Bill,

I love questions like this, you've already done the heavy lifting and
pretty much nailed the merits. The merits start to look even better
when you examine the possibilities of putting a clutched shaft on your
existing turbo and electrically spin the compressor side as required
(reduces weight, gains you the HP that is always being sucked up by the
blower which is compressing air at a much lower efficiency than the
turbo, etc.) There are also a mess of other possibilities that while
more complex from an engineering standpoint offer "better" solutions for
certain mission profiles. These include compressed air starts, fully
electrical turbos, clutched superchargers, centrifugal or screw
compressor supercharges instead of roots type, the list goes on.

The selection of our current solution was a combination of the desire
for mechanical redundancy, the use of off the shelf parts (off the shelf
5 years ago mind you), and the need for something that didn't require a
huge amount of engineering effort to shoe horn into our package. That
said, undoubtedly this is one of the areas that will see modification as
time passes, and it wouldn't surprise me in the least if 5 years from
now there is a DeltaHawk model that in addition to the electric turbo
has full FADEC fuel control, an electric water pump, and an integrated
starter/generator. Imagine what that will do to the weight and fuel
efficiency. Additionally, due to the modular design of all of these
components on the DeltaHawk, all of these items are a external to the
engine case and for the most part are a bolt on proposition.

Dave Driscoll
DeltaHawk LLC


Bill Daniels wrote:

Dave, I like the Deltahawk package the way it is, but I do have a
hypothetical question.

What are the merits, of lack thereof, of using an electrically boosted
turbocharger to supply combustion air for starting or flight idle? It would
seem, at first glance, to be a simpler and lighter solution than using both
a roots supercharger and a turbo in series.

Bill Daniels


"Dave Driscoll" wrote in message
...


All,

In addition to being an lurker and occasional poster on RAH, I also
happen to be one of the engineers responsible for the DeltaHawk (or the
sole reason the engine hasn't been in full production for the last 3
years according to the marketing guy). In any case, as this is one of
my few areas of RAH expertise, I'd be happy to answer any questions that
people may have regarding the project.

The web site

www.deltahawkengines.com

is generally pretty up to date, but there are certainly always specific
questions that a FAQ won't answer.

Dave Driscoll
DeltaHawk LLC

geo wrote:



Here's an interesting new diesel engine with much lower operating costs.
Looks like it would fill the bill for a Glass Goose (which I'm


considering)


very nicely. Waddya think? http://www.deltahawkengines.com/object00.htm