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Home Uncategorized Mooney’s (Ac)claim

Mooney’s (Ac)claim

Published on November 21, 2008, in Uncategorized.

Fly faster. Fly farther.  That’s Mooney’s claim.

Since I just sold a new Cessna Turbo Stationair to a
2007 Mooney Acclaim owner, I have the rare opportunity to study Mooney’s top-end performer.  Here’s what I found.

Photos taken with Palm Treo phone.

Cruise Speed *
216 KTAS
Flight Conditions:  VMC, FL210, OAT -26°C, 3,310 lbs
Power Setting (Best Power):  32.1″Hg, 2,410 RPM, 21.8 GPH, 1,584°F TIT, 371°F CHT

See the
PFD and the MFD.

It’s NOT as fast as published in the POH.
   I used the “best power” cruise power settings from a chart in the aircraft, which turned out to
   be 1.5″HG higher power than called out in the POH.  This higher power setting, above, resulted
   in nice cool temps across the board.  The highest cruise power setting in the POH for 2,400 RPM
   is 30.5″HG, 19.9 GPH.  At this LOWER power setting, the POH reports 221 KTAS, 5 knots
   FASTER than what I obtained running 1.5″HG HIGHER power at the same weight.
And, this airplane is practically new – only 160 hours total time.

Fuel Consumtion

Operated by the POH, this Mooney Accaim must be operated full rich above 30.5″Hg – that’s 30 to 32 GPH.  Additionally the mixture must be operated on the RICH side of peak above 22,000 feet – so to attain any reasonable range for a flight at this altitude, limited max cruise power affords speed of 210 KTAS – nothing close to speeds as promoted.

About Speed
The discussion of speed uniformly ignores rate-of-climb, maneuvering, and approach speeds.  Unless the flight is long enough, it will take a fast-cruising Mooney over 100 miles to catch a faster climbing but slower cruising competitor like the high-wing Cessna.

Of what benefit is speed in turbulence when it’s necessary to slow to VNO (maximum structural cruising speed) or VA (manuerving speed)?  What good is speed on an ATC vector?  Low flap and landing gear extension speeds stymie the speed argument even more.

Compare the Acclaim and the Cessna 400
The speed figures and fuel flow figures are as tested by me.
Click here for my demonstration of the Cessna 400.

  Acclaim 400
Max Rate of Climb 1,240 fpm 1,400 fpm
Cruise Speed FL220 219 KTAS 220 KTAS
Cruise Fuel Flow 21.8 GPH 17.6 GPH
Maximum Structural Cruising Speed 173 KIAS 181 KIAS
Never Exceed Speed 194 KIAS 230 KIAS
Max Landing Gear Extention Speed 140 KIAS N/A
Useful load 897 lbs 1,041 lbs
Flight Total OMA to BWI 888 nm 93 gal, 4hr 14 min plus fuel stop 77 gal, 4hr 12min

The air conditioned option for the Acclaim further subtracts from the useful load listed above.  The Mooney cabin is cold at altitude.  The welded steel frame covered with a non-structural aluminum skin is not well-insulated.  The cabin heat is completely insufficient.  As far as I can tell, the cabin heat comes only from the defrost and this tiny port that resembles a 12-volt receptacle.

The Cessna 400 has an automatic climate control system with airconditioning as standard equipment.  The 400 automatically switches bewteen A/C and heat to maintain a cabin temperature selected electronically by the crew.  Composite fiberglass and honeycomb contruction of the fusage is likened to a giant thermos cooler, so it maintains a consistent cabin temperature very well.  On a recent wintertime flight, I delivered a Cessna 400 to its owner in Gillette, Wyoming.  The new owner flew me back to Sioux Falls, and not until cruise flight level at FL190 did it even occur to us to TURN ON the climate control.  The cabin maintained a comfortable temperature in sub-zero conditions for at least half an hour.

If you’re considering a new Mooney.  Call me.  888-310-8050.  I have a 2007 for sale.


9 Responses

  1. Joren

    My problem with your observations is that this aircraft is obviously equipped with the TKS icing package that reduces cruise speed by about four knots. In my experience the Acclaim and Acclaim Type S both run right about one knot under book for a standard aircraft. If you don’t believe me and my numbers, look at Flying and AOPA’s reviews. Flying got 239 knots from a book speed of 240 for the conditions and AOPA got 236 knots from a book of 237 on a near standard day with a non Type S. Also, in your comparison there you were running the 400 LOP and the Mooney ROP. I don’t care what Mooney says about LOP operation. In my experience you’re really going to screw your engine with high temperatures and screw you wallet with gas bills if you don’t go LOP. Just my two cents. I’d love to hear your comments. Please convince me that the 400 is a better aircraft than the Acclaim I fly so that I can get away from Mooney and there money problems without feeling like I’m giving up much performance. Feel free to Email me directly. Thanks, Joren.

  2. Dear Joren:

    I don’t know your source of information about speed loss with TKS, but indeed, this 2007 Mooney Acclaim (170 hours total time since new) is substantially slower than advertised, by 15 to 20 knots.

    Is there such thing as a “standard [Mooney] aircraft”? The Corvalis, with its superior useful load, includes air conditioning, oxygen, and Avidyne traffic, as standard.

    I subscribe to AOPA and Flying Magazines and find their aircraft reviews always flattering, never critical. My most recent flying experience was last week, delivering a Mooney Acclaim some 4,900 nautical miles to Germany. Here’s what I found:

    Max speed, claimed and bragged about by Mooney and magazines, can only if possible be attained at max power. Leaning is NOT authorized at max power neither by TCM nor Mooney. Full power results in fuel flow exceeding 33 gallons per hour that’s appropriate only for climb and initial level-off. Max continuous power is not recommended in the POH, or by any manufacturer that I know of.

    Mooney performance charts are calculated at reduced weight. You certainly know the Mooney useful load is not its selling feature. Airspeed on my transatlantic flight did not improve more than 5 knots while fuel (read weight) was consumed.

    Refer to these photos; this 2007 Acclaim is 15 to 20 knots slower than advertised:

    Lean of Peak Operations, FL230, 24” Hg, 2,400 RPM, 12.2 GPH
    Advertised: 205 KTAS, Actual: 184 KTAS

    Lean of Peak Operations (at lower weight), FL230, 24” Hg, 2,400 RPM, 13.0 GPH
    Advertised: 205 KTAS, Actual: 186 KTAS

    Best Power, Rich of Peak Operations, 30.5” Hg, 2,400 RPM, 18.8 GPH
    Advertised: 223 KTAS, Actual: 208

    A Cessna Corvalis TT is a better and more expensive aircraft. Its useful load, spaciousness, comfort, electrical system and standard equipment are all notable advantages over the Acclaim tp name a few. Please visit me for a demonstration. Then I would ask you to comment on this blog with your comparison.


  3. Joren

    I don’t know what you did to get the speed numbers you gave, but whatever it is the aircraft was seriously messed up. On regards to speed from the TKS, it is from a friend of mine who flew his 2008 Acclaim with TKS against a friend who had one without TKS and the difference was four knots according to the G1000 ground speeds for both aircraft.
    I’ve flown in a 400 back when it was a Columbia and was impressed by all the aircraft features except for a miserable failure to meet the book speed figures. The difference wasn’t like what you claim for the Mooney, but they failure was not inconsiderable. For example, what is the book speed at 3000 with the OAT 17 C? Me, I got 181 knots while right at gross weight, burning 25.1 gph. If we use the common 2 knots per thousand feet rule of thumb, which works well with Mooney’s, that would mean just 225 knots at 25000. A full 10 knots under the book speed. For comparison, I’ve flown a 2008 Acclaim Type S on lease from its owner since new, and I can assure you that the aircraft will make book speeds minus a knot or two. Also, about LOP operations, all I can say to Mooney is bullshit, I’m going to run the engine lean of peak wether they like it or not.
    I would come take a ride with you but as you seem to be more in the northern US, it would be somewhat inconvenient as I’m in Texas. Using the previously mentioned rule of thumb, I can tell you that the aicraft I fly will true right at 200 knots at FL 230 on 14 gph. These numbers conincide perfectly with book speeds, at least on the Type S. I also am qite unimpressed with Cessna sales people so far. Mr. __________ at _________ was most unhelpful when I asked him question and neglected to answer several Emails. By contrant, Mr. Kevin Bird and Cirrus promptly responded to my request for information and has been very helpful answering my questions. I thank you for your information but must inform you that when I buy a new aircraft, it will be a Cirrus. Regards, Joren.

  4. Dear Joren:

    N484DM, has a factory-installed TKS system. By all accounts of annual and rigorous pre-purchase inspection, it represented exactly a true and airworthy Acclaim. The photographs and data I present are affirmed by me, and N484DM’s new owner. Certainly, his bias is to read the gauges faster.

    Corvalis lean of peak actual flight performance is not “miserably” below book. As shown here on my demonstration, it was 220 KTAS, LOP at FL220:

    Run the Corvalis or a Mooney at best power, ROP, and add 10+ knots TAS.

    To emphasis to other readers, Joren extrapolated Corvalis speed from 3,000 feet using a “rule of thumb” method to arrive at what he figures the speed would be at FL 230.

    I demonstrate facts of the Corvalis to savvy buyers regularly, and I am happy to provide references from owners in the context of a purchase evaluation.

    If you decide to seriously evaluate a Cirrus in comparison to a Corvalis, and would be interested in my service, please contact me privately.


  5. Joren

    Mr. Wilson,
    My apologies if you thought I was saying that your numbers are not true. However, I have experience to the contrary and only have to wonder about the conditions during your test flights. Obviously,you have a bias towards Cessna aircraft and am sure, to use your words, “read the gauges faster”. I can’t help but notice that you didn’t give any temperature and/or weight information in your numbers. I would be quite interested if you could get me some real world numbers on a near standard day at gross weight for the 400. On the Mooney, I’m guessing that you were quite a bit over gross since you most likely had ferry tanks and survival gear if you were ferrying the aircraft to Germany. In my 1100 hours of flying (with about 800 in Mooney’s) I know that weight and temperature heavily affect cruise performance. It is not unusual to take off on a long flight at gross and see the cruise speed increase by five percent corrected for temperature and other factors by the time I’ve reached my destination. So please, if you really want me to seriously consider a 400, provide information to me that proves that the aircraft does not “miserably fail to meet book speeds”. It would be most helpful to have aircraft weight listed along with the speed. I’m currently not to the point of seriously comparing and test flying the aircraft as I’m waiting for to make sure I don’t have any finacial difficulties from the recession that would interfere with my ability to make payments on an expensive aicraft. If I do get to that point, I will be sure to contact you as you have been far more helpful than Mr —–.
    Sorry again if I offended you in any way (I do love Mooney’s so I’m obliged to defend them whenever I can)
    P.S. Please forgive my grammar. English was never my strong suit in school.

  6. No offense taken. I sincerely appreciate your commenting. Steve

  7. Joren

    Howdy Steve, you may remember the debate we had in your comments section about the Mooney Acclaims’ cruise speed. I’d like to inform you that I was part of a pilot in test this weekend using two identical Acclaims. Here’s how it went:

    We flew these to aircraft side by side about a month ago, and they had basically the same cruise speed when loaded the same (one aircraft was about 2 knots faster). Then one of the Acclaims was sent in for the TKS installation, and when it was returned to its owner, we performed the fly off again. Both aircraft loaded to gross, same power setting (confirmed with photographs, two of us who don’t have financial interest in the aircraft came along to make sure neither owner cheated in order to skew the results). Not surprisingly, the non-TKS equipped aircraft pulled away; by SEVEN WHOLE KNOTS. We flew the aircraft at FL250 to evaluate maximum cruise performance. non-TKS equipped Acclaim(both aircraft are 2007 non-S models): 232 knots (book speed 233), TKS equipped: 225 knots. Numbers taken at different altitudes indicate a strong trend towards one aircraft being seven knots slower. Interestingly, our real world cruise speeds (with the TKS equipped aircraft) were remarkably similar to your numbers, and slightly faster at lower power settings.

    By comparison FL250, 24″/2400RPM we got 203 knots and 196 knots for non-deiced and deiced respectively. That’s about 5 knots under book for the non-TKS equipped aircraft.


  8. I have to disagree with you. I’ve flown the Acclaim Type S (with TKS) and it performed very close to the POH, including on an Atlantic ferry flight to Poland.
    I don’t cruise at high power setting usually during those trips, typically around 65% power.

  9. Mark Finkelstein

    Hi Steve:

    I’m the owner of a Diamond DA-40 who recently moved to Texas from upstate NY. Because most of my family is in the Northeast, I’d like to get a faster plane with ice protections, and have been considering Columbia, Mooney and Cirrus. So naturally I was interested to get your take on those planes. Could you please provide an email address to continue the conversation?


    Pecan Plantation, TX

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