuel, gaining speed and endurance. To do that, he focused on how he could reduce drag. There were almost twenty variants in the M20 line, starting with the M20, then quickly followed by alphabetized extensions like the M20 A, B, and so on, with the J variant among them.

Older models of the Mooney M20 have a considerably loyal following, as evidenced by the existence of the Mooney Flyer magazine, the online publication that works in tandem with the Mooney Aircraft Pilots Association to provide Mooney owners with everything they need, from the latest Mooney news to comparisons between the Mooney M20J and other models and how to access things like factory support.

There are four Mooney M20J sub-variants. The M20J 201, the M20J 201 AT, the M20J 205, and the M20J MSE.

The Mooney M20J 201 and the M20J are identically the same aircraft. In fact, the 20J became known as the 201 in a marketing endeavor. The "201" just was there to indicate the top speed the plane would fly at.

The AT subvariant was designated to the Advanced Trainer. The 205 is exactly the same as the M20J 201 except its top speed was 4 mph faster due to some aerodynamic clean-up in the gear doors.

Arguably the most commercially successful variant of the Mooney M20 family, the M20J served as the basis for many of the later M20 variants, be it directly or indirectly. The M20K was built directly off the M20J’s back, whilst it served as the basis for subsequent variants that were entering service well into the new millennium.

There was also a short lived project known as the Mooney PFM in conjunction with engine and sports car maker Porsche. Despite being a turbocharged version of the M20J and, as its marketing material liked to mention “the flashiest ride in the sky” only 41 models were built and the two companies have since parted ways.

It is equipped with four seats (two front seats, one for the pilot and one for either the student/co-pilot or an extra passenger and two rear seats for passengers) and is perfect for long trips. As it is certified as a normal category airplane, most aerobatic maneuvers are prohibited by the FAA.

As is common with many other aircraft of its size and age, the Mooney M20J is a favorite of small cargo operations, as its two back seats can be removed to make a rather large cargo bay. Total production of the Mooney M20J variant sits at 1634.

Design Philosophy

The Mooney M20J is a perfect example of how advanced study in aerodynamics translates to an aerodynamically clean airframe. From the split airfoil usage where the inboard wing uses a NACA 63-215 airfoil and the outside uses a 64-412 airfoil, to the tapered wing that looks suspiciously like a forward sweep, looking at it closely will bring you to the realization that the aircraft is fast.

The empennage is also a study in efficiency. With vertical and horizontal tails seemingly pointed forward, the leading edges of the horizontal and vertical tail are straight while the taper causes the trailing edge to sweep forward, once again giving it a seeming appearance of having a forward sweep.

With those designs, it is then apparent to see that the quarter chord sweeps forward on both the wing and the horizontal stabilizer. The genius about the tail is that there is no flight and attitude combination which I have tried where there is even a hint of loss of vertical tail authority.

But in today's world of aeronautical engineering where CAD software is easily available, almost anyone can put a wing, fuselage, and empennage together and have it fly straight and level. But the shape of the Mooney M20J came in the wake of WWII.

Computers, much less computational fluid dynamics, were unheard of back then. Designing a plane that was aerodynamically superior to almost everything else was a stroke of genius on the part of Albert and Arthur Mooney. And in the case of the M20J, the fine-tuning of the aerodynamics was done by the infamous LeRoy LoPresti.

The plane is so slippery that most Mooney pilots are intimidated by it. Loads of NTSB reports chronicle stories of pilots letting the plane get too far ahead of them, then ending in an incident or accident.

Even the landing gear was unique. Instead of using oleo struts that were notorious for bottoming out after a frigid night, Mooney used rubber shock disks. You could tell when a Mooney taxied by from the unique sound its rubber disks made as the wheels rolled over bumps and uneven ground.

This model’s landing gear legs are attached directly to the main wing spar, rather than the fuselage (a fact made even more difficult because it was retractable landing gear) whilst the nose gear is mounted to a steel frame welded to the forward fuselage.

As for the control yoke, it did take a while for a pilot to get used to the way they were rigged and balanced, especially because the rudder pedals aren’t as responsive as they are on many other aircraft, but once you get used to it - which just needed an hour of flight time and pattern work - it would be impossible to forget.

The Mooney’s fuselage is a bit of an enigma. While it has a sleek airframe, it does not sacrifice any of the cabin space most pilots and people think it does. Cabin volume, at least in regards to the forward fuselage (where the pilot and passengers sit), is equal to larger, more luxurious airplanes like the Beechcraft Bonanza or Cessna 210 (in fact, there’s actually more room when it comes to a comparison with the latter!).

Unlike many of the earlier and later models, the Mooney 20J does not have the Johnson Bar or manual flaps, which help to improve control and increase stall speed.

As a redundancy, an electric fuel pump has been fitted, which is fully capable of supplying all the pressure and fuel flow needed to maintain control in flight, in case the engine driven pump fails.

Specs

Specification Mooney M20J
Engine Lycoming O-360-A3
Engine HP 200 hp (149 kW)
Rate of Climb 1030 fpm (5.23 m/s)
Service Ceiling 18800 ft (5730 m)
Cruise Speed 175 kn (200 mph; 324 km/h)
Stall Speed 53 kn (61 mph; 98 km/h)
Takeoff Distance 970 ft (296 m)
Landing Distance 800 ft (244 m)
Range 700 nmi (806 mi; 1296 km) plus IFR reserves
Fuel Burn 11 gph
Fuel Capacity 64 gal (291 l)
Useful Load 1050 lbs (476 kg)
Operating Empty Weight (OEW) 1671 lbs (758 kg)
Gross Weight 2740 lbs (1243 kg)
Length 26 ft 9 in (8.15 m)
Wingspan 36 ft 5 in (11.1 m)
Height 8 ft 4 in (2.54 m)

Fuel Burn

For most airplanes, speed, fuel burn, and specs are closely interconnected. To improve one, usually meant having to sacrifice one or both of the remaining. For example, when an aircraft’s mission profile was speed, it will have to burn more fuel, and thus, be less fuel efficient.

The Mooney M20J, however, is different. With 10-12 gallons per hour as its fuel burn and a top cruising speed of 176 knots, it is able to have specs superior to aircraft that use the same Lycoming engine. Now that’s the “Mooney factor” pilots across the world keep talking about!

The same reason it flies at top speed and low burn is the same reason pilots find it difficult to handle. It is inherently unstable from the pilot’s perspective, and it doesn’t want to quit flying. But this is merely the perspective of a pilot who is still a little low on flight time or one who is used to typical flight school trainers that fall out of the sky once the throttle is retarded.

The Mooney is efficient and therefore requires forethought and planning when it comes to managing speed and phases of flight.

Price

Mooney ceased its long production of the M20J in 1999 and has no plans on resurrecting it anytime soon. Those interested in the iconic aircraft will have to be content with picking one up in the used market. A late model M20J, regardless of the sub-variant, averages a price tag between $140,000 and $150,000.

When it comes to a Mooney, however, it's not that simple. For one thing, more than 11,000 units were built, of which under 2,000 were specifically designated as the M20J. But over the years, the models in the alphabet soup that made up the M20 A through K have been subject to numerous upgrades by Mooney enthusiasts that it's hard to tell one from the other, especially for the earlier models.

The other reason that prices for the Mooney are a little nebulous is because of the nature of the aircraft. Many claim to have new paint jobs, new parts, and so on, but are silent on accident history, and there are a lot of those. So, it is a buy-beware market. If it’s too good to be true when it comes to a Mooney, then it most certainly is.

When it comes strictly to an M20J, the price for one between the years 1977 and 1987 will vary between $80,000 on the low end to $180,000 for one that is in super condition.

Of this wide price range for the M20J, you can break them down into three categories.

The first price range is for M20J aircraft with minimal specs. Most of these are not in airworthy condition and present an opportunity for those who have the necessary skills to rebuild the aircraft.

Prices for this kind of opportunity with the M20J range between $80,000 and $140,000 depending on what’s included and what needs to be done. One thing for certain, it's almost certain that the engine is out of time.

The next price range is between $135,000 and $160,000. The main feature lacking in aircraft in this range is the upgraded avionics. Most of the aircraft in this category still have steam gauges that have subsisted since they left the factory in Texas.

The third category of M20Js based on price are those that fall into the range between $160,000 and $190,000. While there are some outliers that may breach the $200,000 mark, they are not the norm.

Mooneys in this price range typically are in mint condition, with upgraded avionics, perfect records, low time, and a pristine paint job.

Direct Operating Cost

DOC for short, Direct Operating Cost refers to everything that you will need to pay for, out of pocket, each time you use the aircraft.

Most of these are easy to calculate once you know the logic and reasoning behind the why and the how. The main direct operating cost of the Mooney M20J, and this is true for all aircraft, is the cost of fuel.

The M20J has a low fuel burn and so its DOC is generally lower. At an average of 11 gallons per hour and an average price of $7 per gallon of AvGas, the first component of DOC is $77 per hour.

The second component is oil burn. All GA aircraft regardless of make, model and condition burn and spit out engine oil. What differs is the quantity. Newer and better-maintained engines eject less, while older or less well-maintained engines spit out more. My experience with a couple of different M20Js is that they burn an average of a quart every 7 hours of flight time.

At an average of $10 per quart, you can easily crunch the number and it will tell you that you can average the hourly oil burn cost to $1.42 per hour.

One of the best ways you can keep your Mooney in good shape is to have an oil change every 25 hours. The M20J has an 8-quart sump. Mechanics typically charge 2 hours of labor for an oil change, and then there is $30 for the oil filter. In total that’s $230 for an oil change that should happen every 25 hours. Hourly, that works out to be $9.20.

Adding all these up gives you a total Direct Operating Cost of $87.62 per hour.

Fixed Cost

The Fixed Cost category captures all the costs of owning an airplane whether you fly it or not. There are three specific items that you will need to consider - maintenance, hangaring, and insurance.

For the Fixed cost category, the maintenance that is relevant is the Annual that needs to be done to keep the aircraft airworthy. Mooneys are not known to be inexpensive when it comes to annuals. Figure about $5,000 if you’ve been keeping your plane in good condition during the course of the year.

As far as hangaring, it fits nicely in a T-hangar. Try not to leave it outside in the element. What you save on hangaring you will end up paying for in dried-out seals, diminished paintwork, and quickly-eroding rubber shock disks. $7,200 a year for a T-hangar is worth the spend.

And finally, there is the premium for the insurance. 2.5% of the hull value for hull and liability is a good number to keep in mind. Now, this depends very much on your flight time. To drill down a little more, it would help a little if you had thousands of hours, but if you had no time in a Mooney, it won’t make much of a difference to the premium. $3,000 for a premium estimate is not a bad place to start.

In total, your Fixed Cost for the Mooney M20J will add up to $15,200 a year.

Long Term Costs

The third kind of cost is long-term costs. It doesn’t affect you in the present, but if you are not prepared for it, it will become significant when it comes due. Most aircraft owners set up a fund and put money in each time they fly so that when the time comes there is a kitty with the money to pay for it.

There are three primary costs that this fund will support, and since they are long-term issues, thus the name.

The first is the engine overhaul cost. To replace an IO-360 is an expensive affair. You should figure it to be about $50,000. But you don’t have to replace the engine at TBO. The overhaul could just end up having to get new cylinder heads and rework the pistons. In that scenario, if the case is still good, you don’t need to replace the whole engine. This will cost you about $20,000.

Lycoming recommends that overhauls be done at specific intervals. For this particular engine, it’s 1,800 hours. But to be really accurate and not get caught shortchanged, consider calculating the cause of an overhaul over 3 periods, or a total of 5,400 hours.

The reason is that the chances of needing a full engine replaced are accounted for when you do it this way. The case may be fine for the first 1800 hours, or the second, but the chances that you will need a new case at the end of the third 1800 is high. Adding up what it costs for a cylinders-only overhaul of $20,000 and a full engine change that costs $50,000, that works out to be $90,000 for 5,400 hours.

This means you should put aside $17 every hour you fly so that when the time comes, you will have enough set aside to get the engine overhauled.

Then there is the prop. The props need to be overhauled every twenty-four months or 2,000 hours whichever comes first. The prop overhaul will cost $1200.

Finally, you should set money aside for unintended upgrades, and maintenance. A good number is to pick $5,000. And you should put aside $15,000 for a new paint job every five years. Or, $3,000 per year.

All this adds up to two kinds of numbers that don’t add up. One is time-based, and the other is use-based, similar to the DOC and FC above.

To make sense of these numbers make an assumption of how many hours you will be flying your Mooney. If we assume that number to be 400 hours a year, then the money you set aside for paint, upgrades, and prop overhaul, which totals $8600 per year, or $21.50 per hour. Add this to the engine overhaul hourly allocation of $17 for a total of $38.50 per hour in Long Term Cost.

The Fixed Cost above, you will recall, is $15,200 a year. Divide that by 400 hours for an hourly cost of $38. And we already have DOC at $87.62. In total, it adds up to $164.12 per hour.

Speed

The Mooney M20J is a highly satisfying plane to be in command of. Just get used to it and you will start to feel like you would when behind the wheel of a precision sports car. It feels tight and sure. But all this is ruined by the fear from horror stories that come from the multiple accidents and incidents that haunt the M20 legacy.

The bottom line when it comes to managing the Mooney M20J is speed. While the speed for this little GA plane is off the charts for something comparable, it is that speed and the lack of the aircraft’s desire to slow down when you pull the throttle back that gets pilots in trouble.

Then there is the rumor that this plane has a habit of losing control and falling out of the sky when it gets too slow and you get pilots hesitant to throttle back early. The Mooney’s aerodynamics are so sound, that their wings stall progressively from the root to the tip in a predictable fashion. You won’t fall out of the sky unless you do not heed the multiple warnings of an impending stall.

To get a feel for this, take an instructor up with you, go up to 5,000 feet and set up the aircraft for minimum controllable airspeed. Set your speed to 10 knots above a stall and get used to the softer control surfaces and the attitude of the plane.

With the gear down and full flaps get used to how long it takes for the plane to bleed its airspeed down to 64 knots. When you fly it at this speed the stall horn should be audible. Because of this, you won’t have to use the speed brakes (in fact, I don’t know any pilot who uses them regularly, if ever).

After that, practice the stall and the recovery. Keep repeating this till you feel a visceral familiarity with how long it takes to get the Mooney to slow down and how easily it recovers from a stall.

About THE AUTHOR

Joe Haygood

Joe Haygood

After spending years watching every video I could find about flying, I finally scratched the itch and got my pilots license. Now I fly every chance I get, and share the information I learn, here.

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