Oil on the windshield. What would you do?

Here's a question that anyone with a single
engine, constant speed prop might have to
deal with sometime.

You're cruising along happily when suddenly
oil drops start appearing on the windshield. There
is no "bang" or anything else to indicate catastrophic
failure. The nearest airport is out of gliding range.
What do you do?

I'd assume symptoms were caused by some prop seal
failure. I'd go to fine pitch (to minimize further oil
loss) & then reduce RPM to where I could still maintain
altitude (to further minimize oil loss, and to minimize
structural damage if the prop were about to disintegrate)
while heading for the nearest airport.

Can anyone think of a better response?

On Jan 27, 8:28 am, "Tony Cox" wrote:
I'd assume symptoms were caused by some prop seal
failure. I'd go to fine pitch (to minimize further oil
loss) & then reduce RPM to where I could still maintain
altitude (to further minimize oil loss, and to minimize
structural damage if the prop were about to disintegrate)
while heading for the nearest airport.

I'd probably avoid touching anything and head towards the airport.
Could a prop seal really leak enough oil to make drops appear on the
windscreen? Usually prop seal leaks show up as moisture under the
prop.

-Robert, CFII

On Jan 27, 9:01 am, "Robert M. Gary" wrote:
On Jan 27, 8:28 am, "Tony Cox" wrote:

Could a prop seal really leak enough oil to make drops appear on the
windscreen? Usually prop seal leaks show up as moisture under the
prop.

As it happens, this is what happened to a friend of mine
yesterday (although on approach, not in cruise) and we were
debating what might be the proper response had an airport
not been within easy reach. The oil was more like filthy black
streaks, rather than "drops". Still, it was obvious what it was.

Robert M. Gary wrote:


I'd probably avoid touching anything and head towards the airport.
Could a prop seal really leak enough oil to make drops appear on the
windscreen? Usually prop seal leaks show up as moisture under the
prop.


If the engine is running a prop seal will most definitely throw
oil on the windshield. I can related two different props. In
the case of the old Hartzell bladder controllable props (like
many 50's era Navions, Bonanazas, Commanches) the bladder will
start to fail and throw a small amount of oil. It does this
right before you get around to replacing that bladder (it's
supposed to be replaced every three years, but I usually did
it every other year).

Back years ago one of my professors from college was restoring
a Taylorcraft. A bunch of us aviation minded folk headed out
to the airport with him. Two guys got assigned to hold the
tail and I was inside the cockpit on the throttle and switches
while the prof swung the prop. Right after the engine start
and in the seconds before I got it shutdown the prop seal
blew. The prof was fine as he was in front of the prop.
I was OK because I was inside the aircraft...but the two
guys holding the tail got nicely greased.

"Robert M. Gary" wrote in message
oups.com...

... I'd probably avoid touching anything and head towards the airport.
Could a prop seal really leak enough oil to make drops appear on the
windscreen? Usually prop seal leaks show up as moisture under the
prop.

-Robert, CFII


A blown seal (just about anywhere) can result in oil on the windscreen. My
brother blew an oil pressure sending unit that is under the cowl and ended
up with the greasy windshield syndrome (T-18).
If there is an airport within gliding range, sure, pull back the power - it
might save you an overhaul. I wouldn't shut down the engine unless you have
a glider rating and are skilled at real life dead stick landings. Otherwise,
just point towards the nearest airport - no need to panic. Depending on what
kind of seal blew out, it can take a few minutes to actually pump all the
oil overboard. And, even without any measurable oil pressure an engine will
keep running for five to fifteen minutes. Easing off a bit on the power can
help it last longer. The big problem is going to be making the approach and
landing with an oil covered windshield. If you are accumulating a lot of oil
on the windscreen you won't be able to see out - this is a real problem for
an off field landing where you won't be able to see obstructions like wires.


--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

Robert M. Gary wrote:

On Jan 27, 8:28 am, "Tony Cox" wrote:

I'd assume symptoms were caused by some prop seal
failure. I'd go to fine pitch (to minimize further oil
loss) & then reduce RPM to where I could still maintain
altitude (to further minimize oil loss, and to minimize
structural damage if the prop were about to disintegrate)
while heading for the nearest airport.


I'd probably avoid touching anything and head towards the airport.
Could a prop seal really leak enough oil to make drops appear on the
windscreen? Usually prop seal leaks show up as moisture under the
prop.

-Robert, CFII

We used to have an old diaphragm prop. I invited my teaching attendant
to go flying with us (in his younger years he flew P-51's and then flew
for Phillipine air). About halfway home the diaphragm started to go and
I mentioned it to Ron in the backseat as a way to make sure Jim (flying
in the right seat) didn't get concerned. It took him about 10 seconds
to transition to the instruments (it threw a bunch of oil on the right
side, but the left was ok).

Margy

On Sat, 27 Jan 2007 08:28:13 -0800, in
. com, Tony Cox wrote:
Can anyone think of a better response?

Get out your bottle of windex and paper towels, pull back the canopy, and
clean the windshield?

That is just a stupid response and you know it... You should declare an
emergency and pull the ballistic parachute... :-)




Grumman-581 wrote:
On Sat, 27 Jan 2007 08:28:13 -0800, in
. com, Tony Cox wrote:

Can anyone think of a better response?


Get out your bottle of windex and paper towels, pull back the canopy, and
clean the windshield?

On Sat, 27 Jan 2007 12:47:44 -0500, in
, Jon Kraus wrote:
That is just a stupid response and you know it... You should declare an
emergency and pull the ballistic parachute... :-)

Awh 'ell, I've got a canopy, so obviously all I need to do is just pull
the ejection seat firing handle... grin

Grumman-581 wrote:
On Sat, 27 Jan 2007 08:28:13 -0800, in
. com, Tony Cox wrote:
Can anyone think of a better response?
Get out your bottle of windex and paper towels, pull back the canopy, and
clean the windshield?

Do what John Belushi did in the Blues Brothers, take out the napkins,
lean out the window and clean the passenger side window.

"Tower. This is Cessna N12345. We're in a field."

Gerald