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Long Coot October 16, 2010

By petehdgs - Posted on 22 January 2011

Saturday, October 16, 2010

Since the last log entry I have done a LOT of research into Aircraft Diesel engines that are or will soon be on the market.  The main move to the diesel was prompted by my observation at Kentmorr marina and Kent Narrows marina that diesel fuel was available at both, but 87 octane pump gas was the only gasoline available.  Also, at Bay Bridge Airport Jet A was selling for $3.30 per gallon while 100LL was $4.55, and highway diesel in our area is $2.90-3.30 depending on where you buy.  Unlike gasoline aviation engines, which cannot tolerate lower octane fuel easily, diesel engines designed & rated for Jet A can tolerate #2 diesel fuel with only slight modifications to the fuel supply system.  In fact running these engines on #2 diesel will provide slightly better power and fuel economy.  When you consider that diesel fuel or jet A are available nearly everywhere, it makes sense to go with diesel. 

At this time there are currently NO diesel engines available, but within one to 3 years there will or should be three: SMA, Centurion, and Deltahawk.  Of these three, I think Deltahawk is the best way to go.  What follows is a discussion of each and their strengths and weaknesses, and why I think Deltahawk is the best option. 

SMA SAFRON Group is a large company is in France and has designed a direct drive, air-cooled O-4TA called the SR305-230.  It is rated at 230 HP, and maintains 200 HP from 5,000-10,000 feet.  Its service is ceiling 12,500 feet and it weighs about 450 pounds dry.  I think this is a good choice for the Long Coot, but they are not selling engines now and will not consider a pusher application.  They have 48 engines flying world-wide and are redesigning their engine to address problems found during in-service operations.   They will not support any fuel other than Jet A. 

Centurion engines are made in Germany.  They have a 2.0 4 cylinder at 155 HP, 300 pounds and a 4.0 V8 at 355 HP and 600 pounds.  These engines are flying in Europe and have accumulated a total of 2 million flight hours.  They are based on automotive diesel engines and are water cooled with chain drive reduction to the prop.  These might be a good choice, but no engine is available in the 230 HP class and the 350 HP unit is too heavy in my opinion. 

Deltahawk is a small company in Racine Wisconson.  It is in the final FAA certification stages for a V4 two-stroke diesel engine sort of like the old Detroit Diesel engines from GM.  These engines are direct drive with belt driven roots-blowers and turbochargers.  They are cylinder ported only, with no valves in the head, and have a mechanical pump & nozzle Bosch fuel injection system.  They are very compact, rugged and light weight, especially considering they are water cooled.  The 200 HP engine is 327 pounds dry, 202 cubic inches, rated 200 HP @ 2700 RPM to 18,000 feet.  Their primary emphasis is getting their first engine family certified and into production at this time, but once this is complete they will be offering more engine options like V8 and V6 engines with a wide variety of power settings available.  They have already tested this engine in pusher, tractor, and vertical mount helicopter applications and their attitude is the sky is the limit with this engine package.  I have called the factory in Racine and spoken with the president and what a great conversation it was!  They are actively pursuing the experimental market and I think that this is the way to go for the Long Coot Amphibian!  

Monday, November 01, 2010


I have also looked into water injection for diesel engines.  Snow Performance in Woodland Park, CO has a system available for most truck applications.  Water only injection will increase HP 10-15% on the same fuel burn.   100% water will cool combustion and EGTs and will increase power approx 20-30 HP.  75/25 water/methanol will reduce EGTs and power will increase approximately 40 HP, or about 20%, and 50/50 water/methanol will reduce EGTs and increase power approximately 70+ HP, or 35%.  On the 200 HP Deltahawk engine this means 230-270 HP.  


The Snow Performance Boost Cooler® Diesel Stage 3 MPG-MAX™ water/methanol injection system provides more power, cooler EGTs, and excellent fuel economy increases. The MPG-MAX™ system does not require a sustained high load state in order to provide maximum fuel economy gains. The MPG-MAX™ system uses a new injection management controller that allows for a small spray of water/methanol to be injected across the power curve. This provides an increase in combustion efficiency which provides more power without injecting more fuel. This is possible because water that becomes steam expands more than dry air. This increase in efficiency translates into an increase in fuel economy. Typical fuel economy increases are 10%-15% or 1-3 MPG in a truck, and about 0.9-1.3 GPH in an airplane at 75% cruise. 


The MPG-MAX™ system has a secondary output that is used to activate a Power Mode. This introduces a second phase of injection. A larger nozzle(s) is used to inject more fluid to make more power. The Power Mode activation point is adjustable for best performance. Because the MPG-MAX™ system injects more frequently, the fluid

consumption rate will be higher than other Boost Cooler systems. The MPG-MAX™ system has been coupled with the Snow Performance 7 Gallon Reservoir to provide a large fluid tank that fits well into the bed of a truck. This will provide the longest range possible and includes the necessary installation hardware.


I received the FAA Registration for the Long Coot Amphibian N225XC. 

We cut 12 trees last week in preparation for building the garage. 



Friday, December 17, 2010


Today we replaced our old heat pump with a new 2.5 ton 15 seer model.  We are keeping our old heat pump for use in our new garage when it is finished.  It will be used to keep the humidity and temperature maintained in the garage so the wood can be maintained at the correct water content for building. 


The garage hasn’t been started yet, but permits have been issued and the ground was marked by miss utility.  REC was contacted about the power cable and they have decided the power cable must be moved.  They are sending a release form for that, but it isn’t in yet.


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My favorite epoxy? Progressive Basic No-Blush Epoxy

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