Scary Event

I've teased a little about this event and now am able to do a full report, analysis, conclusions and solutions as to what occurred. I'm going to first preface this with a few things. I am a medical helicopter pilot in AZ. (Fellow RVer Glenn Brasch is as well). We fly in very demanding conditions day and night. We work 7 days on, 7 off and alternate days/nights. I absolutely love flying at night. When flying the helicopter we are fortunate to have Night Vision Goggles to assist us. When I tell you we fly into black holes sometimes, it is hard to describe just how dark it is. I have over 800 hours of night helicopter time and over 500 hours of fixed with night time.

The aircraft is a RV7 with ECI IO360, Whirlwind 200RV propellor and dual Pmags, full IFR panel and 400 TT. The Pmags had not been updated. They were working great so I left them in. I have had 175 hours of trouble free operation on the PMags since the previous upgrade. I had 3 other previous minor events with the Pmags.

I live at Stellar Airpark in Chandler AZ (P19). I work in Buckeye AZ. It is a 15 minute flight to/from. Roughly 50 NM. Driving requires a trek across central Phoenix on I10 where 20 miles of it is under construction. We change shifts at 7:30. The drive for day shift isn't terrible because I'm going mostly against traffic on the way to work and the traffic has cleared on the way home. Best case is 1 hour of driving. Night shift is just the opposite. I've experienced drive times each way approaching 2 hours.

So, I push the plane out the back door, I'm airborne in 5 minutes, fly for 15 minutes, 5 minutes to tie down and then a 10 minute drive to our facility. We operate out of a medical center, not the airport, so I keep a car there. From the time I leave my house to arriving in the office is 40 minutes. A minimum of 20 minutes of time saved, not to mention the frustration of dealing with traffic.

I've been doing this for several months. In fact, the track line on my 496 looks like an Etcha-sketch. In the winter, no matter what, one side of the trip will be at night. The journey from my house takes me West over a major 4 lane road for the first 5 minutes. I'm flying South of the South Mountains in Phoenix.

At the end of the road, the demographics go from the City of Phoenix to Indian Reservation. I turn Northwest upon reaching an Indian Gaming Casino, toward PIR (Phoenix International Raceway.) This is about a 4-5 minute period over the darkest part of the flight. Upon reaching PIR, I check in with Goodyear tower (kgyr) to transition the South side of their airspace. They know me know and clear me as soon as they hear my tail number. Also virtually ever helicopter flight we have transitions Goodyear airspace when going to one of the Trauma Centers in Phoenix. These guys and gals are the best I've worked with. I fly this route at 2900 ft to stay clear of the Phoenix Class Bravo.

This is great flight. The lights of Phoenix extending North as far as you can see. This includes the miles of backed up traffic that I'm so glad to avoid by flying. When the moon is out the various mountain ranges are backlit giving an ominous visual of the hazards that are out there. Beautiful and frightening at the same time.

On January 27th I push out and took off at 6:30 pm. I make my West turn, climb to 2900 ft, dial in 2450 rpm and 24". The Trutrak is activated with altitude hold and a heading of 265. I hit the "peak" button on my AFS 2500 and lean to 20 degrees lean of peak. Tunes are on the XM and no traffic is showing on the 430. It is remarkably clear for January. The air is crisp and crystal clear. I can see for 50+ miles in every direction. It is dark. No moon.

Upon reaching the Casino, I dial in 295 and head for PIR. I switch frequencies from my home airport to Goodyear. As I level out on heading 295, I feel a slight miss. I look at the engine monitor and notice my CHT's climbing and the engine is starting to run rough. I quickly realize this is a mag failure and I attempt to isolate it with the start switch. No luck. As I was doing this the CHT's were climbing rapidly. I noticed number 3 was through 500 degrees and the other 3 were close. I go to full rich and turn on the boost pump.

In this area my options for an emergency landing are slim. The area is flat but there are no lights and very few roads. I look North and have a road picked out as a possibility. My next best option is the road in front of PIR if I can make it that far. Although it is dark, I know where the road is. I've driven it and know it is wide enough with no obstructions.

The CHT's continued to climb as I weigh my options. I'm now in fear the engine could quit at any time, I've lost 800 feet and I'm hoping I can get to the PIR road. I check in with Goodyear tower and tell them what is going on and Ident. They advise I'm 3 miles Southeast of PIR. I think I can make this if I need to. I tell them this may be where I'm going to have to land.

I throttle back enough to keep the plane flying and the temps come down to the mid 400's. That is good news. I again try to isolate the mag unsuccessfully. The roughness diminishes some. Oil temp is good at just above 200, oil pressure good as is fuel flow and pressure. I'm flying at 120kts and an altitude of 1000 ft agl. This is a nice deal to have a dramatically over powered plane!!!

I'm now passing by PIR and have to decide whether I can make Goodyear. I'm 5 miles out from Goodyear. I've declared an emergency and they've cleared the airspace. I'm able to get 500 feet more altitude. The closer I get to Goodyear the better because of the proximity to bigger roads if I end up short. I'm now on an extended left base for 21 and I'm over airport property. I turn to final and have the runway made. I pull the mixture and kill the engine to get some cold air moving through it. I land and luckily a taxiway is right there to clear the runway.

A couple of airport guys show up to help. One of them had built an 8 and is now building a Titan Mustang. I didn't get his name. They tow me to a tie down. I call my work Comm Center and tell them what occurred. I learn my helicopter is on their way back to Buckeye from Phoenix. They stop by, pick me up and take me to Buckeye airport where I pick up my car.

Go to Part II

I'm truly glad to hear you are OK.

first off glad you made it down with no damage to the airframe or you.

well now that brad has posted i can too. I was waiting for a second post from darwin maybe.


Darwin- what are normal cht's for your engine at peak?

what's the damage to the engine?

Scary event Part II

The next day I called Robbie Attaway, who built my ECI engine. He consulted with the engineers from ECI and they recommend a course of action that was not conducive to doing the work on the ramp. I decided to bring the plane home on a trailer. On Saturday Jan 31, myself and Mike Kerzie, (also and Airevac pilot and 7 builder in progress) went to Goodyear and pulled the wings and trailered everything home.

After getting the plane home I pulled the cowl and start the inspection. Nothing obvious. No discoloration of the cylinders, nothing sticking out, etc... Next I put the prop at TDC and check the timing of the Pmags. The left mag is right on. I turn the prop until I get a green light on the right mag. It is roughly 200 degrees out. I pulled the plugs and drain the oil. The plugs are in great shape but I replaced them anyway. (auto plugs)

Robbie comes over and bore scopes the engine. There are no visible signs of damage to the cylinders or pistons. A cold compression check shows 1 and 2 at 66/80, with 3 and 4 at 74/80. Not bad for cold and no oil.

The Pmags are removed and sent in. I consulted with Brad at emagair and gave him the scenario. Clearly the right mag failed but we don't know why. I now try to find out why I couldn't isolate the mag. It appears the ground wire to the mag was intermittent after repeated continuity and voltage checks with the ignition switch and wiring.

I decided to completely rewire the ignition switch and mags. The only wires that I left intact were the power wire to the switch and the start wire. By rewiring I eliminated connectors that I had in line for easy removal. I also ran a new ground wire from the switch to the engine block with the ground wires with each mag. Everything checked out with continuity and voltage checks. The proper operation of the switch in all positions was confirmed.

Brad at Emagair confirmed that the mag had failed and it was something in the electronics. The magnets in each unit were still intact. The mags were updated to latest in electronics and software and returned. The mags were installed and timed with the blow method. They are both "green" at TDC.

While I had thing apart, I inspected the entire fuel system and checked each line and the injectors. I had just done this 17 hours earlier during the Condition inspection but did it again.

Today everything was back together and I fired up the engine. It started on the first blade and ran smooth as silk. I ran it for 5 minutes and conducted mag checks including killing the power to each. Everything operated as designed.

I cowled up and went for a flight. The engine ran like a top. All temperatures were normal. Several in air mag checks were done without problems. I flew for 15 minute and returned. The cowl was removed and another inspection done, including a timing check. All was well.

Tomorrow I will put an hour or two on before flying to work again. I miss flying to work and have no reservations. At least with nearly a month passed it is staying light later. Now I can make the evening flight in reasonable light conditions and improving daily.

One of the things to remember during any in flight event, FLY THE AIRPLANE. This is drummed into us during our helicopter training. Do not get distracted. FLY, NAVIGATE, COMMUNICATE. Always have an out and do not get complacent.

Regarding the Pmags, I've been asked why I continue to use them. I've had some problems. Most minor and more of an inconvenience than anything. This would not have been a problem if I could have isolated the mag. I had a failure a couple of years ago where the magnet failed. I switched that mag off and flew on. The service from Brad is excellent and they are open and honest. The mags are easy to install and set up. I really like the performance and sincerely hope the latest upgrades have solved the problems. If not I will have to re-evaluate whether I will stick with them.

It seems that Ground wires can be the cause of many gremlins. This appears the culprit in my situation. At each oil change, I'll be checking the ground wires associated with the ignition system. As I noted earlier, I had a couple of connectors in line for convenience. Although the connectors didn't play a part in the event I eliminated them anyway.

In summary, this situation could have been very bad. I think I could have gotten down and walked away about anywhere in the route but possibly not without damage and potential injury. I'm not sure I would have done anything differently. A failure of a component can occur anytime. Be prepared no matter whether it is day or night. Keep your head about you and fly the plane.

It is late and I know I'm forgetting a couple of things. If anyone has any questions, feel free to ask. If my experience helps prevent a problem for someone else then the event had a positive purpose.

I'm Guessing - No Damage

I had a similar experience during an initial flight with our RV-6A when the LASAR ignition was set approximately 65 degrees ahead of the proper setting of 25 degrees BTDC (in other words Lycoming had it set to approximately 90 BTDC). At that time I did not have a cylinder head temperature gage and I only had an EGT probe in cylinder #4 exhaust pipe. The by pulling back the throttle I could bring the EGT needle back off of the upper limit peg and keep it flying. In my foolish desire to fly I stayed up longer than you flying all the way from Chino down to the test box east of French Valley and back. There was no damage to the engine. After I bought the LASAR timing tool from Van's and reset it correctly the engine performed well.

I, like everyone else that has read your post I am sure, anxiously await your trouble shooting results.

Bob Axsom

Good job flying the airplane, Darwin. Glad it all worked out without bending any aluminum.

I know you-all love those p-mags, but stuff like that should not be happening. I hope there is a convincing fix. Such an ignition failure is not acceptable.

I really appreciate those who forge the trail and cut brush.

Makes it easier for the rest of us.


Thank you.

Glad to hear everything worked out, Darwin. I'm using dual P-mags, too, so I think I'll be double-checking my ground wires at every oil change.

Several important points here:

1) Make sure that your ignition system is properly installed and can be grounded as required.

2) I will assume that this applies to any ignition system. Be prepared to switch between mags in-flight if you have a problem that may be mag related. We all do this on the ground but may be hesitant to do it while flying. Go up over an airport and try it unless it is against mag operating condition.

Good job Darwin!

Good to hear everything went OK. I realy fear that scenerio over N. AZ terain. This is the forth case of local-RV P-mags failing that I have heard of. Though the old Bendix/slic Mags fail too. Assuming 200 degrees advanced and firing of the bad mag was still in the gas stroke by then? That is what accounted for the raising temps?

Sounds like you made good decisions all the way around, I've no doubt that the engine is fine. Our brand new O-360-A1A had momentary 500+CHT event on the first flight because of inadequate cooling (we never had a engine monitor before the rebuilt engine) and it continues to run like a top 200+ hours later.

Thank God---------

Darwin, thanks for the report.

I had been curious since you posted a bit of a teaser in another thread.

Main thing, you are O.K.

Keep up the good work.

a somewhat related question

I had an occasion of some missing on climbout at night once but nothing so scary as your experience. Congrats on some excellent crisis management.

I have often wondered what degree of power loss would occur with the complete loss of one of two conventional mags. Anybody know?

Also, I have read that carrying on with one good mag and the other shut down poses no threat to the well being of the engine although I remember being taught in PPL training to minimize power settings in that scenario, though I'm not sure that makes sense. Thoughts?

steve

One mag

Running one mag effectively redards the ignition timing..Its not very effecient but but actually imposes less load on the bottom end of the engine.

Hard to see how high power setings would hurt the engine running on one mag therefore.

Frank

That's what I thought. I think I read something by John Deakin on the subject but I can't find it.

Steve

Are you talking about two-mag setup or one-mag-one-Pmag setup? How does turning one mag off retard when they both always fire at exact same place -- 25 deg btdc(referring to two-Slick setup)?

Radomir said:

Are you talking about two-mag setup or one-mag-one-Pmag setup? How does turning one mag off retard when they both always fire at exact same place -- 25 deg btdc(referring to two-Slick setup)?

Click to expand...

I would like to hear this answer also.............

Retard the Spark with One Mag?

I am not understanding how that is going to happen if you loose a mag and that mag quites functioning. The engine just keeps on running with less power. Why? Because only one spark plug is firing. The reason there are two spark plugs in a Lycoming head has to do in part with efficient propagation of flame front. There is a lot of area at the top of a 320-360 (they are both the same sized pistonand you get better combustion with two spark plugs firing instead of one. The second benefit you get is redundancy in ignition systems.

When you add one Pmag and One regular mag, you get the benefit of the hotter spark for staring from the Pmag..they should be firing at the same time...and you get the advantage of the computerized variable timing in cruise from the Pmag.

Logic would seem to lead one to the belief if one is good, two are better, but in this case it doesn't seem to work out that way.

Tom Hunter

gasman said:

I would like to hear this answer also.............

Click to expand...

With only one plug firing, the charge is ignited from one side only. This leads to the flame front spreading more slowly, and retarding the "effective" timing, ie the point at which cylinder pressure reaches a certain value.


It's why combustion chamber design has so much effect on power and efficiency in engines with only one plug.

engineerorange said:

With only one plug firing, the charge is ignited from one side only. This leads to the flame front spreading more slowly, and retarding the "effective" timing, ie the point at which cylinder pressure reaches a certain value.

Click to expand...

Exactly.

The dual plug setup is there for efficiency as well as redundancy.

This is why in a properly operating dual mag setup, you will see a drop on each mag. If the settings are correct, the drops will be the same.

Kudos to Darwin for posting all the details.

What we are missing now is a full answer from the Emag people of how the unit failed and what, if any, changes will be made. It is unclear at this point whether firmware updates (or the lack of them) played any role at all in this incident. I can only hope that they are fully investigating this and not just replacing the unit with a new one and hoping for the best.

erich

Emagair

Erich,

The mags that failed were not updated versions. I didn't send them in because they were working. I was going to wait until March when I will be gone for a week and not need my plane. They are now the updated versions and working fine.

I'll contact Brad and see if he will post the technical stuff.

Yes, I understood that from your previous posts Darwin. I was just pointing out that unless we hear more from the Emag folks, we wont know whether the lack of an updated pmag played any role in the failure. Hope you understand when I say that I hope the failure WAS due to not having them updated - that will make those of us who do have the latest update breathe a little easier.

Good job under pressure mate!

erich

What a great report

Darwin, I just wanted to thank you for taking the time and making the effort to report all this - AND to give all of us such a well thought out distillation of how a professional pilot handles this type of situation.

Very, very well done. I'm glad you got it on pavement.

erich weaver said:

Yes, I understood that from your previous posts Darwin. I was just pointing out that unless we hear more from the Emag folks, we wont know whether the lack of an updated pmag played any role in the failure. Hope you understand when I say that I hope the failure WAS due to not having them updated - that will make those of us who do have the latest update breathe a little easier.

Good job under pressure mate!

erich

Click to expand...

I would like to know what the failure was, too. I've got dual P-Mags and have sent them in recently (December) to get the latest upgrade.

erich weaver said:

Yes, I understood that from your previous posts Darwin. I was just pointing out that unless we hear more from the Emag folks, we wont know whether the lack of an updated pmag played any role in the failure. Hope you understand when I say that I hope the failure WAS due to not having them updated - that will make those of us who do have the latest update breathe a little easier.

Good job under pressure mate!

erich

Click to expand...

Erich,

I am intimately familiar with the P-mags, their software, and their operation.

There were two modes of failure, hardware and firmware.

The hardware failure modes almost exclusively had to do with the magnet retention methods used. There are four methods that I am aware of. The final solution that came out in the fall of 2008 is critical and has been reviewed and signed off on by a P.E.

The software fix was a bit more elusive. In July of 2007 E-mag Air released V27 of their firmware. Prior to this version, a number of E/P-mags had experienced issues with lost timing marks. Without getting into details, it had to do with where and how the timing mark was stored in memory. The trigger for most of the lost timing issues had to do with the installation, with Electric Bob's drawing Z33 being one of the major culprits.

The symptoms of a magnet failure could happen anywhere in flight and typically resulted in high CHT's and occasionally backfiring.

A software failure commonly happened during the power down cycle when checking the mags prior to flight. The E/P-mags would check OK, which they were until the problem E/P-mag was powered down and backup.

The pilot would line up for takeoff and get to 500 to 600 feet before realizing their CHT's were abnormally high. (BTW, this is what happened to me on my 2nd flight.)

Some wiring can also cause the lost timing, such as back driving the buss with electricity from an electric gyro that is spinning down and poor wiring practices.

Again, it is IMPERATIVE that you send your E/P-mags in for the latest updates. There is no cost, other than S&H, which is a lot better deal than any of the other ignition manufactures offer, as far as I know.

Assuming you won't have a problem because they are running fine is not a good nor safe practice. It is kind of like not changing the float on your mag when there is an AD out on them because you haven't had a problem.

As far I can tell, there has not been one failure of an E/P-mag that has had all the upgrades performed.

PS. As Darwin pointed out, he had not had the upgrades performed on his P-mags.

As far I can tell, there has not been one failure of an E/P-mag that has had all the upgrades performed.

Click to expand...

Well, if you mean firmware failures of post 2007 firmware upgrades, by my conversations and emails with E-Magair, I experienced one in Nov 2008 with about 7 hours run time on units that had been upgraded in Jan 2008. Described in my post at:

http://www.vansairforce.com/community/showthread.php?p=301180#post301180


Technically the quote above is true as I did not have the magnet (i.e. hardware) upgrade done at that time but I talked on the phone to the person that examined the magnets on my P-Mags and the day after he looked at them he told me there was nothing wrong with the magnet mounting and I would have to wait until the next week when they could look at the electronics and software. They replaced circuit boards in the failed unit and the good one I had sent back for evaluation and hardware upgrade.

Brad told me he suspected the problem was firmware related, but I don't know that an exact root cause was ever identified. Since the answer was very definitive on the magnet inspection, I do consider this to be a failure of post-2007 firmware or electronics. Don't know if there have been others and I've got nearly 20 post-failure hours on my dual P-Mags now with no further issues.
For piece of mind and ease of troubleshooting in-flight problems in the future, I'm changing to a one mag / one P-Mag setup in the next couple weekends.

Chris......

.....you just made me more madly in love with my dinosaur Slicks

Have fun,

There is a common point regardless of mag system that should be apparent and adhered to religiously.

MAINTAIN THEM.

Regular mags have issues that require periodic inspection/parts replacement/adjustment.

The incident that started this thread may not have happened if the owner had updated his PMags with the well-known potential to fail.

My Bendix mag impulse coupler problem may have been my failure to have it inspected in time to identify and repair a failing part.

pierre smith said:

.....you just made me more madly in love with my dinosaur Slicks

Have fun,

Click to expand...

Although our -4 has one mag and one Light Speed ignition, I agree with your sentiment.

I think our set up is the way to go, as you get the best of both worlds. I?d much rather have the reliability of the one mag over the slight increase in performance two electronic ignitions provide.

N941WR said:

PS. As Darwin pointed out, he had not had the upgrades performed on his P-mags.

Click to expand...

Yes, ok, we have established this, I understand, enough on this point (please).

Your summation of past known hardware/firmware failure modes also matches my understanding. That still leaves open the question of whether the particular failure mode that Darwin experienced would have been avoided if the updates had been made or whether it is a NEW type of failure that could potentially happen to all of us emag/pmag owners, updates or not. We will only know this if Emag does the analysis and shares the results with us.

erich

Is the vision flawed

N941WR said:

Erich,

As far I can tell, there has not been one failure of an E/P-mag that has had all the upgrades performed.

PS. As Darwin pointed out, he had not had the upgrades performed on his P-mags.

Click to expand...

For years I've been watching the Pmag saga unfold. Always the Pmag is one modification, one update, one repair away from being a reliable product. But predictions of the new dawn of success seem always to be premature. It's getting to be a bit like the ongoing stockmarket crisis.....things just keep getting worse and, despite the sporadic bursts of optimism, the truth is that no-one really knows where the bottom is.

My major concern with the Pmag system has always been that integrated circuits really hate 3 things.....heat, vibration, and moisture. And attaching an IC directly to a Lycoming provides lots of all three in perpetuity. It may just be an unsustainable environment. The technological vision may be flawed.

The Lightspeed installation guide calls for their CD Ignition Module (the brain) to be located in the cabin area. It is relevant that early installers of Lightspeed EIs who persisted in installing the module firewall forward were often rewarded with malfunctions. I doubt any knowledgeable builder adopts that practice anymore.

I truly hope that the Pmag survives and becomes a roaring success. Like so many others, I love the basic principle. But having said that I can see that it might be an uphill battle to get ICs to perform reliably for extended periods of time in such a harsh environment.

Captain Avgas said:

For years I've been watching the Pmag saga unfold. Always the Pmag is one modification, one update, one repair away from being a reliable product. But predictions of the new dawn of success seem always to be premature. It's getting to be a bit like the ongoing stockmarket crisis.....things just keep getting worse and, despite the sporadic bursts of optimism, the truth is that no-one really knows where the bottom is.

My major concern with the Pmag system has always been that integrated circuits really hate 3 things.....heat, vibration, and moisture. And attaching an IC directly to a Lycoming provides lots of all three in perpetuity. It may just be an unsustainable environment. The technological vision may be flawed.

The Lightspeed installation guide calls for their CD Ignition Module (the brain) to be located in the cabin area. It is relevant that early installers of Lightspeed EIs who persisted in installing the module firewall forward were often rewarded with malfunctions. I doubt any knowledgeable builder adopts that practice anymore.

I truly hope that the Pmag survives and becomes a roaring success. Like so many others, I love the basic principle. But having said that I can see that it might be an uphill battle to get ICs to perform reliably for extended periods of time in such a harsh environment.

Click to expand...

I think it's worth noting that almost all of the issues with Emagair's products have been related to firmware. The only exception, that I'm aware of, is the sensor mount issue of late. I agree that circuits don't like heat, moisture or vibration, but from what I can tell, that has never been the cause of a P-Mag failure (specifically referring to the circuit board).

I'm curious to see if Darwin's problem was, indeed, firmware related. If so, they very well may have the worst behind them.

Fault Analysis

How about some actual data from Emagair rather than speculation. As long as they have been in business they should have some data regarding their units failures and what the causes were and what they have done to eliminate "issues" with the Pmag.

I think it is fine for many users to come to their defense, but we all have only a limited view of the "issues" with the product.

I'd like to add one Pmag to my plane and replace one Slick and I am sure others would as well. Until I have more definitive information rather than speculation, I am not inclined to trade reliability for uncertainty.

Apparently some of you who have written in on this thread have a close relationship with the folks at Pmag. How about seeing if they would be willing to give us a run down on the current state of the product. On the TruTrak thread I see the technician using that thread to keep folks up to date on their products. And I see Beta users postings on GRT which I have found as I am sure many others to be of great benefit.

Tom Hunter

They are friends of mine

I know Brad a Tom personally. They live and work within 10 miles of my house. I have sat around and discussed E/Pmag issues with them at length. Believe me, they are trying to provide the best possible product but it is difficult to foresee every problem. You will not believe what some people will do. Consequently, you end up with a lot of updates. Additionally, Tom, who writes the firmware, is constantly trying to improve the performance of the Pmags. These guys have come a long way since I first met them in '05. They started in a shed behind Tom's house and have grown into a large facility in Azle Texas. They recently hired a tech to help them. For a long time it was just Tom and Brad doing it all. I've asked them many times to get on forums like this and defend their product or at least explain the problems. They will not do it. They have seen other manufactures get caught up in online forums and they don't want to be like that. In fact, they don't even read these forums. Every once an awhile when I think they are getting beat up online, I stop by their shop and talk about it. They usually have a reasonable explaination. I always offer to defend them online but they invariably decline my offer. They are focused on improving their product and refuse to get involved online. I personally think they should but in actuality they don't have the time. I know it's hard to believe but there are a lot of forums out there in addition to Vansairforce.net. It would take way more time than they have. So, bottom line (BL for the fighter guys) they are not going to answer questions here. If there are some really focused and important questions that you want answered, let me know and I'll stop by and ask them for you. Can't promise an answer but I'll ask.

cguarino said:

If there are some really focused and important questions that you want answered, let me know and I'll stop by and ask them for you. Can't promise an answer but I'll ask.

Click to expand...

OK, Im game. Question 1: Has Emag Ignitions done a failure analysis on Darwin Barrie's pmag unit? If so, what was the root cause, and what actions need to be taken to avoid this same type of failure in other units? If not, why not?

Question 2: Same questions as above, but regarding Chris' failure described above in post 27. Sorry, dont know Chris' last name - perhaps he can chime in to improve our chances here.

thanks

erich

OK, Im game. Question 1: Has Emag Ignitions done a failure analysis on Darwin Barrie's pmag unit? If so, what was the root cause, and what actions need to be taken to avoid this same type of failure in other units? If not, why not?

Question 2: Same questions as above, but regarding Chris' failure described above in post 27. Sorry, dont know Chris' last name - perhaps he can chime in to improve our chances here.

Click to expand...

Erich - my last name is Hand (full name is in my profile, just not my sig block), but I'm not sure they held onto my old parts or did a full root cause analysis. If a root cause was identified, it was not reported to me.
I did ask similar questions of E-magair after the first explanation I got that the suspected problem was the firmware. A couple weeks after that first report, I asked the following questions:

Do you have any better description of what you think went wrong? When you say firmware related, are you saying the software was somehow corrupted during operation, resulting in the seemingly random firing? If so, do you suspect a hardware failure that affected the installed firmware, or a coding issue?

Were you able to recreate the failure during bench testing?

Click to expand...

The response I got didn't answer the questions and did not include the initial mechanical inspection results I got over the phone. Response was a summary of the bench report on what they replaced (PCB, shaft, and stator) with statement that from replacement of those parts there were several different causes that "might" have caused my problem: firmware problem, ferrous debris attracted by the magnets, play in the shaft, and potential that the magnets came loose.

Loose magnets as the cause was eliminated at the time of their initial inspection when I was told on the phone that the magnets were good so they needed to do further troubleshooting the following week on the electronics and software. Loose/shifted magnets also wouldn't explain the random tach indication that was instantaneously jumping to various numers ranging from 0 to 6000 rpm during the failure. Waiting for the electronics/software evaluation delayed return of my units since it was not just an issue of doing the magnet SB and returning them. I was happy with the customer service in getting the updates/repairs done, but it kept me grounded for 3 weeks with shipping time included when it wasn't just the SB fix that was needed.
No reports of ferrous debris or play in the shaft were reported on that initial inspection either. The unit only had 7 hours on it and going from "green" to "red" when moving the prop off the timing mark was equally sensitive for both P-Mags when checked before first flight and on subsequent fwf checks, so I don't think play in the shaft was an issue.

That only leaves software or electronics failure, consistent with Brad's first email to me, but I don't know if my failed hardware/software was evaluated to the point of root cause. The repaired units have been working well and by replacing one of them with a Slick, I'm comfortable I can quickly isolate the problem if I experience a similar failure.


Pierre - I'm glad I could help maintain your love of the Slicks I'm only half way there...keeping one P-Mag to pair with my new Slick, at least for now.

thanks for the update Chris. The responses you describe from Emag are similar to the type of explanations I have gotten before. I worry that in at least some cases the root cause has not been investigated - they have simply replaced the component that failed. Hope that proves not to be the case and Charlie can get back to us with some definitive answers.

erich

A little update

My mag failure was related to the electronics. Brad said the firmware before the latest upgrades would occasionally cause the timing to go bad with a power interruption. I don't remember the exact wording he told me so don't hold me to it. Extreme detail wasn't discussed. If I had a bad ground as I suspect, this makes sense.

He related the newest upgrades have cured that problem. We also discussed what could be causing some of the problems. He said many people chose to do their own thing when wiring and not follow the instructions. It is really unknown how many problems were builder induced.

I've now got roughly 5 hours on the upgraded mags. This morning we did a compression check after I got home from work and got the following numbers. #1 74/80 #2 70/80 #3 74/80 #4 72/80. Further there has been no oil consumption.

I think that if you have any questions regarding the specifics of the electronics and the failures, give Brad a call. He will be honest and forthright with you.

I sincerely hope the mags continue to work and the bugs are worked out. For those who are preparing to use Pmags, please wire them per the instruction and not try some alternative method of wiring.

Darwin,

Good to hear the engine is going to be OK.

You are on my list as as soon as we are ready to ship the E/P-mag monitor I will let you know.

First, this going to be a long post but I?m going to try to give everyone some SA and background on Emag. I have been watching this forum and noticing a growing frustration about the answers received / not received from Emag concerning ignition failures. Darwin?s being the most recently discussed. So, I stopped by Emag on my way home from work yesterday and talked to Tom and Brad for about an hour and half about this. While talking to them, I realized that there is probably an inconsistency between what people expect and what is reality. Now this is all 100% my opinion and not Brad or Tom?s words. For those of you that don't know, Emag is a two man show. Tom is an ex submariner and has a brain that weighs in at about 22 lbs. Brad is the business man of the operation and together they conceived the idea, and hand built each and every E/Pmag out there. They finally hired one employee within the last year. They tried their best to turn out a perfect product right off the bat but we should?ve all expected that there would be growing pains. Tom did his best to account for all the variables out there but there is just no way to do that. So they started selling their product knowing that they would make regular updates to fix problems as they discovered them. We, as experimental airplane builders should understand this. If we were to demand a perfect product from the beginning we never would have gotten anything. The reason we still have mags on airplanes is not because they are reliable. I've had more mag failures than Pmag failures. No, it is because the certification process is too expensive compared to the available market. Additionally, you will never see a EI like a Pmag certified because every time you need to do an update you would have to recertify the EI. This would be cost prohibitive.
Now for the issue about failure modes. Brad and Tom receive a lot of ignitions back for service and frankly a lot of the time there is nothing wrong with the EI. It usually ends up being a wiring problem or even something completely unrelated to the ignition. They had one the other day that turned out to be a blocked fuel line. So they are spending a lot of time troubleshooting perfectly good ignitions and as I said before, they are only 3 dudes doing all this. If the problem is obvious they will find it. If it is not, they will just change parts, perform the updates, check out the EI and ship it back to the customer. Unless they see a trend like they did with the magnet attachment, they don't have the time to chase every failure or suspected failure to ground. In Darwin's case he didn't have the updates that would have prevented a lost timing episode and he had a known wiring problem. So Emag wrote it off as most probably a failure mode that they have already fixed in their updates. Tom explained how the lost timing thing was happening in great detail and the latest updates make that failure mode impossible. In fact, the technique of timing the Pmag to the "natural timing position" instead of blowing in the tube is no longer valid. It does absolutely nothing for you. That said, when they see a trend they react. When the magnet issue came up they halted production and immediately went to work on a fix and issued a SB. So they are acting responsibly. I believe that the Pmag is maturing into a great product. It looks like the big problems are behind them. A lot of credit goes out to the pilots that have been flying these EIs. They did the operational testing that improved the Pmag to ot's current state. We just need to make sure we keep our E/Pmags updated. Just because it is running fine is not a good reason to skip the update. There are known problems in the earlier firmware versions that can bite you anytime with absolutely no warning.
Another thing I?ve noticed is that some people seem to have problems with E/Pmags and others have few or none. I think this is related to wiring and or procedures. If you are having a lot of trouble with these EIs , I?d look real hard at your setup and your procedures. I have dual Pmags wired through a pull type breaker for power and a SPST switch for each P lead. This has worked well for me .
If anyone wants more info, please ask. As I said before, Brad and Tom are not going to join this forum. So, I'm the best you're going to get and I?ll do my best to get you the info you need. If you read this entire post, thanks. Fly safe.

325 hours on PMags - issues earlier, but I second getting the updates done!

I had a number of issues earlier with my PMags. After numerous problems and long discussions with Brad through the process, I had to conclude my installation without cooling blast tubes (which were recommended, but not required, at the time) was the root cause of my problems. When they got sent back each time, their internal temp sensors showed exposure to higher than designed temperatures (I don't recall the numbers, but it was way above what they designed for).
I added the blast tubes after I returned from Oshkosh in 2007 (had a series of problems enroute) and haven't had any timing problems since. ( I kept an older software version in the left ignition which occasionally didn't initialize on startup and required a restart after the mag check killed the engine. I thought that it had worked through the other problems so it was worth keeping in spite of the initialization problems).
I got the latest updates on both ignitions last fall and they modified the magnet mounts, even though my units weren't subject to the service bulletin. They also came back with a temp sensor on the outside which turns black if it gets to (I think) 95C. I can see the one from the oil door, so I can check it on preflight. So far, all has been well, but it hasn't been hot yet. I did do a series of flights last week, taking a lap around the pattern, then shutting down for 5 min on the ramp. I did this 5 times on a 70 degree day, and nothing got hot and everything ran fine.

My issues all involved multiple flights on hot days, and I've since flown on a 100 degree day from OAK to SMF to O61 with no problems except for me roasting in the cockpit.

I am pretty sure EMag requires cooling tubes now (I certainly recommend them based on my experience).

I have to concur that EMag's support has been outstanding. Our issues enroute to OSH on '07 had us calling Brad on his cell at OSH and resulted in his wife going to the shop and overnighting 2 replacements to us in Kansas City. Also, the updates have been fast and free (I paid for shipping).

I have kept the faith and love the efficiency I'm getting with the ignitions.


Seb Trost
RV-7A 325 hours
Boulder City, NV (61B)

cguarino said:

In Darwin's case he didn't have the updates that would have prevented a lost timing episode and he had a known wiring problem. So Emag wrote it off as most probably a failure mode that they have already fixed in their updates.

Click to expand...

Charlie: thanks for looking into this. Im still a bit troubled by this however. Perhaps Im reading too much into it, but Darwin previously posted that his understanding from Emag was that his problem was in the electronics - I took that to mean a hardware/circuitboard problem rather than something in the firmware that could be fixed by an update. Are you saying this is not the case? (Darwin, please chime in on this as well if I am mistating things). Also, my understanding of the "wiring problem" was that he may have had a bad ground on his switch. While that would account for his apparent inability to isolate and disable the bad pmag, it has absolutely nothing to do with the pmag losing its timing. Losing timing and having a bad ground make a very bad pair, but I see them as being unrelated.

Any insights specific to Chris Hand's problem which occurred WITH the current updates?

thanks
erich

Pmag 101

I didn't give the exact reason for Darwin's failure because Brad and Tom don't know. If his problem was caused by old firmware, there would be no way to prove it was the problem. My understanding was that his Pmag ran fine on the test bench which leads me to believe it could be the old firmware. Emag may have swapped out his PCB as a precaution. They didn't tell me anything about a bad part. As I said in my previous post, they can’t chase every failure / suspected failure to ground. Now as for why the wiring could have been a problem. There are two processors in a Pmag. One is the main processor and the other processes the crank position. In the old firmware, on boot up the main processor powered up and loaded the tables and code. It then sent the timing offset to the crank position processor. This offset was the difference between the "natural timing" of the Pmag and the position when you blew in the tube to set the timing. Once this was done the crank position processor reported the crank position to the main processor including the offset. In the case of a power dip, the main processor is well protected and has logic that causes it to reboot and reload the tables and code. However the crank position processor does not have this same protection and it would occasionally end up with a corrupt offset due to the power dip. This was actually a deficiency in the chip. Tom worked with the chip manufacturer to get the same protection that the main processor has, built into the crank position processor. To fix this problem in the Pmag, Tom rewrote the firmware. Now, when the power dips, the main processor controls the power to the crank position processor and causes it to cycle power and reboot. Additionally, the main processor no longer sends the offset to the crank position processor. The main processor gets the raw crank position from the crank position processor and applies the offset to this raw position. Once set, this offset cannot change until reset. That is why timing the Pmag to the “natural timing” doesn’t do anything for you. Since this change, I don’t think there have been any lost timing events due to firmware / power dips. Now back to the wire, a bad ground can cause a power dip. I don’t know where Darwin’s ground problem was located but it could have been a player in this scenario. I hope this helps. One more thing, Brad and Tom didn’t mention a new series Pmag to me. I don’t think the sale discussed in the other thread is a clearance sale. I think Emag is doing ok. They are still growing.

edit: Brad didn't remember Chris Hand's failure by name and I didn't have the details to help remind him. So I have no info on that one.

Two Emag since 2013, 650h.

I've got flying with two Emags V. 114, in a RV-7A, with a Superior XIO_360 engine.
During this time I've got some problems of loosing timing, a few. But, not concerned. Another big problem, was my fault. I've turned the engine without the cables and sparks plugs on. It cost me some money, I've to replace two coils.
Even them, I'm pretty happy with both ignitions.

jcmm said:

I've got flying with two Emags V. 114, in a RV-7A, with a Superior XIO_360 engine.
During this time I've got some problems of loosing timing, a few. But, not concerned. Another big problem, was my fault. I've turned the engine without the cables and sparks plugs on. It cost me some money, I've to replace two coils.
Even them, I'm pretty happy with both ignitions.

Click to expand...

Oi JC, how do you have your pmags wired? My understanding is that the issue of losing timing was solved in 114 and if they are wired so that they are not in "maintenance" mode. Obrigado!

Failure

jcmm said:

<snip>
Another big problem, was my fault. I've turned the engine without the cables and sparks plugs on. It cost me some money, I've to replace two coils.
<snip>

Click to expand...

What does this mean?

wirejock said:

What does this mean?

Click to expand...

The manual has this text:

CAUTION: Do NOT strike or apply significant inward force to the ignition shaft. Doing so could damage or misalign the position sensor.

Operating the ignition without all connections 1) power, 2) ground, 3) p-lead, 4) plug wires and plugs [***IMPORTANT***] with each plug grounded to the engine case, can result in damage to the ignition and/or cause an electrical shock to the installer.

Please resist the temptation to do a quick (incomplete) hook-up so you can watch the ignition spark or make the LED light up.

Firing the ignition without all spark plugs connected (and properly grounded) can damage the unit, and void your warranty.

Click to expand...

Could be that not having the plugs connected could damage the coils?

I’m sure it’s a stupid question but how do we make updates to the pmag? Does it have to be pulled and shipped in?

Whitman said:

I’m sure it’s a stupid question but how do we make updates to the pmag? Does it have to be pulled and shipped in?

Click to expand...

My experience is that you have to ship it back to the factory. Not sure how they update or if this could become a field updatable process. So far, I've only needed to do it once in 11 years of ownership, and they have been on this version (114) for several years. 114 had an important update that seems to have solved the problem of unexpected timing changes.