Hi Guys,

After all you might be interested to see here in this link how the Upload is Used,
maybe some of you have done that or maybe not yet, check this:

http://h1069662.hobbyshopnow.com/pro...e=1252-ART.xml

and here are some of the pictures, just to make the point for you to spend
few minutes at least on that approach and make more use of the Upload,
not just to measure it indeed, and comment on it, the title is
"Unparalleled Performance".

Cheers,
Nick

[link=http://home.wanadoo.nl/pereivers/regulated_fuelsupply/a_regulated_fuel_supply.html]This [/link]setup does about the same, at a fraction of the trouble you have to go to with the Webra system. Webra tries to, in a simplified way, reach the results of fully computer controlled lean burn modern automotive engines. I would call that a pipe dream. Nice to fill an idle evening with. It is not economical feasible to incorporate such a system in our model engines, unless a two servo system can be programmed into a pic-processor BY THE MANUFACTURER, and not by the end user. The engine then comes with a carb and two servos as one unit, not to be tampered with. (or equivalent system)

I am a bit sad, but also a bit amused about the reactions concerning my last post. I think, No, I am convinced, that theory (if proven it becomes law!) is the only one way to approach things. If something happens, there is a cause for it to happen. Knowing as much causes as possible opens up a spectrum of solving possibilities. Knowing less causes makes it easier to define one's point of view, but that need not be the right one. Now. 40-some years after that first knowledge clash, I have come to the understanding how little we are allowed to learn. Theory can be learnt in a very short time. Without it there would be no progress, because the little we are allowed to learn in a lifetime would not be sufficient to increase the level of thinking as laid down by our predecessors.

Pe-- Do not be upset, I don't think anyone is knocking how valuable scientific theory is or what you have said. I will give is simplistic example.
If you gave two people a problem which you needed to solve, one came up with a theory of how it should be solved and the other had already done it many times before. Which persons advice would you be inclined to follow.

Likewise Pe........I did not mean it as an insult at all. It takes both in my opinion. Theory and hands on experience. At one time my son was writing programs in the defense industry. The math that boy knows just blows me away. I wish I new a fraction of what he does. But once the theory is all hammered out, it still has to be put into practice. That's where the inevitable problems are found....

I think Pe misunderstood --
from a logical standpoint -- theory is just that - till proven
then the theorists can dissect the "proof " and determine the laws which are involved.
call it reverse engineering if you like -- the theories on tuned pipes I have read range from excellent to counterproductive - mostly --the latter.

There are ideas - theories, postulates , on and on - add nauseaum.
without actual demonstration of the entire idea,none of these is W A S.
School-- is supposed to explain the unknown and ideally ( dream on ) encourage use of and expansion on known info.
but an unproven application of a theory is just a S W A G.

Hi Pe,
As you see everybody has his own view on the Theory/vs/Practice. I think both, your Dad and you were right, each on his own way.
He was using life experience, kind of Intuition, or call it an Intelligent Look-up-Table built in his brain and based on Products he has
seen. In fact he used the Calculations which some other engineers have made and produced those boilers. You proved that he did
the right thing to support your studies in a way or another, although the funny thing is that he took decision prior cashing on his own
investments for your education. I think it is the same for many of us. Also, we as parents do not quite allways behave in the way
we are expected by our children. And there is an EQUILIBRIUM point, when the Kid is turned into Midle Age person when there is
huge "Look-up-Table" in his brain and also that is based on advanced Education OR huge Experiemental practice. I will never
ever say that Engineer is more Valuable than Technician and the OTHER WAY ARROUND = BOTH of them ARE needed, one
with Mostly-Calculations the other One with Mostly-Look-up-Table. Then we come to the Nomination of a Person with Highly
Successful Educated Guesses which might be a nice mix of both. All is up to the age, interest as well the speed and the Way
of accumulating skils to solve something.

For example, loot at you nice Calculator for Propellers. I do not think that you will see many of us taking Laptop to the Airfield.
I am printing kind-of-Look-Table for my particular Engine and there the Calculations stop. Then for some friend arround with
different engine I will give some "smart" hint based on my "intuition" which is in fact Your Calculations Impact on my thinking.
So, there we are, I behave like your Dad did, although some smart kid on the Aifield will have Excel Data sheet running on his
Palm-top computer, I might be faster with my "look-up-table". In fact as we all know the Look-Up-Tables are the FASTEST
ways in many Computers to do some of theis functions, Who is Calculating for example math-functions on pocket calculator,
it will take forever and will "eat" the battery and the result is known already for some N x 100 years, for example no anyone
of us (maybe) would start to calculate how much is SIN(0.5) isn't it or better to ask how much is SIN(30deg).

Cheers,
Nick

Well, just to remind also something: - How do you call the age when our Smart Guesses/Intuition cause more disasters than results ?
I think that is the Retirement age when our Look-up-Table is getting out of use more and more. It is comming guys, for some sooner
for some later, at the end - for anyone at some age... For example, the intuition of anyone of my Grand Fathers for buying Typewiter
would be quite useless nowadays ... i.e the Post-Equilibrium age when the END is nearer than the Beginning. Sorry, if I made some
of you a bit said, but we have to face it sometime ...(myself I am well above 40), that is the Beginnig of the End, admiting it or not ...

Some blame Winston Chirchil for saying: The men are on the Age the Feel like, while the Women are on the Age they look like ...
That is maybe why some ladies are telling that some men never grow up...
(of course I believe there are no Ladies reading this and if there are, please blame the UK former PM in years around 1944)

Cheers(anyway),
Nick

What the f--- makes experience nothing but a guess?
Who do you think came up with the info for the text books?

Well since this topic is going off the deep end I want to give my 2 cents worth.

I figure that the engines I power my planes with will unload enough in the air to go way past their top static prop speed. The planes are certainly aerodynamic enough. The hughe carbs on them should allow the engines to go to their limit. And the large props are certainly holding them back while running fullspeed static. So when run full speed level in the air or shallow dive I expect a 6500 static engine to get close to 10,000 rpm.

Assumptions apply to a,

BME115 in a SD Katana
3W56 in a GP Extra

But not to a ZDZ50 in a GP Ultimate---Too much drag

It seems then even simpler than Webra solution would be to use a "Smart" On-board Glow Plug driver.
Because the changes in RPM will change the Glow-plug Temperature, that will be "printed" on the Ohmic
Resistance on the Glow Plug and so on.
I.e. the Question is then:
- Is there well programable Microcontroller inside of some glow-plug-drivers which can be used to
optimise the Engine in the Air, especially in that Upoad RPMs, instead using for that
the Webra system ?

I guess in the Gas-engines that is well in use for the electronic Ignition to advance the
spark timing. Thus, those better electronic ignition systems have such Inteligent feature
inside of the Ignition Micro-controller ?

Nick

The idea is nice but experience and theory shows -- that the way the glow plug is involved in firing an alky fuel - does not lend it'self to changing the TIMING of the burn.
first - increased revs in downlines is not a power increase -
If you are after more power -- use a spark , as it does not respond to increased temp/pressure in the engine.
Glow ignition does -which is why the fiddlin with lowered compression/thicker element wire /buried elements -on n on - to try to optomize the glow setup.
Experience -again has for me shown the spark setup with a little nitro n alky to be the easiest setup to produce the most usable ,controllable power.
the bi tch is that getting the carb right is tough as typically the existing carbs will not balance correctly , the fuel to air ratio -with a tuned exhaust .
The best setup I found was a closed loop system , using exhaust pressure from the pipe to increase pressure at the tank- enrichening the mix as the power (andheat ) sharply increased - self regulating and it DOES work -unlike some of the horribly expensive POS systems offered by various engine mfgrs.
On my setups this increase in pressure was on the order of 3/4 psi ( measured ) -for best results
the result was a perfectly smooth tractable power band from 1500-9000 static and not a lot of unloading in the air as the pipe acted as a governor
engine used ST2300 and propped with 18x8
which likely means little to any one but me anymore --

But what makes you think that downturn RPM-increase is increasing the temperature on the glow-plug ?

The temperature will increase if you pump more fuel proportionally to the RPM increase and that is what
happen if you are dependent on the pressure in the exhaust pipe.

On contrary, if you are not dependent on that pressure, the glow plug temperature should go even lower
beside the RPM increase, because of the increased amount of air in the mixture. I.e. that would lean the
engine without (!) overheating it.

In other words that pipe pressure makes sure that the engine does not go lean in downtuns and burns
more fuel so you have to throtle back, which most of the pilots do.

Thus, the Microcontroller inside of the onboard driver might do better job and you do not have to throtle
back; the RPMs will go high but the engine will stay as cool as on normal RPM even more cool maybe.
This should be measured indeed.

strange--
the increase of fuel to air DECREASES temps and cools the plug
downlines cool the engine --as it is working less relative to rpm. When you throttle up -increaseing fuel and air - you are asking the engine to do more work -which is the real reason temps want to climb. and why I used the closed loop setup of tank pressure .
also -as a glow engine is throttled back -in a downline the carbs typically deliver a richer mixture - which is primary reason for th classic flameout at bottom of a split S (as an example

The carbs do this simply because if there was NOT a slightly rich mix at of idle -the engine would go too lean and kill as work load increases. in the case of the good old four strokers they would /will backfire and/or toss the prop

when you start looking at what pipes do/do not do --remember the work being done ,determines the temperature --in any IC engine glow engines are great, simple devices but they change timing as temp pressure changes - they have no choice in the matter. by adding fuel you can always reduce the temp tho the pipe is increasing the pressure .
this is required as work is increased ( pulling uphill) but on a down line, things cool off rapidly and the naughty carbs tend to drop temps such that a flameout can easily happen.
the old OS pumped setups from the late 80's early 90's were horrible in this respect .

You are right. But thats what an education is. A study of other peoples experiences so you don't have to repeat it to be able to do the job.
Mathmatical calculations are only as good as the ability of the individual calculating to apply them to the task.
I am currently doing safety of flight tests on the 787 Flight Control Software. There are lots of people here that have lots of experience but most of the work has been done by calculations by individuals just recently out of school.

jeeze -it has come to that ?
checking the unknown using calculations performed by the untested?

( I like that- )