Two regional airlines have switched thier Metro fleet over to MT blades and are happy with the results all around. They first had one aircraft switched and went to 2500 hours (IIRC) in order to see what was involved in the overhaul process. When they saw that the hub serviced well they switched more aircraft over. Starts, ground run, climb all better and cruise is at least not negative. Each flight out is at gross so I know they count the weight savings as revenue.

I appreciate all the great comments it has turned out to be a fun project.

Last year I flew a king air 250 a bit. You cannot get a more classic design than a king air but it only attracted 1/5 the attention my commander does.

I don't know if it's the Bob Hoover connection or what, but everybody from corporate pilots to line guys has a comment or a story about the Commanders.

I love it, and I learn something every time I get a chance to hear a Commander story. My wife loves the plane but not the attention it attracts! She wants to get going when we hit our destination!

Awesome! I'll add that the sexy paint design is Steve's original . . . turned out great I think! It takes a bit of bravery to try something different.

Another Garrett question: do feel comfortable operating regularly out of locations that do not have gpu"s?

Also, what about FOD protection operating out of grass and gravel strips-I take it that there is not inertial separator or ice vane?

Yes. GPU is always nicer if you can get it, but battery starts are generally just fine.

If it gets cold, series start (48V start, MU2) works well. I don't know if other types have that feature. The Conquest manual suggests they don't. I wonder how they do in cold weather.

There are also techniques to maximize start success in cold weather without a GPU. Some types allow cross generator starts (MU2 doesn't, Conquest does), which means you need to get the first one going and then the second one is easier.


High wing like Commander and MU2 is not an issue, engine up high away from ground.

Merlin has inlet up, so not an issue generally.

Conquest II would be the worst case, but I don't actually know of any cases of ground based FOD, but that doesn't mean it doesn't happen.

FOD can usually be included in your aircraft hull insurance. Mine does. It is quite rare.

Note that jet engines have direct inlets, so they have pretty much the same FOD risk as the TPE331.

FOD is not something I worry about.

Mike C.

Specific to the commander and starts.

The commander has the ability to use either a series start (48v) or a cross generator/parallel start.

I have been experimenting with both. Both type of starts are well below any temp limits. The series start is a cooler start than a parallel start but that is only for the first engine. Once you select the #1 generator on to assist in starting number 2 that second engine starts cool.

It's just not a problem. Most people seem to end up trying to manage battery life since either a series start or a cross generator/parallel start works well.

I had a battery minder connection built into my plane so I can easily hook up the battery minder and keep the battery up.

Commanders are know for being good on unimproved fields.

Very little weight on nose and big main tires plus the high wing makes it work well on unimproved strips.

My paints to new to try that yet!!!

MT is actually starting 5-blade STC certification right as we speak. They will be test flying it on a German Turbo Commander (probably D-IHSI, is my guess) and doing it through EASA. Once done, it'll port easily over to FAA. I've heard to expect certification late 2017.

BTW, anyone who's interested in Commanders at all, should join the Twin Commander forum, which is growing every day. I'm an admin there and will make sure every BT member feels extra welcome:

http://www.twincommandergroup.com

I've been doing series start for the first engine and then parallel/generator assisted starts for the second engine, and I'm getting good temps and timing on both the starts. I just recently had my batteries replaced during pre-buy/annual and have been doing fine so far without any GPU assistance. I haven't been operating anywhere cold yet, though. I will see if colder starts will be something where I will opt for GPU.

When I've tried parallel start on the first engine, it has been a bit slower to spool up, so I'm opting for a quicker less taxing start on the engines and starter but potentially harder on the batteries. I'd rather stress and replace batteries than engines.

Saw Steve's plane yesterday and it looks even better in person than the photos would suggest...

I used to do a lot of series starts the first few years I had my MU2. Part of that was my inexperience and always wanting my engines to start as fast and cool as possible. But that ate up batteries, starter brushes, start contactors.

I have since used mostly parallel starts in warmish weather, and series when required due to cold, if a GPU isn't around. If a GPU is free to use, I use it, if it costs money, I don't.

I suggest you will have longer battery and brush life if you elect to do parallel starts when the weather is warm. Temps can still be cool if you don't start enrich too much.


How many years/starts did you get from a set? Were they Gill flooded, or Concorde AGM, or something else?

I was doing Gill flooded, about $2400/set. Lasted 2 years, 250 flights, 500 starts, ~60% GPU. Kind of weak. I switched to Concorde AGM, about $4000/set, seem much stronger. Now in my 5th year on the first set, about 500+ flights, 1000+ starts, ~60% GPU, so actually less cost per year/start than the cheaper Gills. In the last two years, I have them on battery minders 24/7 at my FBO (fitted a plug, FBO does it when hangaring my plane). BMs pay for themselves EASILY with turbine batteries costing so much.


Honestly, a series start is often better than a GPU if you have cold conditions. A GPU at 28V won't spin up thick oil like 48V will. If I really need the plane to start in cold, I might forgo a GPU and do series particularly if I don't know the GPU from past starts.

I wonder about the Conquest II which doesn't seem to have series start option. That would worry me.

If you have a really cold soaked engine, you can do a partial start, say to 25% in parallel, shutdown the start, and then put in inlet and tail pipe plugs. Wait about 10 minutes. The heat will diffuse into the oil and heat up the engine. Then remove the plugs an do a series start in full. Now charge the batteries a bit and do a start on the other engine (cross gen if you can). You may have to do the shutdown, let heat soak, restart trick again (which means you should start the right engine first so putting in plugs on the left is safer).

This is an absolute worst case get it started trick. A heated hangar overnight is the absolute best way.


I really don't think the stress is that much more if the start is somewhat slower and you avoid getting near the start temp limit (770C for me, EGT system on -10). The stress on the batteries and starter brushes is extreme for the 48V kick at button press.

Mike C.

Without going through the logs, I'm not sure how many starts the previous owner managed to get out of the prior batteries. I seem to recall them mentioning series starts and pretty good battery life.
I have the Concords now and am at around 40 cycles in under 3 months, which isn't enough to mean anything, yet. I am planning on doing the battery tender hookup, which seems like a good idea.

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Strongly recommended. I believe they will add at least 50% to the battery life.

Mike C.

That's about the time my props will need overhaul. i will be ready to spend some AMUs on something shiny and new.

They will look awesome on a commander!