Ted
The pilot formerly known as Twin Engine Ted
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- Oct 9, 2007
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iFlyNothing
On January 30th, 2018 Cloud Nine took delivery of our "new" aircraft - a 1972 MU-2. I discussed the purchase in this thread.
Although not yet at exactly a year with the plane, we had it for almost all of 2018 did a lot with the plane. The following major events occurred:
- Getting initial insurance
- Delivery (that's what matters most, right?)
- 14 CFR Part 91 Subpart N mandated training (so that I could fly it)
- Hot section on the right engine
- First 100/200 hour (annual) under my care
- Second 100-hour under my care (because I flew it on a lot of mission)
I ended up flying a total of 12 Cloud Nine missions saving 374 homeless pets and just over 216 hours total on flights that spanned from coast to coast, and as far as Puerto Rico and Costa Rica. It's been a fun year.
Going in, I had anticipated that costs per mile would be similar to the 414. Thus far, I've found that to be fairly accurate, but it depends on how you look at it. The 100/200, second 100 hour, and then adding an EGT harness that needed to get replaced bring the hourly maintenance cost to around $150/hr. That is significantly cheaper than the 414 was, and I am now taking it to a Mitsubishi authorized service center rather than using a small private shop. One of the side effects of this has been shorter duration shop visits and thus more time available to fly.
I am obviously not including the hot section in the above numbers, but I don't think it's entirely reasonable to as that's a once per 1800 hours (per engine) expense, and your resale value changes significantly with your engine times (both SMOH and SHSI). That came out to just under $70k, but that was a really expensive hot section as a lot of items needed to get replaced. It was also the engine's second hot section, so not entirely surprising. The 414's engines were going to cost $70k to overhaul for the pair, so in terms of a short term expense it came out about the same.
As I've built hours and comfort in the plane, I've gotten to know it and learned a few things.
Although these engines are only rated to sea level and 75F, they perform a lot better than that. The EGT limit for takeoff is higher than max cruise or "max continuous" (which has a vague description in the POH other than "for emergency use"). I haven't had issues getting max torque or close to it. That's a good thing.
Originally I had expected to do most of my takeoffs as flaps 5 and most of my landings as flaps 20. Options for takeoff are flaps 5 or flaps 20, and options for landing are flaps 20 or flaps 40. In training my instructor said that he typically did and recommended flaps 20 for takeoff and landing, and after doing a couple flaps 5 takeoffs and flaps 40 landings I agreed that seemed logical. With some hours in the plane, I've expanded that a bit more. Flaps 40 is great if you have altitude you need to lose, as it basically turns the airplane into an elevator. I've used it a few times in VMC conditions for that reason, but I would never use it in IMC. I've become friends with the man who flew this plane for 25 years, and he always did flaps 40 landings, but was based at a 3200 ft strip. In those days the guidelines for flaps 40 were also different and allowed for slower speeds coming in. They changed the guidelines because of some crashes, and I can see why. There's a lot of drag, and an engine failure when slow with flaps 40 I don't see as being something you can power out of unless lightweight and performance was in your favor. Flaps 20 is more logical in my opinion.
For takeoffs, I've started playing around with flaps 5 some more and am finding I like those better when relatively lightweight and cold, but it definitely eats up more runway to do. I normally take off from a 6800 ft runway though, so no big deal. What's nice about flaps 5 is that you have less drag and a bit more speed in the event of an engine failure shortly after takeoff, as rotation speeds are roughly 7 KIAS faster for the same weight. I'm still evolving my personal preferences.
For climb, I initially did 160 KIAS and went from 100% RPM down to 96% RPM passing 9,000 ft, which is where the manual says you should for engine efficiency. I've switched from doing that to 100% RPM for climb and Vy, which varies with altitude and weight but is roughly 135-155 KIAS. This ends up reducing my time to climb noticeably, which also reduces my total fuel burn.
Oh, right, fuel burn. And speed. Initially I'd figured around 270 KTAS on speed. The plane will do that and more if I really want to push it, but doing so requires being in the hight teens or very low flight levels and burning on the order of 70 GPH. For the most part I'm cruising at FL200-250 (ceiling is FL250) and that is 52-60 GPH combined for 250-260 KTAS depending on weight. I also fly at 96% RPM in cruise almost always as that burns about 4 GPH less combined for not much speed loss, is quieter, and also is cooler on the hot section (which should increase life). The exception to this is if 100% RPM will get me to a higher altitude than I could get at 96% RPM (due to the extra power) and that somehow benefits me for winds/efficiency/etc. Then I'll run at 100% RPM until I burn off enough fuel to get 160 KIAS or better at 96% RPM. 160 KIAS is best efficiency speed. One thing that's nice is that even with a stiff headwind, I almost never see under 200 KTS ground speed. It has to be a really bad wind for that. So even with a bad wind, I'm still making good time.
I generally aim for 500C EGT, which is roughly 20C below the max cruise limit in general. The plane seems happy there. With the winter winds I've had a couple times where I've had to fly in the mid teens and the fuel burns go up significantly, but those have been pretty rare. Best ground speed so far was over 400 KTS in a dive with a 100 kt tailwind.
I never found the fuel costs to be less for the MU-2 vs. the 414, but I also was burning a lot less fuel with the 414 than most Twin Cessna owners, so that wasn't a surprise. A few years ago, Jet A was way, way cheaper than 100LL. That's less the case now but when you factor in the extra speed and better maintenance costs, the average cost per mile is still less than the 414. In the end, I've shaved about 25% off of block times vs. the 414. A trip that took 16 hobbs hours in the 414 takes 12 in the MU-2, almost exactly.
My personal minimum for runways is still 4000 ft, which is what I set for myself after training. Can the plane do shorter? Absolutely. Could I? Sure, I proved that in training. But, things happen quickly with rotation and landing speeds around 100 KIAS and I just don't think that the risk is worth the benefit. Operationally it's not an issue, either. The only runway I would have liked to fly into that's <4,000 ft is Gaston's, and if we really decided to go we can land at Mountain Home and thumb a ride.
For the first 50 hours or so I did almost all my trips with a co-pilot along, and developed a "Co-Pilot SOP" that basically said "This is what will kill us, make sure I don't do any of it." I found that very helpful as initially got used to the plane. I still find it nice to have a co-pilot along since nobody's perfect, although I'm comfortable flying the plane solo.
I tell people that it's basically two different planes - the plane above 160 KIAS and the plane below. You really feel the difference at lower speeds and it doesn't feel like a normal airplane because of the reduced roll authority of the spoilers. My wife's first impression flying right seat going into Houston with it at 130 KIAS (a normal approach speed, if anything a hair fast) was "This is too slow." It feels that way and low speeds take getting used to. That said it's still an honest airplane. Energy management is important as you can easily blast into the pattern at 230 KIAS. The big thing is that speed doesn't bleed off very quickly until you hit about 130 KIAS, and then it bleeds off very quickly so it requires attention. This is what killed Pascal (along with a whole string of bad decisions leading up to it) when he was bleeding off speed and then found himself below 100 KIAS at flight idle with flaps and gear out with his head looking at the clouds instead of at the instruments.
I have a great deal of respect for the plane, but the basic flying of it is not complex and the flows/checklists are straightforward. I check the "6 things that will kill me" before takeoff (3 trim settings, flaps, condition levers, and bleed air), flaps and gear have their appropriate speeds and easy flow on those - <175 flaps 5, <160 gear, <140 flaps 20. Flaps 40 requires <120 which is not particularly comfortable to be adding all that drag and it needs a lot of power added back in.
It's impossible to get this plane out of aft CG. The problem is actually forward CG. The W&B envelope reduces max takeoff and landing weights as your CG goes forward, so my issue is typically having the CG aft enough and that is typically what restricts my fuel load. That said, the plane is efficient enough and carries enough (366 gallons) that it's rarely an issue. For the long trips I have to make a stop, but I've eliminated many fuel stops I had to make with the 414, which is part of why it saves so much time.
@James_Dean had issued a challenge between the ChickenHawk Express and the MU-2. We haven't done it yet, but my thoughts are:
- The MU-2 will win a brick approach, hands down
- The MU-2 will win on MPG
- The 425 will win on outright speed, being a Blackhawk, as well as time to climb
- The 425 will win on cabin and cockpit comfort, hands down
Ultimately, it's a great plane and very rewarding, and most importantly a great fit for Cloud Nine's mission. I have always loved MU-2s, and it was a long time dream to get to fly one. The reality has been just as good as I'd imagined.
Although not yet at exactly a year with the plane, we had it for almost all of 2018 did a lot with the plane. The following major events occurred:
- Getting initial insurance
- Delivery (that's what matters most, right?)
- 14 CFR Part 91 Subpart N mandated training (so that I could fly it)
- Hot section on the right engine
- First 100/200 hour (annual) under my care
- Second 100-hour under my care (because I flew it on a lot of mission)
I ended up flying a total of 12 Cloud Nine missions saving 374 homeless pets and just over 216 hours total on flights that spanned from coast to coast, and as far as Puerto Rico and Costa Rica. It's been a fun year.
Going in, I had anticipated that costs per mile would be similar to the 414. Thus far, I've found that to be fairly accurate, but it depends on how you look at it. The 100/200, second 100 hour, and then adding an EGT harness that needed to get replaced bring the hourly maintenance cost to around $150/hr. That is significantly cheaper than the 414 was, and I am now taking it to a Mitsubishi authorized service center rather than using a small private shop. One of the side effects of this has been shorter duration shop visits and thus more time available to fly.
I am obviously not including the hot section in the above numbers, but I don't think it's entirely reasonable to as that's a once per 1800 hours (per engine) expense, and your resale value changes significantly with your engine times (both SMOH and SHSI). That came out to just under $70k, but that was a really expensive hot section as a lot of items needed to get replaced. It was also the engine's second hot section, so not entirely surprising. The 414's engines were going to cost $70k to overhaul for the pair, so in terms of a short term expense it came out about the same.
As I've built hours and comfort in the plane, I've gotten to know it and learned a few things.
Although these engines are only rated to sea level and 75F, they perform a lot better than that. The EGT limit for takeoff is higher than max cruise or "max continuous" (which has a vague description in the POH other than "for emergency use"). I haven't had issues getting max torque or close to it. That's a good thing.
Originally I had expected to do most of my takeoffs as flaps 5 and most of my landings as flaps 20. Options for takeoff are flaps 5 or flaps 20, and options for landing are flaps 20 or flaps 40. In training my instructor said that he typically did and recommended flaps 20 for takeoff and landing, and after doing a couple flaps 5 takeoffs and flaps 40 landings I agreed that seemed logical. With some hours in the plane, I've expanded that a bit more. Flaps 40 is great if you have altitude you need to lose, as it basically turns the airplane into an elevator. I've used it a few times in VMC conditions for that reason, but I would never use it in IMC. I've become friends with the man who flew this plane for 25 years, and he always did flaps 40 landings, but was based at a 3200 ft strip. In those days the guidelines for flaps 40 were also different and allowed for slower speeds coming in. They changed the guidelines because of some crashes, and I can see why. There's a lot of drag, and an engine failure when slow with flaps 40 I don't see as being something you can power out of unless lightweight and performance was in your favor. Flaps 20 is more logical in my opinion.
For takeoffs, I've started playing around with flaps 5 some more and am finding I like those better when relatively lightweight and cold, but it definitely eats up more runway to do. I normally take off from a 6800 ft runway though, so no big deal. What's nice about flaps 5 is that you have less drag and a bit more speed in the event of an engine failure shortly after takeoff, as rotation speeds are roughly 7 KIAS faster for the same weight. I'm still evolving my personal preferences.
For climb, I initially did 160 KIAS and went from 100% RPM down to 96% RPM passing 9,000 ft, which is where the manual says you should for engine efficiency. I've switched from doing that to 100% RPM for climb and Vy, which varies with altitude and weight but is roughly 135-155 KIAS. This ends up reducing my time to climb noticeably, which also reduces my total fuel burn.
Oh, right, fuel burn. And speed. Initially I'd figured around 270 KTAS on speed. The plane will do that and more if I really want to push it, but doing so requires being in the hight teens or very low flight levels and burning on the order of 70 GPH. For the most part I'm cruising at FL200-250 (ceiling is FL250) and that is 52-60 GPH combined for 250-260 KTAS depending on weight. I also fly at 96% RPM in cruise almost always as that burns about 4 GPH less combined for not much speed loss, is quieter, and also is cooler on the hot section (which should increase life). The exception to this is if 100% RPM will get me to a higher altitude than I could get at 96% RPM (due to the extra power) and that somehow benefits me for winds/efficiency/etc. Then I'll run at 100% RPM until I burn off enough fuel to get 160 KIAS or better at 96% RPM. 160 KIAS is best efficiency speed. One thing that's nice is that even with a stiff headwind, I almost never see under 200 KTS ground speed. It has to be a really bad wind for that. So even with a bad wind, I'm still making good time.
I generally aim for 500C EGT, which is roughly 20C below the max cruise limit in general. The plane seems happy there. With the winter winds I've had a couple times where I've had to fly in the mid teens and the fuel burns go up significantly, but those have been pretty rare. Best ground speed so far was over 400 KTS in a dive with a 100 kt tailwind.
I never found the fuel costs to be less for the MU-2 vs. the 414, but I also was burning a lot less fuel with the 414 than most Twin Cessna owners, so that wasn't a surprise. A few years ago, Jet A was way, way cheaper than 100LL. That's less the case now but when you factor in the extra speed and better maintenance costs, the average cost per mile is still less than the 414. In the end, I've shaved about 25% off of block times vs. the 414. A trip that took 16 hobbs hours in the 414 takes 12 in the MU-2, almost exactly.
My personal minimum for runways is still 4000 ft, which is what I set for myself after training. Can the plane do shorter? Absolutely. Could I? Sure, I proved that in training. But, things happen quickly with rotation and landing speeds around 100 KIAS and I just don't think that the risk is worth the benefit. Operationally it's not an issue, either. The only runway I would have liked to fly into that's <4,000 ft is Gaston's, and if we really decided to go we can land at Mountain Home and thumb a ride.
For the first 50 hours or so I did almost all my trips with a co-pilot along, and developed a "Co-Pilot SOP" that basically said "This is what will kill us, make sure I don't do any of it." I found that very helpful as initially got used to the plane. I still find it nice to have a co-pilot along since nobody's perfect, although I'm comfortable flying the plane solo.
I tell people that it's basically two different planes - the plane above 160 KIAS and the plane below. You really feel the difference at lower speeds and it doesn't feel like a normal airplane because of the reduced roll authority of the spoilers. My wife's first impression flying right seat going into Houston with it at 130 KIAS (a normal approach speed, if anything a hair fast) was "This is too slow." It feels that way and low speeds take getting used to. That said it's still an honest airplane. Energy management is important as you can easily blast into the pattern at 230 KIAS. The big thing is that speed doesn't bleed off very quickly until you hit about 130 KIAS, and then it bleeds off very quickly so it requires attention. This is what killed Pascal (along with a whole string of bad decisions leading up to it) when he was bleeding off speed and then found himself below 100 KIAS at flight idle with flaps and gear out with his head looking at the clouds instead of at the instruments.
I have a great deal of respect for the plane, but the basic flying of it is not complex and the flows/checklists are straightforward. I check the "6 things that will kill me" before takeoff (3 trim settings, flaps, condition levers, and bleed air), flaps and gear have their appropriate speeds and easy flow on those - <175 flaps 5, <160 gear, <140 flaps 20. Flaps 40 requires <120 which is not particularly comfortable to be adding all that drag and it needs a lot of power added back in.
It's impossible to get this plane out of aft CG. The problem is actually forward CG. The W&B envelope reduces max takeoff and landing weights as your CG goes forward, so my issue is typically having the CG aft enough and that is typically what restricts my fuel load. That said, the plane is efficient enough and carries enough (366 gallons) that it's rarely an issue. For the long trips I have to make a stop, but I've eliminated many fuel stops I had to make with the 414, which is part of why it saves so much time.
@James_Dean had issued a challenge between the ChickenHawk Express and the MU-2. We haven't done it yet, but my thoughts are:
- The MU-2 will win a brick approach, hands down
- The MU-2 will win on MPG
- The 425 will win on outright speed, being a Blackhawk, as well as time to climb
- The 425 will win on cabin and cockpit comfort, hands down
Ultimately, it's a great plane and very rewarding, and most importantly a great fit for Cloud Nine's mission. I have always loved MU-2s, and it was a long time dream to get to fly one. The reality has been just as good as I'd imagined.
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