Nice to hear you're getting 260kts out of the -1's up there. I'd thought it be more around 245-250kts. I have the same engines in mine, so hopeful I can come close. But my cabin diff is lower, so probably not get to FL250 very often. Seems like my model is a high teens, low flight levels kinda plane.

An engineer from Cessna saw the fuselage structure opened up in a shop and they could not believe the beefiness of the frame members. It was way stronger at 6 PSI than what they do in Citations for nearly 9 PSI.

The beefiness comes at a cost in increased weight. For as small as the MU2 is, it weighs a lot empty.


The AIN support survey results are not wrong.


The F model is more affected by weight than others due to losing power more quickly as you go higher. This causes a high angle of attack for slower indicated airspeed, and more induced drag. My plane has enough power to keep IAS up and is not as affected by weight. But even so, if I am heavy and go to FL280, the weight does slow you down. I can pick up 10 knots on a long flight sometimes as the fuel burns off.


The 600 hr/3 year inspection is the "big" recurring one. Usually nothing major is found, but the inspection is fairly invasive (interior out, etc).

Last I knew, Chuck charges about $4K for the 600 hr/3 year items, which isn't too bad.


Yes, it does. Keep it up. Get some sim time. Until you've had some sim time, consider your training provisional.


Why not HSI your engines? I think that is still a reasonable thing to do on -1 engines.

Mike C.

As opposed to the unknown of used engines?

If your existing engines are making good power, then that's a good sign. I'd be tempted to stay with engines I know and have operated even if this is marginally more expensive.

The other aspect is that you might not be able to find a pair of suitable engines when you want them. If this is your plan, start looking well in advance, 1-2 years say.

Before you even get to that stage, you need someone to review the logs of your engines and see if you are up against any cycle limits and/or expensive SBs/ADs on HSI. Know where you stand. Do this for any replacement engines as well.

Mike C.

Nobody's going to buy your timed out engines without knowing the condition. Once you open them up you will know whether finishing the hsi or buying used is better

James,

Looking at your panel photo, you are FL250, IAS 162 knots, -17C, about 250 KTAS.

That's feels better than average for an F model, particularly at ISA+18 if I did my math correctly. That's a density altitude of almost 27,000 ft. Do you have faith in the OAT measurement?

Are your engines, by chance, converted with the "Super 1" mod, putting a -5/-6 compressor on a -1 engine?

If not, you might have one of the healthier -1 engine pairs out there.

If so, you definitely want to retain that mod if you can.

You might want to look in the logs books at all the installed STCs and see what they are.

Mike C.

isa+18

I see those temps every trip in the southern hemisphere but have yet to see them up north.

That's awesome James. I wouldn't fret the more speed of the -10s given what you have in the plane, you couldn't go faster for less.

I just got my 100hr done so I am I pace to do over 200 hours this year. I have been surprised how many trips I wouldn't have taken before are no brainers now. Capable planes rule.

Agree that the Mitts is incredibly comfortable in the back too. Passengers are generally blown away by space and smoothness.

If there is a better way to spend money than flying a turbine, I haven't found it yet.

Agreed Anthony. I'm still blown away. Someone pinch me.

Agreed Anthony. I'm still blown away. Someone pinch me.

I'm positive they are not super one conversions. That's supposed to be a 290kt plane. I'd love to do that but have heard its $400k.

Heard the STC paperwork alone is $50K from National. I know of only two Commander 681's who've had the conversion. One is, or was, for sale in Canada just a month ago, the other one lives in Colombia, I think. Rare birds, but great performers.

James, does your AFM say anything regarding a compensation to the factory OAT gauge to get the actual temp? With the Merlin I need to subtract 4* from what I read on the gauge to get actual OAT.

Great question. I'll have to do some research and find out.

Given that, your numbers look pretty good for -1 engines. I don't have a lot of experience flying those, so I could be off, but it feels pretty good. Most F model owners don't fly at FL250 hardly ever because the engine gets wheezy up there, and yours don't seem as wheezy as I would expect.

When you get to HSI, and your engines are making good power, I'd be inclined to keep them and do the HSI. There is a lot of value in knowing the history of your own engines.

There are those who tell you doing the HSI doesn't make economic sense. It's true you won't get back what you put in when you sell. But the flip side is that buying used engines and/or another airplane comes with risks and costs that make keeping your engines worthwhile. If you intend to fly your airplane for a while, the HSI will pay off for you.

Mike C.

Given that, your numbers look pretty good for -1 engines. I don't have a lot of experience flying those, so I could be off, but it feels pretty good. Most F model owners don't fly at FL250 hardly ever because the engine gets wheezy up there, and yours don't seem as wheezy as I would expect.

When you get to HSI, and your engines are making good power, I'd be inclined to keep them and do the HSI. There is a lot of value in knowing the history of your own engines.

There are those who tell you doing the HSI doesn't make economic sense. It's true you won't get back what you put in when you sell. But the flip side is that buying used engines and/or another airplane comes with risks and costs that make keeping your engines worthwhile. If you intend to fly your airplane for a while, the HSI will pay off for you.

Mike C.