DeltHawk Under New Ownership

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TarDevil

Well-Known Member
For way more years than I care to count this company has been saying "Certification next year."

100 new employees are being added. Maybe we will finally see an alternative (although expensive) engine.

Ruud Family and DeltaHawk | Delta Hawk Engines

Toobuilder

Well-Known Member
HBA Supporter
Log Member
I suppose next they will partner up with Moller for his new Skycar...

stol

Well-Known Member
It has been vaporware for the general public... Rumor had it they were making hundreds of motors for military drones and selling them to the DOD for 10 times the advertised rate....

I was one of their first fans... put my name on the priority list for delivery, offered to R&D a Zenith 801 installation,, All I got was tomorrow, tomorrow, tomorrow...

I have asked them numerous times to REMOVE the pic of my plane they use on their website, both by email and in their face at Oshkosh.... Last I looked it is still there...

I hope they ramp up and produce a viable product, my gut feeling is they will take deposits and then go bankrupt.... Time will tell..

Himat

Well-Known Member
It has been vaporware for the general public... Rumor had it they were making hundreds of motors for military drones and selling them to the DOD for 10 times the advertised rate....
Then, what UAV made by the hundreds does have a "un named" diesel/heavy fuel engine?
The engine size tell us we should look for an UAV the size of the Predator or slightly larger.
I'll try a new search, but while searching UAV engines to find suitable light aircraft engines I have newer seen a trace of the DeltaHawk engine.

stol

Well-Known Member
Then, what UAV made by the hundreds does have a "un named" diesel/heavy fuel engine?
The engine size tell us we should look for an UAV the size of the Predator or slightly larger.
I'll try a new search, but while searching UAV engines to find suitable light aircraft engines I have newer seen a trace of the DeltaHawk engine.
That was the "line" they fed me at Osh for years......

Of course the said deliveries are "next week" for experimental people to get their motors... And that went on for years... YMMV.

TFF

Well-Known Member
They would love to sell drone engines to governments. No liability and sell a $40,000 engine for$200,000. They were probably too slow. Small turbines are being popped out everywhere for this now. Cool always wins. Cox model airplane engines was sold about a half a dozen times, each company leveraging. The value of the product in the end could not keep up with the next potential leverage. It collapsed. If you start with something only $20,000,000 can make work, you are not going to find many investors. I bet the buy-in was way less than they ever dreamed. Designing anything for the score is always shaky. If they could have put out a solid 10 engines a year for ten years, they could have had a resume to leverage. At$50,000 a new engine, Cessna would have bought 100s even though it would be costing $15,000 more than a 4 cyl Lycoming. Every foreign sale would have had one. The$200,000 Continental engine they are trying to pass on is a joke.

TarDevil

Well-Known Member
I was one of their first fans... put my name on the priority list for delivery, offered to R&D a Zenith 801 installation,, All I got was tomorrow, tomorrow, tomorrow...
I remember reading an article about you and your plane years ago, that you initially wanted to use a DeltaHawk engine. I certainly understand now why that didn't work out.

Looks like your picture is gone now!

rv6ejguy

At $65K plus, and similar BSFC figures as a Lycoming running LOP, there is no GA logical business case for this engine in North America. Makes sense for the military who want everything to run on diesel or Jet fuel and cost is of no consequence or where avgas is way more expensive or unavailable like Europe or Africa. When I prodded these folks on VAF several times for technical clarifications, they were either silent or evasive and finally went away after further eroding their reputation after the years of delays. It's clear, they are not interested in experimental aviation anyway. It seemed it was a perpetual R&D exercise, keeping many people on the payroll bankrolled by outside investors. autoreply Well-Known Member At$65K plus, and similar BSFC figures as a Lycoming running LOP, there is no GA logical business case for this engine in North America. Makes sense for the military who want everything to run on diesel or Jet fuel and cost is of no consequence or where avgas is way more expensive or unavailable like Europe or Africa.
Mogas is more and more common and more and more engines become available that can run Mogas, including ethanol. That'll take away even the last business case.

Does digital ignition let you get away with pretty awful (low octane) gasoline? If so, car gas in africa would also work just fine.
When I prodded these folks on VAF several times for technical clarifications, they were either silent or evasive and finally went away after further eroding their reputation after the years of delays. It's clear, they are not interested in experimental aviation anyway. It seemed it was a perpetual R&D exercise, keeping many people on the payroll bankrolled by outside investors.
I've actually found that to be the easiest criterium to determine whether people think their product will work out.

cheapracer

Well-Known Member
Log Member
I think it's scandalous, outrageous and downright despicable that a company would announce an engine and later show nothing.

rv6ejguy

Well-Known Member
Mogas is more and more common and more and more engines become available that can run Mogas, including ethanol. That'll take away even the last business case.

Does digital ignition let you get away with pretty awful (low octane) gasoline? If so, car gas in africa would also work just fine.

I've actually found that to be the easiest criterium to determine whether people think their product will work out.
Well, it does seems that some people will buy a diesel for no really good reason other than they like diesels or think it would be cool to run on Jet A. They don't seem to care about initial costs.

For engines with a genuine high octane requirement, there will be some hp loss in using mogas regardless of the ignition system used but our largest aviation market now is converting Lycoming engines over to digital electronic ignition where the majority runs mogas most of the time. We can tailor the ignition curves so that cruise efficiency is better and there is no or minimal impact on takeoff power when operating on mogas, assuming compression ratios under 8.5 to 1. The Rotax and Jabirus actually work better on mogas anyway.

H.Evan'sRV7A

Well-Known Member
I have been struggling to believe their claims and they have not been willing to clarify them. On their "engines" page they claim that a 200 hp DH powered RV7 at 75% can go 244 mph. My calculations strongly suggest that if you were foolish enough to fly that airplane that fast (think VNE 200 kts) it would require 231 HP at 8000'. In what math system is 231 75% of 200?

They also say it will do 75% on 8.5 gph. Diesel fuel weight about 7.49 pounds per gallon vs about 6.0 for avgas. So lets convert to pounds and we get 8.5 x 7.49 = 63.665 pounds and if we divide that by the weight of avgas we get about 10.5 gph which is almost exactly what they say the normal, gas powered version does.

I have asked them about their claims of greater efficiency before and so far they are not making any sense. The way the content copied is a little messed up but you can see it fairly well below.
Engines | DeltaHawk Engines

 RV7/7A (1) DeltaHawk TD RV 7/7A IO-360

 Fuel Burn gph @ 75% (3) 8.51 10.5

 Max Cruise Speed sm@75% 244 207

TFF

Well-Known Member
I have a feeling they were trying to extrapolate 75% power from a naturally aspirated to one that is I think both supercharged and turbo. Pretty much no understanding of strength and aerodynamics, just horsepower. Looks like they cleansed the website.

Yankee Aviator in SC

Well-Known Member
I remember visiting Deltahawk back when Doug was first tinkering with the engine on his Velocity. 1995 or 1996? Odd business this modern day engine development game must be. I remember he had all kinds of warning signs, reward posters and photos of some "corporate secret thief" all over the facility. Nonetheless, I was impressed with his engineering abilities and especially his prototype engine at the time. After a few years went by without a certification award however, I remember thinking, either he's no longer looking to get it certified, or he can't solve the hurdles (in flight restart was one issue that made the press years ago). I think the world moved on for a time. Nice to see someone attempting again.

H.Evan'sRV7A

Well-Known Member
They are sort of cheating on the TAS by using 8000 for the normally aspirated gas engine and 18,000 for theirs. Their engine can maintain full power to 18k. The airplane needs the same HP at the same altitude to go the same speed, plus or minus a little for weight, etc. If they were using 8000 for theirs they would have to throttle it to get back to 75%.
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I have been struggling to believe their claims and they have not been willing to clarify them. On their "engines" page they claim that a 200 hp DH powered RV7 at 75% can go 244 mph. My calculations strongly suggest that if you were foolish enough to fly that airplane that fast (think VNE 200 kts) it would require 231 HP at 8000'. In what math system is 231 75% of 200?

They also say it will do 75% on 8.5 gph. Diesel fuel weight about 7.49 pounds per gallon vs about 6.0 for avgas. So lets convert to pounds and we get 8.5 x 7.49 = 63.665 pounds and if we divide that by the weight of avgas we get about 10.5 gph which is almost exactly what they say the normal, gas powered version does.

I have asked them about their claims of greater efficiency before and so far they are not making any sense. The way the content copied is a little messed up but you can see it fairly well below.
Engines | DeltaHawk Engines

 RV7/7A (1) DeltaHawk TD RV 7/7A IO-360

 Fuel Burn gph @ 75% (3) 8.51 10.5

 Max Cruise Speed sm@75% 244 207

rv6ejguy

Well-Known Member
Turbo engines can give amazing speeds at altitude if they have a high critical altitude however diesels require very high high pressure ratios to make any power in the first place. On the good side, this is a 2 stroke design and they run a supercharger and a turbo. We had a couple turbo Subaru RVs which could easily exceed Vne above 8000 feet at less than 45 inches and only 40 inches at 12,000 feet, probably 35 inches at 18,000 feet.

Lots of their other claims and comparisons were complete nonsense on the old website and I when I called them out on them on VAF, they evaded most of the questions or posted more nonsense.

Perhaps- perhaps, they will get their act together under new ownership and come clean on the numbers. I'll wait though, \$65K+ with nearly the same BSFC as a Lyc running LOP,a bit more weight and no track record in service or with TBO ain't gonna bump Lycoming out of business any time soon.

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