On one Mag? Temptation and decision

[Terry]

Yesterday was an unusual day here in Ohio for December so I decided to
get my badly needed flying "fix". Clear skies, smooth air and a
planned trip to southern Ohio and back to home base (DLZ). Onboard was
myself PIC and wife. The usual pre-flight and run-up everything normal.
After reaching altitude of 3500 I noticed a very sight roughness in the
engine which was really just more of a "seat of the pants" feeling that
the engine wasn't running as smoothly as it should. I guess that comes
with flying my little Cessna 150 over 600 hours and developing a feeling
how things should feel. After about 15 minutes the engine seemed to
smooth out and everything was fine. I decided not to go over the hilly
terrain in southern Ohio and instead just fly for the sake of flying and
stay closer to home. The engine was running smoothly and we climbed to
5500 to site see and visit some local airports along the way.
Belfontaine Ohio (7I7) has a new airport so we decided we would stop and
visit the new lounge and FBO facilities before heading back to (DLZ)
about 40 miles away. Taxi for takeoff engine running smoothly, run-up
and one mag completely failed. Extreme leaning and usual procedures do
not help and after another run-up, still one mag with no fire. Taxi
airplane to tiedown and contemplate options. I consider myself to be a
very safe pilot with over 1000hrs experience but I must confess that I
did consider several options before picking the right one for me. Please
keep in mind that we were only 40 miles from home airport. I know my
airplane. I'm not perfect and I will always be learning, I try to fly
safe and make good decisions.

Option 1 - Leave the airplane for repairs and take taxi to home base to
pickup car. Very long wait for taxi and pain in the butt. Return trip by
car later for plane pick-up and unknown mechanic working on airplane.

Option 2 - Let my wife take taxi to home base and I fly airplane out on
one mag. I would never have considered her flying with me on one mag!
This gets the airplane to home base and my mechanic that knows the
airplane well.

I chose to leave the airplane there, get the mag replaced and take the
taxi. BUT I cannot overemphasize enough how TEMPTING it was to consider
flying the airplane out on my own and get it repaired at home base
(DLZ). A little voice kept saying "You can make it, You can do it!" go
for it. I can't state strongly enough how strong the urge was to avoid
all the hassle and just fly the airplane home! Yes, I knew if I lost
the other mag I was in for a forced landing. Yes I knew if I did have a
forced landing I might get hurt. A forced landing might have resulted
in bent metal and dismantling the airplane. But that little voice kept
saying "go for it". I know it might be hard to understand, but in a way,
it was harder to NOT to fly the airplane out of there!

I didn't "go for it".... Today is another day. The sun is shining and I
have an airplane sitting 50 miles from home. It will get repaired on
Tuesday. I will have my wife drive me to the airport to pick-up the
airplane. I will pay the repair bill. Then.... I'll just go flying for
awhile....with a big smile on my face!

QUESTION... What would you have done?

[Robert Moore]

Terry > wrote

>QUESTION... What would you have done?

Well...I flew my homebuilt for 10 years with only one
magneto installed, and a Fairbanks-Morse tractor mag
at that. Never missed a beat!

Bob Moore

[Roger Long]

Absolutely, positively, do not fly on one mag if the engine is designed for
two! The second mag is not just for redundancy.

The two spark plugs light off the cylinder charge in two separate places.
Ever heard of burning your candle at both ends? The combustion takes place
faster so the burning is over when the exhaust valve opens and things have
time to cool down a bit. With one mag, the exhaust will be hotter and, in
some cases, combustion still taking place when the exhaust valve opens.
This can burn valves. On some engines, it can even damage the exhaust
piping.

Flying even 40 miles this way could be burning the engine's candle at both
ends and maybe even your own.

--
Roger Long

[Tom Pappano]

Terry wrote:
>
> Option 1 - Leave the airplane for repairs and take taxi to home base to
> pickup car. Very long wait for taxi and pain in the butt. Return trip by
> car later for plane pick-up and unknown mechanic working on airplane.
>
> Option 2 - Let my wife take taxi to home base and I fly airplane out on
> one mag. I would never have considered her flying with me on one mag!
> This gets the airplane to home base and my mechanic that knows the
> airplane well.

Hmmm...

The first thing that popped into my head was the possibility of broken
metal pieces if the magneto gear broke or something. I think I would
want to inspect the mag before running the engine any amount of time
to prevent further damage. Even though it might run ok on one mag,
a stray bit of metal might cause a problem with the remaining mag.
I'm too cheap to take a taxi 50 miles. 8-) I might try to rent a car
locally if the repair could be done quickly. Might be cheaper and
simplify getting back to the plane. I think you did the right thing.

Tom Pappano, PP-ASEL-IA

[Terry]

Roger Long wrote:
Geesh! Thanks Roger, something else to worry about.. :)
Flew for about 1 hour and 40 minutes...don't know when the mag went
out... no engine indication roughness at all.

Terry

> This can burn valves. On some engines, it can even damage the exhaust
> piping.
>
> Flying even 40 miles this way could be burning the engine's candle at both
> ends and maybe even your own.
>
> --
> Roger Long

[EDR]

In article >, Terry
> wrote:

You forgot OPTION 3... call a fellow pilot at the home drome and ask
him/her to come pick you up. This avoids those long taxi rides.
I fly out of OSU and have several pilots I can call on for such help if
I am within several hundred miles/two or three hours of Columbus.

BTW... 7I7 is closed, the identifier for the temporary identifier for
the new airport is 4F5. They have been discussing applying for BRA as
the permanent identifer.

I won't even fly my 65 hp Champ on one mag.
It would have to be very dire straits for me to even consider it with
any dual magneto powered airplane.

[Roger Long]

Well, in fairness, I've got to tell you all this little story.

I took my old CFI, who did most of my primary training for a flight the
other day after not flying with him since before I got my license. Of
course, I really wanted to look good and also show off the airplane I
manage.

I proudly showed him our digital tach and how the red LED's that come on
when either mag is off help keep you from taking off on just one mag. One
mag was a bit rough so I cleared it.

We took off and about 4000 agl, Joe looked over and said, "What's that red
LED on the tach mean?"

No apparent harm done except to my pride. I did notice that RPM was a
little low on roll out but figured it was just the weather.

There's a lot to be said for a sterile cockpit and not yacking away during
run up and take off.

--
Roger Long

[Terry]

I figured more would be familiar with (7I7) then the new (4F5).
Nice airport!

[EDR]

In article >, Terry
> wrote:

> I figured more would be familiar with (7I7) then the new (4F5).
> Nice airport!

Indeed. I am waiting for them to build the restaurant they have been
talking about.

[G.R. Patterson III]

Terry wrote:
>
> QUESTION... What would you have done?

Left the plane and taken the taxi.

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

[G.R. Patterson III]

Roger Long wrote:
>
> No apparent harm done except to my pride. I did notice that RPM was a
> little low on roll out but figured it was just the weather.

We flew into Asheville a few years ago, and the radio died during the approach.
They gave me a green light, but I was faced with handling the departure NORDO the
next day.

I called the tower and got instructions, taxied down, did my runup, got the green,
and took off. She didn't feel right climbing out, but I figured it was just the
mountains. She still didn't feel right in cruise either, though. I was into my
second panel check and considering landing at a nearby airport when I noticed I
was running on one mag. The distraction of dealing with the light gun and traffic
that I couldn't hear was enough to cause me to fail to cut the switch back all
the way to both during the runup.

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

[David Johnson]

Another option would be to ask around the airport you are stranded at
to see if you can find a ride to or near your home base.

A few years ago I was doing some aerial exploration about 50nm
from home base with my daughter on board. Suddenly something
smelled hot. There was no apparent change in engine or electrical
function, and no smoke - but something was obviously amiss. So I
headed for the nearest airport and landed. An inspection revealed
a hole in the left exhaust collector - and scorched paint on the
cowling (source of the smell). No question but what the plane was
unairworthy. Since repairs would require ordering parts (and it was
a weekend to boot), I secured the plane and headed over to the office
to inquire about possibilities. When I did so a woman standing nearby
said "My husband could have taken you - but he just took off" Bummer.

Then she said "Tell you what - I have plenty of time - I'll drive you
to your home airport". And so it was. About an hour's drive each way -
and she wouldn't accept any payment. There are still good Samaritans
out there!

I later had the plane repaired where it sat, then bummed a ride with
a co-worker (who was passing through that town on a field trip) to
go and retrieve it.

[John Harlow]

> Option 1 - Leave the airplane for repairs and take taxi to home base
> to pickup car.

Reasonable assurance of outcome....

> Option 2 - Let my wife take taxi to home base and I fly airplane out
> on one mag.

Questionable outcome......

> QUESTION... What would you have done?

Fix the aircraft before flying it again.

[Roger Halstead]

On Sun, 28 Dec 2003 19:14:30 GMT, "Roger Long"
m> wrote:

>Absolutely, positively, do not fly on one mag if the engine is designed for
>two! The second mag is not just for redundancy.
>
>The two spark plugs light off the cylinder charge in two separate places.
>Ever heard of burning your candle at both ends? The combustion takes place
>faster so the burning is over when the exhaust valve opens and things have
>time to cool down a bit. With one mag, the exhaust will be hotter and, in
>some cases, combustion still taking place when the exhaust valve opens.
>This can burn valves. On some engines, it can even damage the exhaust
>piping.
>

I would think with incomplete combustion it would be cooler in the
cylinder and hotter in the exhaust stacks.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair?)
www.rogerhalstead.com

>Flying even 40 miles this way could be burning the engine's candle at both
>ends and maybe even your own.

[Peter Duniho]

"Terry" > wrote in message
...
> QUESTION... What would you have done?

Having been in this position myself, I can tell you what I would have done.
I left the plane at the airport and had it fixed there.

I agree with your decision. Wouldn't you look silly if that remaining
magneto failed on your way home after you'd found one had failed? Would you
feel silly if you'd had a less-than-perfect off-airport landing and died,
just because you didn't want to be bothered with the hassle of leaving the
plane?

You are right, it's tempting to do the wrong thing. That's true in a LOT of
situations, and not just while flying. But there's great satisfaction to be
had in resisting the temptation and doing the RIGHT thing. I'm sure you
know this by now. :)

Pete

[Ron Natalie]

"David Johnson" > wrote in message om...
> Another option would be to ask around the airport you are stranded at
> to see if you can find a ride to or near your home base.
>
Yep, after our bouts with ignition problems we were heading over the bay one day
and she started misfiring. Sure enough, one mag was completely messed up. We
brought her into the nearest airport, and it only took a few minutes of asking around
until we found some guy in a Maule who was willing to fly us home. Amusingly, after
he agreed to do this it turns out he had been at one of the rec.aviation parties at our
house (he was the flight instructor of one of the crowd and they stopped off at our
place in the middle of his instrument XC).

[John Galban]

Roger Halstead > wrote in message >...
> On Sun, 28 Dec 2003 19:14:30 GMT, "Roger Long"
> m> wrote:
>
> >Absolutely, positively, do not fly on one mag if the engine is designed for
> >two! The second mag is not just for redundancy.
> >
> >The two spark plugs light off the cylinder charge in two separate places.
> >Ever heard of burning your candle at both ends? The combustion takes place
> >faster so the burning is over when the exhaust valve opens and things have
> >time to cool down a bit. With one mag, the exhaust will be hotter and, in
> >some cases, combustion still taking place when the exhaust valve opens.
> >This can burn valves. On some engines, it can even damage the exhaust
> >piping.
> >
>
> I would think with incomplete combustion it would be cooler in the
> cylinder and hotter in the exhaust stacks.

And it's not that much hotter in the exhaust stacks either. On a
single mag, I usually see my EGT rise about 50 degrees. Unless you're
leaning hard and making lots of power, I wouldn't worry too much about
running on one mag.

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