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N98SN has just over 210 hours on its clock now in 11 months of joyful
flying from coast to coast to coast and everywhere in between. I'm
getting ready to do my first annual, so I thought it was a good time to
reflect upon the last year. Here are the problems so far, with the last
one the most noteworthy:
1) leaky wing, was leaking out of wire conduit, factory defect,
repaired
2) leaky center tank, drilled a hole in transfer tube during
construction, repaired
3) inner doors partially closing premature, fixed by switching back
to the stock pump from the "hotrod" 4p one, tried new sequence
valves with no luck, only thing to fix it was switching pumps
4) trouble keeping paint on leading edge of wing, still looking for
a solution
5) pilot outboard elevator hinge bearing play, replaced, play
again, still looking for solution, will change next week at annual
6) "early" CFS EFIS hard-drive failure, known problem, replaced
under warranty, no problems since, wonderful system
6) "early" CFS EAU oscillator failure, known problem, replaced
under warranty with updated chip, no problems since
7) Trutrak AP servo water damage (from paintshop), replaced, no
problems
8) Trutrak AP zapped by static, sluggish, sometimes lock up on boot
up, repaired under warranty, no problem since
9) 4 Lancair solid state trim boards zapped by static, sometimes
elevator would go, sometimes rudder, would start with display
acting up, then trim would fail. Solution: replaced with a
mechanical relay board with 6 relays, supplied by Infinity Aerospace,
has worked flawlessly for over 2 months. Need to get Lancair Avionics
to build me a trim display with two standard 10 segment Ray Allen
displays to replace the fancy one that hooks to the solid
controller that kept failing
10) Faulty fuel indication from fuel probleswhen TX on radio.
Manufacturer from Bend (EI I think) supplies a new set of freq to
voltage chips to attach to the probes but haven't had the wings off
yet to do this.
11) Burnt out nav bulb, replaced
12) One Precise Flight (maker of the crappy trim board also) speed
brake still won't work. These have been flakey since day one. Need
to send off. Don't really use them though, or haven't had the
need yet.
And the biggie:
13) Brake pads wore out, completely, down to metal. Replace 4 pads,
pins, and one disc. History: I check the brake pads every
pre-flight, but evidently I didn't know exactly what to look
for, because I almost got myself in trouble. About two months
ago, at about 150 hours, I noticed they were getting worn pretty
good, appeared to be half way. I made a mental note to replace
them at annual. I continued to check them, and my inexperience with
these pads led me to believe they would last until annual (this
month). On 5-22, I traveled to visit fellow Legacy builder TomV at
TN44 (3500') just south of me 25 minutes in TN. After landing I
noticed for the first time the brakes felt as if they were dragging
(this will become important later). I taxied in and noticed we had a
hard time moving the plane around. Well, we got it finally, and I
told Tom we'd check it before I left and maybe have to bleed it if it
was still sticky and inspect the caliper. I again looked at the
pads and they again appeared worn, but still seemed (only seemed, to
my untrained eye) to have some life left. We departed later that day
with no problems, and headed back to homebase 6I2 in KY, no problems
there, noticed a little dragging again, but nothing major. On 5-24,
I departed 6I2 at 10:30pm (dark) for a night hop to Charleston, SC
for a seminar. On climbout, I tapped the brakes to start my
process of gear retraction. I had no pedal on the pilot side. I
turned Otto on and let him fly, and I slid over and tried the co-pilot
pedal. Nothing. I turned the landing light on to light up the gear
well, and turned on the pilot gear wheel camera. Ah- ha...fluid
puddled on the inner door. Ok, decision time: do I turn around
and land at a 50x5000, or do I continue on to CHS and land at a
150x10000. I chose the later. The only problem was it gave me 1.5
hours to agonize about the outcome. However, it also gave me ample
time to plan my strategy. At 30 miles out, the controller handed me
over to CHS AP. I advised them of the situation, they said I was the
only one around so it was no problem. I declined emergency equipment,
just said I might have to go around. My plan was to land to the far
left, hold it straight with rudder as long as possible, let it roll to
a stop without brakes....if I had trouble, I was going around and
giving it another shot. Everything worked out well down to about 30
knots, at which point I started to lose rudder. I tried to brake a
little and that started me right, so I added a little burst of power
to get me back to the left. Again a little brake, and again right as
expected. Another burst of power with an overcompensation to the left
for the arc I was making got be squared away, I braked to the right,
got it slow enough I felt good and ground looped it to a stop. I
probably did over 100 circles to get it clear of the runway while I
was waiting for a tow. Very interesting experience.
Lesson: Replace pads every 100-150 hours. What happened was the pads
were wore enough that they were allowing the caliper piston to extend
enough that it actually starting binding (the stickyness I had
experienced at TN44 and 6I2) and eventually allowed the seal/oring to go
and lost all fluid and pressure.
Hope someone learns from this and doesn't have my same experience. I
had always planned to replace them at annual, as that's what I heard
most people do. However, I guess I fly more than most (200+ hours a
year), so I need to do it more often.
Ponder: The pads cost 4.57 a piece and less than an hour to change,
hardly worth the tragedy it could have caused to me or my bird.
Question: Any other gotchas like the brake pads that should be
inspected and replaced at regular intervals?
---
Shannon Knoepflein --- kycshann@kyol.net
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