Anyone Flying a Velocity V-Twin?

John Myers said:
How practical/impractical would it be to deice the twin? ThermaWing was mentioned earlier in the thread.

With a pair of diesels and a deiced wing/canard this would be something.
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I could be wrong but I believe getting FIKI certification takes a flight behind a tanker spraying water on the plane. Whether or not you need FIKI certification on the plane to file a flight plan into known icing conditions or can legally fly in said conditions without it is above my current pay grade.
 
Juliet Hotel said:
Getting FIKI certification takes a flight behind a tanker spraying water on the plane. Whether or not you need FIKI certification on the plane to file a flight plan into known icing conditions or can legally fly in said conditions without it is above my current pay grade.
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As far as I know there is no such thing as FIKI certification on an experimental airplane.
 
John Myers said:
As far as I know there is no such thing as FIKI certification on an experimental airplane.
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So can you legally take it into known icing? What do the Boeing folks do with the dreamlifter?
 
John Myers said:
How practical/impractical would it be to deice the twin? ThermaWing was mentioned earlier in the thread.

With a pair of diesels and a deiced wing/canard this would be something.
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There is no E/AB aircraft certified for FIKI. And there probably never will be. There is no way an experimental aircraft manufacture would go to the trouble.
 
donjohnston said:
There is no E/AB aircraft certified for FIKI. And there probably never will be. There is no way an experimental aircraft manufacture would go to the trouble.
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It’s not that they aren’t, it’s that they can’t be. Also they are already legal to fly in icing as far as I know so there would be no reason to.
 
donjohnston said:
I'm going to file this under "There's right and then there's dead right". :D
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You implied an uncertified aircraft could be certified for FIKI if only a manufacturer went to the trouble. That is incorrect.
 
John Myers said:
You implied an uncertified aircraft could be certified for FIKI if only a manufacturer went to the trouble. That is incorrect.
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I didn't imply it. I stated it outright.

If the manufacture doesn't do it, then it would have to be the builder. And I can't see a typical builder going through whatever hoops to obtain that certification. I'm guessing that have to prove that the system works. Which would have to be a wind tunnel or some type of actual flying in icing. Maybe someone else here knows what that process is but I got think it's not easy.
 
donjohnston said:
I didn't imply it. I stated it outright.

If the manufacture doesn't do it, then it would have to be the builder. And I can't see a typical builder going through whatever hoops to obtain that certification. I'm guessing that have to prove that the system works. Which would have to be a wind tunnel or some type of actual flying in icing. Maybe someone else here knows what that process is but I got think it's not easy.
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Based on the tone I'm worried this is going to turn into a Facebook type back and forth, so I'll leave this here for people to start to dig further if wanted: http://eaaforums.org/showthread.php?1260-FIKI-and-Amateur-Build-Aircraft/page2
 
I never said it wasn't permitted.

I think you are confusing "allowed" with "certified".

There is a huge difference between the two.
 
donjohnston said:
I didn't imply it. I stated it outright.

If the manufacture doesn't do it, then it would have to be the builder. And I can't see a typical builder going through whatever hoops to obtain that certification. I'm guessing that have to prove that the system works. Which would have to be a wind tunnel or some type of actual flying in icing. Maybe someone else here knows what that process is but I got think it's not easy.
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I was curious about this once. I asked a FSDO rep at a FAST event for EAA. She walked me through it; but I may not have it exactly correct. So do not kill me if I get it wrong.
FIKI standards and regulations are written expressly to apply to a type certificated design. EAB does not have a type certified design.
As such, EAB can Never be FIKI. To get FIKI, you must certify the plane which automatically removes it from EAB.

Tim
 
tspear said:
Depends more on the ops limitations for the specific plane than anything else.

Tim
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Juliet Hotel said:
I could be wrong but I believe getting FIKI certification takes a flight behind a tanker spraying water on the plane. Whether or not you need FIKI certification on the plane to file a flight plan into known icing conditions or can legally fly in said conditions without it is above my current pay grade.
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John Myers said:
How practical/impractical would it be to deice the twin? ThermaWing was mentioned earlier in the thread.

With a pair of diesels and a deiced wing/canard this would be something.
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ThermaWing was mentioned earlier. Was looking into it as well and noticed that Therm-X is the experimental airplane version of ThermaWing, both made by RDD. Therm-X was also specifically mentioned use for the Velocity. They advertised around $26K installed. Anyone have any experience with this system in how it works? The comments on their site claimed it worked better than TKS.
 
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BrenE said:
ThermaWing was mentioned earlier. Was looking into it as well and noticed that Therm-X is the experimental airplane version of ThermaWing, both made by RDD. Therm-X was also specifically mentioned use for the Velocity. They advertised around $26K installed. Anyone have any experience with this system in how it works? The comments on their site claimed it worked better than TKS.
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I did a demo flight with it back when Cessna briefly sold the TTx with it. From what I recall, it worked really well, was easy to operate, flip a switch and the snow melted.
Cessna eventually pulled the plug on it due to some issues for which Cessna would not talk about it.

Tim
 

Pretty cool video. Twin turbine Velocity will be swanky!
 
donjohnston said:
That's a nice sound. Wonder what the fuel burn will end up at.
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Going on memory from a few years ago when I talked to PBS, expected fuel burn was between 20-22 GPH per engine for 95% power. And you would make 95% up to around 10K.

Tim
 
Public Broadcasting Service


//jk
PBS makes the engines, or at least did at some point. Look up PBS Aerospace
 
I have never heard a turbine start so quickly. It must have internals with pretty low mass to get them to spin up like that.
 
J. Taylor Stanley said:
I have never heard a turbine start so quickly. It must have internals with pretty low mass to get them to spin up like that.
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FYI: these type engines are considered a micro-turbine and operate a bit different than a P&W PT6 or other conventional turbine engine. Being most are not a free-turbine design and all internal wheels are on one or 2 shafts it will spool up very fast similar to the old original fixed turbine engines. There are several OEMs for this type engine as they are making inroads on the E-aircraft industry to replace battery banks with small, lightweight turbine engine/generator packages that will eventually burn 100% SAFs. Think of it as a flying APU that powers electric propulsion motors.
 
Bell206 said:
FYI: these type engines are considered a micro-turbine and operate a bit different than a P&W PT6 or other conventional turbine engine. Being most are not a free-turbine design and all internal wheels are on one or 2 shafts it will spool up very fast similar to the old original fixed turbine engines. There are several OEMs for this type engine as they are making inroads on the E-aircraft industry to replace battery banks with small, lightweight turbine engine/generator packages that will eventually burn 100% SAFs. Think of it as a flying APU that powers electric propulsion motors.
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Are they axial turbines? Most of the smaller ones I have seen on drones and high end RC are centrifugal style. They are cheaper to build, but have a higher fuel burn.
 
J. Taylor Stanley said:
Are they axial turbines? Most of the smaller ones I have seen on drones and high end RC are centrifugal style.
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Depending on the design they use various combinations like either an axial or centrifugal for the compressor (or both) and an axial or radial (centrifugal) for the power turbine. As to the build cost I believe you are thinking of a fixed turbine vs free turbine. Most of these micro turbines, APU turbines, RC turbines, etc. are fixed turbines which are cheaper to build, burn more fuel, and have various disadvantages when compared to a free turbine. But I think in the applications they are using these type turbines (and similar types) they will be at a price point comparable to some recip engines. I've seen some data comparing costs of a Rotax 912 to an equally sized regenerative micro turbine which has some people rather excited enough to invest millions. However, I think the initial market will be on the E-aircraft side before they start to replace a Rotax with a turbine.
 
The word from Velocity is they expect 32-34 GPH. Speed is an unknown but they think at least 250kts at altitude.

It'll hold 165 gallons of fuel.

That's a whole lotta money in fuel. Hard to believe there's a market for a 4-place twin turboprop burning 34GPH. Maybe this is just for testing and they'll use it on the 6-place twin.
 
donjohnston said:
The word from Velocity is they expect 32-34 GPH. Speed is an unknown but they think at least 250kts at altitude.

It'll hold 165 gallons of fuel.

That's a whole lotta money in fuel. Hard to believe there's a market for a 4-place twin turboprop burning 34GPH. Maybe this is just for testing and they'll use it on the 6-place twin.
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Not sure the same owner. When I was talking to the Velocity factory and PBS, I ended up talking to a potential builder of a turbine V-Twin. Not sure if the same gentleman. He was focused on the Jet-A aspect for international travel, and currently flew a lot to South America with stops in the Caribbean.
The BSFC on that type of turbine is supposed to be fairly flat until you get too low. The BSFC is roughly double what you would expect from a descent piston engine; so I would expect that the range would be roughly halved. With the price difference between Jet-A and avgas outside the USA, that could be worth it.

Tim
 
Were I flying internationally I'd want an airplane with an o360 or an 0320 with low compression cylinders. They'll burn car gas all day long, and there's lots of that everywhere you go.
 
But at 150kts with that 320 or 360, it'll take a lot longer to get to those international destinations. :D
 
steingar said:
Were I flying internationally I'd want an airplane with an o360 or an 0320 with low compression cylinders. They'll burn car gas all day long, and there's lots of that everywhere you go.
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Serious question, because earthrounding is on my "maybe" bucket list -- but this stuff isn't at airports -- you would propose to haul a few jugs of mogas to the airport?
 
steingar said:
Were I flying internationally I'd want an airplane with an o360 or an 0320 with low compression cylinders. They'll burn car gas all day long, and there's lots of that everywhere you go.
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FYI: you'd be better served to have an aircraft that burned diesel especially with the V turbines above as most of that size are already using diesel as fuel. There's a lot more diesel available overseas than gasoline especially when outside the large population centers. Even Pratt certified several PT6A models to use diesel in AG work only in various countries due to aviation fuel costs and logistics.
 
I could be wrong but my impression from what I've read and seen was that avgas is scarce, but JetA and diesel are plentiful outside the US, so you're better bet is run something that burns JetA/diesel
 
Bell206 said:
FYI: you'd be better served to have an aircraft that burned diesel especially with the V turbines above as most of that size are already using diesel as fuel. There's a lot more diesel available overseas than gasoline especially when outside the large population centers. Even Pratt certified several PT6A models to use diesel in AG work only in various countries due to aviation fuel costs and logistics.
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Tantalum said:
I could be wrong but my impression from what I've read and seen was that avgas is scarce, but JetA and diesel are plentiful outside the US, so you're better bet is run something that burns JetA/diesel
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I think this all holds true IF you have to burn AVGAS. But as Steingar points out, if you can burn MOGAS you're in pretty good shape. I've been all over (to include some armpit areas like Iraq and Afghanistan) and in my experience MOGAS was always available.
 
tsts4 said:
in my experience MOGAS was always available.
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While my experience in Central/South America is different, you still need to verify the MOGAS side. A number of countries mandate ethanol blends vs using MOGAS. For example, in Brazil your options are E25 and E100. So its important to verify 1st before flying out whether AVGAS or MOGAS is available whereas diesel or JetA is everywhere most people would venture to.
 
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