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Daaaaaaaaaamn!
Why you need to really look closely at things
during the annual inspection and not accept a "pencil whipped" annual!
Does it Smell Like Gas In Here
Pictured below is a fuel line found on a 1980 V35B----plane kept dying on
take off.
Pilot had been smelling fuel in the cabin for awhile.----guy ended up landing
it with the gear up-----Plane is being fixed by Glenn Biggs---guy told Glenn to
sell it--never getting in a plane again-owner is/was a airline pilot!
(Contributed by Kevin O.)
Here is another in cockpit fuel line that was buried behind the panel when Dave
B. was doing a Speed Slope Windshield. The aluminum was riding against the steel
wire in the defroster duct hose. The pilot's wife was complaining about the fuel
smell! DUH!
Let's Stop Drill The Spar Carry Through
Section
Pictured below is a Baron 58 carry through spar section. The picture on the
left with the stop drill is the front. Picture on the right is the back of the
spar on the lower left side.
Glenn Biggs is putting the Beech Spar Repair Kit on it! (Contributed by Kevin
O.)
Engine Corrosion
aka: I'm "Saving" My Engine
Here's one of the biggest reasons you need to fly your
plane/engine more than 450 hours in six years - Corrosion!
Aircraft and factory reman engine were based all it's life in
San Antonio, TX (KSAT).
Here's the rust evidence:
High humidity and inactivity very likely contributed to this
engine's very early demise. What a waste! Be a CSOB by flying your plane more
often and not letting corrosion be a possible outcome for your very expensive
engine.
Pirep and pics courtesy of Aerobatic Bo owner Chuck G.
Bolt Too Long - Easy Fix (NOT!)
Here is a real gem - for an engine control cable attachment found by Stuart S.
Here is a picture, contributed by Kent F., of a standby vacuum
system cable that was nearly sawed in half by the elevator cable!
I hope the elevator cable is OK!
Battery to Alternator
Wire Chaffing
Can You Say:
"Complete Electrical Failure in Flight?"
Bonanza owner John B. reports the
following:
The engine gages were rebooting occasionally, the
EDM700 and FS450 as well as the P1000 tachometer would shut down and start back
up - with the attendant self-check - as if the battery master had been flicked
off and back on. Worse, it happened with no rhyme nor reason and last time out,
the avionics stack rebooted too and thus, the MX20 rebooted as well. Confounded,
I sought advice and set out to find the cause with instructions largely
consisting of looking for bad connections, or grounds.
Imagine my surprise at finding the fat wire
coming off the alternator, which goes through the firewall on it's way to the
battery master, grounding against a piece of sheet bracket for the baffles!
Worse, each time it arced it was eating away a bit of the bracket - eventually
perhaps even being enough to self-correct as it created clearance - picture
attached.
Was it the fault of the shop, which performed the
annual? Absolutely not!
However, the issue 'does' arise from being in a
shop, giving credence to the old saw. You see, the very first day I owned her I
found the terminal where that wire attached to the alternator was improperly
crimped 'and' the wire was too short to permit properly adjusting the drive belt
tension. So the mechanic in Dear Valley (Phoenix) simply spliced in a section of
wire (to make it longer) and crimped everything properly. End of story, right?
Not quite because in retrospect he also should have added an Adel clamp for
support.
Fortunately, dressing the bracket (along with a
dab of paint), plus once again splicing in a piece of wire (and this time
supporting it with an Adel clamp), will put things right.
Moral of the story? Don't be too quick to assign
blame. Lesson learned?
Eyeball all wires to ensure they're properly
tied-off or supported and NOT rubbing on other things!
Geared Alternator
Failure Trashes TN IO-550 Engine
Can You Say:
"What the Hell Happened Here?"
Be sure your mechanic follows this
SB from TCM regarding the
installation of the alternator coupling assembly!
Here is another geared alternator service letter
from Hartzell:
A-140
Bonanza owner Jim H. reports the
following in the Beech Talk
thread
HERE:
"First of all, as you know, I was very pleased with my new
Bill Cunningham engine. Everything was good...except...about 3 months ago, the
alternator failed flying into ABI. I have a backup and the airport was close, so
I charlie miked and had them look at the alternator. It had failed electrically,
so they replaced it. I flew home happy as clams.
Until I got about 10 miles out of Montgomery...and it failed again. The guys at
Montgomery aviation fixed it...and again, it was an electrical failure. The guys
at Abililene aero stood behind it and everything was all good. The newest
alternator was installed on August 10.
Worked great for 17 hours (foreshadowing) and as I was flying toward
Jacksonville to watch a football game it failed again. Oh, pooh, I thought.
Considered continuing...hell, I did have a backup...but good habits prevailed so
I did a quick 180 and returned to MGM (which was close...I had just left).
Today my guy called me to tell me that the gear had broken, there was metal in
the engine and...well, it is the precise opposite of all good. I shudder a
little to consider some of the possible outcomes if I had just shrugged it off
and flew on...the engine didn't sound one whit different. Probably would have
when the pistons started coming through the crankcase, ya reckon? It was a
fairly mild IFR day, but...
We're going to pull the engine and send it back to Cunningham to get it fixed
right. I've called the supplier of the latest rebuilt alternator and he is open
to at least discussing making me whole.
My local shop installed an overhauled alternator from a
company whom I am not...at this point...naming. It was purchased by Abiliene
Aero in replacement for the one THEY put in. So at this point, the only company
with a "mark-up" involved is Abiliene Aero...and they did not apply that mark-up
to the alternator in question.
Obviously, the overhaul shop that provided the alternator is at least trying to
find out how much my local guy is responsible, as is reasonable. I guess at this
point I'm just trying to define the cast of characters, and understand who owns
the responsibility. My local guy is calling it a flaw in the driveshaft, which
seems pretty reasonable. If that flaw is in an overhauled part, seems like the
overhauler is the guy."
Be careful out there with these geared alternator
installations. It is interesting to note that this was indeed an elastomeric
coupler configured alternator. Stay tuned for further reports as the failure
analysis on what caused this type of failure moves forward.
Here are additional pics from this analysis:
The current thinking thus far is that this was a
gear lash setting problem. Stay tuned for additional data and results of the
anaylsis. Here is a Beech
Talker Ed B.'s comments:
Based on the gear photo it appears that the gears were too
closely meshed. Yes, that would most likely be cause by the alternator being
mounted too far back, i.e. towards the ring gear, in its mounting hole.
As we discussed a few weeks ago, one would need to do a measurement and
tolerance stack up study of the parts to find the real culprit. However, to do
that would require access to the engine design drawings. Short of someone being
kind enough to offer those up it seems that it would take a subpoena to get a
peek at them. Dimensioned surfaces that come into play are all of them that
affect the gear interface, e.g. crankshaft ring gear mounting flange, case
thrust bearing surface, alternator hole diameter and center, alternator mounting
flange dimensions and center, etc.
As for measuring the lash, it does seem to be a PITA. As mentioned above,
PlastiGuage could be a candidate. I have also read that Experimental
builders employ lead solder to accomplish the task. The problem with both of
those methods is that the alternator needs to be removed after the lash is
checked, which provides another opportunity for error during reinstallation.
Plane-Power describes the best lash measurement procedure that I have seen for a
gear driven alternator, albeit not an IO-550. They require that lash be verified
at the alternator fan after the alternator is installed. They cite a measurement
of "typical lash .075".
Rough math says that that would translate to a lash of about half that, or about
.032", at the gear interface. That's huge and indicates to me that the ring gear
is expected to come forward about .022" due to dynamic flexing under full load.
A gear lash of .005"-.010" is what I would expect to see for a full load design
value in this arrangement.
Interesting stuff. Not rocket science either, but it does take a little finesse
to properly install that alternator. It's not a "plug-and-chug" deal.
Another Geared Alternator
Failure Trashes Engine
Be sure your mechanic follows this
SB from TCM regarding the
installation of the alternator coupling assembly!
Bonanza owner Ron V. reports his geared
alternator failure:
"The solid steel alternator
shaft broke inside the alternator allowing the stub to fall into the engine
oil sump while the gear and clutch assembly bounced around in the crankcase. I
have seen another instance where this resulted in the entire crankcase
breaking open, removing the alternator and a lot of oil from the engine.
Although the damage to the ring
gear was nowhere as obvious as Jim's, upon engine teardown, the crankshaft was
found to be damaged and had to be replaced. Magnefluxing revealed small cracks
in the crank around the ring gear mounting holes. Two months and Daytona
Beach, FL and $17,500 later, this V35B was back in the air.
TCM had a period when some
engines' alternator mounting pads were improperly machined resulting in an
overly tight fit when installing the alternator. The failed alternator shown
here replaced another that had the lower left hand mounting lug broken because
the alternator would not properly seat in the mount. This was discovered when
trying to locate the source of a minor oil leak that found its way to the
windshield."
Here is another way that a
geared alternator comes apart - putting washers in the assembly that don't
belong in there!
TSB Final Report
A07W0186—Engine Failure and Collision with Terrain
On October 26, 2007, a privately operated Piper Malibu PA46-310P was
en route from Salem, OR, to Springbank, Alta., on an instrument flight
rules flight plan. During the descent through 17 000 ft at approximately
55 NM southwest of Calgary, the pilot declared an emergency with the
Edmonton Area Control Centre, indicating that the engine had failed. The
pilot attempted an emergency landing at the Fairmont Hot Springs airport
in B.C., but crashed at night at about 19:12 MDT, 11 NM east of
Invermere, B.C., at approximately 3 633 ft ASL in wooded terrain in the
Rocky Mountain ranges. The pilot and two passengers were fatally
injured.
Read the whole story
HERE
TCM Emergency
Lifter AD 2009-24-52
This pic was found in the TCM service bulletin regarding
abnormal lifter wear. I'll refrain from categorizing my thoughts about this part
.
TCM Grounded the affected engines, read
HERE
The Emergency AD is
HERE
Prop Governor Arm Wear
BeechTalker Brian E., found the prop control cable rod end to Woodward prop
governor control arm connection loose. As you can see in the picture it has been
loose for some time and the control arm has become oblong.
5 clap smilies to the first guy who can tell me that this control arm is not
Beechcraft PN 35-944051-1 (Bonanza IPB fig 47 item 23), which supersedes in
RAPID to 35-944051-13 and costs $317.89.
10 clap smilies for anyone who can recommend an alternate CSOB source of supply.
He found 3 cases where this had previously happened to ABS members on his trusty
ABS CD, but no PN or source of supply. You might want to put an eye on yours.
Run the prop control full in, and then back it off 1/4". You should be able to
see it from the left gill door.
If you can help Eric, contact him at
BeechTalk.
What Battery Acid Boil Over Can Do
This picture is courtesy of BeechTalker, Mark O. and his A36.
He's moving to a sealed Concorde battery after this event. See his BeechTalk
thread
HERE
See a battery box refurb narrative
HERE if acid had destroyed or damaged your
battery box.
How Are Your Exhaust Flanges?
Are your exhaust manifolds original >30 year old units? Well
if so, keep an eye out for weakening in this area as well as all other areas of
this critical engine component. Hey, does a >30 year old exhaust manifold owe
you anything? I didn't think so!
It's also a great idea to have some form of CO detector in
your cockpit. Check HERE for a CO detector
narrative.
Manifold Pressure Gauge Leak
Baron C55 owner Steven F. noticed issues with his MP readings
and posted this to the Beech List:
I have a C55 Baron with 520's and have noticed
that the MP needles during run up were off about an inch of pressure. Over a few
months they were a little more than an inch of MP during idle, run-up, and in
landing config. I helped with the annual as always and paid extra attention to
the induction hoses, making sure they were all tight and in good condition. I
also removed the ball valves in the induction tubes, cleaned and replaced. It
did not make any noticeable difference on the next flight.
After the 4 hour return flight from Sun N Fun I placed the mixtures rich, props
forward, with the throttles around 17" of MP to land, I got a gear warning horn.
I had about 5" less MP on the left engine compared to the right side with the
gear not down it was enough to cause the gear warning horn to sound.
Talked to my IA again and he still believes it to be a MP problem. I plugged the
ball valves on the induction tubes and conducted another run-up, no change.
With both engines at 1K RPM I have 15" left MP and 22" right. at 1700 RPM 17"
and 22"
At TO power and rolling with everything forward I'm at 2,650 on both and 28" on
both.
After much troubleshooting, here is what he found behind his
panel in the area where the hard line gauge plumbing came in contact with
defroster ducting:
Great find Steven!
Note to selves: while you're crawling around checking your
airplane, be especially mindful of ANY chaffing of ANY hard lines with ANY other
pieces of the airframe or structure. Applying some PVC tubing split down the
middle or other hose material held on with wire ties will do wonders for
eliminating these kinds of issues.
On my last annual I was on "chafe patrol" in the area of the
landing gear where the fuel lines come in from the wings. Here are the results
of that "patrol"
There are some very close places in that area for those hard
fuel lines to rub on!
What Size Piston Did They Put in My Engine
This is what was found after a shop disassembled a
Beech Talker's engine 71 hours after a complete top overhaul! While not
confirmed, several engine gurus have commented that this looks like an
incorrectly sized (oversize) piston placed into the cylinder bore. I guess
blindly slamming cylinder components out of the box onto an engine is not such a
good idea?
Piston Destroyed - Mag Timing?
Per Kent F.: At about 1100 hours since engine overhaul in 1982. I think it
has been eroding for some time. Plane had new mags and plugs installed during
last annual in November, about 20 hours ago.
Wonder if the mag timing was correct?
Flap Motor Run to Failure
Here is a 24V flap motor out of a Baron with an estimated TIS ~6,300hours, however, it
clearly does not owe it's owner anything. It's been run to failure and the
armature is toast.
Below is a picture of the brush that came out of it compared to a new brush.
If your flap motor has been in service for a very long time, pull it out and
have it serviced by a professional motor shop. Don't get stranded and have the
extra expense of NDA charges to get back to being airworthy again.
Cessna Nose Fork Prang!
Here is what the submitter, Steve W., says is the story:
Years ago I annualed an old C172A for a guy whose long time "mechanic" had
passed away. Noticed the nose fork pretty early into the project, & asked the
owner about it;
"Yeah, so & so hit a curb with it a few years ago......'Jake' (the dead guy)
said it would be OK."
I guess it would be OK, since the gear just hangs out there in the
breeze....LOL
If you've got maintenance pictures worthy of this "Rogues
Gallery" Please
E-mail them to me with your details!
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Rogues
Gallery of Maintenance Nightmares