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Big Pistons Forever
16th Aug 2020, 16:57
The hardest and most complex situation I ever had to deal with was during what started out as pressurization test flight after maintenance on a Cessna 421C about 20 years ago. The airplane was new to the current owner and had proved to be a maintenance nightmare. The previous owner had not only skimped on repairs but had performed negative maintenance ( eg disabling warning systems by cutting wires rather then repairing the failed sensor). The weather at my home airport (sea level long runway with ILS approach) was 400 and 3 wind calm. I was in solid cloud from 400 ft to 7000ft and then broke out into clear conditions. Climbing trough about 8000 there was a very loud bang, a bright flash from behind the right side CB panel and a sizzling sound and strong electrical burning smell. I immediately turned off the battery master and alternator switches and got out the fire extinguisher.

When it became apparent that there was no fire I took stock of the situation. Almost every CB was popped so there was no obvious item that started the cascading failure. The airplane had an Electric AC powered Attitude Indicator and HSI and a 28 volt turn and bank on the left side all of which were not powered with the battery master off. It did not have co-pilot gyro instruments. Other than the electrical issue the airplane was operating normally


What t would you do ?

India Four Two
16th Aug 2020, 17:38
I would have waited for a CAVOK day! ;)

Big Pistons Forever
16th Aug 2020, 18:19
Yes this is a pretty good example of “it is better to be on the ground wishing you on the air, than be in the air wishing you were on the ground”. Waiting for CAVOK conditions would have meant at least a weeks delay and more likely 2 weeks given the prevailing and forecast weather. In fact the flight had already been pushed a day as the weather was even worse then. For commercial reasons
a delay was not desirable and the aircraft had no significant defects prior to takeoff.

I will also note that I was a lot younger then and there is no doubt I am much more risk averse now, partly as a result of this incident !

Maoraigh1
16th Aug 2020, 18:25
Was a vfr alternative within range? Did you have a handheld?

Big Pistons Forever
16th Aug 2020, 18:58
No good VFR basically anywhere within fuel range. This was on the West Coast of Canada. All the coastal airports were IFR and all the rest in range were basically in valleys which were clagged in. I just checked the flight was 24 years ago so I did not have a cel. I did have a handheld radio but I did not have it with me which reflected some more less than great decision making on my part

What prompted me to write this was the thread in the Instructor forum discussion how to deal with complex emergencies. I am still here so I survived, which I think was due to the fact that after a bunch of bad decisions I made some good ones. Any complex emergency demands a very systematic approach to problem solving and decision making. As I wrote in the instructor post I went right back to the basics of "Aviate, Navigate, Communicate" to guide and prioritize my actions

Discorde
16th Aug 2020, 20:35
I seem to remember many years ago there was a procedure for getting assistance for an IMC let-down if you had no instruments and no radio. Basically you flew a 1-minute triangular pattern which you hoped would be observed by ATC radar. They would send up a shepherd a/c who you would formate on to guide you down.

tmmorris
17th Aug 2020, 05:19
Well, unless Discorde's suggestion worked, I guess you’re going to have to pull any remaining CBs that haven’t already tripped, reset the battery master and see what you can get working,

And probably try the alternator, too, as I don’t think there’s any evidence that was the problem. Although it’s interesting so many CBs popped.

Did the CB for the alternator field pop?

More generally, which CBs didn’t pop?

340drvr
17th Aug 2020, 11:47
Complete electrical failure and absolutely no gyros: If you truly can't stay in visual conditions, there's really only one last resort. With a "known" 400 foot ceiling, get over flat terrain, or in this case, maybe even over the ocean, setup and trim for a good stabilized descent, hands off the yoke, rudders only for any corrections, let down thru the clouds while watching altimeter, hope you stay stable thru the goop until underneath in visual, then scud-run. Turbulent air would of course lower the percentage of successful outcome, and probably more likely with a 421 vs. lighter airframe like a 172. Absent any outside assistance such as a "formation shepherd" from the Coast Guard, or such, that's about all you can do.

B2N2
17th Aug 2020, 13:12
.....I’m still thinking on this one.

sycamore
17th Aug 2020, 14:43
Check the MSA of the area...presumably you had a map AND KNOW WHERE YOU ARE...try restoring the battery first ,for the a/hzn/t-slip,and HSI.Check the OAT/ICING,try a radio,and/or the ILS(have you a Jepp.chart for base ,or anywhere...? As you should have plenty of fuel,do all this in VMC...if you have an ELT/PLB,TURN IT ON,IT MAY HAVE A VOICE CHANNEL,and people will know you have a problem...someone may be able to come and be a `formation `lead`down the ILS....Do the radio/instruments/ils work or have you any electric power...at a minimum you need the `turn & slip`...conserve electric power in VMC...

My plan would depend on the ILS if I can position to join it at 8000ft/30 miles(300ft/mile),U/C down,1/2 flap,carb air,pitot htr on,DVpanel slightly open ,so I can judge the airspeed,having checked the `standby compass and t/slip,descent power.
Plan `B`,would be similar if I went out to sea if no electrics..
Plan `C` would be to put on my parachute and jump before reaching the coast.....

sycamore
17th Aug 2020, 16:04
A bit more,as it happened to me once...I had been to an air-race,and was flying a Cassutt.After the event I had to return home to my RAF base in NYorks across the Irish Sea and NY moors. The weather was forecast to be fine for most of the route,but layered over the moors and broken over destination.I was going in formation with another Instructor in another type with better instrumentation,but also non-radio..my aircraft had an ASI,altimeter,RPM and t&slip,standby compass....We briefed the formation ,and arrival and if it was `iffy` we would orbit ,other a/c would pop down,then pop backup for a formation descent....so ,I orbited,and orbited,adjusting for forecast wind..and waited,but no sign of the other a/c ,or any `sucker holes` ..so, time to set up for an IMC descent on limited panel compass and t/slip,and down I went into the `murk` ,fortunately it was not turbulent,and eventually it got `darker` until we(me and Cssutt) popped out of the clag at a reasonable height,and not far from my base....We later had a `meaningful` discussion,as he`d `forgotten` the brief......

Big Pistons Forever
18th Aug 2020, 18:44
What I did

When the event happened I was very shocked and momentarily paralyzed because it was so violent. Fortunately a thorough review of the emergency checklist memory items paid off as I immediately turned off the master and alternator switches. At that point my brain froze and I sat stunned in the seat for probably 10 seconds until the brain kicked in. I started by verbalizing out load aviate, communicate, navigate.

So I asked myself what do I need to attain and maintain immediate safe aircraft operation ( Aviate). So first off I needed to determine I was not on fire. I Leveled the wings reduced MP to low cruise quickly checked the aircraft was trimmed for more or less straight and level, then got out the fire extinguisher from under my seat turned off the cabin vent controls and cautiously leaned over to the right side CB panel an ran my hand near it. Definitely warm but nothing burning, the slight electrical smoke haze was dissipating and there were no sounds indicating arcing. So I pulled the emergency check list and ran through it to make sure I had not missed anything

Then I thought where am I going ( Navigate).. The departure flight path was basically over the airport so I established a gentle bank to circle where I was so I did not get too far from my last known position. Clearly I was going to need some instruments and radios to get back on the ground so I pulled all the remaining circuit breakers and then held my breath and turned on the battery master. After a minute when nothing bad happened, I reset the CB for the AI. It came to life and a few gentle turns and pitches proved its operation. I then tried the HSI CB which popped as soon as I pushed it in. I then tried the No 2 Nav which had a dedicated stand alone head and it came to life and idented the local VOR which gave me a radial that made sense from where I though I was. I then tried the turn and bank CB but it popped as soon as I pushed it in. At that point I decided I was not going to push my luck and decided the last thing I would try to energize was a comm. The No 1 Comm CB stayed in and I head voices on the terminal frequency.

At that point I gave a think about what I wanted to do so I could tell terminal the plan. ( Communicate) . The good news is the ILS was on runway 27 so no turning error on the mag compass if I did not accelerate /de-accelerate. I decided I would get terminal to vector me to intercept the ILS from below at 8000 ft ( 1000 ft above the tops) This would allow me to get the gear down with the emergency system and get stable while still VMC. So I got on the radio declared the emergency told then what radial I was on to help the prime target ID and got no gyro vectors. The ILS was uneventful and the calm air certainly helped as I could use the mag compass for heading info. ! broke out at about 500 ft and landed

It turned out that there was some electrical "repair" carried out by the last owner that resulted in a main bus bar being put back without any fasteners to hold it in place. During a ATC commanded turn on the departure it fell off and landed flat on an aircraft frame which caused a massive short. Our engineer figure there was so much juice flying through the airframe it took out a lot of other services. There was a lot of damage and the cockpit ended up being almost entirely rewired at great expense, The good news is several other really scary electrical issues where also found and corrected.

The bottom line is this is the poster child for "use your superior judgement to avoid situations requiring the use of your superior skills " . The fact that I took off that day reflected very poor decision making on my part but I decided to write about this because the use of the trite "aviate, navigate,communicate" mantra was a significant help to me in prioritizing my actions in the very difficult situation I was presented with and so If you are suddenly confronted with a bad situation and are momentarily unsure of what to do verbalizing those 3 words may help.

student88
18th Aug 2020, 21:45
Thought provoking - thanks for sharing.

B2N2
19th Aug 2020, 01:17
I don’t think you gave us enough info on this one in the original post BPF.....:hmm:

cats_five
19th Aug 2020, 08:47
<snip>
The airplane was new to the current owner and had proved to be a maintenance nightmare. The previous owner had not only skimped on repairs but had performed negative maintenance ( eg disabling warning systems by cutting wires rather then repairing the failed sensor).
<snip>

I hope this is something you discovered after the flight.

340drvr
19th Aug 2020, 12:34
Well done, glad it worked out Primary importance to not panic, hard to do if/when things really go bad.
Classic example is the Speedbird 9 story, 747 flameout after flying through volcanic ash, the crew just kept running thru proper procedure, landed safely
https://en.wikipedia.org/wiki/British_Airways_Flight_9
(Hopefully, after repairing faulty circuits in that 421, they installed an independent gyro of some kind, air-driven, or stand-alone battery powered AI).

Big Pistons Forever
19th Aug 2020, 14:18
Well done, glad it worked out Primary importance to not panic, hard to do if/when things really go bad.
Classic example is the Speedbird 9 story, 747 flameout after flying through volcanic ash, the crew just kept running thru proper procedure, landed safely
https://en.wikipedia.org/wiki/British_Airways_Flight_9
(Hopefully, after repairing faulty circuits in that 421, they installed an independent gyro of some kind, air-driven, or stand-alone battery powered AI).

It did have air driven gyros on the copilots side, however both did the AI and DI did not work so they had been removed for overhaul. Like I said the decision to take off that day was not a good one.

Booglebox
20th Aug 2020, 13:01
The airplane had an Electric AC powered Attitude Indicator and HSI and a 28 volt turn and bank on the left side all of which were not powered with the battery master off. It did not have co-pilot gyro instruments

Wow. Was the plane legal with the right side gyros removed? Is there some Canadian equivalent of "GRABCARD"?

I'm a big fan of having as many redundant attitude systems as possible. Am much happier doing instrument flying at night in a 172S rather than a classic 172N or P due to the second vacuum pump (yes, connected in series, but nevertheless). Having an auxiliary electric vacuum pump is also great, as is one of those fancy handhelds with an OBS display allowing you to shoot an ILS in the event of a total electrical failure.
ForeFlight coupled to a Sentry module (or similar) giving rudimentary GPS-based attitude and heading is also good weapon of last resort.

Thanks for sharing this!