X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from EXHUB003-2.exch003intermedia.net ([207.5.74.29] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTPS id 3670467 for flyrotary@lancaironline.net; Wed, 03 Jun 2009 14:32:39 -0400 Received-SPF: none receiver=logan.com; client-ip=207.5.74.29; envelope-from=jwhaley@datacast.com Received: from EXVMBX003-5.exch003intermedia.net ([207.5.74.45]) by EXHUB003-2.exch003intermedia.net ([207.5.74.29]) with mapi; Wed, 3 Jun 2009 11:30:57 -0700 From: Jeff Whaley To: Rotary motors in aircraft Date: Wed, 3 Jun 2009 11:31:58 -0700 Subject: RE: [FlyRotary] Re: Incident No. 5119 Thread-Topic: [FlyRotary] Re: Incident No. 5119 Thread-Index: AcnkdnCjdNkdKiNAShmhabksILc1zAAAe9HA Message-ID: References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: multipart/alternative; boundary="_000_C03ABB0A7362B84BB53D544B3C305E0EF65EB3B355EXVMBX0035exc_" MIME-Version: 1.0 --_000_C03ABB0A7362B84BB53D544B3C305E0EF65EB3B355EXVMBX0035exc_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Ed, Ben, I too have an alternator disconnect switch. Originally I put it in= to test for a simulated dead alternator by disconnecting it and monitoring= the battery voltage over time while driving all the electrics with engine = running ... I was able to live-test it one evening for about 15 minutes. I = intend to leave the switch in but it really should be a detent-type and Ed'= s idea of a diode charger is a good one. The results are as follows; note t= he voltage drops rapidly at first, then stabilizes for a long time, with no= ticeable variations due to engine rpm: Jeff Time Voltage RPM Comments Pre-start 12.89 0 4-5 min 14.5 2500 Alternator I= N 0 13.3 3000 Alter= nator OUT 1 12.38 3600 2 12.26 3600 3 12.22 3600 4 12.22 3600 5 12.21 3600 6 12.21 3600 7 12.20 3600 8 12.21 2700 Coolant= @ 200F 9 12.21 2700 10 12.20 3300 Coolant <= 200F 11 12.19 3300 12 12.19 3300 13 12.19 3300 Coolant 2= 10F From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Beh= alf Of Ben Baltrusaitis Sent: Wednesday, June 03, 2009 12:59 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Incident No. 5119 Ed, Many thanks for sharing your story and excellent analysis! I have forwarded= it to our EAA group. We had a similar problem when ferrying my Soob powered Kitfox. It had an al= ternator on/off switch and the ferry pilot failed to turn it on after refue= ling. It wasn't long into the flight that the tachometer quit. There were r= ed lights glowing, however, some circuits were wired to glow red when worki= ng--not the best situation. Luckily the pilot noticed the alternator switch= in the "off" postion before we lost ignition. After that, the alternator s= witch was always left on. Ben ----- Original Message ----- From: Ed Anderson To: Rotary motors in aircraft Sent: 06/03/2009 12:35 PM Subject: [FlyRotary] Re: Incident No. 5119 Thanks, Bryan, You nailed it why I do share my "most embarrassing moments" - I want to ens= ure that I am the sole participant in such incidents (don't want to share t= he fame - NOT). I may be the only one to make errors - but I strongly susp= ect that there is at least one or two others out there {:>). That's why this list is so valuable - we all feel comfortable sharing our k= nowledge and experiences - even our goofs. While some may smugly sit back = and say "well, I would have recognized the problem and solution immediately= " and my hat is off to them, my only come-back is don't be so certain - I'v= e been certain that specific incidents could never happen to me and found o= ut I was wrong. 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://www.rotaryaviation.com/Rotorhead%20Truth.htm ________________________________ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Beh= alf Of Bryan Winberry Sent: Wednesday, June 03, 2009 12:09 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Incident No. 5119 Ed, Excellent report. And like Al G, excellent airmanship! We may have to hav= e a call in vote, ala American Idol, to determine a "Top Gun" here. Seriously, this account needs to be read by other pilots out there (not jus= t on this forum). Many good lessons learned from someone secure enough to = share their story, even if it alludes to an error. Errors that we all make= occasionally (yeah, even you Chuck Y.) I really regret not being able to attend the Texas event. Well done Ed, Bryan ________________________________ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Beh= alf Of Ed Anderson Sent: Wednesday, June 03, 2009 11:17 AM To: Rotary motors in aircraft Subject: [FlyRotary] Incident No. 5119 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 probabl= y want to skip this repeat. Incident No. 5119 One the way to Texas I had an incident that ended up in with me and aircraf= t making a 7 mile engine-out glide into Craig Field (Selma, Alabama). Agai= n - NO! It was not fault of the engine or even the subsystems. But, the co= mplete answer is not provided until after my litany of the conditions and s= ymptoms - can you figure it out? I took off on Thursday AM planning on stopping in Mississippi to join up wi= th 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 fue= l. I then climbed back in and fire it up and took off. I noticed that during climb-out the engine would occasionally miss and thou= ght the fuel might have had a bit of water in it, but was not really concer= ned. 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, w= hen more symptoms began to occur. It started to act like a case of SAG (fouled spark plugs) where the rpm wil= l drop a bit - not dangerous - just nerve racking. But, shortly things beg= an to go beyond the SAG symptoms, so I though I might have an injector prob= lem (like one sticking open or not opening at all). Since our injectors ar= e in pairs, I tried turning off one figuring if things got better, then tha= t 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 th= e symptoms to really get bad as I would now be running on only the "bad" pa= ir - much to my surprise when I turned off the "good" pair - the symptoms a= lso 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 Fi= eld and dodging clouds headed back with the engine progressively getting wo= rst. It appeared to be a fuel problem (and while that is ultimately the sub= system affected - it was not the root cause). The fuel pressure was rangin= g from zero to 80 psi, other electrical things were also misbehaving. I ch= eck 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 altit= ude dodging a cloud (good old GPS just kept pointing to Craig Field). At t= hat 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 bef= ore, but I don't think you ever get "use" to it. I recalled thinking thing= s 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 rad= io, no engine instruments, not even a stinking LED was lit - only the batte= ry powered GPS. Can you spell "total electrical failure?" Talk about a lo= nely feeling - amazing how comforting having lights on and radio - you coul= d 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 m= oment {:>)), I continued toward Craig field - I mean like there were lots o= f other alternatives. Well Once again I found myself in the "fortunate pos= ition" of being too high, too much altitude. So I put in 40 degs of flaps t= o steepen my rate of descent. But, then I decided this time that rather tha= n 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 o= n the downwind around mid-field at pattern altitude (which felt normal) unt= il I suddenly realized that you CAN NOT maintain that pattern altitude with= out an engine!!! Duh! I knew I could never make it to the far end of the runway before turning ba= se (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 to= o 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 ste= epen this turn further (this is called COFFIN CORNER), but fortunately glan= ced 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 minu= te. 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 - m= eaning at 80 mph you are close to a stall in a steep turn while your are no= t 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 r= unway 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 no= rmal (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 t= hat 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 pa= rked 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 as= k what the problem was. Well, I looked at the volt meter and it said the b= attery was dead. Mechanic put on a battery charger and announced "Yep! The = battery is dead". So we both concluded that the alternator must have faile= d and not being able to replenish the drain on the battery by all the elect= rical systems such as fuel pumps, injectors, ignition coils, etc had draine= d 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 alterna= tor problem, 2nd I never notice the voltmeter showing anything other than w= hat it should for alternator voltage - like around 14 volts. While checkin= g the voltage after the Mechanic had charged the battery, I noticed down be= low that the "essential bus" switch was in the battery rather than the alte= rnator position, so flicked it back to the alternator position figuring I m= ust 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 w= ent to bed after sitting down and drawing out a problem tree with the entir= e major elements of the electrical system. So next morning I show up at the hangar early and meet Ben, the mechanic, t= he 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, thr= ew a half dozen switches and punched the starter button. The engine starte= d on the first prop blade rotation - so the battery was clearly OK. The eng= ine is humming like a top. So I looked over at the voltmeter expecting i= t to show only around 12.8 volts instead of the 14 volts a functioning alte= rnator 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 l= anding 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 loa= ded up the aircraft and launched to do a few circuits of the airport - I di= d so and all was operating normally and so I radio them I was head onward t= o 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 t= he alternator position. The purpose of this switch is to isolate the batte= ry from the alternator should the alternator fail - to prevent an alternato= r problem from draining the battery. So in event of an alternator problem,= you move the switch from alternator to battery. Its call the essential bu= s because you only have the essential things drawing from the battery so yo= u wont' drain it as quickly. The idea is to give you time (generally aroun= d 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 t= o battery thinking I was turning the voltmeter switch to battery - or acci= dentally had move the switch from alternator to battery without noticing it= by kicking it, etc. However, it was sort of protected in its position fro= m accidental activation. It must have happened during refueling - as I got = approx 45 minutes down the road on the battery after take off before qualit= y battery time started to deteriorate. As the battery voltage fell due to = the load (and no alternator link to replenish it), electrical things (mainl= y computers first) started acting up until they could not longer run the en= gine. The injectors would not open fully, etc. Then as the voltage level f= urther decreased, the master relay which the battery held closed and which = connected the (fully functional) alternator to the rest of the electrical s= ystem - 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 t= iny toggle switch by it marked ALT BAT1 BAT2 for checking alternator batter= y 1 and battery 2 (which I no longer fly with) voltages. Down below It a c= ouple of inches and off to the right is the essential bus normal size toggl= e 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 thi= nking to check my battery voltage (which I do as a regular thing) and perha= ps distracted by something reach a bit further down and instead moved the e= ssential 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 absen= ce minded activation - either way ends with the same results {:>) Now it became clear why it didn't matter which pair of fuel injectors I tur= ned off - turning off either pair improved the situation because it slightl= y reduced the electrical load by a few amps - and the engine ran slightly b= etter 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 contin= ued to be normal during this. After I knew the cause (switch in wrong position), I decided the problem wa= s 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 ess= ential bus switch to the second battery and have the Light bulb come on. W= ho really knows. But, I have in mind a simply addition to my electrical ci= rcuit that should help in the future. I do want to state that this time when the problems started I DID switch fu= el 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 a= ctivation 3. Don't (hard not to) get overly focused on what you think is the proble= m - 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 ultima= te cause was electrical. Once the voltage got below a certain point the EC= 2 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 rel= ay released and removed the alternator from the electrical system and the p= anel 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 tha= t 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 wi= th flaps deployed!) 8. IF you change your mind about landing approach type - remember to reco= nfigure 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 C= offin 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 i= s 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 suffic= ient altitude! 10. Battery life - I had a two year old 680 odyssey battery which I mainta= in a trickle charge on whenever I'm not flying. With two EFI fuel pumps, b= oost pump, injectors, coils, EC2 and radio and just having started the engi= ne before take off - this battery lasted 55 minutes. Well, the last 5 minu= tes 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 recognize= d the need to turn them off at that time (I normally turn them off at cruis= e 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 volt= age, 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 ele= ctrical problem and not focused so much on the fuel system, I may have noti= ced the essential bus switch in the wrong position. Force yourself to exam= ine 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 priorit= y. When I decided that landing on the grass was preferable to putting a ho= le 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 - w= hat? 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://www.rotaryaviation.com/Rotorhead%20Truth.htm ________________________________ No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.339 / Virus Database: 270.12.52/2152 - Release Date: 06/03/09 = 05:53:00 --_000_C03ABB0A7362B84BB53D544B3C305E0EF65EB3B355EXVMBX0035exc_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Ed, Ben, I too have an alternator disconnect switch. Origina= lly I put it in to test for a simulated dead alternator by disconnecting it and= monitoring the battery voltage over time while driving all the electrics with engine running … I was able to live-test it one evening for about 15 minutes= . I intend to leave the switch in but it really should be a detent-type and Ed&= #8217;s idea of a diode charger is a good one. The results are as follows; note the voltage drops rapidly at first, then stabilizes for a long time, with notic= eable variations due to engine rpm: Jeff

Time                  &nb= sp;   Voltage           &n= bsp;    RPM      Comments

Pre-start       &nb= sp;      12.89           &nbs= p;         0

4-5 min             &nb= sp;   14.5            = ;            2500       Alternator IN

0         = ;            &n= bsp;        13.3            = ;            3000       Alternator OUT

1         = ;            &n= bsp;        12.38           &nbs= p;         3600

2         = ;            &n= bsp;        12.26           &nbs= p;         3600

3         = ;            &n= bsp;        12.22           &nbs= p;         3600

4         = ;            &n= bsp;        12.22           &nbs= p;         3600

5         = ;            &n= bsp;        12.21           &nbs= p;         3600

6         = ;            &n= bsp;        12.21           &nbs= p;         3600

7         = ;            &n= bsp;        12.20           &nbs= p;         3600

8         = ;            &n= bsp;        12.21           &nbs= p;         2700       Coolant @ 200F

9         = ;            &n= bsp;        12.21           &nbs= p;         2700      

10        &nbs= p;            &= nbsp;     12.20           &nbs= p;         3300       Coolant < 200F

11        &nbs= p;            &= nbsp;     12.19           &nbs= p;         3300

12        &nbs= p;            &= nbsp;     12.19           &nbs= p;         3300

13        &nbs= p;            &= nbsp;     12.19           &nbs= p;         3300       Coolant 210F

 

From: Rotary motors= in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ben Baltrusaitis
Sent: Wednesday, June 03, 2009 12:59 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Incident No. 5119

 

Ed,

Many thanks for sharing your story and excellent analysis! I = have forwarded it to our EAA group.

 

We had a similar problem when ferrying my Soob powered Kitfox= . It had an alternator on/off switch and the ferry pilot failed to turn it on af= ter refueling. It wasn't long into the flight that the tachometer quit. There w= ere red lights glowing, however, some circuits were wired to glow red when working--not the best situation. Luckily the pilot noticed the alternator switch in the "off" postion before we lost ignition. After that, = the alternator switch was always left on.

Ben

----- Original Message -----

From: Ed Anderson

Sent: 06/03/2009 12:= 35 PM

Subject: [FlyRotary] Re= : Incident No. 5119

 

Thanks, Bryan,

 

You nailed it why I do share my “most embarrassing moments” – I want to ensure that I am the sole participant in s= uch incidents (don’t want to share the fame - NOT).  I may be= the only one to make errors – but I strongly suspect that there is at lea= st one or two others out there {:>).

 

That’s why this list is so valuable – we all feel comfortable sharing our knowledge and experiences - even our goofs.  W= hile some may smugly sit back and say “well, I would have recognized the problem and solution immediately” and my hat is off to them, my only come-back is don’t be so certain – I’ve been certain that specific incidents could never happen to me and found out I was wrong.=

 

Ed

From: Rotary motors= in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Bryan Winberry
Sent: Wednesday, June 03, 2009 12:09 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Incident No. 5119

 

Ed,

Excellent report.  And like Al G, excellent airmanship!  We may have to have a call in vote, ala American Idol, to determine a “Top Gun” here.

 

Seriously, this account needs to be read by other pilots out th= ere (not just on this forum).  Many good lessons learned from someone secu= re enough to share their story, even if it alludes to an error.  Errors t= hat we all make occasionally (yeah, even you Chuck Y.)

 

I really regret not being able to attend the Texas event.<= /o:p>

 

Well done Ed,

Bryan

 

From: Rotary motors= in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anders= on
Sent: Wednesday, June 03, 2009 11:17 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Incident No. 5119

 

Certainly not trying to “TOP” Al’s door incid= ent – by the way, good airman ship and decisions, Al!  Glad the dama= ge 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 wer= e at the roundup, you will probably want to skip this repeat.<= /p>

 

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 th= e 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 t= o join up with Charlie England and Tracy.  After spending the night ther= e, 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 impro= ve..

 

Other than dodging lines of clouds and a bit of scud running, b= ut not much, I landed at Alexandria City to the southwest of Atlanta, GA to ta= ke on fuel.  I then climbed back in and fire it up and took off. 

 

I noticed that during climb-out the engine would occasionally m= iss and thought the fuel might have had a bit of water in it, but was not reall= y concerned.  So I fly on for approx another 45 minutes and had just pas= sed 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 hav= e an injector problem (like one sticking open or not opening at all).  Sinc= e 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 w= hen 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 tow= ard 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 f= uel pressure was ranging from zero to 80 psi, other electrical things were also misbehaving.  I check the voltmeter thinking perhaps the alternator ha= d died – but it showed 14 volts.  So back to the fuel system.=

 

  Finally, the engine just stops with the prop standing st= ill - like a hood ornament, I’m at around 4500-5000 MSL at this point hav= ing lost some altitude dodging a cloud (good old GPS just kept pointing to Crai= g Field).  At that time I am 7 miles out from Craig Field at 4500 msl wi= th 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 he= ar 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 sp= ell “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 n= ot when the panel goes dark. No engine gauges, no radio, nada!

 

Well not being one inclined to panic (but I seriously considere= d it for a moment {:>)), I continued toward Craig field – I mean like t= here were lots of other alternatives.  Well Once again I found myself in th= e “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 fe= lt 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 befor= e 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 t= oo close – must have been the comforting feeling of being close to safety.  This position naturally required a tighter turn and as I turn= ed I saw I was likely to miss the runway and land in the grass. So I though I ne= ed to steepen this turn further (this is called COFFIN CORNER), but fortunatel= y glanced at my airspeed indicator to see it only registering 80 MPH and my r= ate of descent (normally 400-500 feet per minute) up to over 1000 feet per minu= te. 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 st= all speed  - meaning at 80 mph you are close to a stall in a steep turn wh= ile your are not in straight and level.  So I immediately straighten out o= f 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 w= ith a sink rate twice as high as normal (and I’ve manage a few hard landi= ngs even with a normal sink rate).

 

The hardest thing to do when you are sinking at a 1000 fpm a co= uple 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 dow= n – 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 – ha= ngar which had an airplane parked in front of it.  A nice looking young wom= an 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 tim= e 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 a= nd it said the battery was dead. Mechanic put on a battery charger and announc= ed “Yep! The battery is dead”.  So we both concluded that the alternator must have failed and not being able to replenish the drain on th= e battery by all the electrical systems such as fuel pumps, injectors, igniti= on coils, etc had drained the battery. 

 

However, there were a few problems with the analysis of a faile= d alternator.  First, the low voltage warning light never came on to war= n of an alternator problem, 2nd I never notice the voltmeter showing anything other than what it should for alternator voltage – like arou= nd 14 volts.  While checking the voltage after the Mechanic had charged t= he battery, I noticed down below that the “essential bus” switch w= as in the battery rather than the alternator position, so flicked it back to t= he alternator position figuring I must have accidentally kicked it while getti= ng to some stuff in the baggage compartment of my RV-6A.

 

It was getting late and being a bit tired not to mention stress= ed, 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 wi= th 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 cha= rge it anymore.  Made sense, so we rolled the aircraft out of the hangar.  I hopped in, threw a half dozen switches and punched the star= ter button.  The engine started on the first prop blade rotation – s= o 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 f= uel 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 – en= gine 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 circui= ts of the airport – I did so and all was operating normally and so I rad= io 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 flyin= g) been in the alternator position.  The purpose of this switch is to iso= late the battery from the alternator should the alternator fail - to prevent an alternator problem from draining the battery.  So in event of an alter= nator 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 y= ou 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&nb= sp; - 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 cou= ld not longer run the engine. The injectors would not open fully, etc.  T= hen 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.&n= bsp; 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 normal= ly 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 (whic= h I do as a regular thing) and perhaps distracted by something reach a bit furt= her 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.&nbs= p; So it is either accidental or absence minded activation - either way ends w= ith the same results {:>)

 

 

Now it became clear why it didn’t matter which pair of fu= el injectors I turned off – turning off either pair improved the situati= on because it slightly reduced the electrical load by a few amps – and t= he engine ran slightly better for a few moments.  The same thing had happ= ened when turning off one of the EFI fuel pumps – but what threw me was th= e alternator voltage continued to be normal during this.

 

 

After I knew the cause (switch in wrong position), I decided th= e 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 wa= s 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 t= o throw the essential bus switch to the second battery and have the Light bul= b come on.  Who really knows.  But, I have in mind a simply additio= n to my electrical circuit that should help in the future.

 

 

I do want to state that this time when the problems started I D= ID 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.<= o:p>

 

So what are the lessons learned:

 

  1. Put EVERY critical switch on your before-takeoff Check list
  2. Perhaps pu= t 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 R= 11; consider other possibilities.  I thought it was a fuel problem (I even switched fuel tanks this time) – it turned out to be electr= ical in its root cause.
  4. While the = fuel pressure was jumping all over the place and the EGT was erratic and en= gine surging strongly indicating a fuel problem – the ultimate cause = was electrical.  Once the voltage got below a certain point the EC2 w= as still trying to pull the injectors open, but with the voltage so low i= t could not do it properly.
  5. When the b= attery voltage dropped below a certain point, the master relay released and removed the alternator from the electrical system and the panel went d= ark – even though the alternator was still working
  6. Immediatel= y turn to the nearest airfield when serious problems occur - THEN work on fix= ing them.  I only delayed for perhaps 2-3 minutes, but that could hav= e made a difference.
  7. Watch out = for Coffin Corner turn when turning base to final – airspeed really ble= eds off fast with no engine pulling you along (and especially with flaps deployed!)
  8. IF you cha= nge your mind about landing approach type - remember to reconfigure your aircraft for the last decision – I had left my flaps deployed wh= en 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 c= ome 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 li= fe – I had a two year old 680 odyssey battery which I maintain a trickle charge on whenever I’m not flying.  With two EFI fu= el pumps, boost pump, injectors, coils, EC2 and radio and just having sta= rted the engine before take off – this battery lasted 55 minutes.&nbs= p; 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 gain= ed a few more miles.  But, if I had recognized the need to turn them o= ff at that time (I normally turn them off at cruise altitude), then I wou= ld 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 earl= y on that it was an electrical problem and not focused so much on the fuel syste= m, I may have noticed the essential bus switch in the wrong position.  Forc= e yourself to examine other possible causes (easy to say – harder to do= ).

 

NEVER, NEVER forget that flying the airplane is the first and o= nly 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 r= eady 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.co= m

http://www.d= mack.net/mazda/index.html

http://www.flyrotary.com/

http://members.cox.net/rogersda/rotary/configs.htm#N494BW<= /o:p>

http://www.rot= aryaviation.com/Rotorhead%20Truth.htm

 


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