





This page last updated on
01/26/2019.
Copyright © 2001-2019 by Russ Meyer
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article is still under development...
Since my Second Trip to Washington in 1998, my family had grown. Instead
of two kids, Jane and I now had four. If I was to continue doing
cross-country flying vacations, I would have to fly a plane large enough to
carry all the kids. That meant a six-place airplane.
It's not easy finding a six-place airplane to rent. People just rarely
need that much load hauling capacity, and six-place airplanes are expensive.
After scrounging around my local FBOs, I found one with a Cessna T210.
A T210 is a real performance airplane. It flies high and fast, carrying
well over a half ton of payload. Compared to the Cessna 172s I had been
flying, it was mighty machine! The thought of flying it was rather
intimidating. I decided that I needed to upgrade my training to a commensurate
level.
I embarked on a training program to better my flying skills, earning an
instrument rating and a commercial certificate. Along the way, I also
accumulated a lot time in retractable gear aircraft. I spent several hours
flying the T210 with an instructor and got checked out. After all that, I
felt I was ready to pile my family into an aircraft and blast off for parts
northwest.
Our first family flight was an evening dinner trip to Spinks airport in south
Fort Worth. We just buzzed around
the local area, stopped for a bite at Spinks, and did some night landing
practice before heading for home. I felt totally at ease with the
plane and was ready to plan a flying vacation to Washington state. Little
did I know that was the last time I'd fly the T210. After two years
of preparation and planning, I was shocked to learn that my FBO had sold the T210.
Well, it wasn't the end of the dream, I just had to make an adjustment. The only other six place plane
available was a tired, flight-worn Beechcraft A-36. Although A-36s are
regarded as sweet airplanes by most pilots, this one was definitely not
a cream puff. It had all kinds of extra equipment installed and, as
a result, was heavy. So heavy, in fact, that I couldn't load the whole family in the
plane without pushing gross weight limits. The CG was tricky; only a
couple of passenger loading arrangements were tolerable. All in all, it
was a poor candidate for the trips I wanted to take.
There was a Piper Cherokee 6 available for rent at the North Texas Flying
Club that could conceivably handle the task. I hesitated in pursuing
that option. I'd heard the Cherokee 6 wasn't a good instrument platform.
Just gaining access to the thing meant I had to pay monthly dues, go through a
check-out process, and log 10 hours flying it; that meant lots of dollars. Besides, I'm a Cessna man a
heart.
Well, I was stymied and wasn't sure what to do for a few
months. I started working on getting checked out in the A-36. I flew
it a couple of hours with an instructor, and it was OK. I just wasn't
really excited about the airplane. Then, I discovered my FBO was about to
acquire a brand new Cessna T206. It's sort of like a fixed gear version of
the T210. Well glory be! It was even equipped with the Garmin G-1000
flat panel flight instruments.
When the T206 arrived, I was one of the first to get checked out in
it. I immediately began planning my 2006 flying vacation to Washington.
It was my parents 50th wedding anniversary, and I intended to fly up to
Washington for the festivities. We'd stay there for about 1½
weeks then fly down to California to spend a couple of days with Jane's parents.
After a month of planning, I was ready to tackle the task. Below is the
flight log of my trip. Almost the entire trip was flown on instrument flight plans.
Date |
6/24 |
ATC RADAR Track
(click to enlarge)
|
Leg |
Addison, TX ®
Liberal, KS |
Route |
TEXOMA8.ROLLS V210 |
Duration |
3.3 hours |
Log Comment |
Flew through sporadic light rain for an ILS 35 approach at Liberal. |
We arrived early at Addison and took our time getting ready for departure.
The plane was full of water bottles, an umbrella, piles of paper, old
banged-up oxygen masks, and a bunch of other non-essential gear. We
removed it all and stowed it in the van. Weight was critical, and I was determined to fly under
gross. Every six pounds we jettisoned meant we could carry another gallon of gasoline.
We fueled to the tabs plus eight gallons, giving 72 gallons useable fuel; a
bit more than four hours endurance at 65% power. The wind computations
said it would take 2½ hours to get to Liberal. According to the
forecast, liberal could have ceilings as low as 2500 feet when we arrived.
Four hours worth of fuel would give us a comfortable reserve just in
case we needed to shoot a couple of approaches.
We took off at 8 AM into partly cloudy skies. Leveling at 16,000 feet, I
throttled back to 65% power. In adjusting the fuel flow, I noticed the engine
seemed a bit rough.
Judicious fiddling smoothed things out a bit.
The fuel flow seemed excessively fussy.
An imperceptible movement of the control was all it took to get too rich or
too lean. In addition, we were burning fuel at a rate much higher than predicted
by the book. There was also a curious 80-120°C difference in
exhaust gas temperature (EGT) between even and odd numbered cylinders.
All these little quirks wore on my mind. Was something wrong with the
engine? All the gauges were in the green and the engine seemed
happy. Maybe the slight roughness, somewhat high fuel flow readings, and
offset EGT indications were normal. I
had only flown the airplane about a dozen hours up to that point and never
higher than 10,000 feet. I wasn't
entirely sure what to expect from it at 16,000. The engine seemed OK
and I wasn't running it very hard. I decided to just let it go and watch
the gauges carefully. If anything twitched, I'd land somewhere
immediately.
The winds aloft turned out to be stronger and from a different direction
than forecast. As a result, the trip took 3.3 hours rather than 2½.
About 15 miles out, we descended through broken clouds and light rain,
breaking out at 5000 feet. We flew visually to Liberal and shot the ILS
35 approach anyway, just for practice. We touched down, taxied in, and tied down. I
retired to the pilot's lounge to plan the next leg while the kids and Jane
raided the snack machine.
Since the whole family had been on oxygen on the way to Liberal, I had the
FBO top off the oxygen tanks. The oxygen gauge had read 1850 PSI when
we left Addison and was down to 675 PSI upon landing at Liberal. We
had used 1175 PSI of oxygen. That's a consumption rate of 420 PSI per
hour for six people, or 70 PSI per person per hour. Throughout the
entire trip at altitudes from 11,000 to 16,000 I found our O2
consumption pretty consistent at 70 PSI per person-hour. I found
that quite useful in anticipating our remaining O2
range while in flight.
Date |
6/24 |
ATC RADAR Track
(click to enlarge)
|
Leg |
Liberal, KS ®
Cheyenne, WY |
Route |
V210 to LAA, V263 to LIMEX, V611 |
Duration |
2.6 hours |
Log Comment |
In and out of broken cumulus near Denver. |
It was very hot in Liberal. After piling everyone in the plane, I
snapped on the air conditioner for a welcome blast of relief. The cool
air was nice, but the air
conditioner added almost 125 pounds to the plane. If it had been my
plane, I would have left all that junk on the ground. Air conditioners and small aircraft
just don't belong together.
I'm not sure Jane and the kids would agree.
We taxied out, got our clearance, and departed at about 1:00 PM local time.
The take-off roll seemed somewhat longer than expected, but I assumed that
was due to the heat. The density altitude was over 5000 feet.
When we were about 300 feet in the air, I looked down to scan the
instruments and discovered that I had failed to turn off the air
conditioner. Idiot! I should have turned it off before taking
the runway. The air conditioner uses significant engine power. I
immediately snapped it off. Maybe that's why the take-off roll was
longer than expected, but whether the AC was on or off didn't seem to affect the
climb rate. Sometimes little oversights like that can add up to a
wrecked airplane. I was determined to weed these "Doh!" moments out of
my flying. No sense in handing disaster an opportunity.
We bumped through thermal turbulence up to 10,000 feet, and cruised along with no worries.
After we were established on V263, just past Lamar VOR, ATC called with a
routing change. They wanted us to fly to Hugo VOR, over Falcon VOR, over downtown Denver to Gill VOR, and finally intercept V89 to
Cheyenne. I acknowledged and began programming the GPS for the route.
After a few more minutes, as we neared Denver airspace, ATC bumped us up to 11,000. We happily buzzed along, going in and out of little puffy
cumulus at our altitude. It was a bit bumpy, but at least the engine seemed to be
running well. Although there was still a curious difference between EGT
readings on even and odd cylinders, it was much less than the previous leg.
The engine anxieties seemed to have been left on the ground at Liberal.
ATC called again and asked why I was off course. I was perplexed...I
didn't see that I WAS off course; my GPS CDI needle was centered; I knew where
I was and where I was going. ATC handed me off to Denver regional
approach control. I studied the last routing ATC gave me and flipped
through the GPS routing I had programmed. Darn it! I had left the
LIMEX intersection in the waypoint list when I should have deleted it.
It was just an oversight. I had actually been flying a course that would
lead me to LIMEX when ATC had wanted me headed to the Falcon VOR.
Another "Doh!" moment! Well, that's why I was flying this whole thing
on instruments, to sharpen my skills and get some experience. Denver
gave me a series of vectors that sent us north along the eastern edge of
their Class B airspace. They finally let us go just east of Gill VOR
and cleared us direct to Cheyenne.
On arrival, Cheyenne tower had us enter a left base for runway 27.
We made our approach a little high which forced me to throttle back to idle
power for a minute or two on long final. After touchdown, as we were
rolling out, the engine died. I was totally shocked! As we
rolled to a stop, I attempted to restart a couple of times. It coughed
and sputtered, but I couldn't keep it running. I was embarrassed and
perplexed as I sat there on the active runway, trying to restart this
bafflingly rebellious machine. Finally, I reduced fuel flow and succeeded in restarting the engine. The engine was not happy, but we managed
to taxi off the runway. All the engine instruments were in the green;
according to them absolutely nothing was wrong. However, the engine
continued to miss and cough occasionally. During the long taxi to the FBO, I fiddled with fuel flow and found that when I reduced it further, the engine smoothed out. By the
time we reached the FBO, it was running normally.
This was quite exasperating, I had never before experienced this with an aircraft engine. As we retired to the FBO for a
refresher, I puzzled about the engine behavior. I tentatively concluded
that I had set the fuel flow entirely too rich given the density altitude.
The elevation at Cheyenne is about 6200 feet. It was pretty hot outside,
and ATIS was reporting a density altitude of 7600 feet. The pre-landing
checklist calls for a full rich fuel flow, and I had set the control
accordingly. With the engine idling on long final the turbocharger
dropped off-line. That resulted in an excessively rich mixture given
the density altitude. The excessively rich mixture may have also fouled the plugs. All
this explains why I couldn't start the engine until I reduced the fuel flow
(mixture too rich).
It also explains why the engine didn't idle smoothly until I had taxied a
while (fouled plugs).
Turbocharged engines can suck a lot of gas, so
the fuel flow adjustment can be set extremely rich; much richer than normally aspirated engines.
At full rich, a ton of gas is pouring into the cylinders. Normally,
with the turbo on-line, the engine has no problem burning all that gas.
However, with the thinner air and turbocharger off-line, full rich is just
way, way too much gas. So, at high altitudes with the turbo off-line,
you've got to lean the mixture. That certainly applies to ground
operations, but what about final approach? A long final with the
engine at idle is going to allow the turbo to spool down. Without the
turbocharger, the mixture will likely be way too rich
and the engine might choke. It might even die, leaving you in a lurch,
especially if you need to go around. After thinking about it a lot,
I've concluded that it seems best to leave things set at full rich, just in
case a go-around is required. However, you should also set
engine power high enough to keep the turbo on-line. That way, everything is in
place in case a go around is required. After landing, when the turbo
spools down, you should lean the mixture to avoid choking the engine.
Back at the FBO, I pulled out the operating handbook and read up on
high altitude engine ground operations. The manual recommended running
the engine up to 1200 RPM then adjusting fuel flow for smooth operation.
That seemed to confirm my suspicions. I concluded that the
source of my trouble was an excessively rich mixture. Still, I
planned to do a very careful run-up prior to
the next takeoff just to make sure everything was OK. I also planned to carefully
follow the engine operating recommendations for taxi to see if that helped. This whole issue
had never come up in my
check-out back home. We never went over high altitude ground operations
for turbocharged engines. That's something that should be
corrected in the curriculum.
Date |
6/24 |
ATC RADAR Track
(click to enlarge)
|
Leg |
Cheyenne, WY ®
Riverton, WY |
Route |
V138 |
Duration |
2.0 hours |
Log Comment |
Dodged thunderstorm near Casper.
Called for fuel. Nice lady @ RIW. Strong x-wind landing. |
Jane and the kids piled into a courtesy car and went off in search of lunch. I
stayed behind and began working on the flight plan for the
next leg.
I had been hoping to fly from Cheyenne, Wyoming to Idaho Falls, Idaho.
Checking the winds aloft revealed this plan was not so good. The winds
would be on our nose the whole way. The MEA for the route was 14,000
feet and the winds were pretty strong up there. The best we could
manage would be to arrive at Idaho Falls with a 30 minute fuel reserve.
That was just cutting it too close. If the forecast winds were
stronger than expected or from a slightly different direction, we'd be in
trouble. There were other considerations too, most importantly adverse
weather. There were scattered thunderstorms over western Wyoming.
If we needed to deviate around any of these it would add time to the trip
and we'd get in trouble with fuel again. There were almost no airports
along the route to Idaho Falls equipped with instrument approaches.
The trip would be conducted in late afternoon, approaching twilight lighting
conditions. As if that weren't enough, we would be flying over
unfamiliar mountainous terrain. Bad juju was trying to snowball on us.
This is exactly how a bunch of marginal little pieces of the puzzle
eventually clump into a disaster. Here's how the Snowball o' Disaster
builds: 1) The weather is poor and I have to deviate around a
bunch of little thunderstorms, 2) the deviations and/or adverse winds cause
the trip to take longer than expected, 3) enroute I realize we won't make
Idaho Falls with our remaining fuel, 4) instrument equipped airports are out
of range or socked in with weather, 5) we try to make a VFR approach to an
airport in the mountains but the visibility is poor because of weather or
twilight or a combination, 6) we impact an obstruction on approach to the
airport or run out of fuel mucking around. No, the direct to Idaho
Falls plan was no good..jpg)
We needed an alternate plan. I had done a lot of thinking about this
portion of the trip before leaving Addison. I decided that if the
winds were not favorable, I'd break this leg into two parts; Cheyenne, WY to
Riverton, WY, then Riverton to Idaho Falls. It was time to dust off
the ol' back-up plan and begin laying out the Cheyenne to Riverton leg.
RADAR revealed a large thunderstorm blocking the route to Riverton. I
watched the storm drift about over the next 30 minutes, and it didn't seem
to be moving much. That was encouraging; we should be able to dodge
it. Also encouraging was the fact that storms weren't popping up all
over. It was a slowly evolving situation so the weather probably would
not catch us by surprise. According to RADAR, there was also a little
thunderstorm just west of Cheyenne, drifting slowly to the east. It
would be over us soon, and we wouldn't be able to take off. I hurried
to gather weather data, lay out the route, and make my calculations.
Maybe, if Jane and the kids got back soon, we could get out of Cheyenne
before the thunderstorm caught us. I checked on the fueling status of
the airplane; they hadn't yet pulled the fuel truck around.
Soon, that small thunderstorm rumbled overhead and the rain began to fall.
Darn! We wouldn't be able to take off while it was in the neighborhood.
The fuel guys said they couldn't even pump gas while thunder was around; some
sort of regulation apparently. Ah well, we were going to be stuck here for
a while. Jane and the kids arrived with a pile of hamburgers. We
retired to the pilot's lounge for lunch and whiled away the hours as the thunderstorm
drifted lazily east..jpg)
Three hours later, the storm had wandered far enough away for the fuel guys
to go to work. As they pumped gas, I got a last minute weather update and
filed a flight plan. We would follow V138 all the way to Riverton.
That big thunderstorm in the middle of our route was still there, so we'd have
to deviate when we got in the neighborhood. Casper, Wyoming was just 50
miles northeast of our route and would serve as a backup, if we ran into
trouble.
Finally, the plane was gassed, the crew loaded, clearance received, and we
were ready to go. I started the engine and leaned it at 1200 RPM as
recommended by the book. We taxied just fine and the engine seemed happy.
I did an especially thorough run-up, carefully examining the gauges, checking
magnetos, etc. All seemed in great working order. I could see no
reason for concern at all. The engine was in good shape. I had flown
Cessna 172s in the mountains before and always leaned them on run-up for maximum
power. Out of force of habit, I did that now, noting a generous increase
in power with the engine leaned.
I taxied onto runway 13 and slowly throttled up to full power. The
engine responded well, and we were rolling. Manifold pressure good, RPM
good, oil pressure good, fuel flow increasing with engine power, all gauges in
the green. Verdict: continue take-off roll. We hit rotation
speed, I pulled back, and we were off climbing at best rate with over half the
runway ahead of us. Man, this 206 doesn't seem to notice high density
altitude at all. The take-off and climb were almost as good as if we were
back home at Addison. Climbing through 1000 feet AGL, I turned east to
set-up to intercept V138. Suddenly, the engine surged twice and power
dropped off. I pushed the nose over to level flight and looked around for
a landing area. I was basically on a wide left downwind for runway 27.
I could easily make it, if necessary.
Once I saw a safe landing was assured, I scanned the engine instruments and
controls. The fuel flow setting seemed too lean. I shoved it in full
rich, and the engine surged to life again, as though nothing had happened.
Whew...now, would it keep running? I again considered landing on runway
27. Scanning the engine instruments, all seemed OK. Everything in
the green. I throttled back to cruise climb power and adjusted the fuel
flow for 20 GPH. The engine was just fine.
Then I realized what had happened. I had leaned the engine for peak
power while still on the ground. That is correct procedure for
normally aspirated engines, but this was a turbocharged
engine. Stupid idiot! With the engine at takeoff power, the turbo
rapidly spooled up, pushing more air into the cylinders. With the turbo up
to full speed, the engine needed a lot more fuel to keep the
mixture in the right range; on the order of 34 GPH...almost full rich. Ambient air pressure has virtually no effect on fuel
flow in turbo equipped aircraft. That's the glory of using a turbo; engine power (and therefore fuel
flow) is not affected by altitude. I was satisfied that the engine burp
was due to operator error. It seemed totally happy now, and I decided to
press on with our flight. Still, I was a bit spooked. The faint
engine roughness on the Addison to Liberal leg wore on my mind; but still, any
roughness there may have been disappeared on the Liberal to Cheyenne leg.
Had the roughness just been my imagination...nerves? Maybe we picked up
some water in the fuel back at Cheyenne. After all, it HAD rained while we
were there. Still, I carefully checked the fuel for water during
preflight; the fuel was pristine and free of contaminates of any kind. No,
it just had to be operator error...I had found my error and corrected it.
The engine was now completely happy, purring like a kitten. There was no
logical reason to turn back to Cheyenne. If I did, what would I do; ask a
mechanic to look at the engine? What would he say? I was pretty sure
he wouldn't find anything wrong. When I told him about my gaff with the
fuel flow, he'd just say, "There's you explanation!" No, it just wasn't
necessary. Still it nagged at me.
The MEA for the trip to Riverton was 12,000 feet. As we left Cheyenne
behind and climbed past 10,000, I started to relax. All was
right with the world. We drifted up to12,000 and everyone was on oxygen.
There! What was that...did the engine just miss a bit there? I
leaned forward and scrutinized the instruments. They were all perfectly
happy. Geez, I tell ya, a guy gets over the mountains and the engine goes
on automatic rough...just like flying over water. It's all in the mind.
I was seeing snakes under every rock. Just calm down! I slumped back
in my seat and tried to look out the window to distract myself.
There...there it was again! I felt it more than heard it; like one
cylinder missing on one power stroke. It could be my imagination, I just
wasn't sure; it was so subtle. It wasn't continuously rough, just a tiny
little burp once every few minutes. I switched the magnetos between left
and right sides, letting them run a minute or so. No difference between
the two; the problem wasn't ignition. So, it had to be fuel or air
related. Was something wrong with the turbo; could it be shedding parts
into the induction manifold? No, no manifold pressure was steady and
normal; oil pressure and temperature were normal. If the turbo were
disintegrating, it would show on the manifold pressure gauge or in the oil
pressure/temperature. Both ignition and air were good. How about
fuel? The fuel flow was right where it should be in cruise climb, 20 GPH.
I checked the EGT for each cylinder. Hmmmm...there was that odd divergence
in temperatures between even and odd cylinders again. They were only off
30-40°C. Is that normal? I didn't know.
This EGT difference didn't seem as pronounced at lower altitudes. Maybe it was
related to the sporadic missing, but I wasn't sure. Maybe one of the
injectors was partially clogged, I don't know. Anyway, it was pretty clear
the engine was mechanically sound, ignition was good, air was good, fuel flow
was good, all gauges in the green. Could it be that little hiccups were
normal at this altitude? Nah. I hadn't felt the hiccup in a few
minutes, maybe it really was my imagination. Maybe my nerves were just
exaggerating the whole thing. Bah...I watched the engine instruments
carefully, but couldn't relax.
Soon,
ATC called recommending a deviation around that big thunderstorm. I had
expected a deviation and would have called them in a few minutes, but they beat
me to the punch. I had been watching the storm on XM RADAR in the plane.
Normally, I would have deviated upwind of the storm, going around the west side.
I wanted to avoid getting downwind of it as hail and turbulence often lurk on
the downwind side. However, that would have put the storm between us and
Casper, WY. I wanted to keep Casper open as a safe harbor, just in case we
needed it; especially with my apparently irrational uncertainty about the engine. I decided to
deviate to the east, giving the storm an extra 10 mile berth for hail insurance. ATC OKed our plan and we were off on the detour.
We flew through the hiss of occasional light rain and a few clouds.
Nothing big. In the distance to the east was a
fabulous rainbow. The rain from the storm was being blown off, drifting
over the top of us, and falling far from the storm. Hmmmm...how about the
hail? I sure didn't want to run into any. For a few minutes, we were
unexpectedly engulfed in a snow shower. Uh oh...could we run into icing
conditions? The outside air temperature was in the mid-thirties and there
was no evidence of ice accumulation. We seemed to have left most of the
precipitation behind us. No, we were in the clear as far as ice was
concerned.
ATC called again asking how much longer it would be before we were able to
get back on V138. The storm was big; I guessed another 10 minutes of
detouring would be necessary. In a grumbling, irritated tone, the
controller told us to contact Casper approach control. We called up Casper
and gave the controller there the story. Apparently ATC had not
coordinated with Casper regarding our flight; not surprising
considering how ticked off the ATC guy sounded. The Casper controller was
very friendly and helpful. He watched us carefully on RADAR and after
about 15 minutes, handed us back to ATC. We were now north of the storm
and rapidly putting it on our tail. We would need to start down soon. ATC monkeyed around handing us off to three different controllers on different
frequencies in the span of less than five minutes. ATC finally cleared us
for descent and we started down.
During the trip, the engine continued its almost imperceptible, sporadic
roughness. As we descended, the roughness became less and less, until at
about 10,000 feet, it disappeared altogether. That's weird. The
engine seemed fine now. Maybe the plugs got fouled when I landed in
Cheyenne with the fuel flow too rich, and the crud just now burned off.
I had little time to consider that as we were rapidly approaching Riverton.
When we had the airport in sight, I cancelled our IFR flight plan.
Overflying the airport at 2000 feet AGL, I couldn't find a wind sock or any
other indication of wind direction. No matter, Riverton AWOS said the wind
was 300° at 25 knots. The wind was strong, but
steady and blowing almost
straight down runway 28. Shouldn't be a problem. I set-up to land on
runway 28. On final approach, I had to hold a significant crab angle.
I figured the wind was just much stronger at pattern altitude and that by the
time I got to the ground, it would slack off. On short final, I
transitioned to a side-slip. It took a lot of bank to hold the extended
runway centerline. I was nearly running out of rudder travel. Still,
the approach was stable and I rode it to touchdown. As the plane rolled
out and started to level itself on the landing gear, the wind pushed us hard
towards the left side of the runway. Full aileron, lots of rudder, and
judicious use of the right brake straightened us out OK, but I was surprised.
We should be landing almost straight into the wind, but this was basically a 90°
crosswind. Man, that AWOS report was way off! They better have that
wind direction sensor checked. I'd estimate the wind at 20-25 knots from
about 350°.
We found the FBO, but had to taxi a long way to
find a tie down. There was no way I was just going to park the plane in
front of the FBO in this wind without a tiedown. We walked to the FBO and
found no one around. I called the after-hours fueling number and a perky
woman answered. She said she'd hop in the car and be right out in ten
minutes. Great. We lounged in lawn chairs until she arrived.
While we were waiting, I called the FSS, got a weather briefing for the Riverton
to Idaho Falls route, planned our flight, and filed an instrument flight plan.
The lady and her daughter showed up, opened the FBO,
fired up the fuel truck, and zipped down to our plane. I accompanied them
to supervise the fueling while Jane and the kids took a break and rummaged
around the FBO. By the time we got back, each kid had a fist full of
candy. We paid up our bill and strolled back to the plane. I
carefully looked over the engine, including shining my flashlight inside the
engine compartment. Absolutely no evidence of any problems. No oil
or fuel leaks, no carbon or soot accumulation, no nothing, if anything it was
excessively shiny and spotless for an airplane engine. Oil looked great;
nice and clean and plenty of it. Absolutely nothing to give the slightest
indication of a problem.
Well sheezh...could I have been imaging the whole
thing after all?
Date |
6/24 |
ATC RADAR Track
(click to enlarge)
|
Leg |
Riverton, WY ®
Idaho Falls, ID |
Route |
V330 |
Duration |
1.6 hours |
Log Comment |
Rugged terrain near Jackson Hole. |
Time to depart for Idaho Falls. Clearly, despite what Riverton AWOS was
reporting, runway 19 was not favored by the winds. It would be better to
use runway 1. The only problem was that runway 1 was 4800 feet long.
With my suspicion aroused about the engine, I would have preferred runway 28
with its 8200 feet of asphalt. If the engine puked on take-off for some
reason, I'd have space to land straight ahead. Well, the terrain was level
and unobstructed, so if it came to it, I should be able to pull off a successful
off-field landing.
We taxied to runway 1 and I did an exhaustive, careful run-up. The engine
was strong, no problem at all. We received our clearance, taxied onto the
runway and took off. The engine purred like a kitten; sweet! I was
very reassured, the engine was happy and so was I. We transitioned to
cruise climb and began our ascent to 14,000 feet, the MEA to Idaho Falls..jpg)
The scenery was spectacular. V330 would take us on an L shaped route,
up to Dunoir VOR, then a dog-leg down to Jackson Hole, before finally routing us
west to Idaho Falls. We paralleled a highway through a valley for some
time, climbing all the way. At 11,000, ATC called us and said they had
finally made RADAR contact. Shortly thereafter, we leveled at 14,000 and
throttled back to 65% power. We loafed along for about 30 minutes when ATC
called and gave us direct to Idaho Falls. Great! That would
save a lot of miles. We turned directly west and marveled at the sun
setting over the rugged mountains.
I looked down and noted several smooth looking meadows on the tops of gently
rounded mountains. They would have made great emergency landing spots.
I'm sure I could get the airplane down safely in one of those meadows if I had
to, but it would be a very cold night indeed. There was still snow in the
shadowed portions of the hills. It was twilight now and in 15 minutes, it
would be getting dark. It would be harder to make a forced landing at
night. The engine seemed OK. It seemed slightly rough, but none of
the sporadic missing encountered on the previous leg.
We dropped into Idaho Falls just as the last faint traces of twilight faded.
Darn, we were only about 3-4 flying hours away from Walla Walla. We were
tired, and it seemed best to stop for the night. If we hadn't been delayed
by that thunderstorm over the airport in Cheyenne, we probably would have made
Walla Walla. Ah well, that's the way it goes flying small airplanes cross
country. You've got to be flexible because the weather is going to throw
you a curve ball once in a while.
I taxied around the packed parking ramp, looking for a place to tie down.
I found a spot, shut down, and pushed the airplane into the slot. No one
was around and no ramp lights were on. We grabbed our overnight bag,
rounded up the kids, and started walking. We had to walk quite a ways to
find a gate. I called a motel in town on my cell phone, and they sent a
van out to get us. They even gave us a special "flight crew" rate on the
room! We ordered pizza, called my parents to update them on our progress,
watched TV, and went to bed.
Date |
6/25 |
ATC RADAR Track
(click to enlarge)
|
Leg |
Idaho Falls, ID ®
Baker City, OR |
Route |
V21 DBS V298 DNJ V121 |
Duration |
2.5 hours |
Log Comment |
Flew at 16K. No way to lean
engine for smooth operation, low alt. OK. |
We slept in late, took a leisurely breakfast, and caught a motel van out to
the airport. It was 9:00 AM and it looked like we'd be off by 10:00.
Our destination was Baker City, Oregon. A moderately long flight with VFR
weather the whole way. I filed for instruments anyway. It was good
to get some practice, but it would also ensure we'd be in contact with ATC in case something
happened. We would need to climb to 16,000 feet to meet MEA requirements,
so I had the FBO top off our oxygen.
After a lot of fiddling around, we were ready to depart. I did a
careful run-up. Everything seemed in order. We taxied onto the
active and took off. We had convoluted routing for the initial part of the trip.
That was due to surrounding mountainous terrain and a profusion of airways and
intersections. Eventually we got established on V121 and things settled
down..jpg)
Climbing past 10,000 we donned oxygen masks. After another few minutes,
we leveled at 16,000. After picking up some speed, I throttled back from
cruise climb power to 65%. The engine did not like it and began running
rough. I powered up and the engine smoothed out. The engine seemed
fussy at lower power levels. I fiddled with the fuel flow and eventually
got it to run fairly well; although it seemed like it was missing occasionally.
It was elusive...at times I would be sure the engine was missing, at others I
would be convinced it was my imagination.
The fuel flow for smooth operation was somewhat higher than called out by the
book. The book said we should be burning 16.9 GPH, but the fuel flow meter
in the cockpit indicated ~21 GPH. I wasn't sure if the meter was off, or
the book was excessively optimistic. Just in case, I calculated our range
using the 21 GPH value. It looked like we would make Baker City with IFR
reserves even if the fuel flow was as high as the meter indicated. An EGT
check indicated a 100°C temperature spread between
even and odd cylinders. That was the largest difference I had yet
encountered on our trip. Is this normal at this altitude? I had only
ever flown this high a couple of times before and didn't experience these problems; but
that was a different airplane. Hmmmm...well, all the engine instruments were in
the green and we were already half-way to Baker City. No point in turning
back. I decided to just kept an eye on the situation. The scenery
was spectacular, but I couldn't relax; a forced landing in this country would be
rough.
Finally, ATC cleared us to descend to Baker City.
As we descended, the engine seemed to run better and better. Finally,
below 12,000 feet, it purred like a kitten. Is this normal? I
honestly had no clue. As we landed in Baker City, the engine was totally
happy.
I taxied up to the fuel pump and shut down.
We got gas and a coke. The kids played in a little park next to the apron.
I pondered what to do. Go on or call back to Addison to see if they
mechanics wanted me to check
the plane? The plane seemed to be running fine now. The leg to
Walla Walla would only take about 45 minutes. We wouldn't be flying high
where the engine seemed fussier.
There were several airports along the way we could stop at, if needed. Aw
heck, I decide to press on; it was probably just a fouled plug or something.
I called my parents and told them when we expected
to arrive.
Date |
6/25 |
ATC RADAR Track
Flew VFR - no RADAR track available.
|
Leg |
Baker City, OR ®
Walla Walla, WA |
Route |
V357 |
Duration |
1.1 hours |
Log Comment |
Engine fine @ 7500'. Flew
VFR. |
We piled into the plane and fired up. I did a very thorough run-up as
had become my custom on this trip. The engine seemed
good. It was pretty hot and I was somewhat concerned about density
altitude, but our take-off was fine and we climbed out well. We were off
for Walla Walla.
I eyed the engine gauges suspiciously. They all behaved themselves and
the engine was strong. Again I doubted myself...was the engine OK or not? I was becoming increasingly convinced something was
amiss, but the engine was in a good mood at the moment.
We crested the Blue Mountain range and descended into the Walla Walla valley.
I made a bee-line for the airport, but had to make a 360°
turn south-east of town to lose some altitude. We landed, and began taxiing to the only FBO on the field.
The tower gave us taxi instructions, but it looked like we were heading off into
the boonies. The tower eventually told us to stop and tie down...we were
right next to the FBO. Hmmmm...didn't look like much; just one little hanger and a
fuel truck.
We piled out and began unloading our gear.
After 20 minutes, my parents showed up and drove us home. I was glad to be
in Walla Walla.
The next day, I pondered the engine issues again.
Overnight I had pretty well convinced myself that something was amiss with the
engine. It just didn't seem reasonable that the engine would be so
extraordinarily fussy about fuel flow at high altitudes. I decided to head
out to the airport and talk to a mechanic. Maybe he could make some sense
out of all this. I jumped in the car and headed to the airport.
I found the head mechanic and described the
symptoms. The main thing was that the engine ran a bit rough at high
altitudes. He immediately suspected the magnetos. When air pressure
decreases, magnetos are more likely to arc internally and mess up the ignition.
The magnetos are supposed to be sealed and pressurized, but seals fail
sometimes. That sounded reasonable to me. Offhandedly, I offered one
more bit of the puzzle...the strange EGT differences between even and odd
cylinders. The difference seemed to increase with altitude. He
stroked his chin a bit and pondered. Could be an air leak in the intake
manifold. Let's pull the cowl and see. Before doing that, I called
Monarch back at Addison and talked to one of their mechanics. I explained
the whole thing and he agreed that we ought to crack the cowling and take a
look.
We pulled the airplane up to the hanger and remove
the cowling. The mechanic leaned over the engine and about 5 seconds later
exclaimed, "Oh, here's your problem!" He held up a loose hose with a big
grin. "It's the upper deck air reference for the left side fuel injection
rail," he began. He proceeded to describe the whole thing and how it could
explain the symptoms I was seeing. He said he was fairly certain the hose
was left disconnected after the last 100 hour inspection, because the clamp was
loose. It was a screw type hose clamp and was just rattling loose on the
hose. There's no way it had been properly tightened to hold the hose in
place. Oooh...that was bad. We called Monarch back and he explained
what he found to the Monarch mechanic. That was an awkward moment.
Aircraft mechanics pride themselves on being meticulous and this was a scorching
indictment. I was just glad that we had the problem solved; I was relieved
that I could have confidence in the airplane again. This episode cost $75,
but it was money well spent!
Date |
6/27 |
ATC RADAR Track
(click to enlarge)
|
Leg |
Walla Walla, WA ®
Coeur d' Alene, ID |
Route |
V444 GEG <direct> |
Duration |
1.3 hours |
Log Comment |
Flew to Coeur d' Alene to see
Janet & Scott Poorman. |
Jane wanted to see an old high school buddy, Janet.
She hadn't seen her in a few years. We piled the whole family
into the plane and zipped up to Coeur d' Alene, Idaho for an all day
visit. We cruised at 7000 feet, overflying occasional wispy
clouds. The engine ran well and gave us no cause for concern.
The jury was still out though, because we weren't really high enough
to see the problem. ATC cleared us direct to Coeur d' Alene when
we were still a good way out from Spokane. That cut a few
minutes off the trip. After landing, we taxied over to the FBO
and shut down. About 20 minutes later, Janet pulled up in her
van to pick us up.
We hung out at the park, went out to lunch, and spent some time
at the new house Janet and Scott were building. The kids got
along famously and both families were instant pals. Scott even
managed to break away from work for a couple of hours. All in
all, enormously entertaining. Jane and I were so glad to have
the airplane. Being able to zip up to Coeur d' Alene in an
hour is what made it all possible. It would have taken us at
least six hours of driving to make the trip by car. |
|
|
The boys hit it off right away.
|
|
|
The motley crew with Janet and Scott's new house in the background.
|
|
|
|
Date |
6/27 |
ATC RADAR Track
(click to enlarge)
|
Leg |
Coeur d' Alene, ID ®
Walla Walla, WA |
Route |
<direct> |
Duration |
1.2 hours |
Log Comment |
Back to Walla Walla. |
|