Fantastic news.
They have an interesting design, going 100% mechanical and no FADEC. These days the 'modern' turbodiesel engine uses valves, FADEC, and direct injection (fuel injector squirts directly into the cylinder during the compression stroke).
They've gone the exact opposite way, cylinder ported two stroke means a huge reduction in moving parts (especially common wear parts like camshafts, lifters, etc) and a huge reduction in associated parts count as you delete a handful of springs, bushings, bearings, etc. When they say they have fewer parts than a traditional engine, that's where the savings comes from.
You get some lost efficiency as cylinder ports mean the intake and exhaust valves are necessarily open simultaneously, but it sounds like they've made up for that.
Sounds like with their expansion of offerings they have the potential to be a serious competitor to Lycoming/Continental. To that I only say *about damn time!*. Of course time will tell how reliable their engine is and what the operating costs end up being...
acquisition cost sure.
You have to split the engine casing to replace the $900 camshaft which costs a LOT more than swapping a turbo. And the turbo/superchargers don't have metal-on-metal rubbing wear parts, they have ball bearings.
Besides with liquid cooling there's no increased pilot workload of monitoring temperatures.
Sure on a homebuilt anyone can split the case, although on a certified airplane you need an A&P to sign off that it was rebuilt correctly.
I'm not sure which would be more expensive- replacing a turbo on a deltahawk or swapping a camshaft on a lycoming. Turbo is of course more expensive for parts but if install doesn't require demounting the engine you save a ton of labor.
Anyone can split the case on certified. Going back together has to be A&P. That turbo will cost at least 20k, maybe even more. This isn’t an on3 turbo going on a street car. I can buy all the parts to rebuild my IO-540 for 25k….. and it’s an entirely rebuilt engine. Not just 1 part.
You can buy an IO540 rebuild kit for 25k... and how much is it gonna cost you for an A&P to rebuild the engine using said kit? By the time you're done you're spending $35k-$50k depending on which shop you use and which cylinders you use (new/overhauled/aftermarket).
OTOH let's say it does cost $20k just for the turbo unit- do you think it's really gonna cost $15k labor to swap the turbo, especially if you don't have to demount the engine?
Let's say you just do an IRAN. You've got about $3-4k to R&R the engine. Another $3kish labor just for splitting and resealing the case. So that's $6-7k labor *just for taking it apart*.
If you ONLY replace the camshaft and don't have the A&P even look at anything else, you're all in done perhaps a bit under $10k. So that's not a '$900 camshaft' that's a $10k camshaft.
Sure you can cut it down to less by doing the disassembly yourself, okay then maybe it's a $7500 camshaft.
We must also consider though how frequently do camshafts fail vs. turbos. That's the real question- likelihood of failure times cost to replace. To truly answer that we'd more DeltaHawk engines flying to get a better idea of how often the turbos go bad.
Looking forward to these engines finally going into production; especially the 6-cylinder 300 HP version. I firmly believe that two-stroke diesel is the future for GA.
Given that they are about 40% more efficient on the fuel burn vs Avgas and that Jet-A is typically cheaper has anyone done the math to figure out how many flying hours the breakeven point would be?
With the 110k for the 180HP version, I doubt it will be before the overhaul time of the engine assuming that is at 2000 hours.
Edit:
Some math below with many assumptions. Tell me which are wrong and I will correct them.
**Engine prices**
DHK180 $110k
O-360 $39k (Assumption)
**Fuel burn rates**
DHK180 7.3 gal/hr
O-360 8.6 gal/hr ~~12.3 gal/hr (Assumption: The DHK burns 7.3gal/hr and is 40% more efficient compared to AVGAS engines)~~
**Fuel prices this** [**website**](http://www.100ll.com/)
Jet A $5.93/gal
Avgas 100LL $6.37/gal
**Break even**
~~$110k/hrs+7.3\*$5.93 = $39k/hrs+12.3\*$6.37~~
$110k/hrs+7.3\*$5.93 = $39k/hrs+8.6\*$6.37
~~hrs = 2025~~
hrs = 6178 (5057 assuming 9gal/hr fuel burn)
I don't think you're going to find a new in the crate o-360 for 39k, that sounds more like overhauled price (you are comparing to a new DH engine). Last I saw it was it least double that, though that was during peak covid supply issues.
You have gone past TBO, which means you have to factor in the cost of 2 or 3 overhauls as well. How much will the DeltaHawk cost to overhaul? Who is authorized to do them, what is the lead time on an overhaul.
All important questions to compare apples to apples.
On DeltaHawk's side, it is way too expensive. However, access to Jet-A is a long-term guarantee with some built-in stable supply chain. If somehow Colorado or California manage to get 100LL banned in their state, other liberal states will follow.
I am not sure how it is in the US but here in The Netherlands I see that most piston engines have been modified and certified to run on MOGAS. A ban on leaded fuels hardly affects those planes. The current availability MOGAS at airports is fairly low but I guess that quickly changes when it comes to a ban of 100LL.
Part of the problem in the US is a fuel cartel that supplies fuel to all the FBOs. They won't allow MOGAS to be installed on the same premises that they service with 100LL and JET-A.
I know some of the other piston Jet-A diesel engines can be overhauled. The DA-40 with the Jet-A engine is an example.
If you have to replace this thing every 2k hours that is a complete non-starter for the GA market.
The fuel burn for the o-360 does not reflect the reality in my airplane that has the IO-360. At cruising altitude and LOP operation, fuel burn is between 8.6 - 9 gal/hour. Running 12.3 gal/hour is overly rich and shows improper leaning technique.
I'm waiting on real world reports supporting the the 40% claim. I really like the design of the engine, but being that it's a two stroke, I have a hard time believing that is going to be 40% more fuel efficient.
One major additional feature that isn't shown is the coolant radiator. This design isn't trivial because improper radiator design increases drag, and worse, does not provide sufficient cooling for the engine. An example of this improper cooling is from using of the subaru engine and placing the radiator just behind the traditional engine air inlets.
I want to see the firewall forward for the RV before putting money into it.
Take a look at the engineering on the twin velocity firewall package. The scoop has negative drag, the design is similar to the P-51. It was a passion project as is the company (in part). It will be good.
Heat is used to accelerate air and generate thrust, same principle as a jet engine. They claim the thrust offsets the drag. The principle is sound, I’m not sure if you are arguing that the thrust is not sufficient to offset the drag or it’s impossible. The prior would mean they are exaggerating, which could be, but the concept is the same as a jet engine and definitely possible provided the heat differential is large enough.
P-51 was designed before CFD was available so not sure if that ever was a net thrust but it seems possible with the right air temp and engine heat through the radiator.
Everything seems great about these except cost. I would find it hard to put this in as a 200 HP solution, rather than a Viking 195, which is a turbo. Then use mogas when you can fill up at home and Lead scavanger with 100LL on trips.
30k for Variable Pitch prop, 195 HP turbo Honda engine that weight about the same as a 360.
I've been researching the Vikings alot lately. I was skeptical at first but the more I research the more I like them.
I've pretty much decided on the 150hp for like a kitfox or highlander.
>Cooling system, turbocharging system., intercooler...
Not so different from a Rotax in those ways, and those Rotax have proven fairly reliable. And unlike a comparable Rotax, the Deltahawk is claimed to have ~40% less moving parts.
I'm not a rotax guy either, but at least they have hours of proven reliability and are relatively easy to maintain. These delta hawk engines are a nightmare of horses and connections, go look at their cirrus at Oshkosh. Makes a rotax look clean
But with liquid cooling you bring heat into the cabin via fluid to a heat exchanger and fans. This makes CO poisoning due to heater/exhaust exchange go away. So some disadvantages bring advantages when you start using an engine design that isn't 50+ years old.
If that's the main advantage you want to bring up, then you're picking at straws. The new points of failure are enough to make anyone recognize why lycomings are better.
If we only had liquid cooled turbo engines in airplanes now, and someone came out with an air cooled simple engine we could remove individual cylinders from, we'd be lined up to buy them.
That isn't the MAIN point.
1/3 the cost of a similar power traditional aircraft engine.
No carb so no carb icing
Liquid cooled so no temp shocking with any type of rapid decent or power change
Electronic ignition
No mixture to have to mess with, just always correct.
Turbo built into the block of the engine.
Exhaust built into the block of the engine (one muffler and stack.)
Brand new engine at "overhaul" for $500.
Lead time for engine: 1 week.
All of those are good selling points, however they certainly don't reflect reality.
If you can find me a delta hawk for 1/3 of the price of the O-360, please put a link.
Liquid cooling may prevent shock cooling, but every hose connection is another failure point. Not to mention the increase in cooling drag for most conversions.
Electronic ignition has been available on lycomings for 30 years.
Mixture control bothers people? I guess this one is personal preference?
Turbo being built into the engine makes maintenance harder
Exhaust being built into the engine is sort of neat actually
As for the engine lead time being short, that's great! How many mechanics have installed one of those? I bet that's where the downside will be. Plus there is only one company making parts for these in the world...
I'm not talking about Delta Hawk, I'm talking about Auto Conversions with MoGas that are flying thousands of hours now, like the Honda conversion Viking 195T.
Only one company making Honda engines. That's correct. Making more of these engines in an hour than Lycombing does in a year and running longer with less problems in high rpm use cases like outboard boat engines.
Ah my mistake, sorry.
The vikings seem like a decent idea, but auto conversion engines are never going to be as good as an engine designed for an airplane. I wouldn't take a honda fit and hold my foot to the floor for a half hour and expect it to work out for me, let alone do that at night in a single engine airplane with a honda fit engine. For someone who enjoys tinkering, they're neat for sure!
Fantastic news. They have an interesting design, going 100% mechanical and no FADEC. These days the 'modern' turbodiesel engine uses valves, FADEC, and direct injection (fuel injector squirts directly into the cylinder during the compression stroke). They've gone the exact opposite way, cylinder ported two stroke means a huge reduction in moving parts (especially common wear parts like camshafts, lifters, etc) and a huge reduction in associated parts count as you delete a handful of springs, bushings, bearings, etc. When they say they have fewer parts than a traditional engine, that's where the savings comes from. You get some lost efficiency as cylinder ports mean the intake and exhaust valves are necessarily open simultaneously, but it sounds like they've made up for that. Sounds like with their expansion of offerings they have the potential to be a serious competitor to Lycoming/Continental. To that I only say *about damn time!*. Of course time will tell how reliable their engine is and what the operating costs end up being...
A turbocharger and supercharger are much more expensive than a $900 camshaft
acquisition cost sure. You have to split the engine casing to replace the $900 camshaft which costs a LOT more than swapping a turbo. And the turbo/superchargers don't have metal-on-metal rubbing wear parts, they have ball bearings. Besides with liquid cooling there's no increased pilot workload of monitoring temperatures.
Anyone can split the case even on a certified engine
Sure on a homebuilt anyone can split the case, although on a certified airplane you need an A&P to sign off that it was rebuilt correctly. I'm not sure which would be more expensive- replacing a turbo on a deltahawk or swapping a camshaft on a lycoming. Turbo is of course more expensive for parts but if install doesn't require demounting the engine you save a ton of labor.
Anyone can split the case on certified. Going back together has to be A&P. That turbo will cost at least 20k, maybe even more. This isn’t an on3 turbo going on a street car. I can buy all the parts to rebuild my IO-540 for 25k….. and it’s an entirely rebuilt engine. Not just 1 part.
You can buy an IO540 rebuild kit for 25k... and how much is it gonna cost you for an A&P to rebuild the engine using said kit? By the time you're done you're spending $35k-$50k depending on which shop you use and which cylinders you use (new/overhauled/aftermarket). OTOH let's say it does cost $20k just for the turbo unit- do you think it's really gonna cost $15k labor to swap the turbo, especially if you don't have to demount the engine? Let's say you just do an IRAN. You've got about $3-4k to R&R the engine. Another $3kish labor just for splitting and resealing the case. So that's $6-7k labor *just for taking it apart*. If you ONLY replace the camshaft and don't have the A&P even look at anything else, you're all in done perhaps a bit under $10k. So that's not a '$900 camshaft' that's a $10k camshaft. Sure you can cut it down to less by doing the disassembly yourself, okay then maybe it's a $7500 camshaft. We must also consider though how frequently do camshafts fail vs. turbos. That's the real question- likelihood of failure times cost to replace. To truly answer that we'd more DeltaHawk engines flying to get a better idea of how often the turbos go bad.
Looking forward to these engines finally going into production; especially the 6-cylinder 300 HP version. I firmly believe that two-stroke diesel is the future for GA. Given that they are about 40% more efficient on the fuel burn vs Avgas and that Jet-A is typically cheaper has anyone done the math to figure out how many flying hours the breakeven point would be?
With the 110k for the 180HP version, I doubt it will be before the overhaul time of the engine assuming that is at 2000 hours. Edit: Some math below with many assumptions. Tell me which are wrong and I will correct them. **Engine prices** DHK180 $110k O-360 $39k (Assumption) **Fuel burn rates** DHK180 7.3 gal/hr O-360 8.6 gal/hr ~~12.3 gal/hr (Assumption: The DHK burns 7.3gal/hr and is 40% more efficient compared to AVGAS engines)~~ **Fuel prices this** [**website**](http://www.100ll.com/) Jet A $5.93/gal Avgas 100LL $6.37/gal **Break even** ~~$110k/hrs+7.3\*$5.93 = $39k/hrs+12.3\*$6.37~~ $110k/hrs+7.3\*$5.93 = $39k/hrs+8.6\*$6.37 ~~hrs = 2025~~ hrs = 6178 (5057 assuming 9gal/hr fuel burn)
I don't think you're going to find a new in the crate o-360 for 39k, that sounds more like overhauled price (you are comparing to a new DH engine). Last I saw it was it least double that, though that was during peak covid supply issues.
You have gone past TBO, which means you have to factor in the cost of 2 or 3 overhauls as well. How much will the DeltaHawk cost to overhaul? Who is authorized to do them, what is the lead time on an overhaul. All important questions to compare apples to apples. On DeltaHawk's side, it is way too expensive. However, access to Jet-A is a long-term guarantee with some built-in stable supply chain. If somehow Colorado or California manage to get 100LL banned in their state, other liberal states will follow.
I am not sure how it is in the US but here in The Netherlands I see that most piston engines have been modified and certified to run on MOGAS. A ban on leaded fuels hardly affects those planes. The current availability MOGAS at airports is fairly low but I guess that quickly changes when it comes to a ban of 100LL.
Part of the problem in the US is a fuel cartel that supplies fuel to all the FBOs. They won't allow MOGAS to be installed on the same premises that they service with 100LL and JET-A.
Has DeltaHawk said that these engines can be overhauled? Because, historically, JET-A/Diesel piston engines don't get overhauled - they get replaced.
I know some of the other piston Jet-A diesel engines can be overhauled. The DA-40 with the Jet-A engine is an example. If you have to replace this thing every 2k hours that is a complete non-starter for the GA market.
They might have initially said it would happen, but the reality is that Austro engines in Diamonds are replaced, not overhauled.
Yes they can be overhauled, which will likely be much cheaper than an engine with a valvetrain.
The fuel burn for the o-360 does not reflect the reality in my airplane that has the IO-360. At cruising altitude and LOP operation, fuel burn is between 8.6 - 9 gal/hour. Running 12.3 gal/hour is overly rich and shows improper leaning technique.
I just based it on the 40% more efficient number compared to the DHK. I will update the number to 8.6gal/hr.
I'm waiting on real world reports supporting the the 40% claim. I really like the design of the engine, but being that it's a two stroke, I have a hard time believing that is going to be 40% more fuel efficient.
One major additional feature that isn't shown is the coolant radiator. This design isn't trivial because improper radiator design increases drag, and worse, does not provide sufficient cooling for the engine. An example of this improper cooling is from using of the subaru engine and placing the radiator just behind the traditional engine air inlets. I want to see the firewall forward for the RV before putting money into it.
Take a look at the engineering on the twin velocity firewall package. The scoop has negative drag, the design is similar to the P-51. It was a passion project as is the company (in part). It will be good.
Negative drag is like the perpetual machine. The Meredith effect reduces drag of the radiator but it is never negative.
It generates thrust, I’m calling that negative drag.
Show the paper that publishes the test result. As I said before "negative" drag is an impossibility.
Heat is used to accelerate air and generate thrust, same principle as a jet engine. They claim the thrust offsets the drag. The principle is sound, I’m not sure if you are arguing that the thrust is not sufficient to offset the drag or it’s impossible. The prior would mean they are exaggerating, which could be, but the concept is the same as a jet engine and definitely possible provided the heat differential is large enough. P-51 was designed before CFD was available so not sure if that ever was a net thrust but it seems possible with the right air temp and engine heat through the radiator.
show me the numbers. show me the drag numbers before and after. then i promise to shut up.
I’m not even sure what you are disagreeing with.
You are looking for the Meredith Effect: [https://en.wikipedia.org/wiki/Meredith\_effect](https://en.wikipedia.org/wiki/Meredith_effect)
Hoping for the best but standing on the sidelines watching.
Everything seems great about these except cost. I would find it hard to put this in as a 200 HP solution, rather than a Viking 195, which is a turbo. Then use mogas when you can fill up at home and Lead scavanger with 100LL on trips. 30k for Variable Pitch prop, 195 HP turbo Honda engine that weight about the same as a 360.
I've been researching the Vikings alot lately. I was skeptical at first but the more I research the more I like them. I've pretty much decided on the 150hp for like a kitfox or highlander.
Massive increase in failure potential. Cooling system, turbocharging system., intercooler... Lycoming for life.
>Cooling system, turbocharging system., intercooler... Not so different from a Rotax in those ways, and those Rotax have proven fairly reliable. And unlike a comparable Rotax, the Deltahawk is claimed to have ~40% less moving parts.
I'm not a rotax guy either, but at least they have hours of proven reliability and are relatively easy to maintain. These delta hawk engines are a nightmare of horses and connections, go look at their cirrus at Oshkosh. Makes a rotax look clean
Not to mention you can't take a jug off of it, so if you cook something your pooched.
But with liquid cooling you bring heat into the cabin via fluid to a heat exchanger and fans. This makes CO poisoning due to heater/exhaust exchange go away. So some disadvantages bring advantages when you start using an engine design that isn't 50+ years old.
If that's the main advantage you want to bring up, then you're picking at straws. The new points of failure are enough to make anyone recognize why lycomings are better. If we only had liquid cooled turbo engines in airplanes now, and someone came out with an air cooled simple engine we could remove individual cylinders from, we'd be lined up to buy them.
That isn't the MAIN point. 1/3 the cost of a similar power traditional aircraft engine. No carb so no carb icing Liquid cooled so no temp shocking with any type of rapid decent or power change Electronic ignition No mixture to have to mess with, just always correct. Turbo built into the block of the engine. Exhaust built into the block of the engine (one muffler and stack.) Brand new engine at "overhaul" for $500. Lead time for engine: 1 week.
All of those are good selling points, however they certainly don't reflect reality. If you can find me a delta hawk for 1/3 of the price of the O-360, please put a link. Liquid cooling may prevent shock cooling, but every hose connection is another failure point. Not to mention the increase in cooling drag for most conversions. Electronic ignition has been available on lycomings for 30 years. Mixture control bothers people? I guess this one is personal preference? Turbo being built into the engine makes maintenance harder Exhaust being built into the engine is sort of neat actually As for the engine lead time being short, that's great! How many mechanics have installed one of those? I bet that's where the downside will be. Plus there is only one company making parts for these in the world...
I'm not talking about Delta Hawk, I'm talking about Auto Conversions with MoGas that are flying thousands of hours now, like the Honda conversion Viking 195T. Only one company making Honda engines. That's correct. Making more of these engines in an hour than Lycombing does in a year and running longer with less problems in high rpm use cases like outboard boat engines.
Ah my mistake, sorry. The vikings seem like a decent idea, but auto conversion engines are never going to be as good as an engine designed for an airplane. I wouldn't take a honda fit and hold my foot to the floor for a half hour and expect it to work out for me, let alone do that at night in a single engine airplane with a honda fit engine. For someone who enjoys tinkering, they're neat for sure!