231 versus S35

[KLRDMD]

Today I had the opportunity to fly my previous Mooney 231 and my current S35 Bonanza back to back to back.

I flew the Bonanza 57AZ-KRYN.

Then I flew the Mooney 1:45 doing laps around KRYN at 7,500 ft to break-in two new cylinders that were just put on. Then I flew the Mooney to 57AZ.

My son drove me back to KRYN where I picked up my Bonanza and flew it back to 57AZ.

I'll deliver the Mooney to it's current owner on Monday.

I've been flying the Bonanza since January and hadn't flown the Mooney for about the same amount of time.

Thoughts/Comparisons:

I did a very thorough preflight since the Mooney just came out of a four month annual. Taxiing the Mooney out I thought one or more tires or wheels was out of round. It was so bumpy and almost jarring. Then I remembered the rubber discs on the Mooney. The Bonanza just glides down the taxi way.  Taxiing was a night and day difference.

I did the run-up and pre-takeoff check list and all was well. Taking the runway the acceleration was noticeably slower than I was used to. The extra 75 HP in the Bonanza makes a huge difference. This was at a density altitude of 5,000 ft on the runway. When it came time to pitch up, the airplane didn't want to do that. It felt like the control lock was still on. I was concerned for ½ a second until I specifically remembering checking "controls free and correct" during the run-up. It took a lot more back pressure than I remember.

Climbing out at 110 KIAS, just me and full fuel I was getting about 500 FPM climb. I did pull the power back to 35" at about 1,000 ft to slowly transition to 75% power as the IA wanted me to. Flying the Bonanza later I got 800 FPM at 110 KIAS and it was probably 5º warmer by then. Interestingly the fuel flow was identical. I knew this previously but the TSIO-360 at 210 HP in the Mooney and the IO-520 at 285 HP in the Bonanza, full rich each burn 25 GPH in climb. I climb both at 110 KIAS but get another 300 FPM in the Bonanza.

After about 1,000 ft AGL I put the airplane on autopilot so I could more closely watch the engine monitor and I flew a racetrack pattern for 1:45 before beginning my decent to land. When I took the airplane off of autopilot I again felt like the control lock was on. In all axes it was so heavy, much more than I remember but I'm sure it was normal. The landing was straightforward. The IA removed the cowl and did a thorough inspection and gave the airplane his blessing then I flew it back to 57AZ.

I used to love the feel of Mooneys, tight, precise and stable. But I've become spoiled by the amazing control response of the S35 Bonanza. There is simply nothing else out there like it. For many years I heard people saying that and didn't think much of it but once you've experienced it . . . I now know why people say the wonderful things they do about Bonanzas. 

The Bonanza also just feels so much better built. It is also a much larger airplane physically. There's only 350 lb difference in gross weight which is roughly 10%. When stepping onto the Mooney wing the step up wasn't that high; it is much higher in the Bonanza. Fueling the Mooney, the fuel nozzle on top of the wing was below my waist. Fueling the Bonanza a couple of hours later, it is well above my waist. While there is little practical difference in cabin width, the shape of the cabin and huge windows in the Bonanza make it feel so much larger inside. (The P210 I sometimes fly feels like I'm looking out the window of a tank, for comparison.)

The Mooney is more efficiency, no argument. I used to fly my 231 at 9.0 GPH for +/- 155 KTAS. I fly my Bonanza at 12.5 GPH for 170 KTAS. I would probably still have this Mooney if not for the 892 lb useful load. My Bonanza has 1,114 lb which is significant for me. I've owned 16 airplanes, four of which were Mooneys. Most of them I owned for a year or two. I may keep this airplane a long time.

Edited August 31, 2019 by KLRDMD

[SkyBound]

Thanks for sharing your insights.

What altitude/MP/RPM combination do you use to get 155 kts at 9.0 gph?

[KLRDMD]

Just now, SkyBound said:

What altitude/MP/RPM combination do you use to get 155 kts at 9.0 gph?

+/- 10,000 ft, 30"MP, 2500 RPM. That was 59% power LOP.

[Hank]

It's hard to compare 210 hp to 285 hp and expect similar cruise speeds and climb rates.

What is the Bo's cruise speed at 10,000, 2500 and 9 gph? What is its climb rate at 210 hp?

[jetdriven]

Bonanza is a bigger, more powerful, and more useful load airplane than a Mooney and it takes a third more fuel do to it. If you need that, buy one. 
In IMC, a Bonanza is a lot easier to lose control and either break it up or crash. That heavier control response is called stability and makes for a safer airplane in the soup. 

[gsxrpilot]

I actually think it’s a good comparison. The Bo will carry more weight for a slight penalty in fuel economy or range. But if you don’t need the UL, the Mooney is slightly more efficient.

[KLRDMD]

2 minutes ago, bluehighwayflyer said:

All of you are absolutely correct.  Too bad you never owned an Ovation before meeting your one true aeronautical love, Ken.  I would have enjoyed that comparison even more.  Still the pros and cons would be there, but the comparison would be more apt.

I owned a Bravo and have recent Ovation time. The Ovation would cost at least twice and probably three times what I have in the Bonanza. It would be both more efficient and faster than the Bonanza (assuming a 310 HP version) but wouldn't give me the useful load I need. How's that for a quick and dirty comparison? 

[M016576]

55 minutes ago, KLRDMD said:

I owned a Bravo and have recent Ovation time. The Ovation would cost at least twice and probably three times what I have in the Bonanza. It would be both more efficient and faster than the Bonanza (assuming a 310 HP version) but wouldn't give me the useful load I need. How's that for a quick and dirty comparison? 

Unless it’s a Missile or a screaming eagle.... all the speed/efficiency, and the useful load to go along with it (~1150 lbs).

Ovations are beautiful... but wouldn’t they be better with a 1150-1200lb useful?  It’s too bad that hasn’t happened for mooney.

excellent write up though- quite objective,  I feel the same way about the Bonanza.  Light on the controls, fast, nimble.  The Mooney could be lighter on the controls but it wasn’t designed that way, in part due to using rods and turnbuckles instead of pulley’s and cables.  Those same rods also add weight that could have been reduced (significantly) by using cable.  But one of Mooney’s selling points has always been the control rods.. much like the “roll cage.”  It leads to a heavier feel on the controls and a lower useful load in exchange for possibly a bit more safety (assuming the rods are more robust than cable).

Edited September 1, 2019 by M016576

[kmyfm20s]

I’m not familiar with all the systems the S35 has in it. I am jealous of the S35 landing gear. I think comparing a vintage plane vs modern in regards to useful load is hard. Does the S35 have the redundancy (batteries, busses, alternators) and built in O2 like an Ovation? I recall many early ovations having 1100 Lb UL and don’t have the CG issues. All brands get fat with age:) As far as horsepower and climb goes. The Eagle will be faster, most efficient and have less climb with only 240 hp. The Ovation will be faster, more efficient and climb as well with 280 hp. The O3 will be faster, more efficient and climb better than all of them with 310 hp. Handling is always a personal preference for your type of flying. I tend to fly straight and level a lot for traveling. I’m not out dog fighting so I have appreciated the stable controls especially in IMC of the Mooney. Now if I was racing pylons or flying bush planes then I would get more excited about handling. My biggest complaint with Mooney’s for my personal use are the small cargo door. I wish I could load bikes, cooler and saddles easier and it not be such a process. My plane has 1057 Lbs UL and I have air conditioning. 

[M016576]

33 minutes ago, kmyfm20s said:

Handling is always a personal preference for your type of flying. I tend to fly straight and level a lot for traveling. I’m not out dog fighting so I have appreciated the stable controls especially in IMC of the Mooney. Now if I was racing pylons or flying bush planes then I would get more excited about handling.

Have you flown a Bonanza?  

I love my mooney.... but it’s not “stability” that the Bonanza lacks (it’s exceptionally stable).  It’s just that it’s noticeably lighter on the controls.

a Bonanza is Positive-> neutral in static stability (much like a mooney), and dynamically positively stable.  And it has a very light control feel (it doesn’t take much force to deflect the flight controls).  The mooney is also positive to neutral in static stability and dynamically positively stable, but it requires more force to deflect the flight controls... hence the “heavier feel.”

I’ve heard a lot of pilots say that the mooney is more “stable” due to its heavier flight controls... but that’s not necessarily aerodynamically accurate- stability, as defined in aerodynamics, has to do with an aircrafts resistance to change of state, not how much force it takes to change the state itself.  It’s more about what happens when you let go of the yoke, rather than how much force is required to turn the yoke.

[aviatoreb]

4 hours ago, M016576 said:

Have you flown a Bonanza?  

I love my mooney.... but it’s not “stability” that the Bonanza lacks (it’s exceptionally stable).  It’s just that it’s noticeably lighter on the controls.

a Bonanza is Positive-> neutral in static stability (much like a mooney), and dynamically positively stable.  And it has a very light control feel (it doesn’t take much force to deflect the flight controls).  The mooney is also positive to neutral in static stability and dynamically positively stable, but it requires more force to deflect the flight controls... hence the “heavier feel.”

I’ve heard a lot of pilots say that the mooney is more “stable” due to its heavier flight controls... but that’s not necessarily aerodynamically accurate- stability, as defined in aerodynamics, has to do with an aircrafts resistance to change of state, not how much force it takes to change the state itself.  It’s more about what happens when you let go of the yoke, rather than how much force is required to turn the yoke.

Leave it to the professional dog fighter to use the correct phrasing regarding aeronautical stability terms.

Earlier you said that it was rods that creates a slower feel on the controls for mooney.  I always assumed there is a cam somewhere in there in the mechanisms, which is essentially like a gearing, that slows down how much push creates how much flight control deflection. If Al had wanted a lighter feel he could have simply chosen a smaller cam but he designed for a more "steady" feel as per his tastes.  Esp in roll.

Separate, for those with big engines on the nose - talking to you Job - these Mooney's are a bit heavy in pitch compared to the smaller Mooneys since they have relatively forward CG, but I found for mine when I took 35lb off the nose, it became much lighter in pitch and the balance feels much more harmonized in pitch.

I remember my old DA40 was MUCH quicker on the controls but I have always felt the Mooney's stead control feel is a lot like an autobahn read road car like a BMW.  I like it.  It is a design choice.  My Da40 was VERY hard to hand fly through instrument maneuvers - I know because I did my IFR ticket in it - and it had no autopilot.  Which is what started me down the road of selling it.  Bonanza was my head-head finalist vs Mooney but something you (KLRDMD) didn't mention - there's isn't much leg room for tall pilots in the front of a Bonanza.  Great planes though....if you don't mind slow planes.  Hahha....  seriously though you did say, but still it seems as much a comparison between a TSIO360 vs a IO520 when discussing speed and climb rate.  As Job said, think also missile if you want a normally aspirated big bore and climb at 1500fpm, cruise at 190, and carry the same useful load (rough from my head - I don't own a missile but I have been with Seth in his..).  Still great review.  I have been with Alan in his Bonanza and I was very impressed....despite the leg room.

[jetdriven]

6 hours ago, M016576 said:

Have you flown a Bonanza?  

I love my mooney.... but it’s not “stability” that the Bonanza lacks (it’s exceptionally stable).  It’s just that it’s noticeably lighter on the controls.

a Bonanza is Positive-> neutral in static stability (much like a mooney), and dynamically positively stable.  And it has a very light control feel (it doesn’t take much force to deflect the flight controls).  The mooney is also positive to neutral in static stability and dynamically positively stable, but it requires more force to deflect the flight controls... hence the “heavier feel.”

I’ve heard a lot of pilots say that the mooney is more “stable” due to its heavier flight controls... but that’s not necessarily aerodynamically accurate- stability, as defined in aerodynamics, has to do with an aircrafts resistance to change of state, not how much force it takes to change the state itself.  It’s more about what happens when you let go of the yoke, rather than how much force is required to turn the yoke.

Let go of a trimmed Mooney for a minute or two.  It flies on and on. The dihedral keeps it flying straight.  Now do the same in a Bonanza. After 20-30 seconds it rolls off into a spiral dive.  

[M016576]

1 hour ago, aviatoreb said:

Earlier you said that it was rods that creates a slower feel on the controls for mooney.  I always assumed there is a cam somewhere in there in the mechanisms, which is essentially like a gearing, that slows down how much push creates how much flight control deflection. If Al had wanted a lighter feel he could have simply chosen a smaller cam but he designed for a more "steady" feel as per his tastes.  Esp in roll.

Separate, for those with big engines on the nose - talking to you Job - these Mooney's are a bit heavy in pitch compared to the smaller Mooneys since they have relatively forward CG, but I found for mine when I took 35lb off the nose, it became much lighter in pitch and the balance feels much more harmonized in pitch.

Yes- exactly.  It’s “geared” for that feel- and in pitch (with the Missile and Rocket, anyway) for a lighter engine.

i haven’t flown a long body- so I can’t speak to how the pitch feel compares to a rocket/missile or regular J/K (or short body)

[M016576]

56 minutes ago, jetdriven said:

Let go of a trimmed Mooney for a minute or two.  It flies on and on. The dihedral keeps it flying straight.  Now do the same in a Bonanza. After 20-30 seconds it rolls off into a spiral dive.  

I’ve flown 2 bonanzas- a V35B and a S35, and 2 other aircraft that use the same wing (T-34B and T-34C but both these had aileron and rudder trim, too).  So my sample size is somewhat limited and subjective, and I also wasn’t “grading the aircraft” on this point- so actively looking for it.  To me, though- they seem to fly similarly from a stability standpoint to the mooney’s I’ve flown, with the exception of a far lighter control force required in the Bonanza and T-34.

bonanza’s do have dihedral in the wing, which does as you say (helps with static stability).  I wonder if it’s easier for a Bonanza to fall out of rig? Upon research, I found this scholarly article which is very interesting (from a aero-nerd perspective) on how lateral stability in aircraft, which discusses FAA certification standards and how they have evolved.

https://pdfs.semanticscholar.org/b312/58da0a72490bb62cc7b3bd1de1faaa4749ad.pdf

 

Just as a side note- with my first J, the aircraft would bank right and the nose would drop after about 15 seconds if I let go of the controls... at least until I had the controls re-rigged, at which point it flew much “truer.”  I don’t think I could get a minute of hands off time though (on either of the mooney’s I’ve owned... but that’s something for me to try!).

Chapter 2 here discusses static vs dynamic stability in better detail than I do.

https://www.cnatra.navy.mil/pubs/folder5/t34c/p-330_ch9.pdf

Edited September 1, 2019 by M016576

[kmyfm20s]

7 hours ago, M016576 said:

Have you flown a Bonanza?  

I love my mooney.... but it’s not “stability” that the Bonanza lacks (it’s exceptionally stable).  It’s just that it’s noticeably lighter on the controls.

a Bonanza is Positive-> neutral in static stability (much like a mooney), and dynamically positively stable.  And it has a very light control feel (it doesn’t take much force to deflect the flight controls).  The mooney is also positive to neutral in static stability and dynamically positively stable, but it requires more force to deflect the flight controls... hence the “heavier feel.”

I’ve heard a lot of pilots say that the mooney is more “stable” due to its heavier flight controls... but that’s not necessarily aerodynamically accurate- stability, as defined in aerodynamics, has to do with an aircrafts resistance to change of state, not how much force it takes to change the state itself.  It’s more about what happens when you let go of the yoke, rather than how much force is required to turn the yoke.

Yes, I have flown a Bonanza and honestly enjoyed almost every plane I have flown. If I was constantly hand flying either plane for long cross country or IMC flights I still prefer the feel of the Mooney. Let’s face it autopilot does most of this work. I also didn’t like how the V tails like to wag their tails in anything but perfect air. I felt like the mid body and especially the long bodies didn’t do this as much and wouldn’t get the passengers sick.  I personally don’t fit very well in the Bonanza my head get cramped into the ceiling.  I will eventually probably buy a turbo normalized A36 and have the cushions modified so I fit. I now have a family of 5 but rarely do we fly together. I would be more interested in those barn doors for loading everything and the A36 doesn’t yaw and wag it’s tail like the V tails.

[M016576]

12 minutes ago, kmyfm20s said:

didn’t like how the V tails like to wag their tails in anything but perfect air.

That “Dutch Roll” is an effect of the high positive dihedral in the tail plane.  I don’t like it either- it feels weird... but it’s a side effect of the tail plane being so dynamically stable (that it over corrects).

Edited September 1, 2019 by M016576

[jetdriven]

19 minutes ago, M016576 said:

I’ve flown 2 bonanzas- a V35B and a S35, and 2 other aircraft that use the same wing (T-34B and T-34C but both these had aileron and rudder trim, too).  So my sample size is somewhat limited and subjective, and I also wasn’t “grading the aircraft” on this point- so actively looking for it.  To me, though- they seem to fly similarly from a stability standpoint to the mooney’s I’ve flown, with the exception of a far lighter control force required in the Bonanza and T-34.

bonanza’s do have dihedral in the wing, which does as you say (helps with static stability).  I wonder if it’s easier for a Bonanza to fall out of rig? Upon research, I found this scholarly article which is very interesting (from a aero-nerd perspective) on how lateral stability in aircraft, which discusses FAA certification standards and how they have evolved.

https://pdfs.semanticscholar.org/b312/58da0a72490bb62cc7b3bd1de1faaa4749ad.pdf

 

Just as a side note- with my first J, the aircraft would bank right and the nose would drop after about 15 seconds if I let go of the controls... at least until I had the controls re-rigged, at which point it flew much “truer.”  I don’t think I could get a minute of hands off time though (on either of the mooney’s I’ve owned... but that’s something for me to try!).

Chapter 2 here discusses static vs dynamic stability in better detail than I do.

https://www.cnatra.navy.mil/pubs/folder5/t34c/p-330_ch9.pdf

The lateral stability is almost neutral on a Bonanza.  A Mooney is slightly positive. I like to fly both, the Beech is fantastic in VFR, and the Mooney is easier IFR. 

[KLRDMD]

3 hours ago, aviatoreb said:

Bonanza was my head-head finalist vs Mooney but something you (KLRDMD) didn't mention - there's isn't much leg room for tall pilots in the front of a Bonanza.  

. . .  but still it seems as much a comparison between a TSIO360 vs a IO520 when discussing speed and climb rate.  

Grated there is more leg room in the long axis in a Mooney but this is the first I've ever heard of a lack of legroom in a Bonanza. Certainly there is tremendously more lateral legroom in the Bonanza which to me makes it a lot more comfortable. I'm stuck with my legs in a tube in a Mooney. I've had a number of tall people in the Bonanza but one has even mentioned a lack of legroom. Interesting. I'll have to start asking people about that.

I compared the Mooney I used to own to the Bonanza I currently own as I just happened to fly them back to back to back yesterday. Nothing more than generalities about my thoughts from that day of flying where meant. It was interesting when I again realized the the fuel flow on takeoff was identical between airplanes. Other than that, they are two different airplanes for somewhat different missions.

[Hank]

The turbonormalized A36 that I have several hours in, along with a gusty crosswind landing before I hit 200 hours, flew well. The autolean feature was nice, the climb was great, but the fuel flow was significantly higher than my C, enough so that it would have been difficult for me to maintain proficiency much less train intensively for IFR. Kind of like when I drove a friend's new Mercedes V12 coupe ~2012; it was much nicer than my XJS V12 convertible, but not something I could realisticly expect to own & operate.

My friends load a lot of stuff through their big barn doors, but I'm pretty good at packing my short body, too. Need to find pictures. When I flew relief after Hurricane Florence, I arrived at RDU in just over 2 hours plus about 20 minutes vectoring for spacing to land. Planning my first trip without refueling, I was the only single I saw on the page-and-a-half list with more than 350 lbs available (with half tanks and just me, I had > 600 lb useful load). Being a short body, I ran out of cubic feet well before useful load, but I took everytbing that I could fit, including unpacking boxes and putting things in gaps.

It's all about what plane fits your pocketbook and your needs.

Edited September 1, 2019 by Hank

[KLRDMD]

9 hours ago, kmyfm20s said:

Handling is always a personal preference for your type of flying. I tend to fly straight and level a lot for traveling. I’m not out dog fighting so I have appreciated the stable controls especially in IMC of the Mooney. Now if I was racing pylons or flying bush planes then I would get more excited about handling.

My biggest complaint with Mooney’s for my personal use are the small cargo door. I wish I could load bikes, cooler and saddles easier and it not be such a process. 

I used to say the same thing about handling. I justified the handling on my Seneca the same way. It is on autopilot 90% of the time so what does it matter. But once you regularly fly an airplane with controls as perfectly harmonized as the Bonanza is, maybe you would see things differently.

The baggage area is one major difference between Bonanzas and Mooneys. All Mooneys have the same dimension door, and the lift up and over requirement and I believe all have the same maximum weight (120 lb?). I have the large baggage door in my Bonanza which is much lower than a Mooney and the volume is about three times that of the Mooney. The maximum weight of 270lb is a bit higher than the Mooney too.

[amillet]

I flew with a friend to drop his Mooney off at a broker to be sold. The broker flew us to a nearby commercial airport in his V-tail. I climbed aboard first to sit in the back seat (225 lbs.). The nose wheel lifted off the ground and the tail dropped to the ground. Very delicate balance point.

[KLRDMD]

1 minute ago, amillet said:

I flew with a friend to drop his Mooney off at a broker to be sold. The broker flew us to a nearby commercial airport in his V-tail. I climbed aboard first to sit in the back seat (225 lbs.). The nose wheel lifted off the ground and the tail dropped to the ground. Very delicate balance point.

I have crawled into the baggage area to put my new registration in the holder on the very back of the baggage area and that didn't happen. And that is with the 42 lb air conditioning unit there. The arm of the baggage area is much further aft than the second row of seats. Sorry but something's fishy with that story.

[amillet]

3 minutes ago, KLRDMD said:

I have crawled into the baggage area to put my new registration in the holder on the very back of the baggage area and that didn't happen. And that is with the 42 lb air conditioning unit there. The arm of the baggage area is much further aft than the second row of seats. Sorry but something's fishy with that story.

I won’t take offense that you imply that I am a liar

[KLRDMD]

Just now, amillet said:

I won’t take offense that you imply that I am a liar

Not saying you're a liar. Saying something not right. 

[donkaye]

When I am flying with someone, I judge their airmanship by how smoothly they fly the plane.  If you're flying aerobatics alone, jerk the plane around as much as you want.  If you're flying privately or commercially, fly for the passenger, even if it is just you.  That means maneuvering the plane so a passenger doesn't know your doing it.  That  involves control pressures, not control movement.  With control pressures I don't think it makes much difference whether its a Mooney or some other type airplane, the piloting is the same, the control pressures might be a little different..