This is a little off topic, but just a few days ago Leon had sent a link to
the SDS Racetech site describing their RV6. And now they are making news and
not the good kind. Nobody hurt and the plane is already being repaired.
I thought I should post this even though it is a Subaru powered aircraft
because it shows what can happen to an electrically dependant engine.

Todd Bartrim (happy to have a built-in voltage alarm on EFIS, radio,
x-ponder, GPS & EM2)


02/07/05 A Forced Landing

On January 22/05 we were conducting leaning experiments with the WMS
wideband AFR monitor and turbocharger compressor temperature measurements
with the stainless backplate installed, on a flight between Springbank and
Vulcan at 9500 feet. As we leveled off, it was noted that the electronic
digital altimeter was changing readings 20-40 feet randomly. This was
attributed to rising/ descending air initially. Within 2 minutes, the
fluctuations were 100-300 feet but the air seemed smooth. About the same
time, I noticed that the WMS meter was reading completely wrong yet the
engine was running perfectly. A few seconds later, the GPS went offline. It
was recycled but died again within 20 seconds so I shut it off. When I
scanned the engine instruments, I noted that the tachometer was reading
incorrectly and the Navaid gyro was indicating a right turn when we were not
turning. I suspected a charging system failure immediately and checked the
battery voltage in the SDS monitor. This read 9.5 volts so I knew then that
we had a charging system failure. At the time, I was not worried about
making it to an airport, assuming that the alternator had failed just in the
last few minutes and believing that I had 20-25 minutes of battery power
remaining. In fact, it is likely that the alternator failed soon after
takeoff from Springbank but I did not notice signs of the failure until the
battery was well over half dead.

Calgary Terminal called to clear us from his zone but his transmission broke
up. We could not respond and shut off both comms and squawked 7600 for about
30 seconds before the transponder went down. I shut off all other
non-essential electrical loads at this time. I estimated Vulcan airport at
12-15 miles away which we were heading straight for. About 4-5 minutes
later, the engine started to run rough as battery voltage was down to 6.5
volts. 2 minutes later, the engine started to cut out intermittently. By
turning the low pressure fuel pump off for 15 seconds at a time, partial
power was restored for a few seconds. One minute later, the engine
essentially ceased running but the prop was still windmilling. I settled on
90 knots as a glide speed with the VSI around 1000 fpm down. About 3 miles
out, our altitude looked fine to make the runway, high if anything. 1.5
miles out and it was clear that we would not make the runway. I was worried
about 2 ditches, a road and a man made waterfowl dugout off the far end of
the runway and did not want to arrive high as we had no flaps. This turned
out not to be a problem as we would be well short of the threshold. I made a
shallow turn into wind to land in a field parallel to the plowed furrows.
Airspeed bled off rapidly in the turn and I had to keep pushing the stick
forward to maintain 65 knots. The deck angle was somewhat scary. Don't
stall! don't stall! was going through my mind vs. the alarming deck angle.
At about 20 feet up, I initiated the flare. We touched down level or
slightly nose down as there was insufficient stick and energy to complete a
proper flare. The nose gear gave way, then the prop and there were some
expensive crunching sounds. We slid to a stop on the partially snow covered/
frozen field in about 200 feet.

The G meter read 7Gs from the vertical impact. I used my cell phone to
contact Edmonton ATC and report the forced landing. As there were no
injuries, we were authorized to move the aircraft by Transport Canada. The
local police, EMS and fire services were extremely helpful and efficient.
They even arranged for a nearby trucking firm to recover the aircraft for
transport back to the airport. Joyline Transport did an excellent job
organizing a cherry picker and lowboy at both ends, arranging all permits
and getting VZX back to its hangar. Many thanks to all involved from the
Vulcan area including Wally Walpole, the talented lowboy driver, the field
supervisor and "Woody" from Lethbridge, an interesting personality to be
sure. These people made Vulcan the nicest place to have a forced landing and
the best of a not so good day.

Preliminary investigation showed that the alternator field fuse was blown
for reasons undetermined at this point although some swarf was resting on
top of the fuse holder in close proximity. Whether this was the cause or
simply disloged from the impact will probably never be known. We'll be
perfoming tests on the charging system when the aircraft is repaired again.
The impact sheared the nose leg retaining bolt clean off. The leg punctured
the stainless firewall and battery box and came to rest against the battery
case. The nose leg was completely "pretzelized" with the tire ending up flat
under the cowling. The main gear legs were both bent back an extra 10-15
degrees and the IVO propeller shattered 2 blades on impact. Various wheel
pants and fairing were also damaged and both brake rotors were bent. No
structural airframe damage was discovered and repair is under way. Thanks to
Van's for designing such a robust airframe and I'm glad I was in a metal
aircraft.

Lessons Learned and Applied

Thinking in hindsight on what was not readily apparent at the time of the
emergency:

The low voltage warning light was likely ON for 10-15 minutes and remained
unnoticed by me because I was busy recording AFR data. The warning light is
not a flashing type which is much more likely to attract attention. A 95dB
warning buzzer will now be added so that a charging system malfunction will
be apparent immediately. I strongly recommend an aural warning vs. a light.
The delay in noticing the failure resulted in the forced landing. I believed
that I had 20-25 minutes of battery power remaining when the failure was
detected but had more like 10 minutes at that point.

Pilots always talk of instructors throwing impossible multiple system
failures and emergencies at them in training or in the simulator. Well, this
time, we had such multiple, progressive system failures and did not
recognize what was happening until the third device started giving odd
readings. It is worth thinking about odd readings rather than dismissing
them. You might save valuable time.

We rely so much on GPS but the "Nearest Airport" feature does not help much
without electrical power and a dark screen. Having a map handy and marking
last known position every 10 miles is not a bad idea. Glass cockpit
advocates take note on the reliance of these on electrical power. We had no
time to Mayday or really squawk a comm failure before power was lost. This
could be serious in controlled airspace.

We had no battery backup as this was deemed unnecessary, thinking that the
alternator failure would be immediately noticed and that I'd have 20-25
minutes of flight time to find a suitable landing spot or airport. A second
18 amp hour battery will be added with a separate switch, independent of the
master solenoid. I was worried that the master solenoid would trip open at
the low voltage, effectively signing everything off. Fortunately, the hold
current required on these is quite low but this is an extra drain on the
battery.

Most of the electrical devices were effectively offline at around 9 volts.
Fortunately the SDS ECU and coil pack functioned down to the very last along
with the fuel pumps, even at 6.5 volts where the battery is virtually dead.
SDS has voltage compensation for the ignition and injector drivers which
helped in this situation. Does your ECU have this?

Should I have picked a road or smoother field immediately rather than
heading for an airport 20-25 miles away? Well, I would have if I'd known how
bad the battery state was.

I should have pushed the throttle up and climbed to get as much altitude as
possible to arrive very high OVER the airport but again, I thought I had
lots of time.

With total power loss, the aircraft does not glide as well as it does even
with idle power. The 3 blade prop has considerable drag due to its flat
plate area. This is something you can't practice, but am aware of now. The
deck angle to maintain airspeed is steeper than in training. Maintain speed
at all costs and have a margin of extra speed for the flare as the elevators
are less effective with no power. Train often for engine failures. It CAN
happen to you! I'm glad that I did train fairly often. There was no panic
and I did most things instictively.

Wear your shoulder harness! We always do but it is surprising how many
pilots are injured or killed with them dangling by their shoulders. Have
winter gear with you when you winter fly. We did, even though it was a
pretty pleasant, sunny, winter day. Remember, it CAN happen to you!

Use all resources possible. If you have another pilot with you, hand some
responsibility over to them for map reading, calling out airspeeds,
altitude, reading emergency checklists, giving you flaps etc.

Damage will be repaired. Systems will be changed. Checklists will be altered
and training will be intensified. I pledge not to forget the lessons learned
here and am very happy to still be here to write this.

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