On one Mag? Temptation and decision

I'm with you Paul, as far as saying the answer is not 100% clear. The
monday morning quarterbacks have all the easy answers. Mechanical troubles
away from home can create real dilemmas.

If it's only 40 miles, VFR, and there's an interstate highway to follow, I
might do it if there was some disastrous consequence to not making it back
on time. A 150 can be landed almost anywhere, even in an empty Wal Mart
parking lot. But the original poster's own mechanic could also easily drive
over with a new mag for not much additional expense, or the local mechanic
could easily put one in or troubleshoot the bad one. I've had mag troubles
away from my home field a couple times, and it's always been easily and
quickly fixed. One time, it was that the points were burned after the
capacitor wire had severed, and new points and a capacitor were all that
were needed and on hand at the shop. A one hour delay.

"Paul Mennen" wrote in message
m...
I would have also left the plane.
No reason to kill yourself over a minor inconvenience.

More than inconvenience. A dead mag means the airplane is not legally
airworthy, and flying it that way presents a whole range of threats,
from a second mag failure through to insurance invalidation and to the
loss of your license.

Ok, I'm setting myself to get totally jumped on, but hey this
thread is far too one sided to make a legitimate newsgroup thread.
So I feel compelled to offer another perspective.

First with regard to the "loss of your license" comment above,
If you crashed as a result of your second magneto failing, I doubt
you would admit to the FAA inspector or your insurance agent that
the first mag failed before takeoff. (After all, if the first mag
just failed on the previous flight, it would be just about as likely
that it failed after takeoff of the flight in question.)

Second, I think the "kill yourself" comment above is overly dramatic.
You were trained what to do when an engine fails weren't you? And
you do practice this I assume when you enter a traffic pattern that
is totally devoid of other traffic or other complications prohibiting
a power off landing? I've actually had to land without power once
thru no fault of my own. It was even in Colorado, not exactly the
most hospitable terrain in the country for forced landings, yet my
plane and its occupants were just fine. If I was unlucky enough my
plane would have been damaged, even totaled perhaps, yet I believe
I could walk away from such an incident no matter when the engine
decided to give up the ghost. (At night, my confidence is that would
be dramatically reduced.)

This little bit of flying bravado doesn't mean I seek out the situations
demanding such skill. (The old expression about the superior pilot
comes to mind. In fact the failed mag thing happened to me once.
I had the whole family loaded up ready to fly to Tahoe. During the
run-up, one mag was completely dead. For one, I was planning on flying
over some pretty rugged mountains. And then their would have been the
same problem on the return. Also I had a perfectly functional car parked
right there at the airport (although it did take us about 5 times
longer to drive). However in other circumstances I might do it.
For instance if I had to make it only 40 miles back to home base, and
the terrain in between was hospitable, and the wx was good vfr, and
of course it was daytime. I would take extra precautions - such as
circling the field while climbing to give me an early out. I would
try to choose a route and fly high enough to remain within gliding
distance of an airport for as much of the flight as possible. (Actually
after my return from Tahoe, I had no hesitation about flying it to
my mechanics airport. It was only 15 miles away with two large
airports directly enroute.)

One has to be careful about the "no reason to take unnecessary risks"
idea espoused by posters in this thread. The rub is in defining
unnecessary. Some of my non-flying friends question my sanity for
taking unnecessary risks for going out airport hopping on a perfectly
fine windless CAVU day just after my most experienced and nitpicky
mechanic has gone over everything with a fine tooth comb and pronounced
the plane airworthy. Some of my heavy metal flying friends question
my sanity for packing my family across the Sierras and the Rockies
in an airplane with only one engine. And then when I mention that I
also fly at night and in IFR wx, they say "with only one pilot, only
one alternator, only one vacuum source, no anti-ice equipment, what
are you nuts?" No I'm not nuts. Thousands of other pilots do it also.
Its all what you are used to and how you balance the risks and the
rewards. I always say that a pilot has to have the right mix of
desire and fear. Not enough desire and too much fear and the pilot
will not get experience because he will never go anywhere. Not enough
fear and too much desire and he will not get experienced either since
he will kill himself first.

So to all those "certainly leave it on the ground" responders,
don't you occasionally go biking even if those brakes are a
little bit worn. And surely an errant truck driver could wipe you
off the road with barely a 1 second mistake. And what about those
pilots of the 1920's. Are you saying if you were born say a
century ago, you wouldn't have been among that fun loving
pilot crowd. If I remember right, they only had one magneto
even when everything was working. Heck I don't think they even
had the luxury of a throttle. (Of course their engines failed
so often, for so many different reasons, that the extra safety
from having two magnetos would have been insignificant
My point is we all take risks. We just have to evaluate each
one as objectively as possible taking in all the statistics we
know and the relative rewards for taking the risk.

And saying "and it's against the FARs" is a cop out too.
I feel that the FARs are pretty much irrelevant in the decision
making process. Certainly one should ponder why the FAA made this
decision, yet as I tried to point out, everyone's risk/reward system
is different. There are many things the FARs allow me to do that I
will not. (One of many examples is that I'm allowed to take off in
zero-zero conditions, which I feel is not worth the risk. Some fellow
pilots will do this, but I do not denigrate their decision, since
their piloting skills are different as well as their risk perceptions.)
There are other things prohibited by the FARs that I feel perfectly
comfortable with. I've taken off many times with equipment not working
that was required by the type certificate (even the airspeed indicator
once). Before I get the flood of irate responses from those of you
who claim that you always fly legally, let me point out that FAA
inspectors claim they can find something illegal with every aircraft
if they look closely enough, and usually they don't have to look very
close. I just hope too many FAA inspectors are not reading this
newsgroup

~Paul

"Dan Thompson" wrote in message m...
I've had mag troubles
away from my home field a couple times, and it's always been easily and
quickly fixed. One time, it was that the points were burned after the
capacitor wire had severed, and new points and a capacitor were all that
were needed and on hand at the shop. A one hour delay.

It failed because the capacitor wire broke, not because the
points burned. There's a widespread misconception that the capacitor's
only job is to prevent arcing at the points, but the mag will not
spark at all if the capacitor is removed from the circuit.
The capacitor's job is to intensify the secondary coil's output by
speeding up the collapse of the magnetic field, and it does this by
absorbing the bit of current that would otherwise arc across the
points. Such arcing not only burns those points but also represents
continuing current flow in the primary, just when we want an abrupt
arresting of that flow to collapse the field. The capacitor absorbs
current just long enough that the points can open far enough to
prevent arcing after the capacitor is full.
Of all the concepts that I teach in aircraft systems, the
magneto is the one that students have the most difficulty
understanding.

Dan

"Paul Mennen" wrote in message om...
I would have also left the plane.
No reason to kill yourself over a minor inconvenience.

More than inconvenience. A dead mag means the airplane is not legally
airworthy, and flying it that way presents a whole range of threats,
from a second mag failure through to insurance invalidation and to the
loss of your license.

Ok, I'm setting myself to get totally jumped on, but hey this
thread is far too one sided to make a legitimate newsgroup thread.
So I feel compelled to offer another perspective.

I appreciate your alternative perspective, but if I don't have two
mags, and I know that to be a fact, I ain't flying. It's just not
worth it.

I was talking to a friend recently who lost a mag on take off in a
C-172. He was amazed at how much power he lost. He barely cleared the
trees at the end of the runway and he felt sure that he was going to
have to set down in the parking lot of the local community college
which was about 3/4 mile straight ahead. He was able to get the plane
to about 900 feet, but no more, so he was able to nurse it back to a
landing. This guy is a very accomplished pilot (instrument,
commercial) and it scared him. Freaked me a bit too because the plane
is the plane that I rent most often. When he found out it was a lead
wire that fell onto the block, effectively grounding out the mag, he
was amazed. He was sure that it was something much more severe because
it hampered his climb performance so much.

Lots of times, you need 100% power to take off and climb, especially
if you have obstacles, it's hot and high, etc. Think about it, would
you ever take off with the throttle partially closed? You know, just
for kicks? That's similar to what it's like to take off with a failed
mag.

-Trent
PP-ASEL

On 5 Jan 2004 10:55:53 -0800, (Trent Moorehead)
wrote:

snip

Lots of times, you need 100% power to take off and climb, especially
if you have obstacles, it's hot and high, etc. Think about it, would
you ever take off with the throttle partially closed? You know, just
for kicks? That's similar to what it's like to take off with a failed
mag.

Depending on the density altitude, pulling the mixture back from 1/4
to 1/2 of its total travel would have restored a lot of the "lost"
power. If you fly routinely out of hot-and-high places, this is
standard procedure with two functioning magnetos.

I am by no means suggesting that this should be attempted while trying
to stabilize the aircraft (as in engine croaking on TO), but is
something that I would have done while returning to the field, after
switching mags and determining that one had "died".

You could bet your sweet bippy that I would have done it if I couldn't
maintain altitude/airspeed while returning, while planning for a
forced landing.

Before I was a "pilot", I got a ride in a Taylor J2 with 40 horsepower
(on a good day) and single ignition (one magneto)..

Depending on the situation, I would possibly fly a ferry hop on one
mag, but I would never presume to criticize anyone that would not.

TC

On 28-Dec-2003, Terry wrote:

QUESTION... What would you have done?


Here's a little "hangar flying" story relating to this topic which you might
find interesting.

Last February my wife and I were flying from Newport, Oregon (ONP) to our
home base in Everett, Washington (PAE). The weather was truly crappy, but
freezing levels were high enough to allow for a safe hour plus 40 IFR
flight. About 20 minutes into the flight I happened to notice that one of
the fuel caps on the Arrow was off at an angle, indicating that it was not
firmly secured. In fact, it looked like it might fly off any second. While
cursing myself for being careless on my pre-flight inspection, I realized
that this really was not an emergency. Even if the cap flew off and I lost
all of the fuel in that tank I had more than enough in the other tank to
complete the flight safely. On the other hand, those caps are expensive and
I did not relish the idea of flying along spewing fuel over the countryside,
so I decided to land at Hillsboro (HIO) which was nearly below us at the
time.

Weather on the approach was very wet and bumpy, but the ceiling was at
around 1000 feet, making for an easy ILS. After landing I asked ground
control to just let me shut down off the taxiway for a few minutes while I
got out to secure the gas cap -- turns out it was on tight enough that it
would have remained aboard anyway -- and use my cellphone to call in a new
IFR flight plan for the remainder of our flight home. All told I we were
probably parked for maybe 10 minutes before we got the new clearance and
fired up for takeoff. Now, having just flown the plane with everything
(except the gas cap) seemingly in good order, I was tempted to forego the
runup, but then I considered the weather conditions (pouring rain, strictly
IFR) and reached for the checklist. Of course, when I checked the left mag
the engine missed badly. Probably a fouled plug. However, no amount of
jockeying of throttle and mixture was effective at clearing things up. So I
taxied to "Hangar 53", one of the maintenance FBOs at HIO. The folks there
could not have been more helpful. They dropped what they were doing, pulled
our Arrow in out of the rain, and went to work. Unfortunately, after an
hour or so, they concluded that the problem was in the mag. They did not
have a replacement available, so I was stuck. We ended up renting a car for
the 3.5 hour drive home.

Was I tempted to take off with one sick mag for the flight home of a little
over an hour? NO WAY! The crappy weather was enough of a worry. I THINK I
would have been disciplined enough to say NO even if the weather had been
CAVU, even with my wife protesting that the plane was flying just fine
minutes ago. What's really interesting is that the left mag failed in
flight (it was working fine during the runup before takeoff at ONP) and I
would not have known about it if I hadn't decided to land because of the
fuel cap. If I had instead continued, and the right mag failed while IFR,
the gas cap would have become the least of my worries.

--
-Elliott Drucker