Good job Ed.
However, whatever happened to emergency checklists?
(Not that I ever thought to use the ones I had developed when it
actually came down to emergencies. I guess that takes a LOT of drilling:
something is not right -- grab the emergency checklists).
Finn
Ed Anderson wrote:
>
> Certainly not trying to "TOP" Al's door incident - by the way, good
> airman ship and decisions, Al! Glad the damage was no worst that it was.
>
> But several folks who were not at the Texas Round up have asked about
> the "Ed's Incident". For those of you who were at the roundup, you
> will probably want to skip this repeat.
>
> Incident No. 5119
>
> One the way to Texas I had an incident that ended up in with me and
> aircraft making a 7 mile engine-out glide into Craig Field (Selma,
> Alabama). Again - NO! It was not fault of the engine or even the
> subsystems. But, the complete answer is not provided until after my
> litany of the conditions and symptoms - can you figure it out?
>
> I took off on Thursday AM planning on stopping in Mississippi to join
> up with Charlie England and Tracy. After spending the night there, we
> all three would head for Texas. But, the weather (as you are aware)
> has been laying over the southeast for days with rain and more rain -
> but I launched into it anyway as past Atlanta, GA things were forecast
> to improve..
>
> Other than dodging lines of clouds and a bit of scud running, but not
> much, I landed at Alexandria City to the southwest of Atlanta, GA to
> take on fuel. I then climbed back in and fire it up and took off.
>
> I noticed that during climb-out the engine would occasionally miss and
> thought the fuel might have had a bit of water in it, but was not
> really concerned. So I fly on for approx another 45 minutes and had
> just passed Selma, Alabama and old Craig Air Force base, and turned
> west toward Mississippi, when more symptoms began to occur.
>
> It started to act like a case of SAG (fouled spark plugs) where the
> rpm will drop a bit - not dangerous - just nerve racking. But, shortly
> things began to go beyond the SAG symptoms, so I though I might have
> an injector problem (like one sticking open or not opening at all).
> Since our injectors are in pairs, I tried turning off one figuring if
> things got better, then that pair might have a bad injector.
>
> So I turned off one pair and sure enough the symptoms abated a bit
> (more on this later) so I figured I had a bad injector in that pair.
> To be certain I turned this "bad" pair back on and turn off the "good"
> pair expecting the symptoms to really get bad as I would now be
> running on only the "bad" pair - much to my surprise when I turned off
> the "good" pair - the symptoms also abated. So that indicated it was
> not an injector problem - but what?
>
> About this time, I decided to turn the aircraft back around toward
> Craig Field and dodging clouds headed back with the engine
> progressively getting worst. It appeared to be a fuel problem (and
> while that is ultimately the subsystem affected - it was not the root
> cause). The fuel pressure was ranging from zero to 80 psi, other
> electrical things were also misbehaving. I check the voltmeter
> thinking perhaps the alternator had died - but it showed 14 volts. So
> back to the fuel system.
>
> Finally, the engine just stops with the prop standing still - like a
> hood ornament, I'm at around 4500-5000 MSL at this point having lost
> some altitude dodging a cloud (good old GPS just kept pointing to
> Craig Field). At that time I am 7 miles out from Craig Field at 4500
> msl with at stopped prop, a crippled seat cushion and a dry mouth.
> Yes, I know I've been there before, but I don't think you ever get
> "use" to it. I recalled thinking things just can't get worst when they
> very shortly and suddenly - did.
>
> I keyed the radio and made a call to Craig Field at 4 miles on the GPS
> (I'm starting to get good at this) but before I could get their reply,
> I heard a "CLANK" (without the engine running you can hear things like
> that) like a relay springing open (it was) and the entire panel goes
> dead!!!! No radio, no engine instruments, not even a stinking LED was
> lit - only the battery powered GPS. Can you spell "total electrical
> failure?" Talk about a lonely feeling - amazing how comforting having
> lights on and radio - you could almost convince yourself this was just
> a practice engine-out landing, but not when the panel goes dark. No
> engine gauges, no radio, nada!
>
> Well not being one inclined to panic (but I seriously considered it
> for a moment {:>)), I continued toward Craig field - I mean like there
> were lots of other alternatives. Well Once again I found myself in the
> "fortunate position" of being too high, too much altitude. So I put in
> 40 degs of flaps to steepen my rate of descent. But, then I decided
> this time that rather than do the 360 I had done on a previous
> Incident to lose "excessive" altitude, I would try to glide - a more
> or less - regular traffic pattern.
>
> However, I neglected to remember to retract the flaps. So I found
> myself on the downwind around mid-field at pattern altitude (which
> felt normal) until I suddenly realized that you CAN NOT maintain that
> pattern altitude without an engine!!! Duh!
>
> I knew I could never make it to the far end of the runway before
> turning base (toward the runway), so I started my turn immediately, to
> make matters a bit worst - I had been paralleling the runway on the
> downwind leg a bit too close - must have been the comforting feeling
> of being close to safety. This position naturally required a tighter
> turn and as I turned I saw I was likely to miss the runway and land in
> the grass. So I though I need to steepen this turn further (this is
> called COFFIN CORNER), but fortunately glanced at my airspeed
> indicator to see it only registering 80 MPH and my rate of descent
> (normally 400-500 feet per minute) up to over 1000 feet per minute.
> The seat cushion suddenly vanished from this universe.
>
> But the REAL danger in this situation, as you all know, is your
> airspeed gets low, you are in a steep bank which greatly raises the
> stall speed - meaning at 80 mph you are close to a stall in a steep
> turn while your are not in straight and level. So I immediately
> straighten out of the turn - the little voice saying "better to land
> in the grass than get their concrete runway all messed up". So the
> immediate danger of a stall was adverted, but I was still pointed
> toward the ground with a sink rate twice as high as normal (and I've
> manage a few hard landings even with a normal sink rate).
>
> The hardest thing to do when you are sinking at a 1000 fpm a couple
> hundred feet above the ground (with your nose already pointed at the
> ground) is to push the stick forward steeping the dive even more. But,
> I manage to do that and picked enough air speed and energy to flair to
> a nice touch down - not even a bump. I've always been amazed at what
> total concentration does to improve you landing {:>).
>
> Rolled to the end of the runway and had energy to roll off onto the
> taxiway. Got out, check under the aircraft for any evidence of leaks
> and started pulling the aircraft toward the far -off - hangar which
> had an airplane parked in front of it. A nice looking young woman
> comes riding a bicycle out to meet me. Hopped off and holding out her
> hand said "Hi I'm Angie, looks like we'll be spending time together" -
> so things are starting to look up {:>)
>
> So pulled the aircraft in to the hangar where the mechanic came over
> and ask what the problem was. Well, I looked at the volt meter and it
> said the battery was dead. Mechanic put on a battery charger and
> announced "Yep! The battery is dead". So we both concluded that the
> alternator must have failed and not being able to replenish the drain
> on the battery by all the electrical systems such as fuel pumps,
> injectors, ignition coils, etc had drained the battery.
>
> However, there were a few problems with the analysis of a failed
> alternator. First, the low voltage warning light never came on to warn
> of an alternator problem, 2^nd I never notice the voltmeter showing
> anything other than what it should for alternator voltage - like
> around 14 volts. While checking the voltage after the Mechanic had
> charged the battery, I noticed down below that the "essential bus"
> switch was in the battery rather than the alternator position, so
> flicked it back to the alternator position figuring I must have
> accidentally kicked it while getting to some stuff in the baggage
> compartment of my RV-6A.
>
> It was getting late and being a bit tired not to mention stressed, I
> needed to get a rental car and a motel for the night. Did that, eat
> dinner and went to bed after sitting down and drawing out a problem
> tree with the entire major elements of the electrical system.
>
> So next morning I show up at the hangar early and meet Ben, the
> mechanic, the battery had received a charge of only 45 minutes the
> evening before, So I suggested we charged it for another hour and try
> to start the aircraft. Ben suggested a real stress test of the battery
> and NOT charge it anymore. Made sense, so we rolled the aircraft out
> of the hangar. I hopped in, threw a half dozen switches and punched
> the starter button. The engine started on the first prop blade
> rotation - so the battery was clearly OK. The engine is humming like a
> top. So I looked over at the voltmeter expecting it to show only
> around 12.8 volts instead of the 14 volts a functioning alternator
> would produce. Much to my and Ben's surprise the alternator voltage
> read 14 volts. We loaded the alternator by turning on the both l00
> watt landing lights, all fuel pumps, the pitot heat, etc. The
> alternator voltage only drops perhaps 0.4 volts clearly indicating the
> alternator could carry the load and was OK.
>
> So here I am - battery is OK, alternator is OK - engine is purring
> normally, so clearly this was all a figment of my deteriorating brain
> cells. I loaded up the aircraft and launched to do a few circuits of
> the airport - I did so and all was operating normally and so I radio
> them I was head onward to Texas. While flying, my mind could not let
> go of the problem and finally the light came on.
>
> The essential bus switch had (for my entire 10 + years of flying) been
> in the alternator position. The purpose of this switch is to isolate
> the battery from the alternator should the alternator fail - to
> prevent an alternator problem from draining the battery. So in event
> of an alternator problem, you move the switch from alternator to
> battery. Its call the essential bus because you only have the
> essential things drawing from the battery so you wont' drain it as
> quickly. The idea is to give you time (generally around 30 minutes) to
> find a safe place to land in case of alternator failure.
>
> Well, at some point I had either (not paying attention) turned the
> switch to battery thinking I was turning the voltmeter switch to
> battery - or accidentally had move the switch from alternator to
> battery without noticing it by kicking it, etc. However, it was sort
> of protected in its position from accidental activation. It must have
> happened during refueling - as I got approx 45 minutes down the road
> on the battery after take off before quality battery time started to
> deteriorate. As the battery voltage fell due to the load (and no
> alternator link to replenish it), electrical things (mainly computers
> first) started acting up until they could not longer run the engine.
> The injectors would not open fully, etc. Then as the voltage level
> further decreased, the master relay which the battery held closed and
> which connected the (fully functional) alternator to the rest of the
> electrical system - opened up and removed ALL power from the
> electrical system. So no radio, no gauges, etc.
>
> Oh, another little factor that may have contributed, the voltmeter has
> a tiny toggle switch by it marked ALT BAT1 BAT2 for checking
> alternator battery 1 and battery 2 (which I no longer fly with)
> voltages. Down below It a couple of inches and off to the right is the
> essential bus normal size toggle switch - also marked ALT BAT1 BAT1. I
> normally never touch it and don't even think about it. But I could
> have reached for the voltmeter toggle thinking to check my battery
> voltage (which I do as a regular thing) and perhaps distracted by
> something reach a bit further down and instead moved the essential bus
> switch from Alternator to Battery cause this entire event. I know that
> I did not consciously do it. So it is either accidental or absence
> minded activation - either way ends with the same results {:>)
>
> Now it became clear why it didn't matter which pair of fuel injectors
> I turned off - turning off either pair improved the situation because
> it slightly reduced the electrical load by a few amps - and the engine
> ran slightly better for a few moments. The same thing had happened
> when turning off one of the EFI fuel pumps - but what threw me was the
> alternator voltage continued to be normal during this.
>
> After I knew the cause (switch in wrong position), I decided the
> problem was fixed so no reason to return to NC, and I just continued
> on to Texas.
>
> I know some of you may think that removing my second battery was a
> mistake - but, consider this, having another battery could have meant
> I would have been much further from a suitable airfield before they
> both went south. On the other hand, it might have caused me to at
> least think to throw the essential bus switch to the second battery
> and have the Light bulb come on. Who really knows. But, I have in mind
> a simply addition to my electrical circuit that should help in the
> future.
>
> I do want to state that this time when the problems started I DID
> switch fuel tanks - but naturally it had no effect because this time
> it turned out, it was not a fuel problem - not the root cause at least.
>
> So what are the lessons learned:
>
> 1. Put EVERY critical switch on your before-takeoff Check list
> 2. Perhaps put a guard around such critical switches to force
> conscious activation
> 3. Don't (hard not to) get overly focused on what you think is the
> problem - consider other possibilities. I thought it was a fuel
> problem (I even switched fuel tanks this time) - it turned out
> to be electrical in its root cause.
> 4. While the fuel pressure was jumping all over the place and the
> EGT was erratic and engine surging strongly indicating a fuel
> problem - the ultimate cause was electrical. Once the voltage
> got below a certain point the EC2 was still trying to pull the
> injectors open, but with the voltage so low it could not do it
> properly.
> 5. When the battery voltage dropped below a certain point, the
> master relay released and removed the alternator from the
> electrical system and the panel went dark - even though the
> alternator was still working
> 6. Immediately turn to the nearest airfield when serious problems
> occur - THEN work on fixing them. I only delayed for perhaps 2-3
> minutes, but that could have made a difference.
> 7. Watch out for *Coffin Corner* turn when turning base to final -
> airspeed really bleeds off fast with no engine pulling you along
> (and especially with flaps deployed!)
> 8. IF you change your mind about landing approach type - remember
> to reconfigure your aircraft for the last decision - I had left
> my flaps deployed when I should have remembered to retracted
> them. Did that help prevent a Coffin Corner stall and spin or
> would it have put me closer to it?
> 9. You must increase airspeed over the wing to get the sufficient
> energy to over come a high sink rate. Pulling back on the stick
> when the ground is staring you in the face is the natural
> reaction - but, pushing forward to lower the nose is the correct
> action - providing of course you have sufficient altitude!
> 10. Battery life - I had a two year old 680 odyssey battery which I
> maintain a trickle charge on whenever I'm not flying. With two
> EFI fuel pumps, boost pump, injectors, coils, EC2 and radio and
> just having started the engine before take off - this battery
> lasted 55 minutes. Well, the last 5 minutes was not quality
> battery time. So in my case, 30 minutes appears to be a very
> realistic battery life. In fact, had I turned off one EFI pump
> and the boost pump would have gained a few more miles. But, if I
> had recognized the need to turn them off at that time (I
> normally turn them off at cruise altitude), then I would have
> known how to "fix" the problem.
> 11. I've decided to add a Schokkty diode between my essential bus
> and the alternator - so that as long as the alternator is
> producing sufficient voltage, then the battery will be getting
> some charge to replace the drain. I've also decided to make that
> switch position a check-list item.
>
> So what it boils down to - if I had recognized early on that it was an
> electrical problem and not focused so much on the fuel system, I may
> have noticed the essential bus switch in the wrong position. Force
> yourself to examine other possible causes (easy to say - harder to do).
>
> NEVER, NEVER forget that flying the airplane is the first and only
> priority in this type of situation
>
> NEVER, NEVER forget that saving your butt is the ultimately end-all
> priority. When I decided that landing on the grass was preferable to
> putting a hole in their concrete - I just may have made a life-saving
> decision.
>
> If anybody else wants to pick up this baton - I'm ready to hand it
> over - what? no volunteers? {:>)
>
> So that's my story and I'm sticking to it.
>
> Fly safe, guys!!
>
> Ed
>
> Ed Anderson
>
> Rv-6A N494BW Rotary Powered
>
> Matthews, NC
>
>
eanderson@carolina.rr.com
>
>
http://www.andersonee.com
>
>
http://www.dmack.net/mazda/index.html
>
>
http://www.flyrotary.com/
>
>
http://members.cox.net/rogersda/rotary/configs.htm#N494BW
> <
http://members.cox.net/rogersda/rotary/configs.htm>
>
>
http://www.rotaryaviation.com/Rotorhead%20Truth.htm
>
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