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Last Sunday’s flight was a series
of 20 minute hops, picking up friend, flying to brunch, dropping off, back to
base. Couldn’t learn a lot about tuning; except to be disappointed.
I had in the past been quite pleased
with the mixture tuning. A few flights back I replaced the O2 sensor. Two
flights back I then did a re-tuning by flying a full profile from takeoff to
landing in auto-tune mode, except for occasional checks of temps, etc. That’s
when I found it going very rich around the bin 32 area on descent, then having
to re-tune for it to run right on the ground.
I assumed all was good when heading out
on Sunday. Except even with the mixture knob at 2:00 – 2:30 position
it was too lean pretty much all the time – had to increase mixture knob
to get toward max power. During a brief session of lean cruise, I changed the
throttle a bit, and it was suddenly so lean the engine was faltering. Hm-m-m.
Apparently auto-tune had not done things right on prior flight. OK; track
mode on EM2, mode 9 on EC2 for auto-tune; but no joy; nothing would change. Re-set
things again; auto-tune would not work.
On each of the 4 descents the EGT tripped
the warning light. RPM was about 4500-4800; max EGT 1730-1760. Unfortunately, didn’t
note MAP; but it was likely pretty low.
Back on the ground by the hangar, I
again tried the auto-tune – it WORKED. Why not in the air?
So I have some work to do, and some questions.
Why during the auto-tune flight would
the mixture be leaner than previously tuned? Could it be more resistance to ground
at the O2 sensor due to more anti-seize grease? Or something else?
When in auto-tune, does program knob
more clockwise cause it to set a more rich profile; or would the stochiometric then
be with the mixture knob set more clockwise as well – or vice versa?
Are both mode 2 and mode 6 different
than 2-3 years ago? My mode 6 is secondary injector differential adjust.
Is it time for another EC2 upgrade?
I've never had the problem myself since I always plan my descents to
avoid windmilling the engine at low throttle (that's not good for the RD-1x
drive).
The Velocity is a very slippery
airplane, so I’d have to make very shallow descents to avoid neutral or
negative thrust on the prop, at least until I’m below gear-down speed. What
does it do to the re-drive?
Al G
I
tried to address this issue with Mode 6, the adjustable MP threshold for the
lower map table range. The idea is to have the lowest in-flight MP select
the 0 - 31 range and ground condition select the upper range (32 - 64).
Being successful at this also requires the rpm threshold of the low range be
chosen correctly and everyone's seems different so it may not be right for your
installation since it is not programmable. Controllable pitch props
also complicate this issue, even on carbureted engines. It's the
same situation that causes P51's to fart, pop and belch fire during this phase
of flight. Everybody thinks that's cool tho....
I've never had the problem myself since I always plan my descents to avoid
windmilling the engine at low throttle (that's not good for the RD-1x
drive). It's also a waste of the potential energy in altitude.
But, if the EGT's are the only problem during this condition, I'd ignore it
because you can't damage anything in the engine at this low power setting.
Tracy
On Sat, Feb 12, 2011 at 1:09 AM, Al Gietzen <ALVentures@cox.net> wrote:
Relating
to this subject heading; here is an issue that has me wondering.
I
tune the EC2 MAP table at the low end – maybe up to 14-15” MAP
– while on the ground; and then tune above that in flight. And
frequently when on rapid descent with throttle pulled well back; the engine
alarm light starts blinking. It’s because EGT is exceeding the
limit (I think 1750). Seems strange. I figure must be really rich, and fuel
burning at the exhaust port making high EGT.
So
one day I put it in auto tune mode and pull back the throttle on descent, and I
note that the mixture in bins 30-31-32 going way to the rich side; I think it
was bin 32 that was full rich. No longer a high EGT alarm. Hm-m-m; must
be it was really lean there, but why would that make high EGT.
Then
I land; and as I pull off the runway the engine is rough and stumbling. Lean
out the mixture and it works fine. So I do some auto tuning at low rpm and MAP,
and find it at those low 30’s bins making it much leaner and get things
running smoothly.
So
what’s happening here; and is there a fix. Clearly those bins need
to be tuned for low rpm and taxi operation. Why the high EGT on throttle
back descent? How do I not get the engine alarm on descent, and still get to
run smoothly on the ground?
Al
-----Original Message-----
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]
On Behalf Of Tracy
Sent: Friday, February 11, 2011
8:04 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: EC2/
Tracy
Yes, if you
decrease the Mode 3 value you will have to increase the map table values across
the whole range to compensate. It's not automatic though, you will have
to do it manually. Auto tune would eventually get it adjusted too but
that assumes you run the engine at all possible settings for long enough for
that to happen. That's why it pays to do Mode 3 first, Mode 2 second and
Mode 1 (or 9) 3rd. Don't ask why I numbered the Modes in that order, I
don't have a good answer other than Mode 1 was the one that would be used most
often. Now Mode 9 is the most often used but Mode 9 didn't exist in the
early days of the EC1/2/3.
Last thing to do is auto tune for the fine tuning.
Tracy
On Fri, Feb 11, 2011 at 10:09 AM, <bktrub@aol.com> wrote:
I
didn't run out of injector setting range, but am very close. My edit page
bar graph is pretty much ony one or two lines high for most of
the Map table. I'm also down to values around -120 for most of the addresses.
I thought about setting mode 3 a bit lower.Iif so, and I then go back and
re-tune it to the aproximate fuel/air settings I have now, does it change the
bar graph and the values at each address?
Say,
for instance, MAP address 80 shows a setting of -118, and only one line on
the bar graph. If I lower the injector setting in mode 3 and re-tune to the
same mixture setting, will the setting be higher than -118 and will the bar
graph be higher? It would be nicer to be closer to the middle values, rather
then the bottom (-127) or top (+127), so I have more adjustability in the
future if I were to need it for some reason. Even though it runs nicely now,
i'm still up around 8 "o"s on the horizontal mixture graph.
-----Original Message-----
From: Tracy <tracy@rotaryaviation.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Fri, Feb 11, 2011 6:38 am
Subject: [FlyRotary] Re: Replaced Tension Bolt, Oil Seal, Thrust Bearing ...
back ...
turns out it was running really rich on the
factory EC2 settings. I went to auto tune and the injector settings went way
down, all the way up and down the map table.
Glad you got it running better Brian. When you run into the
situation you mentioned above, the first thing you should do is adjust the
Injector Flow Rate (Mode 3). That will adjust the mixture at ALL throttle
settings and is a lot easier than resetting the entire MAP Table. But as
long as you don't run out of range on the MAP Table adjustments, what you did
will work OK.
Tracy
On Thu,
Feb 10, 2011 at 8:06 PM, <bktrub@aol.com>
wrote:
And on
to brighter news. I went out today, did some tuning on my plane, turns out it
was running really rich on the factory EC2 settings. I went to auto tune and
the injector settings went way down, all the way up and down the map table. Had
to do a little fine tuning, and especially at the staging point, had to richen
it up there, at bin # 84. I would have taken it up for a flight, but had other
appointments. It was a glorious day for flying, but a test will have to
wait for the next nice day here in Seattle.Previous flights went OK until just
after takeoff, then the engine would surge and backfire, getting the attention
of all witnesses within a mile or two. I can imagine that they were all
mentally formulating what they were going to say to the FAA investigation team.
I was starting to question my decision to go rotary, but now have a renewed
sense of confidence in the installation.
Temperature
today was around 50 degrees, even with extended running on the ground at full
throttle, temps maxed out at 145 and148 for oil and coolant respectively.
Throttling back to 16 inches of MP got the temps running around 125. Going to
wait until summer to close up my cooling inlets a little.
Sent: Thu, Feb 10, 2011 4:50 pm
Subject: [FlyRotary] Re: Replaced Tension Bolt, Oil Seal, Thrust Bearing ...
back ...
Hmm, send money overseas
for their oil so that we can increase our trade deficit and fund all sorts of socially
constipated cultures who might be hostile to our own, or keep the money
here and employ americans? That's a real head scratcher there. I've got some of
the mineral rights in the Bakken, due to some forward thinking ranch owning
ancestors, so you can imagine what my feelings on this are.
New Drilling Method
Opens Vast U.S. Oil Fields
Published
February 10, 2011
A new
drilling technique is opening up vast fields of previously out-of-reach oil in
the western United States, helping reverse a two-decade decline in domestic
production of crude.
Companies
are investing billions of dollars to get at oil deposits scattered
across North Dakota, Colorado, Texas and California. By 2015, oil executives
and analysts say, the new fields could yield as much as 2 million barrels of
oil a day -- more than the entire Gulf of Mexico produces now.
This new
drilling is expected to raise U.S. production by at least 20 percent over the
next five years. And within 10 years, it could help reduce oil imports by more than half, advancing a goal that has long
eluded policymakers.
"That's
a significant contribution to energy security," says Ed Morse, head of
commodities research at Credit Suisse.
Oil
engineers are applying what critics say is an environmentally questionable
method developed in recent years to tap natural gas trapped in underground
shale. They drill down and horizontally into the rock, then pump water, sand and chemicals into the hole to crack the
shale and allow gas to flow up.
Because
oil molecules are sticky and larger than gas molecules, engineers thought the
process wouldn't work to squeeze oil out fast enough to make it economical. But
drillers learned how to increase the number of cracks in the rock and use
different chemicals to free up oil at low cost. "We've completely
transformed the natural gas industry, and I wouldn't be surprised if we
transform the oil business in the next few years too," says Aubrey
McClendon, chief executive of Chesapeake Energy, which is using the technique.
Petroleum
engineers first used the method in 2007 to unlock oil from a 25,000-square-mile
formation under North Dakota and Montana known as the Bakken. Production there
rose 50 percent in just the past year, to 458,000 barrels a day, according to
Bentek Energy, an energy analysis firm.
It was
first thought that the Bakken was unique. Then drillers tapped oil in a shale
formation under South Texas called the Eagle Ford. Drilling permits in the
region grew 11-fold last year.
Now
newer fields are showing promise, including the Niobrara, which stretches under
Wyoming, Colorado, Nebraska and Kansas; the Leonard, in New Mexico and Texas;
and the Monterey, in California.
"It's
only been fleshed out over the last 12 months just how consequential this can
be," says Mark Papa, chief executive of EOG Resources, the company that
first used horizontal drilling to tap shale oil. "And there will be
several additional plays that will come about in the next 12 to 18 months.
We're not done yet."
Environmentalists
fear that fluids or wastewater from the process, called hydraulic fracturing, could
pollute drinking water supplies. The Environmental Protection Agency is now
studying its safety in shale drilling. The agency studied use of the
process in shallower drilling operations in 2004 and found that it was safe.
In the
Bakken formation, production is rising so fast there is no space in pipelines
to bring the oil to market. Instead, it is being transported to refineries by
rail and truck. Drilling companies have had to erect camps to house workers.
Unemployment
in North Dakota has fallen to the lowest level in the nation, 3.8 percent --
less than half the national rate of 9 percent. The influx of mostly male
workers to the region has left local men lamenting a lack of women. Convenience
stores are struggling to keep shelves stocked with food.
The
Bakken and the Eagle Ford are each expected to ultimately produce 4 billion
barrels of oil. That would make them the fifth- and sixth-biggest oil fields
ever discovered in the United States. The top four are Prudhoe Bay in Alaska,
Spraberry Trend in West Texas, the East Texas Oilfield and the Kuparuk Field in
Alaska.
The
fields are attracting billions of dollars of investment from foreign oil giants
like Royal Dutch Shell, BP and Norway's Statoil, and also from the smaller U.S.
drillers who developed the new techniques like Chesapeake, EOG Resources and
Occidental Petroleum.
Last
month China's state-owned oil company CNOOC agreed to pay Chesapeake $570
million for a one-third stake in a drilling project in the Niobrara. This
followed a $1 billion deal in October between the two companies on a project in
the Eagle Ford.
With oil
prices high and natural-gas prices low, profit margins from producing oil from
shale are much higher than for gas. Also, drilling for shale oil is not
dependent on high oil prices. Papa says this oil is cheaper to tap than the oil
in the deep waters of the Gulf of Mexico or in Canada's oil sands.
The
country's shale oil resources aren't nearly as big as the country's shale gas
resources. Drillers have unlocked decades' worth of natural gas, an abundance
of supply that may keep prices low for years. U.S. shale oil on the other hand
will only supply one to two percent of world consumption by 2015, not nearly
enough to affect prices.
Still, a
surge in production last year from the Bakken helped U.S. oil production grow
for the second year in a row, after 23 years of decline. This during a year
when drilling in the Gulf of Mexico, the nation's biggest oil-producing region,
was halted after the BP oil spill.
U.S. oil
production climbed steadily through most of the last century and reached a peak
of 9.6 million barrels per day in 1970. The decline since was slowed by new
production in Alaska in the 1980s and in the Gulf of Mexico more recently. But
by 2008, production had fallen to 5 million barrels per day.
Within
five years, analysts and executives predict, the newly unlocked fields are
expected to produce 1 million to 2 million barrels of oil per day, enough to
boost U.S. production 20 percent to 40 percent. The U.S. Energy Information
Administration estimates production will grow a more modest 500,000 barrels per
day.
By 2020,
oil imports could be slashed by as much as 60 percent, according to Credit
Suisse's Morse, who is counting on Gulf oil production to rise and on U.S.
gasoline demand to fall.
At
today's oil prices of roughly $90 per barrel, slashing imports that much would
save the U.S. $175 billion a year. Last year, when oil averaged $78 per barrel,
the U.S. sent $260 billion overseas for crude, accounting for nearly half the
country's $500 billion trade deficit.
"We
have redefined how to look for oil and gas," says Rehan Rashid, an analyst
at FBR Capital Markets. "The implications are major for the nation."
Read more: http://www.foxnews.com/us/2011/02/10/new-drilling-method-opens-vast-oil-fields/#ixzz1DZa3M891
-----Original Message-----
From: hoursaway1@comcast.net
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, Feb 10, 2011 4:26 pm
Subject: [FlyRotary] Re: Replaced Tension Bolt, Oil Seal, Thrust Bearing ...
back ...
All this was said 40 years ago.
"""We will be out of oil in twenty
years""" Coffee is bad for you""" now
coffee is good for you & we have more oil than anyone ever dreamed
available + being used many times more efficiently, the
"""ones in the know ...do not know!!!! But they can
predict the weather 50 years from
now.
David R. Cook RV6A Rotary -4 deg. F. Lansing MI.
----- Original Message -----
From: "David Staten" <david.staten@gmail.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Thursday, February 10, 2011 2:15:02 AM
Subject: [FlyRotary] Re: Replaced Tension Bolt, Oil Seal, Thrust Bearing ...
back ...
Well, I
can agree with Lynn for one thing.. Carter was 2nd worst president ever....
(After Bush 43)... :P
Ethanol
in fuel was never about efficiency. NEVER. It was about replacing a very toxic
oxygenate (MTBE) with something cleaner burning and less toxic. Lead in
aviation fuel will go the same way.. its inevitable. One plant makes the lead
that goes in it. They go tits up and the 25 percent of the aviation fleet
that burns 75 percent of the leaded avgas will be knee-capped brutally.
Biofuel
is not exclusively ethanol. Its also HYDROCARBONS synthesized or processed from
living matter, as opposed to fossil fuels naturally developed from long dead
matter. Its bacteria in a digester/reactor with a feedstock and a product
stream. Ethanol is in cars to reduce smog.. nothing more. Biofuels in aircraft
do not necessarily have to include ethanol (but it could).
Ifwe
dont start doing more than paying lip service to preserving our environment, we
will have the worlds best military protecting the worlds largest ecological
wasteland.
As long
as we are overly dependent on fossil fuels, we will be subject to the
foreign policy of others. Biofuels, Nuclear, Solar, Wind, Hydroelectric... all
things that need to be developed further. And if we wait until its too late to
transition, our worlds best military will be reduced to throwing rocks and
writing nasty letters, because our turbine powered planes and tanks dont run on
good intentions.
Personally... if we have to burn oil... Why burn mine (ours) when I can
burn yours (theirs)..
I'm not
hardly a hairy, stoned, tree hugging hippie, but I do recognize their point..
On Wed,
Feb 9, 2011 at 7:24 PM, <hoursaway1@comcast.net> wrote:
Lynn for President,,,,,,,,,,( might be in central FL this winter,
will contact, stop & say hi ) David R. Cook
RV6A Rotary.
----- Original Message -----
From: Lehanover@aol.com
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Wednesday, February 9, 2011 1:39:57 PM
Subject: [FlyRotary] Re: Replaced Tension Bolt, Oil Seal, Thrust Bearing ...
back ...
Interesting
enough, though the scary part is there’s no mention in the text of AVGAS
or GAS … only the subject uses the term AVGAS.
The
text body uses the terms “unleaded,
sustainable general aviation fuel, credible renewable, unleaded fuel, 'green' fuel and the exclusive
use of biofuel in air show performances." I fear this is another attempt to push ETHANOL or
heavy ethanol-blended fuel.
If you
take away government subsidies from the green fuel tree hugger play. Gasohol
would be gone in a month. It takes almost a gallon of fuel to produce a gallon
of gasohol. You have to boil it. It is made just like Jack Danials.
It is
the biggest victory of form over function ever imagined by mankind.
The
farmers love it because they save money as the kernel quality is lower, and the
water content is higher, and they get government money. The government pays the
oil companies to use it. The oil companies get to displace actual gasoline with
the crap for even more profits, and the user pays all of them extra in taxes so
you can get 30% less mileage and performance. But wait...........there's
more.........Plus the better corn not now being grown for feed stock plastics
and human consumption has boosted the price of that corn. So the farmer profits
again. The beef man looses his a__, and you pay even higher beef, pork and
poultry prices in addition the taxes that support this house of cards. When
beef prices get high enough, dairy herds are thinned at higher rates (younger)
and milk production drops. Milk prices go up.
Send
the entire energy department home. Established in 75 to eliminate our
dependence on offshore oil.
Eliminate
all farm subsidies. Phase out oil imports to zero over the next 7 years. Drill
here. Drill now.
We can
be cut off at the knees and turned into a 3rd world country by the towel heads
who hate us. If you don't remember the oil crisis of 74 under the (Now) second worst
president in this country's history, Jimmy Carter, Look it up. Long lines on
odd license number days, or even license number days for 10 gallons of fuel.
The
worlds strongest military reduced to writing nasty letters?????
If the tree
huggers want to live in mud huts, smoke dope, and use gasohol let them pay for
it with their money not mine.
Look up
Bakken oil formation.
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