Jarrett,
I know it will be tough to build my requirements, but with liquid cooling it should be possible.
Smart ducting (I hope the smart part does arrive at my place sometime....), exhaust augmentation, should make it possible.
I am in this for the fun of building and tinkering. My job gives me enough time in the air.... so going flying soon is not the driving force.
Also, I do believe your (commercial) ride could be made to be okay on the temps, as it is certified, cost will play the major drum.
Just for curiosity, does the 414 have rounded lower exit corners at the firewall? ...or is this one of those jobs where the hot air and exhaust exit on top?
I choose "any speed", because I read all these reports about getting hot (short of overheating? :)) on climb, leveling off to cool, alright on cruise.
I understand that excessive cooling will cause drag, but that's where I plan to use "airflow control".
CMIIAW - a overspilling frontal intake will not produce any more drag than if there would be no intake at all.
Same with Naca - if there is no flow through the Naca (and it is built correctly) there should not be a lot of drag.
For my BD-4 the Naca is probably no good, but for any canard it will work if you take care of details.
I believe in the "package" - the best intake will not work if the exit is no good - and everything in between.
Sometimes I hear the "too complex" excuse. Look around and copy someone that works.
Augmentation may be more complex to build, but there are no moving parts. A cowl flap is simple device, although - it moves :))
In the end you will spend a lot more time to rebuild your simpler system over and over again.
TJ
On 5/22/07, Jarrett & Heidi Johnson <hjjohnson@sasktel.net> wrote:
I have no horse in this race at this time, however something that Thomas wrote struck me funny. If this is the standard to which we should be building our a/c then the Certified C414A that I fly in [one of my day job's] wouldn't fit it in two area's.
A) I had a 1hr 47min idle on the ground in KLAS [waiting to be #1 for dept] here a few weeks ago, I finally had to ask the tower to let me turn into the wind as my oil temp's were getting too high.
C) If I was to climb out at just over Vmca I KNOW that the cylinders would hit over redline in under the five minutes. I don't know why someone would do this as Vx and Vy are both up around 100-120knts [Vmca=79knt] but you did say ANY speed... Anyway, just another data point to hold up to the light and compare w/ what you guys see as a need and a want..
Jarrett
Personally I believe that a cooling system should be able to:
a) Run indefinite on the ground - like long waiting cues on taxi ways, any wind direction
b) Support a min 1 min full power run-up
c) Support a min 5 min Max Power climbout at any possible speed (slower being the worst....)
I'd rather play with movable cowl-flaps, etc. than accepting that I might not be able to pull full power at any point.
What if you are already maxed out, because OAT is high, you are heavy, in a nasty turbulence and have to do an "emergency" climb out.
You have an engine, that could do it easily, ....if you had a system that would cool it.
Plan starts with rereading all cooling posts, get the calculator, get familiar with heat transfer tables, plan on spending some serious money for custom coolers....
Plan is to built for the worst case. I always can reduce cooling....
Thomas
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