MAYDAY in the Everglades

I'm extremely impressed with the response I've gotten to this post. I know
as a given fact that I will not get hurt in a general aviation aircraft that
I'm flying during daylight hours. It's just a fact that comes with a great
respect for the unexpected (I have a healthy fear of what I don't know). I'm
a pre-flight nut case. I sump the fuel always, even after a 10 minute stop
without re-fueling. The plane has an almost zero time status (now at 125
hours since major OH). I'd had an oil change a couple of days earlier and
wondered if my mechanic had nicked the fuel line, or in some odd manner made
a change to the fuel system, but that didn't and still doesn't make sense.

Regarding my flight plan- I have been tossed out of Miami's Bravo airspace
about as often as girls turned me down when I was a teenager. Not being shy,
that's a lot. The only choice is over the ocean below 3,000, over MIA's
airspace at 7,000 or the swamp to the west. I take the swamp because it's
quiet (except for a few minutes when the big jets are turning final while
West of MIA). At all times I check to make certain I have enough altitude
(except when climbing out, of course), to make solid ground. This time I
knew I could make the interstate, but would truly choose this as a last
resort. The NTSB would get involved, and I'd have to get the plane trucked
out of the everglades. To save my wife and I, I would do this in a
heartbeat. My preference, of course, would be to put down at an airfield,
which I did.

Someone asked me what I'd do differently, and my wife and I have discussed
this several times since Friday. The answer comes up every time - Nothing. I
did and would still do exactly as before, but probably swap the first thing
= full rich to first thing = carb heat. Other than that, no other change. I
didn't touch the mags for concern I'd kill the engine. A dead mag will rob
you of power, but it won't cause a rough sputter. I've been trained to make
as little change to a failing engine as possible. Even an aiplane that's
lost it's oil will continue to fly a lot longer if you don't touch the
throttle or mixture. It's when you make a change that an opportunity to
seize occurs. I did, however, push and poke everything else (or what litter
there is to push in a C152).

My wife who's not a pilot, but spends a lot of time in the right seat
telling me where to go, concluded carb ice. She did this when we first
touched down at Dade-Collier airport. My mechanic on the phone explained
that a bad cylinder wouldn't fix itself, but water in the tanks would
eventually blow through the system. The mechanic I met on the ramp also said
bad fuel. My buddy and CFI back in Lantana (I called everyone), said bad
gas. My wife insisted carb ice.

So whadayall' say. Should I give my pilots license to Lynda or what?

Marty

Marty from Florida wrote:

I didn't touch the mags for concern I'd kill the engine.

I agree with you completely. Switching to one mag would help only in a situation
in which a mag has jumped time. Your description of the symptoms doesn't match
what happens when a mag's mistimed (backfiring usually comes into the picture in
this case). I would not have touched the ignition switch.

George Patterson
There's plenty of room for all of God's creatures. Right next to the
mashed potatoes.

Did you try aggressively leaning while having full carb heat? Possibly
your engine was flooding out from an iced carb venturi. You mentioned
going to full rich, but if it is an icing situation, it may instead
require further leaning with carb heat on and full throttle to get
enough heat in the exhaust system to melt the intake ice. It won't
necessarily melt out right away either, and I assume you had carb heat
on for enough time to clear out any ice It might take say 15 seconds
minimum. When the ice melts, the engine will go rough again until you
set things richer.

Another remote possibility is a valve sticking open. Usually that
happens on startup, and I have never experienced it. That engine has
some history of having sticking problems. You were not that far from
the last major and I assume the oil was reasonably clean so that might
rule that possibility out. Q - was it one cylinder missing (i. e. a
stuck valve) or was it a general engine malaise (mixture problems)?

Mixture and ice problems are why I really like having an EGT to cross
check the combustion and the energy extraction process.

Actually a 4 cyl engine running on three cylinders for whatever reason
will only generate about 50% power and will feel very rough. However,
it can still extend your glide a long long way.

Congrats on making it down OK. The first engine failure is the worst.
Next time won't seem so bad.........!

"nrp" writes:

Did you try aggressively leaning while having full carb heat? Possibly
your engine was flooding out from an iced carb venturi. You mentioned
going to full rich, but if it is an icing situation, it may instead
require further leaning ....


I was going to ask about that. A lean engine runs hotter than a rich
one. But that's mostly EGT, and I'm not sure it will work back
enough to alter the carb temp. What say you folks?

--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

David Lesher wrote:

I was going to ask about that. A lean engine runs hotter than a rich
one. But that's mostly EGT, and I'm not sure it will work back
enough to alter the carb temp. What say you folks?

On the Maule I had, the carb heat comes from a muff on one of the exhaust pipes,
so higher EGTs should produce more heat.

George Patterson
There's plenty of room for all of God's creatures. Right next to the
mashed potatoes.

George Patterson wrote:
Marty from Florida wrote:

I didn't touch the mags for concern I'd kill the engine.

I agree with you completely. Switching to one mag would help only in
a situation
in which a mag has jumped time. Your description of the symptoms
doesn't match
what happens when a mag's mistimed (backfiring usually comes into the
picture in
this case). I would not have touched the ignition switch.

I've had instances of mag failure where switching to one improved the
situation quite a bit. One was a bad timing gear that did include the
backfiring, but another was a shorting distributer block that made the
engine extremely rough and caused a power loss. In that case, I
switched to the good mag and had a much less worriesome ride home.

I guess I don't completely understand your (or Marty's) reluctance to
at least check the mags in flight. Even at best glide, the engine is
not going to come to a stop because you grounded a mag. If it gets
worse, you just switch back, then try the other one. At some point,
you decide which combo (left, right, or both) works best and you leave
it there.

Maybe there is something I haven't considered. If so, I would
welcome enlightenment.

John Galban=====N4BQ (PA28-180)

wrote:

I guess I don't completely understand your (or Marty's) reluctance to
at least check the mags in flight.

On a Lycoming, each mag controls half the plugs on the top and half on the
bottom. There are a variety of problems that will lead to fouling of the lower
plugs. If I start switching mags on an iced up engine, there's a good chance it
will die. There's also a pretty good chance that it won't restart when I switch
back to both. Especially on a carburetted engine, you run a big risk of flooding
the engine while it's windmilling. As long as the engine's running, I won't take
a chance on switching mags. It's just something I'm not prepared to do.

George Patterson
There's plenty of room for all of God's creatures. Right next to the
mashed potatoes.

wrote:

snip

I've had instances of mag failure where switching to one improved the
situation quite a bit. One was a bad timing gear that did include the
backfiring, but another was a shorting distributer block that made the
engine extremely rough and caused a power loss. In that case, I
switched to the good mag and had a much less worriesome ride home.

I guess I don't completely understand your (or Marty's) reluctance to
at least check the mags in flight. Even at best glide, the engine is
not going to come to a stop because you grounded a mag. If it gets
worse, you just switch back, then try the other one. At some point,
you decide which combo (left, right, or both) works best and you leave
it there.

Maybe there is something I haven't considered. If so, I would
welcome enlightenment.

John Galban=====N4BQ (PA28-180)


Years ago I was flying a C-150 and it started running real rough. I did
an airborne mag check and found it ran better on one mag. I flew the
remainder of the trip (about 40 minutes) that way and reported this to
the FBO. Can't remember now what the problem was.
--
Regards, Ross
C-172F 180HP

"Marty from Florida" marty@-x-x-x- remove -x-x- worth.net writes:

[...] I know as a given fact that I will not get hurt in a general
aviation aircraft that I'm flying during daylight hours. It's just a
fact that comes with a great respect for the unexpected (I have a
healthy fear of what I don't know). [..]

I hate to say this, but all that respect and pre-flight attention is
just not a guarantee that you won't be hurt. There are unfortunately
many ways to get hurt in an airplane, some foreseeable, some
preventable, and some neither. I don't want to scare you by dreaming
up scenario after scenario, but rest assured that they exist.

- FChE

Frank Ch. Eigler wrote:
"Marty from Florida" marty@-x-x-x- remove -x-x- worth.net writes:

[...] I know as a given fact that I will not get hurt in a general
aviation aircraft that I'm flying during daylight hours. It's just
a
fact that comes with a great respect for the unexpected (I have a
healthy fear of what I don't know). [..]

I hate to say this, but all that respect and pre-flight attention is
just not a guarantee that you won't be hurt. There are unfortunately
many ways to get hurt in an airplane, some foreseeable, some
preventable, and some neither. I don't want to scare you by dreaming
up scenario after scenario, but rest assured that they exist.


I've definitely gotta agree with that one. If you know it is a fact
that you won't be hurt in an aircraft that you're flying day VFR, then,
with all due respect, you are deluding yourself. Of course, you
probably won't be convinced of that until it actually happens (been
there, done that, still have the blood soaked T-shirt). A great
respect for the unexpected will not guarantee that the unexpected will
not happen. Not by a long shot.

John Galban=====N4BQ (PA28-180)