Turbo Vs. Normally Aspirated

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Looking for thoughts regarding a purchase of a T182T or 182T. My
mission is for a family of four (500 lbs total), plus 100 lbs luggage
to fly 500 miles east of the Rockies. If I were to buy a turbo 182,
I could afford a 2004 - 2006 model (g1000, no WAAS, KAP 140), or a
2007 182T (g1000, WAAS, GFC 700, A/C, Synthetic Vision). Is the
turbo worth it? Do I really need the bells and whistles (i.e.
synthetic vision, WAAS)? We sold our 2006 DA40, and I have recently
received the IFR designation. The A/C would be nice in Texas where we

-- Scott Zodin, November 26, 2008


As Steve, below, notes, the KAP 140 is a fairly crummy and maintenance-prone autopilot. The Garmin autopilot would be worth a lot more. If you don't intend to fly high and breathe oxygen, the turbo is probably a negative due to increased maintenance costs/complexity. The turbo will inevitably fail and take part or all of the rest of the engine with it.

-- Philip Greenspun, December 30, 2008


Congratulations on earning your instrument rating.

Synthetic Vision and WAAS are not necessary by any stretch of the imagination. Recall, not too long ago Cessna 182's were flying around just fine with only 2 NAV radios and 2 OBS heads. GPS and moving maps are a massive help for situational awareness not to be eschewed.

500 mile trips means about 3 hours in the airplane and if you are doing single-pilot IFR the autopilot will be a massive increase in safety. Commercial operators are not allowed to operate single-pilot IFR without an autopilot. They are probably more proficient and experienced and yet the FAA realizes the workload IFR entails.

The air conditioning systems are notoriously weak and heavy. Consider its affects on your useful load. Its one more thing to maintain. You will only use it on the ground. Its use is most likely not permitted for takeoff or landing (go-around considerations).

The turbo is great if you are flying at the higher altitudes. If you are crossing the Rockies then it might be a good idea. Look at the MEA's for the trips you do often and if they are above 10,000' then it would be great. Also consider if you are going to go higher what you are going to do to meet the oxygen requirements. Nasal cannulas are terribly uncomfortable.

Air conditioning and turbo are usually coupled with a pressurized cabin. Have you considered a P210? Maybe your trips don't really need a turbo.

-- Bradrick Pretzer, November 27, 2008

Thanks Brad, I still hope we can do some flying together. The other option is a 2004-2006 SR-22. I still view myself as a "student" pilot. The reputation of the Cirrus has me a bit worried. I know it has bit more than one low time pilot. On the other hand, on paper at least, it is nearly perfect for us. Given that Cirrus between 2004-2006 cranked out as many planes as possible, there is now an ample supply to choose from. WAAS is still a rare commodity on the older birds, but they still offer glass, a/c, inadvertent icing, good speed and comfortable cabin. Resale also worries me. However, with this much plane, we would likely hold it longer than the Cessna.

-- Scott Zodin, November 27, 2008

I might add that some ice protection may be worth considering for the wish list. East of the Rockies and high, in IFR, it may be more of an issue then you would want. You may find SR22 with TKS. Just a thought. Fabio

-- fabio savoldelli, December 1, 2008

hey scott- last year i bought a new 2007 T182T (w/out a/c) and went through the same exercise. i live in southern california so the a/c is a little less of an issue, but the turbo is really a necessity as virtually all of my flights involve climbing over mountains to get in/out of the southern california basin. synthetic vision and waas are available on all g1000 (+/- 8K to upgrade to synthetic vision and not sure about waas), so, aside from the turbo, the real issue that you should consider is the gfc 700 versus the kap 140. i wanted to save a few bucks and considered buying an 06 (or earlier) model (with the kap 140) but ultimately concluded that the gfc 700 equipped plane would ultimately hold its value better, and be safer and more fun to fly. there really is no comparison between the fully integrated gfc 700 and the not-so-impressive kap 140. the garmin autopilot is fully integrated, has vnav, and holds altitude, heading and vertical track extremely well. it is incredibly easy to fly. the kap 140 is much less reliable, porpoises, has problems w/the servos which require expensive maintenance/replacement, and generally does not perform nearly as well as the garmin. bottom line here is that i sure am glad that i spent a few extra $$ to get what i wanted and believe that i will have something that will be much easier to sell when i'm ready to upgrade. good luck to you. hey, by the way, did you go to UT in the late 80's? i graduated from there in 87. take care. -steve

a few thoughts on the a/c: for 20K and the significant weight penalty, i think its a terrible investment (even in texas). you are used to the da40 (low wing) with the giant glass bubble that coverts your cockpit into a microwave owen. the high wing is entirely different and acts as a sunshade. i have taken my plane (in the summer months) into austin, dallas, las vegas, palm springs and other terribly hot places (blythe, ca at 117 degrees!!). just open the side windows on the ground and use the vents once airborne and you should be fine. look on aso and controller and you'll notice that there are very few a/c equipped 182's......

-- Steve Horowitz, December 17, 2008

UT, ZBT Class of '85. Your name is familiar, had far fewer brain cells back in the day. Still torn on what to buy. We are looking at the T182 and a 2006 SR-22. The 22 is a big bang for the buck because there is a gazillion on the market. I am leaning T182 because of g1000 and gfc-700.

-- Scott Zodin, January 6, 2009

Hi Scott, I purchased a new 2007 T182T last year. Great airplane and I am very happy. I would only get a turbo. When you are spending this much money anyway you might as well hve the extra performance. I added a Bendix KTA 870 and Terrain too. I would pass on the A/C. Regarding your 500 lbs of passengers plus 100 baggage, I ran the weigh and balance and if you and your front seat passenger weigh 150lbs each and the rear seat passengers weigh 100 lbs each and you put 50lbs each of baggage in baggage areas A and B for a totalof 100 lbs you will only be able to cary 60 gallons of usable fuel when you take off. I figured 50 gallons used during the flight of 500 miles etc. Doesn't leave you much reserve. Good luck. Write if you have any questions. Jim Griset

-- Jim Griset, January 12, 2009

Although an older thread, interesting. 2012 and I'm in a similiar predicament, but really can't afford the G700. Looking at the 2004 turbo. Is the KAP-140 really that poor or maintenance prone? Newer pilot with low hours so my experience is limited.........

-- andy nahas, March 11, 2012

The Garmin autopilot is vastly superior to the KAP 140 autopilot. As you noted, my experience (I have my aircraft on leaseback at an FBO) has also been that the Garmin autopilot is more reliable and less maintenance-prone than the KAP 140, but that is not the real reason why the Garmin GFC700 autopilot is so great.

I can list these reasons:

1) The GFC700 autopilot controls the airplane precisely and promptly. The GFC700 is AHRS-based (the AHRS is the equivalent of the attitude and directional gyros). The KAP 140 is based on roll information from the turn coordinator.

2) The servos in the GFC700 system, which manipulate the flight controls, are far better, both in strength and quality.

3) The GFC700 is tightly integrated with the Garmin G1000 flight deck. One obvious advantage, for example, is that you don't need to enter your baro setting twice as you do with the KAP 140. Also, you have a clear indication of the autopilot's operation on the G1000 PFD/MFD. For the KAP140, you have to look at the KAP 140's small display.

4) The addition of FLC (flight-level change) for climbs is a great feature of the GFC700. It allows you to specify to climb at a given airspeed rather than fpm, because you really want the aircraft to maintain Vy or Vx or whatever, and you accept the fpm that you get, not vice versa.

The G1000 with the GFC700 is used all the way on the Cessna line from the Cessna 172 (2008 and after) through the Mustang twin-engine jet. It is truly a world-class autopilot and not that far removed from the autopilots, like the Rockwell Collins Pro Line, that you will find on large aircraft.

Finally, the autopilot is far more important for IFR flying than VFR flying. If you are flying IFR or plan to learn, the GFC700 is worth a great deal. If you look at used single-engine, piston aircraft, you will see a clear price break at the year when Cessna changed the aircraft from KAP 140 to GFC700. My rough estimate is that the market values the GFC700 at about $50,000 to $70,000 over an equivalent aircraft with the KAP 140.

The autopilot is kind of like the location in real estate. It is something, at least for smaller aircraft, that is impractical and usually impossible to change. And, it greatly effects your use and enjoyment of the aircraft for anything other than short, training flights. In short, in 2008, I switched from flying the KAP 140 to the GFC700 and can't say enough about how great the GFC700 has proven to be.


-- Todd Ramming, March 11, 2012

I know this is originally an old post but I thought I had some good input to put in here. a little background on me I am a proud owner of a 2012 Cessna 182T Skylane, so I went through the same turbo vs. non-turbo question. I currentl hold commercial multi-engine, commercial single engine, instrument airplane, CFI checkride next week.

1. GFC700 does still have the turn coordinator located behind the firewall for the autopilot, however it is more proactive of a system than reactive since it can integrate with the G1000 and trends.

2. I have a lot of experience with both systems as my 182 has the GFC700 and I have flown a lot with the KAP140 in older 172S, 182T, DA42s etc. Go fly a simple full approach to an ILS with both systems and you will quickly see how the KAP140 is far behind from the GFC700. The FLC is my favorite feature, as stated in the post above its great. also the GFC700 is beautifully integreted with the SVT.

3. The turbo vs. non-turbo is a very specialized debate that only you can answer. Its not like a car where having the turbo in the name is where its at. I could have easily gotten a turbo one instead, however I thought of my mission. I am in Florida, and will 99% of the time be flying east of the rockys. The turbo is about 100lbs heavier, therefore equating into 100lbs less useful load. To me that extra 100lbs was more worth it than the turbo. Becuase i am in florida hot and high performance is not an issue, and for the once or twice i may ever traverse the rockys there are plenty Vairways with MEA's between 9-11000 feet. And in the end of the day at cruise, if you were doing 500 mile legs in each, assuming you are at cruise the entire time (which you never are so the time to climb would further reduce the time difference of my next figure) would only equate to a total time difference of 34 minutes faster in the turbo, again not much of a difference espicially when you figure that increased climb time to FL180-FL200. I always cruise at 140ktas or higher depending on my weight (extra 1ktas per 125lbs below max weight)in my NA between 9,000-11000ft msl at 69%-74% power. In the turbo you would need FL180-FL200 to achieve 165ktas, in the lower altitudes the turbo has the same speeds with increase GPH. To me the fuel was no consideration but to some it may, the turbo will burn more fuel and will also be a little more costly, but again you need to look at your mission to see what fits. If your mission does not require a turbo dont buy it, youll find that 100lbs more useful. buy what fits your mission 80%-90% of the time. So far I have never found a need for the turbo and infact have found a need for that 100lbs many times. I often fly for dinner or lunch or whatever with several friends to nearby airports. Something to keep in mind is the 182T and T182T need to land 150lbs less than you can takeoff. my friends and family who I often fly with and myself weight 170, 165, 160, and 150 equating to 645Lbs. now the useful load in my specific aircraft is 1077.7lbs. I often fly to many airports between 25-30nm with 4 people aboard. Now say you will burn 6.5 gallons each way since the flight time will be about 20-25-30 minutes when alls said and done. (not including taxi) you could only depart 39Lbs heavier than 950lbs useful load becuase of the max landing weight becuase 39LBS is all youll burn in fuel getting there. meaning my useful load now really went down from 1077.7lbs to 989lbs. In my aircraft thats fine take 989-645 and you are left with 344lbs of fuel you could take and be able to make that flight and not land overweight. that is 57 gallons of fuel. at 13gph thats 4.4 hours. meaning if you were going further you could take even more gas. now lets say you were completing that same mission in the turbo version, this time you would have to take 100lbs less gas (becuase of the weight of the added turbo since your usefull load is now 977.7, and your max landing useful load is only 872.7Lbs (977.7-150 for max landing limitation + 45Lbs for the fuel youd burn off) for the same trip mentioned above, meaning your total onboard gas would need to weigh 244lbs or 40.6 gallons, in the turbo at 15gph thats only 2.7 hours of fuel, right there because of that 100lbs of turbo. keep in mind that 100lbs is 16.6lbs of gas, equating to 1.1 hour in a turbo or 1.3 hours in an NA no matter which way you look at it at the end of the day in the turbo you will always carry 1.1 hours less gas if you must take everything on the plane.

what I just stated above is a common lack of research that many pilots do not make. At first I as well was thinking great the turbo has 986lbs useful sounds great, until i realized i would need to land 150lbs lighter which when flying shorter legs that dont burn as much fuel really makes a big difference. So for to go with the NA after finding this out was a no brainer. So far it could not be better, I fly regularly on shorter legs with 4 people so I dont need to fly high, and i dont need that hot and high takeoff performance, but I do need that extra weight ability. even if you take less gas, thats still 100lbs of something you can take becuase of that 100lbs more of plane.

and lastly as far as the AC goes again save yourself the weight, I have the arctic air system which is great, the model I have weighs 49lbs fully loaded and can cool the cabin by 30 degrees F on high (which i only need on the ground and often use it for prefligth cooling) it is great becuase it does not require the engine to be running or the battery on for it to run, and if I need that extra 49lbs i simply just dont take it along with me. and it also costs all less than 1k, beats 20k for A/C.

I know what I said was extremely detailed, however when you really look into there is a lot more research that needs to be done when looking at a plane. if you did not research what I said above you could suddenly find yourself in a pickle if you bought the plane without knowing. Again it depens on your mission if i was in hot and high in the mountains or crossing the rockys every week id buy the turbo and sacrafice the useful load, but since im not i sacraficed the turbo and went for the extra useful load.

-- Justin Dahan, June 7, 2012

For what it is worth I have owned a 2004 T182T for 5 years. I have had no problems or maintenance relating to the auto pilot and find it works very well. Perhaps if I tried the 700 I would get spoiled but not knowing any better the KAP 140 has done a great job for me and I fly IFR regularly. As for the turbo, my insurer actually offered me a lower rate if I went with the turbo. Since I live in the Rockies he told me it would be safer to fly a turbo aircraft.

-- Dan Wyson, August 24, 2012