DeltaHawk for RV-14

[Toobuilder]

I recognize that this thread is specific to the DH and RV-14 installation but since there have been some sweeping assumptions cast about in this thread I think it’s appropriate to address some of them. While it may be true that the 390 and its AV configuration seems to ”require” 100ll from a certification standpoint, I question the applicability to our E-AB world. I have shown that with EFI and proper ignition management, regular old corner gas station junk fuel works fine in my PV 540. Though I have no first hand experience running car gas through an AV engine, I suspect that the superior combustion chamber and cooling design of the AV configuration will actually help the consumption of poor grade fuel. EFI and a “proper” ignition curve is like a magic spell cast over these old engines…. It transforms them into the modern era. Is EFI a more complex installation than mechanical FI and mags? A little. Electrical design is a consideration but the fuel system is not much different than other full return systems used on other airplanes for decades. Is EFI more expensive? Not if you compare retail costs between a Bendix style and EFI - it’s about a wash. So from a retrofit perspective, a builder is far ahead from an immediate financial and build complexity perspective going with Lycoming and EFI than this DH conversion. Is 100ll going away? No doubt. But how about regular old gasoline? Unless you are hunting elk in the Yukon or flying missionaries in Africa, it’s going to be a while before Jet A becomes the defacto liquid fuel IMHO.

Yes, it is now a reality that we “future proof” our builds (that’s exactly why I went with SDS for my Rocket), but I think we need to temper the decisions we make with reality rather than hyperbole. The DH may be an acceptable power plant at some point in the future, but let’s not plan for the unrealistic post- apocalyptic “Mad Max” scenario as justification for a heavy and expensive lump on the firewall today. As was pointed out, the extra up front money for the DH acquisition is likely to serve you far better parked in a simple high yield money market account. I think this build is great and wish DH all the success in the world, but drawing performance and financial based conclusions with virtually zero data is a fools errand. JMHO.

 

[Yank]

I recognize that this thread is specific to the DH and RV-14 installation but since there have been some sweeping assumptions cast about in this thread I think it’s appropriate to address some of them. While it may be true that the 390 and its AV configuration seems to ”require” 100ll from a certification standpoint, I question the applicability to our E-AB world. I have shown that with EFI and proper ignition management, regular old corner gas station junk fuel works fine in my PV 540. Though I have no first hand experience running car gas through an AV engine, I suspect that the superior combustion chamber and cooling design of the AV configuration will actually help the consumption of poor grade fuel. EFI and a “proper” ignition curve is like a magic spell cast over these old engines…. It transforms them into the modern era. Is EFI a more complex installation than mechanical FI and mags? A little. Electrical design is a consideration but the fuel system is not much different than other full return systems used on other airplanes for decades. Is EFI more expensive? Not if you compare retail costs between a Bendix style and EFI - it’s about a wash. So from a retrofit perspective, a builder is far ahead from an immediate financial and build complexity perspective going with Lycoming and EFI than this DH conversion. Is 100ll going away? No doubt. But how about regular old gasoline? Unless you are hunting elk in the Yukon or flying missionaries in Africa, it’s going to be a while before Jet A becomes the defacto liquid fuel IMHO.

Yes, it is now a reality that we “future proof” our builds (that’s exactly why I went with SDS for my Rocket), but I think we need to temper the decisions we make with reality rather than hyperbole. The DH may be an acceptable power plant at some point in the future, but let’s not plan for the unrealistic post- apocalyptic “Mad Max” scenario as justification for a heavy and expensive lump on the firewall today. As was pointed out, the extra up front money for the DH acquisition is likely to serve you far better parked in a simple high yield money market account. I think this build is great and wish DH all the success in the world, but drawing performance and financial based conclusions with virtually zero data is a fools errand. JMHO.

Great points!I believe your comments are relevant to this thread on the DH and RV-14. From a retrofit perspective, I agree that the EFII system would be much less painful for the builde . I'm not in the retrofit position, I'm still doing my tanks and my fuselage kit is on the floor.

I'm pretty sure Lycoming requires 100LL for the IO-390. The EFII system is advertised as being compatible with MOGAS but I do not believe Lycoming supports this. MOGAS is is less expensive, can be used in the E-AB market but is not well supported at FBO's. The University of North Dakota flight school has terminated its year-long test of UL94 and gone back to 100LL. I will be very interested in why they did this. Total install cost of a new IO-390 (plus the EFII system) has been increasing over time to the point that the delta between the two options is starting to narrow but the cost of a DH install is still a BIG question.

DeltHawk suports and is certified for Jet-A. This fuel is currently about the same cost as 100LL but is not going away and is supported at most FBO's. The DH will not be FAA certified for normal diesel fuel but the company does not oppose it in the E-AB market. I believe the difference between Jet-A and diesel fuel on a liquid cooled compression engines is less than the difference between 100LL and unleaded MOGAS on the IO-390. There is no modification to the company supported and FAA certified engine to run diesel fuel in the DH. The IO-390 requires modifying engine with a non certified EFII system not supported by the engine manufacture.

Plenty of questions out there need to be answered. How much with this DH cost? How much will it weigh? What type of prop will it be certified to use? When will it be available and will it be supported by VANs? Why did UND stop using unleaded UL-94 and go back to 100LL.....plenty more questions out there I'm sure....

 

[cjs]

Reading the progress with DeltaHawk I believe they are doing engine/prop combo testing, using instrumented props, to verify compatibility.

Carl

I excited to provide an update on the firewall forward package that DH is working on for the RV14. The main components are as follows:

Engine Mount
DeltaHawk Engine
Starter
Alternator
Cooling Systems: Engine, Fuel, Oil, Inter-cooler (radiators, hoses, tubes, etc)
Ducting for the above items
Wiring Harness and sensors
Oil Tank
Air filter
Exhaust
Heater Core
Cowling
Prop (note: well be using a 2-bladed composite Hartzell prop on my plane for the initial installation - but, DH is working with both Hartzell and Whirlwind for additional options).
Prop Governor
Spinner

Essentially, the FF package is to include everything required for a functioning engine/prop combination.

The target price of the entire package is $110K.

Also, its worth mentioning that the cowling is going look similar to the stock cowling on the 14. We've all seen some interesting looking cowlings paired with new engine alternatives - some better looking than others. The stock RV14 is a good looking plane and or goal is to preserve this aesthetic.

Finally, see attached a couple photos from the DH facility in Racine. We recently shipped the fuselage to Deltahawk's facility for the fitment of the DH200 and newly fabricated engine mount to our airframe. Over the next month or so, the firewall forward installation will be completed to the point run-up tests can be completed. Then the fuselage and engine combo will be shipped back to Synergy Air in Eugene for the final assembly of the plane and subsequent test flights.

Hopefully, the work over the next month or so will provide more opportunities to share the progress.

 

[Carl Froehlich]

I excited to provide an update on the firewall forward package that DH is working on for the RV14. The main components are as follows:

Engine Mount
DeltaHawk Engine
Starter
Alternator
Cooling Systems: Engine, Fuel, Oil, Inter-cooler (radiators, hoses, tubes, etc)
Ducting for the above items
Wiring Harness and sensors
Oil Tank
Air filter
Exhaust
Heater Core
Cowling
Prop (note: well be using a 2-bladed composite Hartzell prop on my plane for the initial installation - but, DH is working with both Hartzell and Whirlwind for additional options).
Prop Governor
Spinner

Essentially, the FF package is to include everything required for a functioning engine/prop combination.

The target price of the entire package is $110K.

Also, its worth mentioning that the cowling is going look similar to the stock cowling on the 14. We've all seen some interesting looking cowlings paired with new engine alternatives - some better looking than others. The stock RV14 is a good looking plane and or goal is to preserve this aesthetic.

Finally, see attached a couple photos from the DH facility in Racine. We recently shipped the fuselage to Deltahawk's facility for the fitment of the DH200 and newly fabricated engine mount to our airframe. Over the next month or so, the firewall forward installation will be completed to the point run-up tests can be completed. Then the fuselage and engine combo will be shipped back to Synergy Air in Eugene for the final assembly of the plane and subsequent test flights.

Hopefully, the work over the next month or so will provide more opportunities to share the progress.

Does the engine mount put the prop in about the same location (fore and aft) as is in a standard Lycoming install?
Carl

 

[czechsix]

I excited to provide an update on the firewall forward package that DH is working on for the RV14. The main components are as follows:

Engine Mount
DeltaHawk Engine
Starter
Alternator
Cooling Systems: Engine, Fuel, Oil, Inter-cooler (radiators, hoses, tubes, etc)
Ducting for the above items
Wiring Harness and sensors
Oil Tank
Air filter
Exhaust
Heater Core
Cowling
Prop (note: well be using a 2-bladed composite Hartzell prop on my plane for the initial installation - but, DH is working with both Hartzell and Whirlwind for additional options).
Prop Governor
Spinner

Essentially, the FF package is to include everything required for a functioning engine/prop combination.

The target price of the entire package is $110K.

Also, its worth mentioning that the cowling is going look similar to the stock cowling on the 14. We've all seen some interesting looking cowlings paired with new engine alternatives - some better looking than others. The stock RV14 is a good looking plane and or goal is to preserve this aesthetic.

Finally, see attached a couple photos from the DH facility in Racine. We recently shipped the fuselage to Deltahawk's facility for the fitment of the DH200 and newly fabricated engine mount to our airframe. Over the next month or so, the firewall forward installation will be completed to the point run-up tests can be completed. Then the fuselage and engine combo will be shipped back to Synergy Air in Eugene for the final assembly of the plane and subsequent test flights.

Hopefully, the work over the next month or so will provide more opportunities to share the progress.

Thanks for the update. Hoping DeltaHawk is planning the locations of the radiators, hoses, exhaust, etc to work with a -14A engine mount as well (to avoid interference with the nosegear assembly)...and not running the exhaust through the tunnel.

The engine mount locations DeltaHawk chose are a strange geometry, I'm sure they had a good reason but it looks a bit unwieldly...it neither conforms to the popular dynafocal type mounting that Lycomings use, nor to the bed mount that some of the big Continentals use. For a purpose-built aircraft engine I would have thought they'd use something closer to one of the existing mounting geometries for easier retrofit. The required mount just doesn't look structurally efficient. Anybody know if the DeltaHawk engine, and the -14 installation specifically, is approved for aerobatics?

 

[cjs]

Does the engine mount put the prop in about the same location (fore and aft) as is in a standard Lycoming install?
Carl

Carl,

It’s looking like the DeltaHawk (prop) will be about 3” forward of the standard Lycoming installation.

However, for a visual comparison - here is my current 14. Its prop is about 2.5” forward due to the light-weight Whirlwind composite prop (pushed prop forward, plus other tweaks, to compensate for CG issues).

So from an aesthetic standpoint the DeltaHawk should be very similar.

Craig

 

[gasman]

That's a lot of weight to push that far from the firewall..... must be be needed. for turbo etc.
I agree, the mount looks like it is not up to the task.

 

[Yank]

Carl,

It’s looking like the DeltaHawk (prop) will be about 3” forward of the standard Lycoming installation.

However, for a visual comparison - here is my current 14. Its prop is about 2.5” forward due to the light-weight Whirlwind composite prop (pushed prop forward, plus other tweaks, to compensate for CG issues).

So from an aesthetic standpoint the DeltaHawk should be very similar.

Craig

Thanks for the update! Keep up the great work…..Many of us out here building are pulling for you.

 

[coloflyer]

Can anyone point to a good recording of a Deltahawk engine running? I'm very curious how it sounds.

Hoping for it to sound as cool as a Detroit Diesel.

 

[Jetmart]

Google is your friend.

 

[coloflyer]

Google is your friend.

Indeed. The youtube search box offered me their channel and not much else.

 

[cjs]

Minor update.

We're definitely in that phase where it seems outwardly that not much progress is being made - but, it is. You know...lots of meetings, texts, zoom calls, office bingo, where to go to lunch today, and the NCAA pool is fast approaching... Oh, and the occasional turn of the ol' wrench. With that said, here's a pic of the plane up on the wheels. Soon the engine, along with all the bits and pieces, will migrate into the picture (so to speak). I will post as more progress is made.

And, worth noting, DH has listened to some of the recent comments suggesting the architecture of the mount may be insufficient to the task. If you look closely, additional duct tape has been added to the critical stress areas!

 

[cjs]

Minor update.

We're definitely in that phase where it seems outwardly that not much progress is being made - but, it is. You know...lots of meetings, texts, zoom calls, office bingo, where to go to lunch today, and the NCAA pool is fast approaching... Oh, and the occasional turn of the ol' wrench. With that said, here's a pic of the plane up on the wheels. Soon the engine, along with all the bits and pieces, will migrate into the picture (so to speak). I will post as more progress is made.

And, worth noting, DH has listened to some of the recent comments suggesting the architecture of the mount may be insufficient to the task. If you look closely, additional duct tape has been added to the critical stress areas!

wrong picture/link - heres the correct one!

 

[coloflyer]

Meanwhile - a good article with lots of relevant information is this article from the Cessna Pilots Magazine - it covers a lot of ground.

https://www.deltahawk.com/wp-content/uploads/2023/12/CessnaPilotsMagazine-DeltaHawk-Nov2023.pdf

This article was fantastic and got me over the hump of placing a deposit! Thank you. I understand how this would've taken so long and just how different the DH is than those built on an auto diesel core. Heck even the metallurgy probably took a hot minute.

I have a sense government integrators will be very interested in DH for UAS applications.

 

[cjs]

Not so much related to our RV14/DeltaHawk build progress, but there is some news related to the performance of the DH180 in their Cirrus test plane.

From Delta Hawk:

DeltaHawk just completed a historic flight in an otherwise stock Cirrus SR20 powered by a DeltaHawk DHK180 engine. The flight was non-stop from Racine, WI (KRAC) to Jacksonville, FL (KVQQ), a total of 818 Nm (940 SM), at an average 148 Kts (170 mph) True Airspeed and a total fuel burn of 45 gallons of Jet A.

The aircraft landed with over one hour of fuel reserve, whereas a stock aircraft would have required an enroute fuel stop. The stock SR20 flying the same mission would have required 35-38% more fuel, plus the extended time required for the fuel stop.

Thought I'd share this as it speaks to one of the primary reasons I am excited about the installation in the RV14 (no, its not that I am excited to fly 5.5 hours without a bathroom break!). While there are a whole host of differences between the RV14 installation and the Cirrus's, the range and fuel savings benefits should be similar. And, just a reminder - we are using the DH200, not the180.

Somewhat related, and likely of interest to many - the DH engine is capable of burning regular diesel gas (not just JetA). That said, there are OAT issues to consider - JetA has anti-freezing additives, where as diesel generally does not a have these (there are exceptions, for winter blends). Basically, JetA is formulated to deal with sub-zero temps (which are not all that unusual to encounter at higher altitudes). That said, for many folks it (low OATs) may not be an issue in many of their flights - so, using diesel could be another significant source of savings/efficiency. I will get more info on this subject later - including the pratical aspects of whether one can mix JetA and Diesel (this would make fueling easier as one would not have to drain the one type to use the other).

 

[Carl Froehlich]

Somewhat related, and likely of interest to many - the DH engine is capable of burning regular diesel gas (not just JetA). That said, there are OAT issues to consider - JetA has anti-freezing additives, where as diesel generally does not a have these (there are exceptions, for winter blends). Basically, JetA is formulated to deal with sub-zero temps (which are not all that unusual to encounter at higher altitudes). That said, for many folks it (low OATs) may not be an issue in many of their flights - so, using diesel could be another significant source of savings/efficiency. I will get more info on this subject later - including the pratical aspects of whether one can mix JetA and Diesel (this would make fueling easier as one would not have to drain the one type to use the other).

Diesel fuel has ~2.7% more BTUs/gallon than Jet A, so a small advantage by volume. Diesel fuel however is ~5% heavier per gallon than Jet A. As example, for an RV-10 a full tank of diesel will weight ~20 pounds more than a full tank of Jet A.

The freezing issue, for us, can be managed by procedure. I’m hopeful we’ll verify no issues with mixing diesel with Jet A.

Carl

 

[Toobuilder]

Diesel fuel…

…is also the same price or more expensive than 100ll in this part of the country. What used to be a “junk” fuel is now the highest price option California drivers can pick from. The reasons for that are outside the bounds of this forum, but they are nevertheless an economic reality for many.

 

[cjs]

…is also the same price or more expensive than 100ll in this part of the country. What used to be a “junk” fuel is now the highest price option California drivers can pick from. The reasons for that are outside the bounds of this forum, but they are nevertheless an economic reality for many.

I just did a quick look at 100LL vs JetA between southern Oregon all the way up to Seattle, using Foreflight - here's what I found:

100LL: Lowest - $5.63 Highest - $7.25
JetA: Lowest - $4.93 Highest - $7.50

Then, using GasBuddy - here's what I am currently seeing for Eugene, OR (I'm not sure how to search a wider area on this app):
Diesel: Lowest - $3.69 Highest - $4.09

So, possibly for some folks using diesel will translate to some noticeable savings.

 

[Dugaru]

As soon as one starts to climb the diesel Sportsman leaves the Lycoming in the dust, or rather, in its soot trail.

 

[rocketman1988]

I will be interested to see how the organic issue plays out in a hobby aircraft. Organic material can grow in Jet A if left undisturbed…

 

[Flandy10]

I will be interested to see how the organic issue plays out in a hobby aircraft. Organic material can grow in Jet A if left undisturbed…

In 7.5yrs, I never saw any microbial growth in the JetA. A little Biobor JF treatment every few months and an annual HUM-bug test kept the critters away.

 

[rocketman1988]

In 7.5yrs, I never saw any microbial growth in the JetA. A little Biobor JF treatment every few months and an annual HUM-bug test kept the critters away.

That’s why I said I was curious. We had a jet a tank truck at our airport and it didn’t get used very much…it did grow things, though.

 

[Yank]

they are nevertheless an economic reality for many.

What I would also consider an economic reality if I lived in California would be the cost difference and availability of 100UL vs Jet-A. Especially when the state outlaws 100LL.

 

[cjs]

I just did a quick look at 100LL vs JetA between southern Oregon all the way up to Seattle, using Foreflight - here's what I found:

100LL: Lowest - $5.63 Highest - $7.25
JetA: Lowest - $4.93 Highest - $7.50

Then, using GasBuddy - here's what I am currently seeing for Eugene, OR (I'm not sure how to search a wider area on this app):
Diesel: Lowest - $3.69 Highest - $4.09

So, possibly for some folks using diesel will translate to some noticeable savings.

Follow up to my previous post regarding the use of diesel and whether it can be mixed w JetA.

From a practical standpoint, being able to mix JetA and diesel would be ideal in the real world of our experimental GA flying - it would provide more options when refueling, especially on long trips. From my personal perspective - I largely depart from my ranch where I have diesel. It would be hard to pass up using diesel when its about $1-2 less expensive than JetA. But, I’m aware that if a trip is long enough, I may need to refuel and JetA may be my only convenient option. If I can’t mix the fuels, then I’d have to opt for only JetA on long cross-country trips.

So far, we’ve not been able to find any studies on whether it’s practical to mix the two fuels. And, if so, when and to what effect. Regardless, we suspect, mixing is not a viable option in the winter as the additives in diesel may precipitate (generally at temps below freezing) and could clog the fuel delivery system.

We are continuing to research this issue and I’ll update if we find anything pertinent. Certainly, if someone in this forum is knowledgeable on this topic, we’d welcome the input.

Lastly, In spite of the uncertainty of the mixing of JetA and diesel, straight diesel still seems to be a viable option in the warmer months of the year. It appears the worst case will be that come winter (or any flights in sub-zero temps), one would have to drain the tanks of diesel and switch to straight JetA.

And, as for cross-country trips on diesel - the issue of mixing fuels may be only an issue on very long trips (especially when factoring the higher efficiency/range of the DH engine).

 

[TYK]

Winter blend diesel fuel for our farm machinery and trucks is simply #1 diesel added to the tank of #2 diesel. Of course we want testing for safety but I would be surprised to find any blending issues between #2 diesel and jetA. The thing about using diesel is to avoid bio blended fuel, it can jell at much warmer temperatures. Algae growth is a real thing and quite a pain but additives can prevent that.

 

[TYK]

On another issue, when I learned to drive truck it was an old 2stroke Detroit Diesel. They had no torque below about 2000 rpm, ran best “rapped out”. Standard training for driving one was to slam your hand in the door until you are mad enough to drive it. I don’t know if we’ll be able to run a delta hawk in an RV without doors…..

 

[coloflyer]

Follow up to my previous post regarding the use of diesel and whether it can be mixed w JetA.

From a practical standpoint, being able to mix JetA and diesel would be ideal in the real world of our experimental GA flying - it would provide more options when refueling, especially on long trips. From my personal perspective - I largely depart from my ranch where I have diesel. It would be hard to pass up using diesel when its about $1-2 less expensive than JetA. But, I’m aware that if a trip is long enough, I may need to refuel and JetA may be my only convenient option. If I can’t mix the fuels, then I’d have to opt for only JetA on long cross-country trips.

So far, we’ve not been able to find any studies on whether it’s practical to mix the two fuels. And, if so, when and to what effect. Regardless, we suspect, mixing is not a viable option in the winter as the additives in diesel may precipitate (generally at temps below freezing) and could clog the fuel delivery system.

We are continuing to research this issue and I’ll update if we find anything pertinent. Certainly, if someone in this forum is knowledgeable on this topic, we’d welcome the input.

Lastly, In spite of the uncertainty of the mixing of JetA and diesel, straight diesel still seems to be a viable option in the warmer months of the year. It appears the worst case will be that come winter (or any flights in sub-zero temps), one would have to drain the tanks of diesel and switch to straight JetA.

And, as for cross-country trips on diesel - the issue of mixing fuels may be only an issue on very long trips (especially when factoring the higher efficiency/range of the DH engine).

Oh the raised eyebrows I'll get for running Ag use tinted diesel from our farm co-op... it is for 'off-road use' only so I think I'm good lol.

 

[cjs]

FYI - Just listed my Lycoming IO-390 EXP for sale in the classified section. This was the one I was going to use until we became the test bed for the new DeltaHawk engine.

FS: New Thunderbolt IO-390 exp & FF Kit, available immediately

Available for immediate Pick-Up form SynergyAir in Eugene, OR: Brand new. Planned to use these in my latest RV14 build. As you may have seen, I am now the test bed for the DeltaHawk engine, so I wont be needing the Lycoming. Engine and FF kit were purchased thru Van's Received it on 6/9/21...

vansairforce.net

 

[MCA]

Glad I didn't wait for the DeltaHawk firewall forward kit promised at Oshkosh when I was building my RV6. First flight was 17 years ago, and they've never sent me an update on when it will be available.....

don't hold your breath....

Different owners, different financing...

 

[cjs]

Another short update.
Good progress is being made on the engine installation and FF package. No pics to share of that just yet, but will have some soon.
Good work has been done on the design and layout of the heat exchangers and they are being fabricated as I write this. The cowling is mostly designed, but fabrication is still a bit out. Once the cowling design is finalized, I will get the CADs out for all to see. It will largely mimic the aesthetic of the stock 14.
All that aside, here are the CAD drawings of the exhaust scheme we will use. As you can see, we will be using the tunnel.

And, finally, another short plug - I have a brand new IO-390 EXP and FF kit for sale. Clearly, I am all in on this DH project - so, I don't need the Lycoming (that was originally spec'd for this plane). Its ready for immediate shipment or pick-up at the Synergy Air location in Eugene, OR.

 

[MCA]

You gotta love that turbo!

 

[Phil Sprang]

I'm really enjoying this thread. Love the innovation and I hope it all comes together.
The Turbocharging is interesting and I hope I'm not opening a can of worms but how is that going to work with the Vans published Vne of 200 knots indicated AND true airspeed? It seems to me that it would be trivial to bust 200 knots true at altitude.

 

[cjs]

I'm really enjoying this thread. Love the innovation and I hope it all comes together.
The Turbocharging is interesting and I hope I'm not opening a can of worms but how is that going to work with the Vans published Vne of 200 knots indicated AND true airspeed? It seems to me that it would be trivial to bust 200 knots true at altitude.

It’s a bit early to speak to the performance numbers we’re expecting with the DH200 on the RV14. But, the planes ability to exceed the 14’s Vne is clearly possible, especially if one is cruising in the teens or above.

We are purposely being circumspect about putting numbers out there until we have actual performance data. That said, we do expect to see impressive sustainable climb performance - even when dealing with density altitude issues. And, there is little doubt the cruise numbers should be equally impressive as well. We plan to share actual flight test data (videos, too) when we get to that stage of development.

On Vne specifically - and this is just my personal take - I am fine if the plane is capable of exceeding Vne. Doesn’t mean I will do so, though (and, fortunately, the Garmin G3x has programmable audio and visual alerts for Vne) What I am more excited about is the sustainable climb performance in adverse temps or altitudes. If the additional power due to the forced induction system then allows me to throttle back at altitude (to avoid Vne) and gain even more cruise/fuel effifiency - then I consider that a win as well.

Here’s an interesting article Paul Dye at Kitplanes published in January. It’s about the turbo-charged Rotax in an RV9. That engine, if I recall correctly, is rated for 137hp continuous and the cruise numbers are pretty impressive at 12k msl.

On the Nose! - KITPLANES

Lockwood’s Rotax-powered RV-9A is more than just fancy rhinoplasty.

www.kitplanes.com

Craig

 

[czechsix]

All that aside, here are the CAD drawings of the exhaust scheme we will use. As you can see, we will be using the tunnel.

Craig, thanks for the pics and regular updates. Hoping this engine and installation are successful so we can finally have a better alternative to the IO-360/390. That's a big exhaust pipe diameter! I wonder if they'll be able to use the tunnel for the exhaust on an RV-14A installation...might be possible with a different routing to squeeze it by the nose gear shock mount assembly & supporting steel tube structure. If not, it would require some other exit location in the lower cowl. Hopefully DH is thinking through the -14 vs. -14A geometry to minimize the number of differences beyond the engine mount/gear leg structure. Do you know if they have CAD drawings for the -A model as well?

 

[Jjackh10]

Winter blend diesel fuel for our farm machinery and trucks is simply #1 diesel added to the tank of #2 diesel. Of course we want testing for safety but I would be surprised to find any blending issues between #2 diesel and jetA. The thing about using diesel is to avoid bio blended fuel, it can jell at much warmer temperatures. Algae growth is a real thing and quite a pain but additives can prevent that.

My modern Duramax, has demonstrated safe operation on various combinations of; Jet A, mineral oil, ATF, and "off road" diesel. (BTW red diesel is just dyed, no such thing as "High Sulphur" diesel anymore).
I'd wager that this engine would actually prefer a blend. Jet A is very dry, and a little hard on the fuel pumps and injectors. So blending in a little diesel or a splash of ATF would likely extend the life of those components a bit.

 

[BillL]

Interesting information gathering here. This power plant will have more credibility with a teardown of a 1000hr test (mission cycle profiles) and publishing of the inspection report. Nothing like that expected soon. I hope the company fully supports the RV builds to learn and defray some of the personal costs. Then, provide support and fuel for lots of flight hours. Lots and lots. 2, 3, and 4 hour flight missions, then stop at local airports and show it off. No better way to learn if your product design is properly matched to reality than good field testing. The rolling stock industry has been heading to that for 50 yrs, yet there is always something new in the materials, processing and assembly that must be discovered in the field. The final operating cost per hour to TBO must be shown with some balance on the higher up front portion.

 

[BillL]

My modern Duramax, has demonstrated safe operation on various combinations of; Jet A, mineral oil, ATF, and "off road" diesel. (BTW red diesel is just dyed, no such thing as "High Sulphur" diesel anymore).
I'd wager that this engine would actually prefer a blend. Jet A is very dry, and a little hard on the fuel pumps and injectors. So blending in a little diesel or a splash of ATF would likely extend the life of those components a bit.

The Duramax, being an Isuzu design/developed product, had to qualify for japanese kerosene. Historically Japanese K1 was the worst for seizing and galling of all the world's fuels. Like water, it is. It appears to have scroll pumps on the DH. This design will not allow some of the fuel injection controls of 3 decades of injection system knowledge. Pilot injection is one that would allow a soft pressure ramp rate in combustion at idle, his is what has eliminated the idle clatter, since introduction with the PowerStroke HEUI. It removes the sledge hammer explosion at idle where all the fuel needed is injected within the combustion ignition delay period.

 

[Jjackh10]

The Duramax, being an Isuzu design/developed product, had to qualify for japanese kerosene. Historically Japanese K1 was the worst for seizing and galling of all the world's fuels. Like water, it is. It appears to have scroll pumps on the DH. This design will not allow some of the fuel injection controls of 3 decades of injection system knowledge. Pilot injection is one that would allow a soft pressure ramp rate in combustion at idle, his is what has eliminated the idle clatter, since introduction with the PowerStroke HEUI. It removes the sledge hammer explosion at idle where all the fuel needed is injected within the combustion ignition delay period.

Cool, learned something new today! So theoretically at idle, the DH will sound like an old cat road grader? haha.

 

[cjs]

Craig, thanks for the pics and regular updates. Hoping this engine and installation are successful so we can finally have a better alternative to the IO-360/390. That's a big exhaust pipe diameter! I wonder if they'll be able to use the tunnel for the exhaust on an RV-14A installation...might be possible with a different routing to squeeze it by the nose gear shock mount assembly & supporting steel tube structure. If not, it would require some other exit location in the lower cowl. Hopefully DH is thinking through the -14 vs. -14A geometry to minimize the number of differences beyond the engine mount/gear leg structure. Do you know if they have CAD drawings for the -A model as well?

Mark,
DH is planning on a package for the RV14A as well. The exhaust routing will be different, and likely not use the tunnel. The rest of the package will be very similar to the 14. That said, we will focus on the Tail Dragger package first and make sure its dialed in before doing much work on the 14A. No CADs available on this yet (the 14A), but when its in development, I am sure they will share. I should have some more updates at the end of this week.
Craig

 

[Canadian_JOY]

I keep dreaming that I'll hear D-H is working on a FWF package for the Glasair Sportsman. That would be the cat's meow for me!

 

[BillL]

A little closer looking at the FWF CAD shows a belt driven blower - -and thinking back to the Contintental 2-stroke,the DH shows a lot of the same basics with vee configuration to allow a stiffer case. A look at the pistons could be revealing. On the turbo. . . A/F for the diesel is still important and as it gets lower (24:1) the temps of everything go higher. Also, one can overstress a diesel easily with more fuel, just twist of a screw (typically). Cylinder pressures are important to manage as the 20:1 Cr really pushes up the average peak pressures. This engine will require different thinking for the pilot. Just because it is flat rated does not mean it should be used. A non firing 10:1 Cr on a gasoline engine at idle ( low manifold pressure) can only be 40 PSI (as I measured it). A diesel will have full compression pressure every stroke. Diesels are quite a different combustion engine.

 

[Yank]

Another short update.
Good progress is being made on the engine installation and FF package. No pics to share of that just yet, but will have some soon.
Good work has been done on the design and layout of the heat exchangers and they are being fabricated as I write this. The cowling is mostly designed, but fabrication is still a bit out. Once the cowling design is finalized, I will get the CADs out for all to see. It will largely mimic the aesthetic of the stock 14.
All that aside, here are the CAD drawings of the exhaust scheme we will use. As you can see, we will be using the tunnel.

And, finally, another short plug - I have a brand new IO-390 EXP and FF kit for sale. Clearly, I am all in on this DH project - so, I don't need the Lycoming (that was originally spec'd for this plane). Its ready for immediate shipment or pick-up at the Synergy Air location in Eugene, OR.

Thanks for the update! One question, is it an oil/air or fuel/air heat exchanger you are working on.

 

[cjs]

Thanks for the update! One question, is it an oil/air or fuel/air heat exchanger you are working on.

Yank,
I spoke with the engineers at DeltaHawk so I could get a few more details before responding. Here's the gist of the discussion:

The Cirrus installation was developed using off-the-shelf heat exchangers. The Cirrus's Radiator and intercooler were automotive spec - relatively heavy, and optimized for lower airspeeds.

For the RV14, DeltaHawk is working with a company, Aero-Classics, (DH says they are "pretty much the Michael Jordan of heat exchanger design and manufacturing") to develop a complete heat exchanger package (radiator, intercooler, and oil cooler) tailored specifically for our application. The package is lighter and will induce less drag than the Cirrus package.

Radiator is liquid to air.
Intercooler air to air.
Oil cooler is liquid to air.

Hope this answers your question.
Craig

 

[czechsix]

Craig, have you (or DeltaHawk) tried to run the numbers on real-world FWF weight of the DH200 installation vs. IO390, including all fluids? Wondering if you'll need to make other changes such as locating the main battery back by the elevator bellcrank the way it is on the RV-10 (also on RV-8's that use an angle valve engine) to keep CG from being too far forward. I suppose you could complete the airplane and then do the full up W&B but if it turns out to be nose heavy it will be more effort at that point to relocate things. Can always throw a case of oil in the baggage compartment but not an ideal solution for CG adjustment.

 

[MIKE JG]

Dumb question here but if someone was planning on running this engine in the future and they were just starting their fuel tanks, any differences to be aware of to run Jet-A instead of 100LL or 94UL??

 

[Carl Froehlich]

Dumb question here but if someone was planning on running this engine in the future and they were just starting their fuel tanks, any differences to be aware of to run Jet-A instead of 100LL or 94UL??

Yes.

At a minimum you need to add a 3/8” AN fitting for fuel return (one on each tank). This also required a duplex fuel valve so you are retuning fuel to the same tank you are taking it out of.

If you decide to do the DeltaHawk, replace the round fuel fill with the Jet A ”duckbill” during tank construction. You can get an adapter to fit on the Jet A duckbill fuel fill nozzle to fit the standard round fuel fill but odds are the line guy will refuse to fill your tanks up with Jet A as they are trained to never put Jet A into a tank that cannot take the duckbill nozzle.

Carl

 

[cjs]

Craig, have you (or DeltaHawk) tried to run the numbers on real-world FWF weight of the DH200 installation vs. IO390, including all fluids? Wondering if you'll need to make other changes such as locating the main battery back by the elevator bellcrank the way it is on the RV-10 (also on RV-8's that use an angle valve engine) to keep CG from being too far forward. I suppose you could complete the airplane and then do the full up W&B but if it turns out to be nose heavy it will be more effort at that point to relocate things. Can always throw a case of oil in the baggage compartment but not an ideal solution for CG adjustment.

Mark,
Short answer: Yes. Longer version: We're focused on getting the installed weight as close to the IO-390 as possible, and ensuring the CG is not adversely affected. This was and is a primary goal of the engine package, and DeltaHawk is making good progress. As an example, the cooling system components (turbocharger, oil, and engine) have been custom designed just for the 14 installation - the hoses, fittings and heat-exchangers. That alone appears to have shaved about 10# from the overall package weight. There's lots more, but until we have the engine set-up finalized, I can't go into many specifics. Bottom line - our goal is to deliver a well refined package that is very close weight-wise to the Firewall Forward IO-390 installed weight. I am very optimistic this goal will be achieved. Will let you know more as I am able.
Craig

 

[georgemohr]

This is a really exciting development. Wish you luck.

 

[cjs]

All,
Here are some more CADs on the engine installation. These show more detail on what will be the final locations of the heat exchangers and sundry other things.
The engine and component layout phase is taking longer than we expected - but, this is largely because our goal is a complete package ready to present to other RV builders, not just a Frankenstein-ed test bed that isn't ready for mass uptake. If we are successful in this (and, I believe we will be) - there will be very little development work left to do between the package (engine prop, firewall forward stuff) we're putting on my RV14 and what will be later offered to the general RV14 community of builders.

Here are some of the components we are working on and a few thoughts on each:

Cowling: DH is working with a cowling manufacturer on a carbon fiber model. The shape will be very similar to the stock cowl, but distinct enough to telegraph there is something different under the hood. There will be some weight savings as well.

Prop: DH is speaking with a number of prop manufacturers. We have a few choices right now on props that will work, but are looking to narrow this down to one or two 'preferred' props. There is potential to save weight in this area as well (both in the prop and the spinner components).

Panel: We have been working directly with Aerotronics on the panel. Jason Smith (Aertronics) has been exceptionally helpful. Synergy and I have worked with him in the past and his technical knowledge combined with his understanding of pilot needs (he flys, too) is invaluable. The DH engine being different in many ways from the lycoming (no mags, no plugs, turbocharged, etc., etc.) has a lot of downstream impacts on the architecture and functionality of the panel. Jason has helped us sort this all out. We only just finalized the design and I will soon publish the layout for all to see. Its a full IFR Garmin set-up. I've been flying extensively (about 1000 hours) behind a similarly designed and equipped panel (albiet, for a Lycoming), and from a pilots/flying perspective its great.

With all this said - I have to say we will not be flying before OSH 2024. Bummer. It does, however, look like we will have the engine package installed to the fuselage and on display at Air Venture 2024 for everyone to see. We should have static test runs completed by then as well.

Once Air Venture 2024 has ended, the engine/fuse will be shipped to SynergyAir in Eugene for final assembly and test flights. Realisticly, this means the first flight data will probably not be out until October. We will, nonetheless, keep posting on the progress as we move forward.

One last note - Delta Hawk and Piper Aircraft Company just reached an agreement to "begin development of a Supplemental Type Certificate (STC) for installation of DeltaHawk’s engine in Piper’s legendary PA-44 Seminole twin in both new and retrofit aircraft". I know there are folks who question DH's commitment and/or capabilities to fullfill the promises of this engine's development. Its certainly been a long time in process. But, there are many signs to indicate they are indeed committed and it appears many end users are excited about the capabilities of the engine. I can attest that they are fully engaged on working with the experimental community.

And, one last addendum: Here's a YouTube link to an Aviation Consumer piece on DeltaHawk at Sun'N' Fun. If you look fast at the 5:30 mark you'll see our RV14 project.

 

[benjaman]

Craig,

Thanks for the updates on this and please keep them coming, great work you’re all doing there.

I’m new to homebuilding having just started my RV-10 tailcone, but not to product development. It’s one thing to develop great technology but another to be commercially successful with it. You can have the best solution for any given challenge, but if market conditions are against you it can be almost impossible to build a business around it. Until those conditions change or you find a better application. If engine manufacturers are able to utilize decades-old machinery to make proven engines at low cost but can sell them for high prices, that’s hard to compete with. Until fuel options change, for example. Disruption is hard, but it’s amazing when it happens. Before it happens, most people think it is impossible. When it does, most people say it was inevitable. It never was and it never is—it takes relentless developers to keep pushing and bridge the gap.

Kudos to you and the team and I wish you best of luck. By the time I get to my FWF kit, I look forward to having another engine option to choose from.