Ahhh EWP's....
PL always had such an unreasonable hate-on for EWP's based on
nothing but theory that it drew my attention to them. Long ago
on this list there was another Aussie named Leon Promet who was
a proponent of them and as such was a target of PL vitriol. So
while I am a believer in research and number crunching myself,
when I see other using them successfully in other applications,
I assume that some of the assumptions we make in our theories
may be flawed and at the end of the day a theory holds nothing
against real world experience.
So I figured enough talking, somebody had better try it,
so I did.
I'm using all Davies Craig stuff, which is from down under.
I'm currently running with the new electronic controller
and 2 pumps. The primary pump is speed controlled by the
controller which has a secondary output for switching on of
their electric radiator fans. I use this output for the
secondary pump since I already have a big-ass fan up front ;)
When I previously flew, I also had a secondary pump on a
manual switch just as a fail-safe (since PL had predicted I
would fall out of the sky into a very special hell). My very
first pump did seize once during ground running, so I got
another but when I disassembled the first pump for inspection
I found a flaw with the seal which was easy to fix, so that
was the one I decided to use as a secondary pump.
The original pump controller I had was functional but
basic, so I decided to update with the new one and I ended up
getting one with a pump, so I have a spare pump sitting on the
shelf, which I figured is not a bad idea.
I also installed an EBP (small electric boost pump) in
the heater line to address a problem that was probably unique
to my climate and flying style.
My instructor at the time was a friend who was flying
for NATO over in Afghanistan (2 months in, 2 out) and he had
taught me the benefits of their mandatory approaches over
there of staying above 10K till above the secure area then
doing a hard slip all the way in (too avoid small arms fire).
I found this to be ideal up here in the sparsely populated
north so that you'll always make the runway (but I recognize
that is not acceptable in a crowded traffic environment), so
that became my defacto standard approach, weather permitting.
However in cold weather during the long slip in with the
engine at idle, the EWP controller would almost stop in order
to keep the engine at temp (can't do that with a Lyc), just as
a thermostat would also close, unfortunately that also stopped
giving me cabin heat and I'll tell you it got cold fast! Now
I'm used to dealing with winter weather (I embrace it
actually, as I love winter sports), but when you are dressed
lightly in a cramped cockpit because you have an abundance of
clean heat (unlike an exhaust heat muff), then suddenly that
heat is gone, you are gonna start looking for solutions. So I
bought the Davies Craig EBP which was cheap, small (almost
kinda cute really) and easy to put in.
Now I'm not gonna beat the EWP drum and say the benefits
mean that everybody should put one in, but against PL's most
dire predictions, it did work. It solved a few design
challenges, while presenting a few other ones. But nothing
overwhelming, just like any of the ones that it solved.
Now I'll be the first to say that I haven't flown in
years, due to so many other factors that are attributed to
life in general, but PL may or may not attribute that to the
EWP, but H2O cooling really wasn't one of my issues when I was
flying. Sure I could only manage to sustain full throttle for
3 minutes while climbing all the way to 10K, (from 2200)
before heat would be an issue, but my ducting was far less
optimal than I hope it is now.
But I think PL just chose to ignore me and pretend that
it never happened, which is fine with me as I really don't
follow him or his preaching. I hadn't even thought of him in
years... did he ever build an airplane???? Or is it just still
a theory??
Anyways, I'm happy with my choice, but it's not snake oil
that will cure all your ills. However they do work. Check them
out.
Todd.... electron dependent