Steppin' up to a whim.

stratobee

stratobee

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stratobee
You know that time when you're stuck in a foreign hotel room for work and make the mistake of browsing airplane ads late one night when you can't sleep?

You know that time when you happen to come upon a vintage, first generation turboprop that you could just about afford to get into if you sold your current airplane and all your belongings?

You know that time when you call internationally from abroad to check if it's still available - and it is?

You know that time when you fly out to have a look at it and it's just there on the ramp looking at you with those eyes?

You know that time when you call everyone you know who knows anything about anything and ask just "how bad can a TP really be to run?" to try to rationalize it?

You know that time after you've test flown it and all your senses are severely clouded and you mumble "I'll take it" on the rollout?

I'm that guy.

Truth is I was doomed from the minute I saw the ad. Game over, really.


Just (finally) exchanged on my old, old vintage Turbo Commander after 8 months of escrow (long story) and some largish fixes in the shop. I’d been hankerin’ for a turbine for some time, but could never afford one. Until this old bottom of the barrell girl with the sad face came along.

Plane is an old 680V from 1967. First generation turbine Commander, but with the second generation engines. It has the upgraded TPE331-1-151K turbines of the later 681 and 690 model, the so called Century upgrade. TPE331’s are plentiful and relatively cheap as far as turbines go. Early MU-2's had the same engines. A good compromise between the old and the new: don’t have to follow the newer 690’s onerous spar and pressure vessel inspections/AD's, nor do I need to do the gear overhauls every 5 years. But still have the speed of the early 690's.

It’s also a Commander, which is familiar territory for me having owned a piston one before. As much as I loved my Aerostar, I had been missing the SUV utility of a Commander. They're just great all-round aircraft. Take 'em to the Ritz or the mud pit, they're equally at home in both.

The panel is from hell (think 60's submarine), the interior is a pink leather bad dream and it certainly is no one’s idea of a pretty paint scheme, but hey, it’s a turbine! About 1000hrs left on the 5400hr TBO engines. One of them has only got 100 cycles left on the engine (a new ruinous concept), so will need a hot section inspection in about a year.

I’ll be burning 60-65gal/hr, which is double of what I’m burning now. But Jet A1 is also cheaper and I’ll go about 40-50kts faster. Per NM it’s probably the same cost in fuel. Gone are all avgas woes etc. Just what I’ll be saving in oil changes will probably come close to cover one hot section. A friend and owner I know in San Diego operates his for $550-650/hr, which is only about $100-200 more than the Aerostar. I'll call his bamboozling bluff soon, no doubt.

I have no illusions, this will end up costing me more, but that's OK. Maybe a lot more, or maybe just a little more - only time will tell. For the extra spend I should get true all weather capability, turbine reliability, bush capability, speed, long range (1200nm) and no more avgas woes. Hopefully a worthy tradeoff.

The journey begins. Hey, I'll be out of a medical soon enough, so might as well go for it... :loco:
 

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Congratulations! Nothing like the smell of Jet A in the morning! :yes:
I have to agree about the panel, I couldn't find a radio in the picture!! :eek:
 
Thanks!

They're old Gables built ins (top of panel). Don't think the company even exists anymore. Big racks in the avionics bay. Works, but could probably save 1100lbs in useful by replacing them. :D
 
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wow. I applaud your enthusiasm. Hope you enjoy it.
 
Dearest Stratobee,

You suck.

Kindest regards,

Steve
 
Nice, got to fly a 690B a couple times with a former boss, really cool machine - sure it will be a solid transporter and hard to beat the ramp presence, especially with the 331's howling away.

Just a little jealous.

Gimp
 
You poor, dumb, bas...

I meant CONGRATS! Woohoo, new plane is always good. :cheerswine:

I've been following your woe with the Aerostar, hoping I'd get a chance to grab it up, but the reality is I'm not in a position to need it, although I do really want it.

Hoping the new bird is right in your mission and it flies well. Fuggeddabout da panel and gizmos, that changes every 18 months. Good bones are the important part of the calculus. I always lusted after the Commander once I watched Hoover put on his show. Sweet plane. :D

<edit; Hey, in case youse didn't notice -- alla ya prop tips, deh are bent back. MaaaaHaaaaaaahahhaaaaa! Tricky deal. :) >
 
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That is sweet! Take her to the ball one night and out hunting the next day! Not jealous at all, much.
 
Pretty amazing.

The exterior paint is fine. The interior, well, was that the Mary Kay corporate aircraft? I kid, I kid.. I can't say I've ever had that "stuck in a foreign hotel room on business" situation happen to me, but you know what they say about idle hands.

Is this the aircraft that will take you across the Atlantic?
 
stratobee said:
Thanks!

They're old Gables built ins (top of panel). Don't think the company even exists anymore. Big racks in the avionics bay. Works, but could probably save 1100lbs in useful by replacing them. :D
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I pulled the old King Gold Crown stuff out of my 421B, put in a 530W and SL30, the plane lost 70lbs!! :yes:
 
I would love to take this to Europe and visit mum one day. Be a great adventure. Need to install a GPS first and build up some confidence and experience in the machine. And maybe do that hot section inspection as well…;)

Don't know who's idea it was to do the interior in pink leather. All I can say is that it was a bad one!!!

Yeah, I'm thinking of a single GTN 750 eventually, an Aspen PFD, a new NAV/COM (be interesting to see how much weight can be pulled out!) and then probably leaving the rest of it in there. But do it in a new cleaned up panel. Tempted to pull the radar too, although everyone says I shouldn't. I installed UMA-lighting on my old Commander and it literally transformed the old messy post light instruments into this modern looking thing. I don't mind steam and have an easier and quicker time interpreting it than glass, as I have very little experience with that.

Here's how the old one looked after installing the glowing UMA-lights:
 

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stratobee said:
I would love to take this to Europe and visit mum one day. Be a great adventure. Need to install a GPS first and build up some confidence and experience in the machine. And maybe do that hot section inspection as well…;)

Don't know who's idea it was to do the interior in pink leather. All I can say is that it was a bad one!!!

Yeah, I'm thinking of a single GTN 750 eventually, an Aspen PFD, a new NAV/COM (be interesting to see how much weight can be pulled out!) and then probably leaving the rest of it in there. But do it in a new cleaned up panel. Tempted to pull the radar too, although everyone says I shouldn't. I installed UMA-lighting on my old Commander and it literally transformed the old messy post light instruments into this modern looking thing. I don't mind steam and have an easier and quicker time interpreting it than glass, as I have very little experience with that.

Here's how the old one looked after installing the glowing UMA-lights:
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If you're looking for a right seater for the transatlantic flight, give a shout. Aspen is a waste of money, G-600.
 
Pretty friggin' cool, man. As my Dad always said, "No balls, no blue chips!"
 
What's a hot section on one of those engines run?
 
Out of curiosity, what makes the hot side inspection so expensive? Is there a list of expensive items to replace, or is the work insanely expensive? Talking about a no-problems-found HSI.
 
mtuomi said:
Out of curiosity, what makes the hot side inspection so expensive? Is there a list of expensive items to replace, or is the work insanely expensive? Talking about a no-problems-found HSI.
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Depends. If the previous pilots were conscientious in their engine operations and the owner did proper maintenance, it might be inexpensive ($25K) but if the previous guys weren't, get ready to replace a lot of expensive parts.
 
RotorAndWing said:
Depends. If the previous pilots were conscientious in their engine operations and the owner did proper maintenance, it might be inexpensive ($25K) but if the previous guys weren't, get ready to replace a lot of expensive parts.
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How does a low end HSI split up between parts and wrenchturning?
50/50 or whats the rough ratio?
 
TPE331 was the first turbine I flew, I prefer them to PT6s, sometimes spinning the prop get a little old lol.
 
Haven’t gone much with garrets but speaking from the perspective of a PT6, big picture should be analogous.

The HSI isn’t an overhaul. As the name implies, it’s an inspection. There are different inspection criteria compared to overhaul, it’s less strict for an HSI. For example, non-rotating parts may have some stress-relieving cracks and be deemed OK. Some erosion of ceramics and some corrosion are also acceptable as long as it’s not affecting the integrity of the underlying material. There are some guidelines for making these calls, but there’s also some personal judgment involved.

If you are doing the HSI based on a schedule and not because of a performance loss, then it might not be too much $$. Best case, you’d get by with cleaning and measuring, changing some turbine shroud segments and some grinding for clearance between the segment and the blade tips. You might get through this best case scenario for $30k and change. OTOH if you get all-new combustion liners, vane rings, turbine blades, etc, you’re going to be pushing $110k.

Moral of the story, watch your ITT and torque limits, and keep up with your fresh water washes. And pray.
 
JHW said:
Haven’t gone much with garrets but speaking from the perspective of a PT6, big picture should be analogous.

The HSI isn’t an overhaul. As the name implies, it’s an inspection. There are different inspection criteria compared to overhaul, it’s less strict for an HSI. For example, non-rotating parts may have some stress-relieving cracks and be deemed OK. Some erosion of ceramics and some corrosion are also acceptable as long as it’s not affecting the integrity of the underlying material. There are some guidelines for making these calls, but there’s also some personal judgment involved.

If you are doing the HSI based on a schedule and not because of a performance loss, then it might not be too much $$. Best case, you’d get by with cleaning and measuring, changing some turbine shroud segments and some grinding for clearance between the segment and the blade tips. You might get through this best case scenario for $30k and change. OTOH if you get all-new combustion liners, vane rings, turbine blades, etc, you’re going to be pushing $110k.

Moral of the story, watch your ITT and torque limits, and keep up with your fresh water washes. And pray.
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How much are these shroud segments to replace? Is the HSI really 500-or-so man hours to complete?
I'm just trying to get my head around turbine maintenance prices.
 
mtuomi said:
How much are these shroud segments to replace? Is the HSI really 500-or-so man hours to complete?
I'm just trying to get my head around turbine maintenance prices.
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I'm not sure on specific parts pricing anymore. The numbers I quoted above are for a 3rd party to do it all. We have -20's and spares are hard to get. We've been living off a local shed full of parts. 500 man*hours seems pretty high to me.
 
JHW said:
Haven’t gone much with garrets but speaking from the perspective of a PT6, big picture should be analogous.

The HSI isn’t an overhaul. As the name implies, it’s an inspection. There are different inspection criteria compared to overhaul, it’s less strict for an HSI. For example, non-rotating parts may have some stress-relieving cracks and be deemed OK. Some erosion of ceramics and some corrosion are also acceptable as long as it’s not affecting the integrity of the underlying material. There are some guidelines for making these calls, but there’s also some personal judgment involved.

If you are doing the HSI based on a schedule and not because of a performance loss, then it might not be too much $$. Best case, you’d get by with cleaning and measuring, changing some turbine shroud segments and some grinding for clearance between the segment and the blade tips. You might get through this best case scenario for $30k and change. OTOH if you get all-new combustion liners, vane rings, turbine blades, etc, you’re going to be pushing $110k.

Moral of the story, watch your ITT and torque limits, and keep up with your fresh water washes. And pray.
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That,

Doing trends also helps.

Not sure about the commander, but some of the 331s have SRL and TTL making it tuff to over TRQ or temp outside of startup.
 
JHW said:
I'm not sure on specific parts pricing anymore. The numbers I quoted above are for a 3rd party to do it all. We have -20's and spares are hard to get. We've been living off a local shed full of parts. 500 man*hours seems pretty high to me.
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Would be cool to hear what the actual breakdown would be, and how many hours really it takes. My experience with turbine engines is that I've seen one once, but I find it difficult to believe it would take many hundreds of hours to dis/reassemble one.

Is there a point, when it actually would be cheaper to pay for an A&P to work for you full time, than to pay the rates shops charge?
 
mtuomi said:
Would be cool to hear what the actual breakdown would be, and how many hours really it takes. My experience with turbine engines is that I've seen one once, but I find it difficult to believe it would take many hundreds of hours to dis/reassemble one.

Is there a point, when it actually would be cheaper to pay for an A&P to work for you full time, than to pay the rates shops charge?
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you have to have the right piece of paper and there is some tooling. It's not just a truck-bed A&P job. It might also vary by country. For example I have a maintenance engineer license and I can do the phase inspections on the king air, I can hang a prop, I can remove and install an engine, i can do many engine repairs. But i can't do the HSI or engine overhaul and reset the cycles
 
I wonder if they work the same way an A&P I recently saw working does.
He spent 75% of the time walking from one end of the hangar to the other, picking tools from his toolbox he would not move next to the plane. One at the time, usually the wrong one first time.

Are the HSIs mandatory in P91, or like overhauls with pistons?
 
mtuomi said:
Are the HSIs mandatory in P91, or like overhauls with pistons?
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here, mandatory

in FAA-land, that is a subject of lots of spirited debate

IMO though you can't push it too long or you're just going to be buying more expensive parts. The $$ at risk from stretching the overhaul on an horizontally opposed recip is almost nil in comparison. At worst you'll trash a crank and need a new one, that's $10-15K.

In the case of our old king air here, I'm pushing the majority owner to retire it at the end of this year. The orphaned engines are just one of many issues. However, it looks like they'll still have some cycles left so I'll make you a smokin hot deal of you want to dip your toe in the water:wink2:
 
Yeah, HSI's vary. This one is assumed by the experts to be in the $40-50K region.

For some reason they put used turbine wheels in with fewer cycles at last HSI, no doubt to save money. My 3rd wheel only has 137 cycles left. That's not the same as hours, but one cycle counts as a full start and a shutdown. So depending on how long you fly, that can be very short or a very long time. The Garretts come with three turbine wheels - the 3rd wheel is the biggest, but it also runs the coolest so is relatively cheap and normally has less damage. The 1st stage one is the expensive one. Think a new one from Honeywell runs around $14K for wheel alone. Most likely they'll find stator rings that need replacing and some other stuff as well. If all three are bad, it gets expensive. But as with everything in aviation, there are ways to skin a cat. You can get used turbine wheels that are serviceable and put them in.

Also, just because you open up a turbine and replace a wheel does not mean you have to hot section it. But I quote "If we do see something obvious, or a part number affected by an AD, then it might have to be a HSI after all, so always be prepared for that".

The Commander Garretts run cooler than the MU-2's. My temp limit is 575, which is almost 70 degrees cooler than the MU-2's, so in theory should be in better shape at HSI. But not sure if the MU-2's sample the temp at some other stage - might be the case they run exactly as hot in the core.
 
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stratobee said:
You know that time when you're stuck in a foreign hotel room for work and make the mistake of browsing airplane ads late one night when you can't sleep?

You know that time when you happen to come upon a vintage, first generation turboprop that you could just about afford to get into if you sold your current airplane and all your belongings?

You know that time when you call internationally from abroad to check if it's still available - and it is?

You know that time when you fly out to have a look at it and it's just there on the ramp looking at you with those eyes?

You know that time when you call everyone you know who knows anything about anything and ask just "how bad can a TP really be to run?" to try to rationalize it?

You know that time after you've test flown it and all your senses are severely clouded and you mumble "I'll take it" on the rollout?

I'm that guy.

Truth is I was doomed from the minute I saw the ad. Game over, really[/QUOTE

Been there, done that, doin it again. Barnstormers, TradeaPlane etc. could officially be classified as Porn. Best of luck with your project. Post us a pic of you pouring a glass of tea will barrel rolling it when you're done.
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stratobee said:
Yeah, HSI's vary. This one is assumed by the experts to be in the $40-50K region.

For some reason they put used turbine wheels in with fewer cycles at last HSI, no doubt to save money. My 3rd wheel only has 137 cycles left. That's not the same as hours, but one cycle counts as a full start and a shutdown. So depending on how long you fly, that can be very short or a very long time. The Garretts come with three turbine wheels - the 3rd wheel is the biggest, but it also runs the coolest so is relatively cheap and normally has less damage. The 1st stage one is the expensive one. Think a new one from Honeywell runs around $14K for wheel alone. Most likely they'll find stator rings that need replacing and some other stuff as well. If all three are bad, it gets expensive. But as with everything in aviation, there are ways to skin a cat. You can get used turbine wheels that are serviceable and put them in.

Also, just because you open up a turbine and replace a wheel does not mean you have to hot section it. But I quote "If we do see something obvious, or a part number affected by an AD, then it might have to be a HSI after all, so always be prepared for that".

The Commander Garretts run cooler than the MU-2's. My temp limit is 575, which is almost 70 degrees cooler than the MU-2's, so in theory should be in better shape at HSI. But not sure if the MU-2's sample the temp at some other stage - might be the case they run exactly as hot in the core.
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A lot of the big $ I've noticed is in blades, especially when you need 100 blades that run about $800 each. These are in mid sized turbofans tho, not turboshafts
 
Well, a little update.

Getting near the end of the fixes now - it's been a long year with the mechanic (and not flying much since I sold old plane). I have it with an 80 year old Commander expert who works slowly and tries to source better used parts rather than splash on new (unless we have to). A policy we both agree upon. The downside is it takes forever. Cheap, fast and good - pick two, right?

For those curious about turbines in general, I'll try to include some prices just to give you an idea of the costs involved.

1. Fuel nozzles had not been spray tested/cleaned as they should each 400hrs, so they were over 800hrs when we pulled them. Sloppy from previous owner. In itself a cheap overhaul, but the removal revealed bad and unserviceable fuel lines. That was a $5000 item to replace.

2. That also revealed that starter generators on both engines should probably be overhauled, even though they were within limits. I didn't want to risk having any troubles with those as the Garretts are power hungry, so off they went to Tulsa. Was $2K/piece or $4K in total.

3. Front windscreens were pretty scratched (acrylic alcohol window on these early models). New ones would have been $11K, but we sent them for reconditioning and overhaul at a company that specializes in that. They look like new. $3K instead. Much better.

4. Both exhausts were cracked and we wasted a long time trying to find serviceable ones, but in the end just had them replace a portion and re-weld. Should have done that from the start. $3600.

5. Cabin was leaking pressure like a sieve. Turned out all windows except one was leaking! Resealed. But, just to be on the safe side I replaced the column and pedal boots with a new kit (floor is pressure vessel on the earlier Commanders, not the outer hull). Kit was just shy of $4000.

6. Batteries had dead cells and didn't accept charge well. Again, Garretts needing a lot of power to start up, this had to be replaced. Batteries for turbines are no joke in price - was over $3K for two new Gills! The fancy Concorde dry cell ones that last longer, ware about $2.5K each, but I decided to stick with the Gills. Might swap next time around as everyone says they're better and lasts more than twice a s long.

7. Removal of aft gear door STC. Will decrease speed by about 5kts, but it simplifies and speeds up the gear deployment. $1K for STC.

Well there you have it. Warts and all. On top of this there's been lots of smaller stuff. Phase inspections (annual), fixes, cleaning all filters, hydraulic leak fixes, jammed trim cables, bad brake lines, etc. As you can see, not excessive compared to a legacy piston twin, although in the upper bracket for sure. In total we're up to $42K with labor as it stands. I'm sure it will be another $10K before I get her sorry a** out of there. And god knows what else will turn up as I start flying her...:rolleyes:

Slumming it in the turboprop world - so you don't have to! :D
 
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stratobee said:
Well, a little update.
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Ah, you bring back some memories. I got a job flying a 690B in 1981. My checkout was a real ordeal--learning to taxi the confounded thing. The rudder pedals have toe brakes that also work the hydraulic steering system. You apply pressure and nothing happens until you apply too much and the brake grabs instead, jerking the plane to the side. Then the wind catches the big rudder and feeds back the rudder pedal causing unintended steering when your ankle refuses to bend backward.

On the final landing, the "L-Chip" light came on during the rollout. I asked the departing pilot what that meant. He said something like, "I don't know, but the only other time I saw it the bill came to $37,000. Good luck, see ya." My first flight was a ferry flight to the maintenance shop, shooting a real honest 200 & 1/2 approach. Lucked out on the cause--only $3,000 to replace a worn washer.

Heck of a plane though. Lots and lots of baggage area and an honest 260 KTAS.

dtuuri
 
Love the prop Commanders. I was working on buying an L-26B, which was the military version of the 560A. It was dirt cheap, and in decent shape other than a few undocumented repairs that I would correct. The only thing that scared me off that a/c, was the fact that it had never been able to go past 445 hours before having a right engine failure. In going thru the logbooks, between 404 and 445 hours, it consistently ate a right engine. According to the logs, it was on it's tenth right engine at that time. Once it shed the prop and the engine nose case in flight and twice it blew jugs and cowling sections off in flight. With that much history and the current right engine on it at 430 hours since major, I chickened out and passed.
 
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