I would be interested in seeing the study you are talking about. Where do you get it?

On the subject of engine monitors, I tend to agree with you. Or at least, I agree that fuel savings are not enough for me to justify the cost of one (might be if I was flying around in a twin beech!).

The kind of data you are talking about is what I am interested in. Intuitively, it is obvious that having an engine monitor "could" save you a lot of money (or your butt), but it seems like it's pretty hard to put a pencil to because of the "all at once" factor. How often does "all at once" happen on average. Once every 100 hours, or once every 10,000 hours (I think the average for accidents resulting from in-flight engine failures is once every 30,000 hours, but don't quote me because that's just my vague recollection).

You say that you figure your monitor pays for itself every couple of years in maintenance savings, and that you have actually put a pencil to this. I would be interested in hearing more about that.

The 400 million hour study is the product of the fleet experience y done on the CW 3350 engines - - about 400 million engine hours, and all of that LOP in cruise at high BMEP values, compared to engines you and I fly. Towards the end of the piston airline era, they were going to 3600 hour TBO's on those engines.

As for the engine monitors, consider this, you taxi out on a time critical trip to grandma's house for Thanksgiving.

You have a rough mag.

You taxi back and tell you mechanic one of the two following statements:

1) The Left mag is rough on the front engine; or,

2) Please change the #2 lower spark plug on the front engine, it is bad.

What is going to be the delay in getting to grandma's house?

What is going to be the difference in the amount of time your mechanic spends on fixing your "rough mag" ???

Is your mechanic going to respond to 1), and say, "Hey, I have two other planes in the shop I am finishing up for guys for Thanksgiving trips, I can't get to your troubleshooting problem until tomorrow..." or is he going to say, "Sure, I can get the plug changed in about 30 minutes."

The spark plug example is just the very beginning of a long list of similar easy diagnostic "catches" that result from owning an engine monitor and then learning to understand what it is telling you.

Again, as has been pointed out, if you make a serious effort to evaluate the failure modes and effects, one quickly realizes that the person who operates ROP really needs an engine monitor more critically than does the person who operates LOP.

Regards, George

Engine Monitor Saves Money
 

Kyle:

I can offer only my experiences, but I have come to think of the modern engine monitor as an extremely important item in the panel.

It does a lot more than most pilots know, including those who already have one.

An example of how it saves money, and time. (Time is the more scarce resource.)

I was flying back to Louisiana and was making a fuel stop in Louisville, KY. When I started the descent, I felt a very slight rumble in the seat of my pants. The passenger did not notice it.

Without the engine monitor, and the knowledge of how to use it, I might have shrugged it off and pressed on, or I would have to tell the mechanic "it's a funny rumble that I can kind of feel, but I don't know where it's coming from."

Instead, when I landed, I told the mechanic that the spark plug in the number three cylinder -- the plug running off the right mag -- was going bad. I had him replace it while we had lunch, and then we headed out.

The plug was not dead -- yet -- but it was intermittent.

How many hours could have been spent troubleshooting that? I dunno, but I paid for a spark plug and an hour of shop time and suffered zero delay.

On another plane, wiithout an engine monitor, I had an "event" which trashed three cylinders. (For the sake of clarity, I was running ROP at the time.) All I felt was a rumble, but I couldn't diagnose it. Not a big deal, just a vibration. If I had been able to glance at a monitor, I would have known it was serious and could have shut that one down, or landed.

Cost? Three weeks grounded, and about $4,000. I was actually lucky. It could have resulted in the loss of the engine.

As always, it depends on the needs, the use, and the disposition of the pilot/owner. I use my planes for transporation, over mountains, at night, in solid IFR. (Not all three at the same time, though!) Downtime is a really big deal. For me, the engine monitor, and the knowledge of how to get the most out of it, gives me additional comfort, and it saves me money and time.

For others, that equation might not be the same.

Kyle:

The study was done by American Airlines and the result was a TBO extension from 800 hours to 3600 hours, by doing nothing more than stopping running the engines ROP and making sure they were all run LOP. The data was so compelling that Wright Aircraft requested the use of the data to compile, publish, and distribute a booklet on engine management entitled, "Basic Theory of Operation of the Turbo-compound Engine." It was given to every flight engineer and the methods were followed to the letter. It became known as the WAD Manual (Wright Aeronautical Division) and can be purchased from Fly Bye Knight Press.

It is an eye-openning, informative read.

WHICH INSTRUMENT
I have been following this thread, and the LOP discussion, and I see a lot of reference to JPI engine monitors. This raises a question with me. Is there a clear advantage to the JPI analyzer over the GEM analyzer, or even the Vision Micro VM1000. In fact, couldn't you completely replace the steam gages with the VM1000 panel? Would it do the job that the JPI instrument does?

Thanks.

Larry:

These are my thoughts on the issues of deciding which engine monitor to buy.

You need single digit reads on EGT and CHT for good trouble shooting and lean tests, and the ability to download the data. In my opinion, all other features pale in importance to those two.

That leads one toward the UGB-16 by EI and the EDM 700/800 series by JPI. The GEM is improving and if it now satisfies those requirements, I'd throw it into the mix. The 1000 has one big problem. It has only a 5 degree resolution which is quite limiting in many ways. I can't for the life of me figure out why they did that. As soon as they address that deficiency, I would recommend them as well.

Single digit resolution and download capability, then after that, which ever one you like for whatever reason you like it. Oh, also, it's VERY helpful to have FF info in them. Not necessary, but being able to add it later (if you decided not to get it now) would be an important feature that may make life easier and cheaper later on.

GEM, INSIGHT, JPI, ETC....
 

Larry,
I had one of the early JPI's. If I remember correctly it had only a digital read out of (1) cylinder at a time and would go thru all (12) cylinders ONE at a time. I really needed a flight engineer to observe it. When JPI went to bar grafts, lean find, oil pressure, TIT, etc. and then to the 760, both engines in one guage I bought a 760 being familar with the company and being able to talk to them if needed plus I had the Tanis cylinder heaters and they worked well with the JPI CHT probes. Mr. Riley used (2) indicators in his 337 Rockets I believe because the 760 was not available at that time. I know of guy's that have GEM, Insight, etc and are happy with there choice...
guy, the old 72 driver...

Thanks, Walter. I looked at the cost of these units, (avionix.com) and said, heck, no steam gages, VM1000 looks cool. It certainly can be primary instruments, because it is in some factory aircraft, and it just looks cool, too. Has all the stuff in one tight layout. I don't know about download, though.
to bad the JPI 900/930 can't be certified.

Larry:

** to bad the JPI 900/930 can't be certified. **

I think it's being certified now and may be available as such buy SnF. I could be mistaken on that, but I do think that's the plan. It might be worth checking on that.

I will revive this thread with a question. The last entry was in 2005. I am considering in the future of replacing my instrument clusters with either a JPI 830 or an Ultra Twin engine system. From what I can tell the JPI fits into a 3.5 inch hole and there would be one for each engine. It is capable of replacing every engine instrument on my panel. It said it uses a JPI harness which I'm assuming is every engine sensor bundle through the firewall to the instrument itself. The Ultra is like the Garmin 1000 system, square in shape and requiring a cut in the instrument panel. However, I like the fact that a single data wire goes through the firewall to a box on the firewall. The box is connected to a harness that reads all the engine sensors. I'm leaning toward the Ultra. I'm getting tire of chasing one instrument after another trying to fix or calibrate them. It may be time to look at replacing the system instead of each component. I wanted to know if anyone has these systems and if they have had any problem. I would like your opinion on which one you like. (No LOP questions).

Karl

Karl:

IMO, there is no comparison. I have flown behind both and find the Ultra system the best on the market, by far. It is much easier to read and has a much better pilot user interface. I prefer the method that Ultra uses for the alarms functions. I much prefer the installation advantages.

Thanks for your replay Walter,

Even though it might be more expensive, I'm leaning toward the Ultra system also.

Karl

Karl:

I have been a big fan of JPI's hardware and have sold many, many units for them and recommended them for more than 15 years. They build very good hardware.

With disclosure, I was deeply involved with the design and certification of the Ultra system. My A36 was used as the test aircraft and I have a LOT of time working with the designers and the FAA during the cert process. I have a LOT of time behind the instrument. I got to help tweak it for pilot interface and engine management issues and how that should display. I am biased.

BUT, IMO educated opinion the Ultra unit is without a doubt the leader in ergonomics and the readability of the data display. It's a breeze to download the data.

Thanks Walter,

Thanks for being honest about your involvement with the Ultra system. You may be the perfect person to ask this question. I plan to install an Ultra or JPI system. I am also looking at FADEC when TCM brings it to market, but I might look at a diesel conversion/FADEC power plant. If I did go from a 6 cylinder IO-360 to a 4 cylinder TD300, would changing the Ultra configuration be as simple as installing a new wiring harness to the firewall box and a display software upgrade? Are there plans to have the Ultra system and FADEC systems talk to each other since there are a lot of duplicate sensors? You might not have an answer to these questions, but I figured I'd give it a try. Thanks,

Karl

Karl:

I am not at all impressed with TCM's FADEC as it currently exists. There are some show-stoppper problems with it and it has been a dismal failure in the market place so far. I only know of one private owner who put the TCM FADEC system in their aircraft. They had it removed after about a year. That's a big statement.

If I understand the Ultra system as it stands, changing the configuration from an installed six cylinder to a four cylinder application is very simple. I would check with them directly for a specific answer.

I know that when I was involved with it, there were a lot of things built in for future use. Many things. Many, really cool things. I would suspect that having it talk with a FADEC system (when there is a FADEC system that really works) is not that big of a deal.