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Posted

Well, I can tell you that my 220 horsepower M20K is running an average Hobbs fuel flow of 10.05 gallons per hobbs hour.  From purchase to date (June 2011 to March 17, 2012) I have done one annual inspection and flown a total of 59.6 hobbs hours.


My 200 hp M20J would run about 8.0-8.5 gallons/hobbs hour, IIRC.


It isn't necessarily the turbo that will eat you.  So far, for me, it's been in the more complicated systems, like my dual alternator setup.  An overhauled coupler for the alternator behind the engine (geared to the camshaft) accounted for about $1600-1700 in troubleshooting, parts, and labor out of my $2100+ in squawks at this annual.


Other than that, it was a pretty painless annual.  But my preferred MSC did a good prebuy and fixed a lot of squawks at the time of purchase.

Posted

Quote: Parker_Woodruff

Well, I can tell you that my 220 horsepower M20K is running an average Hobbs fuel flow of 10.05 gallons per hobbs hour.  From purchase to date (June 2011 to March 17, 2012) I have done one annual inspection and flown a total of 59.6 hobbs hours.

My 200 hp M20J would run about 8.0-8.5 gallons/hobbs hour, IIRC.

It isn't necessarily the turbo that will eat you.  So far, for me, it's been in the more complicated systems, like my dual alternator setup.  An overhauled coupler for the alternator behind the engine (geared to the camshaft) accounted for about $1600-1700 in troubleshooting, parts, and labor out of my $2100+ in squawks at this annual.

Other than that, it was a pretty painless annual.  But my preferred MSC did a good prebuy and fixed a lot of squawks at the time of purchase.

Posted



Ward,


Unfortunately I didn't keep down-to-the-penny costs for my M20J. 


 


Also, cost per mile on the M20K is totally dependent on altitude, so an hourly figure is the best way to convert that to $/mi.


 


I think my costs in 2012 dollars will stabilize at about $140-150/hour, as best I can tell. That includes everything from GPS updates to insurance, to tied down, etc.


But the per mile number can change significantly when your speed at 6500' is 160 knots and FL190 is pushing 200 KTAS. I will be hitting FL210-230 in the next few weeks and am excited to see the performance. 



Posted

Quote: Parker_Woodruff

 

Ward,

Unfortunately I didn't keep down-to-the-penny costs for my M20J. 

 

Also, cost per mile on the M20K is totally dependent on altitude, so an hourly figure is the best way to convert that to $/mi.

 

I think my costs in 2012 dollars will stabilize at about $140-150/hour, as best I can tell. That includes everything from GPS updates to insurance, to tied down, etc.

But the per mile number can change significantly when your speed at 6500' is 160 knots and FL190 is pushing 200 KTAS. I will be hitting FL210-230 in the next few weeks and am excited to see the performance. 

 

Posted

My short trip numbers for the M20K are miserable. Mainly the fuel flow numbers on takeoff do me in (anothe case for the LOP climb)


 


My brother and I flew a cross country of 85 nm each way this past weekend. Total fuel burn? 17 gallons. 


Fuel burn from Longview (GGG) to Lakeland ( LAL) - 52 gal


I totally understand your point, Ward. It just dependS on what the trip will be before I can make a calculation like that. Also, I just worry about the marginal cost of each trip. An annual is going to cost about the same whether the plane flies a few extra hours or not. Same for the insurance, etc. 


Also, in terms of SMPG, I cannot get the M20K to beat what the M20J could do at 9,000'. I can get really close up high. 

Posted

Parker, have you considered a LOP takeoff?  Like, set a FF number and MP that works, such as 14 GPH and 34".  making it a reduced power takeoff.   I amm normally completely against reduced power takeoffs in pistons, but for a short flight might make a heck of a difference in the burn.



I dont know if we could beat your 52 gallon burnoff on that 708 NM flight from KGGG to KLAL.  We are also going 30-40 knots slower.


 

Posted

Quote: jetdriven

Parker, have you considered a LOP takeoff?  Like, set a FF number and MP that works, such as 14 GPH and 34".  making it a reduced power takeoff.   I amm normally completely against reduced power takeoffs in pistons, but for a short flight might make a heck of a difference in the burn.

 

Posted

Quote: Parker_Woodruff

My short trip numbers for the M20K are miserable. Mainly the fuel flow numbers on takeoff do me in (anothe case for the LOP climb)

 

My brother and I flew a cross country of 85 nm each way this past weekend. Total fuel burn? 17 gallons. 

Fuel burn from Longview (GGG) to Lakeland ( LAL) - 52 gal

I totally understand your point, Ward. It just dependS on what the trip will be before I can make a calculation like that. Also, I just worry about the marginal cost of each trip. An annual is going to cost about the same whether the plane flies a few extra hours or not. Same for the insurance, etc. 

Also, in terms of SMPG, I cannot get the M20K to beat what the M20J could do at 9,000'. I can get really close up high. 

Posted

Ward, out of my almost 60 hours in this new bird, I would say during at least 20 of them I have been breathing O2. I absolutely take advantage of what the M20K was designed to do. 


Another 10-15 hours have been in the 10-12k range where the M20K still shines, but the distance didnt allow for flying higher


I'm just pointing out the sheer difference in what any particular flight can mean from a direct expense perspective. 

Posted

I'll make another note and say my cruise numbers are typically 17-18 SMPG in the high teens, but had a headwind/crosswind for a good amount of the quoted flight. Also to blame was an inconvenient altitude change early on due to icing conditions up high. 


http://flightaware.com/live/flight/N252BH/history/20120310/2200Z/KGGG/KLAL


The opposite of this example takes place when I'm fortunate to get a huge tailwind. Dallas to the Memphis area was accomplished in 1 hr 45 min on a burn of 22 gallons or so. 

Posted

MAPA did a comparison between a 201 and 231, performance and cost wise.  In the article they assumed you'd need a top at the halfway point to TBO. I'm not sure that's true depending on your engine management. But with that assumption they calculated the increased cost at about $16/hr more for the K. If you fly high enough to take advantage of the increased speed, it's a wash.

Posted

I'll throw my 2 cents in:


Get the turbo ONLY if your mission profile REQUIRES it.  More to go wrong, more to maintain, more things to watch out for when operating.... if you fly out of the mountain West, by all means, get one.

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