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The complete list of common failures ⚠️⚠️

romanov

Well Known Member
Mighty aviators,

I'd like to make a complete list of common failures
that have really happened to you or the people you
know.

Please, if you know about any of:

  1. EFIS failures
  2. fuel line failures
  3. electric failures
  4. engine failures
  5. alternator failure
  6. MAG failure
  7. sensor failure...

... or any other either common or rare failures that happened with your plane or any friend of yours -- tell
about it, please.

Let's keep the description brief: just what happened
and what saved the day. And, optionally, how likely it
is to happen (in your opinion).

I think, this list will be extremely helpful for new
builders, and it will help to know what backup
systems to design.

Respect,
Roman.
 
Lots can be learned from others experiences the only trouble is with a home built as there is little standard in the building process when it comes to installing equip and the routing of cables and lines etc. look at how many diff inst panels there are out there and the associated wiring routing? All of yr list isn't unique to Vans machines but apply none the less.
My ignition switch finally shorted out on a circuit bus bar after 18 years in service (RV8 I didn't build it) so to me electrical faults are some of the most concerning. Luckily I was on the ground when the cockpit started to fill up with acrid smoke! Airborne could have been entirely diff!
Be interesting to hear others stories.
 
"Failure to set a high standard for craftsmanship" is the most common, probably more so than the sum of all other failures.
 
You forgot to list the loose nut behind the stick.

That is probably the biggest cause of accidents.
 
Jamnuts. Jamnuts. Jamnuts! I have only found 2 airplanes WITHOUT loose jaunts in over 10 years of inspections. On the most recent Intitial Certification I found 14 loose jamnuts. :(

Vic
 
I will throw alternator failure out there because it seems to be the most common failure that can be avoided.

When I was building my airplane I noticed lots of alternator failures. Back then the standard alternator was the automotive one. Since then lots of people started using the plane power one and failures became more prevalent. A Savvy Russian Aviator told me about B and C alternators and electrical parts. I used everything that they had to offer including their voltage regulator. That Russian Aviator has been flying for over 4,000 hours on his original alternator and I have 1000 hours on mine with no failures. I'm totally sold on B&C alternators and starters.

:cool: CJ
 
Once I got started on this, I came up with an impressive (to me) list, but impressive in the wrong way. Lotsa planes have needed the brakes bled, so that's not listed here. On the airplanes I've flown / rented:

Rented planes (2000 hours)
* Bad spark plug on first flight after annual, partial power loss;
* Carb heat cable came loose, found on runup;
* Hit a duck on short final at dusk, they made me pay the deductible;
* Vacuum powered DG failure, several in flight. Not sure I've ever had a pump failure, though:
* Flat tailwheel (Decathlon), discovered on rollout;
* Flat main wheel discovered on rollout (Cessna, kept it on the runway);
* Split flap condition in flight. I let the demo pilot land the plane;
* Discovered in flight that both VORs were way out of spec and unusable;

RV-4 (bought) (that one was a real POS but fun to fly) (350 hours)
* Rudder cable came loose from pedals after I changed nylon locknut to castellated to be "safe." My shoe had eventually broken the cotter pin. Discovered in pre-flight;
* Builder mis-drilled the rear spar attach so the plane had a siamesed hole filled with a half-moon spacer;
* High oil temperature because the oil cooler had been mounted against the cowl and there was no room for air to exit;
* Brake rotor came loose from the wheel. Discovered on taxi out;
* Took mags in for overhaul. Knew I was in trouble when the tech said that two of the washers (or something) were upside down, and that they were not resuable;
* Exhaust system failed on takeoff. Too many welds made for a hot spot that failed and part of the exhaust system came loose inside the cowling;
* Navcomm failed, ferried the plane NORDO from Class C to Class D and back;
* Replaced one fuel sender and the dual gauge, but fuel gauges still didn't work;

Cessna 175 (600 hours)
* Failed attitude indicator on a crummy VFR day. Extraordinarily distracting;
* Loose landing gear attach bolt missed at pre-purchase annual;
* Voltage regulator failed in flight. Caught promptly because the ammeter was in front of the pilot;
* Fuel quick drain would not shut off, fixed at Oshkosh by the emergency repair folks;
* All flight control surfaces and horizontal stab damaged in a microburst while tied down and controls locked. I did the preflight entirely out of habit when I didn't feel like doing it, and good thing I did -- the rivets holding the elevators to the control linkage had all sheared;
* High vacuum due to clogged filter;
* Navigational problem due to misprint on a sectional chart;
* One fuel gauge worked well;

AirCam (bought) (100 hours)
* Rotated fuel pickup caused 8 gallons unusable in 14 gallon tank. Two inflight fuel exhaustion events, one in cruise, one on short final;
* Vertical fin mis-installed due to poor illustration in the manual. Repair had the pop rivets installed from the wrong side -- one of them I could pull out by hand;
* Fuel gauges sort of worked, mostly;

RV-8A (bought) (25 hours)
* Had it for less than a year, no problems. When I went to sell it, the buyer's agent asked me what I could tell him about the plane. I told him that he had performed the last annual...
* Fuel gauges didn't work well;

RV-8 (bought) (100 hours)
* Lug on fuel pressure sensor broke off;
* Headset failure (and on other planes);
* An absolutely gorgeous plane, currently for sale;
* Fuel gauges don't work well;

RV-9A (bought) (200 hours)
* Idle set too high, plane barely slowed down on rollout;
* CHT ran high on hot days, attributed to high EGT. Tightened up absolutely everything on the baffles, replaced carb with different model, didn't really solve it, but problem seems to have gone away on its own;
* Throttle would not go in all the way, probably sticking accelerator pump. Discovered before engine start;
* Fuel gauges carefully calibrated but still don't work.

Budd Davisson said that if you have a choice between a used homebuilt and a used snake, buy the used snake. I tell folks new to homebuilts that if they're looking to buy, they better be prepared to deal with all kinds of things.

PS. The RV-4 also had the landing gear seriously toed-out. Pulled the motor mount, had the holes filled in the motor mount and the gear legs, re-drilled in proper alignment. Magnafluxed the motor mount and found cracks, got them re-welded. On the Cessna, had the engine off and also found cracks there. The only welder around was certified but lost his paperwork in a flood. Solution was to magnaflux after the repairs, and that got everything blessed.
 
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- I had a Dynon GPS receiver fail during flight (VFR).
- Turn & Bank indicator failure.

Noteworthy for both failures is that the devices were quite new - less than 200 hours.
 
I'm sorry, but this thread doesn't make any sense. You are simply going to end up with an enormous list of everything that can possibly go wrong with an aeroplane.........
 
Brakes

A couple times a year someone asks for assistance because their brakes have failed. Usually it?s because the pads have worn down and the piston has traveled far enough to allow a leak. This is a maintenance and upkeep issue.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Good Lord Ed....post number 7.......I would not, for the love of money, be on board any aircraft flying or parked with you. Being snake bit would be an improvement. :D
And you posted only the items you could remember. But, then again, you?re still ticking. Reminds me of a Marine C-130 driver I flew with. He destroyed 3 C-130s though no fault of his own and the FOs were getting reluctant to show up.
I told them look the fact he was still alive, a testament to his skills.
Of course, crawling away from all the wreckage didn?t give me much support.
I can only remember couple of minor items in 48 years...
so far, knock knock

R
 
so far...

Dynon D-120, Brake seal, EGT sensor connection, starter, nose tire flat (hole in tube), loose wheel pant screws all the time...
 
I hope my wife doesn't read this thread. It's hard enough to get her to ride with me already. I'm not comfortable with where this thread is going...
 
Early SN RV-12...

  • Master relay failed open.
  • Elevator trim PWM (pulse width modulator) failed. Replaced with Ray Allen.
  • Ducati voltage regulator failed (happens to everybody). Replaced with John Deere VR.
  • Flightcom 403 internal power transistor mounting screw vibrated loose and fell onto circuit board causing short.
  • Loose connection at spark plug terminal caused arcing / RPM drop.
  • Missing / broken exhaust springs (912 Rotax). Replaced with stainless steel.
  • Dynon D180 IAS inaccuracy. Returned to mfgr for repair.
  • EGT thermocouple failed.
 
Dynon remote magnetometer hard fail (rain)
Dynon non heated pitot tube fail (LOTS of rain)
Dynon D-10A screen fail (backlight died)
Bendix RSA Injector line broke at injector
Hartzel CS prop threw 4 inches off the tip (minor nick on TE wasn't dressed)
 
A couple times a year someone asks for assistance because their brakes have failed. Usually it?s because the pads have worn down and the piston has traveled far enough to allow a leak. This is a maintenance and upkeep issue.

This can only happen under one of two conditions......

1. Piston is installed backwards.
2. Bore is pitted and O ring lost seal as piston moves out due to pad wear.
 
Common problems...

- Garmin GA35 GPS antenna failure, turns the antenna into a perfect GPS jammer, wiping out reception on all GPS receivers in the airplane
- oil pressure sensors fail (particularly the VDO units)
- mechanical engine-driven fuel pumps fail (sometimes slowly, making for difficult diagnosis)
- electronic ignitions lose timing (much less of a problem these days)
- exhaust valve failure
- radio slid out of mounting tray (somebody forget to tighten into place...)
- dumb pilot stuff like whacking wingtips, tail or prop against immovable objects - it happens!
 
Wrong amperage fuse for flap motor-failed when flaps down and tried to raise after exiting runway, easy fix on ramp.
Starter nose broke off due to kickback-replaced with one with a clutch. Happily this happened in front of my hangar.
2 fuel pressure senders failed. Replaced with different brand .
Flap motor would lower flaps but not raise them without a little 'tug' on the flap-suspect worm gear worn-replaced with new motor assembly and pre-positioning kit.
ICOM A-200 started to have issues, knob would only tune one way, replaced with Garmin GTR-200.
Got stung by Ameri-King encoder issue, changed to ACK A-30.5.
Mostly minor problems, nothing that was immediately threatening.
 
Non-RV -

> Bad spark plug. Replaced plug. Had plug and tools on hand.

> Bad spark plug lead. Replaced lead. Had to find FBO and buy one and have it installed.

> Brake failure. Needed fluid, serviced. Had fluid and did it myself.

> Flat tire. Replaced tube. Required help jacking airplane in wilderness airport. Someone had a spare tube.

> Broken tailspring. Replaced tailspring. Long story omitted, airplane stuck in back country for 6 weeks.

> RPM dropped abruptly after annual inspection. Maladjusted regulator, repaired by authorized service vendor.

The flat tire was on someone else's airplane shortly before take-off. The others happened to me. Good tool set and appropriate spare parts worth having in back country.

Dave
 
Thank you guys for sharing some of your
experience, this list maybe looks depressing,
but eventually it will help us - the first time
builders to prepare better for the challenges.
It is certainly not going to stop anybody from
build his plane.

Keep sharing.

Huge respect
Roman
 
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