One of the problems with the Ultra has traditionally been the expensive high turbine blades. This problem has been resolved with an FAA approved process to add blade length and overhaul the blades for under $500 per blade. This is a big deal for the Ultra and all of the Legacy Citation series. I am sending in a set next week and will report back.

With the soon to be approved STEC autopilot, it will also soon be possible to de-Honeywell these airplanes.

An Ultra offers CJ3 performance for 20 cents on the dollar.

See Attached.

Wow this is great news. Ultra prices will probably go up because of this.

This could be bad news for the rest of the fleet. It means the Citation V might not be the only model worth having.

Nice, but the Stec most likely will never be approved for the Ultra for the same reason Jet Tech won't add it the Ultra to their STC. The Honeywell doesn't play well with others.

The Honeywell Primus 1000 system has the autopilot integrated into the display system. Thus you CANNOT install a Garmin EFIS panel because removing the Primus 1000 removes the autopilot. So the Ultra (and Bravo and Encore which also have Primus 1000) are condemned to carrying around the Primus 1000 system. JetTech can't add the Ultra to their STC because they can't remove the autopilot.

Unless there is an STC autopilot.

Then, and only then, you can remove the ENTIRE Primus 1000 system, display and autopilot, and replace it with Garmin and the new autopilot.

So it no longer will matter how Honeywell plays with others, they won't exist at all on an Ultra with a Garmin EFIS and an STEC autopilot.

Anybody with a Primus 1000 airplane is just begging to ditch the system. Failure prone, expensive to repair, heavy, uses a lot of power, generates heat. The displays are CRTs, big glass tubes! This is why JetTech is keen on getting an STC autopilot, it opens up a whole fleet of other airplanes to get Garminized, adn why they provided STEC an airplane to do the STC certification.

As to STEC 5000 autopilot, I was at SnF and stopped by the Genesys booth. Here is what I was told.

They say the install kit will be $65K. STC for the AP will be owned by Genesys. Requires G600/G700 TXi panels, but doesn't have to be JetTech STC. Expected FAA approval June/July this year. Will cover the entire legacy series, 500, 501, 550, 551, 550 Bravo, S550, 560 V, 560 Ultra, 560 Encore. Will not cover, oddly, 560 Encore+ (which has ProLine 21).

Will need separate annunciator panel (AP status not shown on EFIS). Will do VNAV. Has 4 servos (pitch, pitch trim, roll, yaw). Operates from 28 VDC.

Now we wait to see how much of the above comes to past.

Mike C.

Too late, the V is already out of reach.

Mike C.

I assume this fix is for blades with excessive tip erosion. Is that the only thing that causes these blades to fail an inspection? I would think they have a creep inspection too don't they? How does this fix address creep? Do they receive a new coating after the tip repair? Are Ultra HPT blades single crystal?

What are you talking about? This is GREAT news! It means I might be able to afford a V in 5 years when I meet the turbine time requirement for the SPE.

I doubt it. The value of this mod will be determined by what percentage of the blades it can save versus not. I have no idea what that success rate will be.


Maybe. They are definitely made from fancier stuff than the other blades since they don't last as long and cost a heck of a lot more.

The HT blades in my JT15D-5A engines are 3055021-01, $3350 list, $2345 after discount, each. There are 71 per engine, $166K per engine for a full set. They last maybe 5000 hours, so $33/hour/engine. The JT15D-5D (in the Ultra) are near $100/hour/per engine due to short live and higher cost.

If an Ultra can come with full Garmin panels and new AP, and the JT15D-5D HT blades can be a lot cheaper to maintain, it would be a very nice airplane! Those two limitations kept me away.

Mike C.

That’s correct, they are definitely single Crystal and yes they get recoated after this lengthening procedure. I would say the main reason blades fail other than impact damage fail is due to sulfidation. It really is critical to do. Compressor washes once in a while.

Jet Tech owns an ultra as a personal airplane. I think it will happen.

I doubt it. The value of this mod will be determined by what percentage of the blades it can save versus not. I have no idea what that success rate will be.


Maybe. They are definitely made from fancier stuff than the other blades since they don't last as long and cost a heck of a lot more.

The HT blades in my JT15D-5A engines are 3055021-01, $3350 list, $2345 after discount, each. There are 71 per engine, $166K per engine for a full set. They last maybe 5000 hours, so $33/hour/engine. The JT15D-5D (in the Ultra) are near $100/hour/per engine due to short live and higher
Mike C.

Single crystal? Probably not. A SC blade casting (for even a small blade) could easily be more than $1500 from the foundry. Add in machining, finishing, overhead profit, etc and a SC blade this size would be more in the $5K range. Most likely they are directionally solidified if PWC certified an upgrade. Otherwise they are equiaxed.

The photo in the original post shows a solid cast blade with no thermal barrier coating. Please enlighten me if different than the photo[/quote]

I'm highly interested in how these blades are made, teach the group please. These are $7K a piece retail.

Single crystal? Probably not. A SC blade casting (for even a small blade) could easily be more than $1500 from the foundry. Add in machining, finishing, overhead profit, etc and a SC blade this size would be more in the $5K range. Most likely they are directionally solidified if PWC certified an upgrade. Otherwise they are equiaxed.

The photo in the original post shows a solid cast blade with no thermal barrier coating. Please enlighten me if different than the photo[/quote]

Isn’t directionally solidified saying the same as equiaxed? I always thought single Crystal was a misnomer for that process. Although you have to admire all the talent that developed those environmentally controlled molds. Superalloys is the term I heard thrown around. Just align the “grains” of the material, should be easy right? Just like landing on the moon.

Here's a very brief explanation of turbine blade casting types. (By design this will be oversimplified to keep me from getting carpal tunnel damage)

In order of performance (lowest to highest):

Equiax (EQ) castings are the "conventional" casting one would normally envision. Molten metal is poured into the blade mold and cooled (either by air or sometimes with a water jacket surround the mold). The resulting blade has it's metal grains dispersed along all directions within the blade. If the casting is sectioned, a sample mounted and polished, the resulting microscopic view shows small grains everywhere. Loads applied to the metal are transferred from each grain to the next (at the microscopic level), with the strength of the material being determined by the deformation that occurs between the grains (primarily) and within the grains themselves (secondarily).

Grain boundaries also are prone to inter-granular oxidation and corrosion, which significantly weaken the metal. Inter-granular corrosion is a constant threat as the combustion products that turbine blades encounter are highly oxidized gasses that will attack the base metal (one of many reasons one typically finds turbine blades have surface treatments such as ceramic thermal barrier coatings, especially in the high pressure turbine area)

Directionally Solidified (DS) blades attempt to limit grain boundaries to a relative few aligned along the blade's primary stress axis, usually radially outward along the blade span, (there are a few notable exceptions, mostly military applications, and as far as I know, still classified). Before the molten metal gets to the fir tree, (where the blade attaches to the disk) it travels through what is known as a chill block, then continues into a spiral tube known as a pigtail, which leads into the fir tree and the blade airfoil.

While the metal is being poured into the mold, a heater surrounding the mold keeps the metal in a molten state. The pour is pulled away from the mold and a heat sink contacting the chill block replaces it. As the heat sink pulls heat from the chill block, the heating element surrounding the mold is slowly pulled away, so that cooling (and grain growth) is tightly controlled. Grains begin to form as the metal solidifies, but the cooling pattern forces the grains to grow along the mold, i.e., radially outward. When the cooling metal hits the pigtail, only a few grains can get through the spiral. The few that survive now are free to grow radially along the blade, resulting a in only a few, very long, grain boundaries, and a grain pattern that aligns with the blade span. With fewer (albeit longer) grains and these few grains aligned along the blade's major stress axis (flexural), the blade is significantly stronger than an equiaxed blade.

Single Crystal (SC) blades take the DS methodology further, by eliminating all but one grain from getting through the pigtail. With no inter granular boundaries, there is no method for corrosion or oxidation attack, and no load deformation that might occur between grains.

The production yield for an equiaxed casting might be as high as 95% (depending on the internal and external geometry). The yield rate goes down significantly for DS (40-65%) and even more for SC (25-40%) which drives the per-piece casting cost. (Casting cost is also significantly driven by complexity - internal cores are still assembled by hand at the foundry and a complex modern-day high pressure turbine blade might contain 20-50 ceramic cores. There's also the reality from a design perspective that if you need SC, you are probably also using a complex internal cooling pattern, so you are reducing your production yield probability).

So, back to the original OP: after casting, there's machining, coating, inspection, overhead and profit, etc. In case you weren't aware, the industry standard pricing for aftermarket parts is usually in the 10-12x cost range. (I cringe too when I buy parts for my plane, until I reflect on the reality this business model pays my pension). This is why a replacement turbine blade costing 'X' (per the OP) probably isn't SC or DS.

Somewhere in the house I have a DS high pressure turbine blade that was etched to show the grains. It's a really cool look. I'll post a picture if I can find it.

Art