Electronic tachs

[flyingcheesehead]

Anybody have any recommendations?

Long story short, we replaced the tach in the new R182 - I had requested an EI, but we ended up with a Horizon.

The Horizon counts all time at or above 800 RPM 1-to-1... It might as well be hobbs time. Since we bill by tach time and it's something we push a lot when trying to recruit new members, that's a big downer. In addition, that means that AD's and other maintenance items come up sooner.

That said, the Horizon has some cool features. It uses signals from the mags, and so it knows when you do your mag check and shows the drop. It also alerts you when a mag is having problems. However, it only has one light of each color (red,yellow,green) and the aforementioned time problem.

EI's cutoff is 1300 RPM, though I've heard that might be configurable as well. I'm not sure if it uses the mags the way the Horizon does and whether it has the diagnostic items either. I think you have to push a button to specifically see the mag drop. But, it does have lights around the perimeter that give you a pseudo-analog display that's pretty nice too.

Any other suggestions for electronic tachs we should be looking at or features or anything else we should be considering?

 

[Brad Z]

Any other suggestions for electronic tachs we should be looking at or features or anything else we should be considering?

I'm confused, I thought you said you settled on a Horizon?

Long story short, we replaced the tach in the new R182 - I had requested an EI, but we ended up with a Horizon.

OK, maybe you haven't installed it, or are willing to swap it out.

Either way, in the grand scheme of things, the difference between the two should amount to more than .1 or .2 hours per flight unless you spend a lot of time idling. Both units are fine...I wouldn't have a strong preference for one or the other.

As far as marketing that you bill on tach time...just price the aircraft appropriately and all will be fine. Besides, with a constant speed prop, tach versus hobbs is negligable.

 

[mondtster]

I've got a Horizon tach in my plane and while I like the troubleshooting features and the hour meter it has, I don't care for digital tachs beyond that. Personally, I'd rather have an analog tach but this one was in the plane when I got it.

 

[jesse]

I prefer analog tachs, myself.

 

[flyingcheesehead]

I'm confused, I thought you said you settled on a Horizon?

No. Our MO wanted to get the plane back on line quickly, and the Horizon is what the FBO ordered. After some complaints from pilots and consideration of the other issues with having it essentially log as Hobbs, we decided to swap it out.

Either way, in the grand scheme of things, the difference between the two should amount to more than .1 or .2 hours per flight unless you spend a lot of time idling. Both units are fine...I wouldn't have a strong preference for one or the other.

I dunno, I pretty much plan on .3 on every leg being on the ground. The DA40 is flight time, not tach time, and there's a significant difference between the two on pattern/approach type flights.

As far as marketing that you bill on tach time...just price the aircraft appropriately and all will be fine.

Except that we get to all of the hour-required maintenance items a lot faster.

Besides, with a constant speed prop, tach versus hobbs is negligable.

Not really. The C/S prop allows for a higher power/lower RPM cruise than a fixed pitch prop would. You still end up with lower RPM on final approach whether or not you have a C/S prop.

 

[Marauder]

I have the EI tach and researched the Horizon. Both are driven by the mags. The EI has a nice LED background that is easy to read. The Horizon is a larger form factor than the EI. It will fit into the hole left by a standard size tach without needing to use an adapter plate.

The EI as you noted counts tach time after reaching at least 1,200 rpms. Since this is your legal replacement for an analog tach gauge, it will count tach time a bit slower than the Horizon.

If you have a vibration zone restriction on your original tach, the Horizon will light up an LED when you are in it or the yellow zone. The EI has a series of LEDs that will light up.

The EI can display the max rpm you reach during a flight, the Horizon if I remember correctly, does not. The EI also has a feature that allows you to "zero" the rpm reading so you can see the difference from your run up rpm easier. Will read something like -50 instead of 1950 (if you are using 2000 rpms for run up and see a 50 rpm drop).

Hope this helps.

 

[Marauder]

One other thing. If you plan on upgrading your MP gauge, EI sells one that can make your engine & fuel flow/pressure gauges all look the same instead of being a Frankenstein.

 

[Hiperbiper]

I had one of these in my Grumman. Worked great and matched the rest of the panel. Super easy to install.

http://www.aircraft-spruce.com/catalog/inpages/tso_tachometer.php


Chris

 

[tehmightypirate]

No. Our MO wanted to get the plane back on line quickly, and the Horizon is what the FBO ordered. After some complaints from pilots and consideration of the other issues with having it essentially log as Hobbs, we decided to swap it out.



I dunno, I pretty much plan on .3 on every leg being on the ground. The DA40 is flight time, not tach time, and there's a significant difference between the two on pattern/approach type flights.



Except that we get to all of the hour-required maintenance items a lot faster.



Not really. The C/S prop allows for a higher power/lower RPM cruise than a fixed pitch prop would. You still end up with lower RPM on final approach whether or not you have a C/S prop.

Another good reason to have your costs based on tach and have it not log during idles is safety and wear and tear on the plane. I've seen pilots taxi fast, avoid runups, and fly at max power with no thought of fuel savings because the plane was rented out at wet Hobbs time. They figured that if they were being billed for it then they were going to get their moneys worth of flying. Conversely, on dry tach I've seen people fly easier on the plane and generally not rush on the ground because they knew they weren't being billed for it.

 

[bnt83]

I prefer analog tachs, myself.

I just don't like fixing them

 

[rbridges]

Either way, in the grand scheme of things, the difference between the two should amount to more than .1 or .2 hours per flight unless you spend a lot of time idling. Both units are fine...I wouldn't have a strong preference for one or the other.

As far as marketing that you bill on tach time...just price the aircraft appropriately and all will be fine. Besides, with a constant speed prop, tach versus hobbs is negligable.

I've got an EI (I believe) in my plane, and there is very little difference in the tach and hobbs time given how many years it has been installed. But to the students and renters counting every penny, it probably is a thorn in their side.

 

[Ted]

I just don't like fixing them

Yeah, mine acts up every now and then, and it's not the tach generators. Leaves me half tempted to swap in an AuRacle or something of that sort.

Then I look at the price and figure that it's probably better to just fix what I have when it actually causes a problem.

 

[Ray Etcheverry]

I have a horizon in my Husky and a EI in my Bonanza. Now that the Husky has 1300 hrs on it my guess would be it only has about 1150 or so . I prefer the EI tach. All the old analog models I had were always off. The one I replaced the EI with was off 100 rpm.

 

[Mike I]

Another good reason to have your costs based on tach and have it not log during idles is safety and wear and tear on the plane. I've seen pilots taxi fast, avoid runups, and fly at max power with no thought of fuel savings because the plane was rented out at wet Hobbs time. They figured that if they were being billed for it then they were going to get their moneys worth of flying. Conversely, on dry tach I've seen people fly easier on the plane and generally not rush on the ground because they knew they weren't being billed for it.

"Apply Full Rental Power!"

 

[flyingcheesehead]

I had one of these in my Grumman. Worked great and matched the rest of the panel. Super easy to install.

http://www.aircraft-spruce.com/catalog/inpages/tso_tachometer.php

Interesting... A digital pretending it's an analog. What's the advantage?

 

[flyingcheesehead]

Another good reason to have your costs based on tach and have it not log during idles is safety and wear and tear on the plane. I've seen pilots taxi fast, avoid runups, and fly at max power with no thought of fuel savings because the plane was rented out at wet Hobbs time. They figured that if they were being billed for it then they were going to get their moneys worth of flying. Conversely, on dry tach I've seen people fly easier on the plane and generally not rush on the ground because they knew they weren't being billed for it.

Yep - That's part of our thinking, and part of why we bill on tach time, and part of why we'd like a different tach.

Any of you with EI's know what sort of features it has regarding mag diagnostics, if any?

 

[flyingcheesehead]

The EI also has a feature that allows you to "zero" the rpm reading so you can see the difference from your run up rpm easier. Will read something like -50 instead of 1950 (if you are using 2000 rpms for run up and see a 50 rpm drop).

Yeah, that's about the only thing I like better about the Horizon - It senses when one mag is grounded and automatically goes to the mag-drop view (i.e. -50), no button pushes necessary.

Hope this helps.

Very much, thank you!

One other thing. If you plan on upgrading your MP gauge, EI sells one that can make your engine & fuel flow/pressure gauges all look the same instead of being a Frankenstein.

Well, we have no plans to, but if it craps out while EI is still making these products, we may make it a matching set. Won't look as good as yours though, we've got the JPI fuel flow.

 

[Skylane81E]

Yep - That's part of our thinking, and part of why we bill on tach time, and part of why we'd like a different tach.

Any of you with EI's know what sort of features it has regarding mag diagnostics, if any?

None, has a mag drop feature but no diagnostics.

 

[Piloto]

Interesting... A digital pretending it's an analog. What's the advantage?

In a small single engine plane there is no advantage. But on multiengine plane where the engine to instrument panel runs can be 100ft like on a DC-6 the only way to go is with tach generators at the engine and electrical wires to the panel. The mechanical tach cable at long distances is subject to high stress and becomes unreliable to use.

José

 

[Marauder]

Well, we have no plans to, but if it craps out while EI is still making these products, we may make it a matching set. Won't look as good as yours though, we've got the JPI fuel flow.

EI has been making the same gauges since at least the 90s. The FP-5 in the picture was my first EI gauge. I bought it in 1994.

And I have a JPI as well. They share the EI transducer for fuel flow. I have redundant MP and RPM on the JPI 830.

 

[mcoflyer]

Unless i'm in a hurry...I generally set the RPM at the bottom of the green arc.

Last time I went on a long x-country I went up to 4,500 set the RPM to about 2,100rpm...leaned correctly and ended up getting about 5.5gph on a C172 with the 160hp engine. I also got 8.1 hobbs and ended with 6.4 on the tach.

 

[flyingcheesehead]

And I have a JPI as well. They share the EI transducer for fuel flow. I have redundant MP and RPM on the JPI 830.

Interesting. Do those share transducers too? I wonder if the EI MP/RPM transducers are compatible with the Insight G-series...

 

[Marauder]

Interesting. Do those share transducers too? I wonder if the EI MP/RPM transducers are compatible with the Insight G-series...

I believe since the EI rpm and MP gauges are primary replacement instruments, they have their own sensors independent of the JPI sensors. The fuel flow is not a primary instrument on my plane and can be shared.

When flying the indications between the JPI and EI are very close for RPM and MP.

 

[PilotAlan]

Interesting... A digital pretending it's an analog. What's the advantage?

1- if you have a yellow arc on your prop(as I do) the LEDs on the perimeter will be yellow for that range.

2- it gives me a 'quick glance' analog representation of rpm.

3- it give you redline feedback with a red LED.

I put an EI in a few years ago, and wouldn't change it. It. Only records above 1200 rpm, which reduces a lot of tach time for taxiing and waiting. It also gives you a flight time timer based on last takeoff.

 

[flyingcheesehead]

1- if you have a yellow arc on your prop(as I do) the LEDs on the perimeter will be yellow for that range.

2- it gives me a 'quick glance' analog representation of rpm.

3- it give you redline feedback with a red LED.

Alan,

I understand all those, they're some of the same things I like about the EI. My comment was regarding the one that was linked in the quote - It's basically an analog tach with a digital pickup.

 

[Marauder]

Alan,

I understand all those, they're some of the same things I like about the EI. My comment was regarding the one that was linked in the quote - It's basically an analog tach with a digital pickup.

The only advantage are for those folks who just love analog. Another reason is that with that digital pickup you lose that mechanical cable that can have their own issues. My mechanical cable failed and was ordered 2 times by the shop replacing it. On the second attempt the cable was too long causing damage to the internal mechanism of my gauge.

 

[SCCutler]

I( prefer an analog presentation of RPM, but have flown with the Horizon in club aircraft and note that they have their advantages as well.

What torques me no end and will likely cause me to forgo a Horizon is that, if one is removed from an aircraft, it becomes toast; the manufacturer refuses (even with an offer of money for inspection and recertification) to allow the transfer of the STC.

 

[denverpilot]

I put an EI in a few years ago, and wouldn't change it. It. Only records above 1200 rpm, which reduces a lot of tach time for taxiing and waiting. It also gives you a flight time timer based on last takeoff.

Interesting side effect... Are you doing maintenance based on tach time?

 

[jesse]

Interesting side effect... Are you doing maintenance based on tach time?

Aircraft value is somewhat linked to tach time so there is certainly some advantage to that even if it is just paperwork.

 

[denverpilot]

Aircraft value is somewhat linked to tach time so there is certainly some advantage to that even if it is just paperwork.

Agreed. I just wonder what a FSDO might say about the lost time from a non-standard digital tach reading arbitrarily chosen by the tach manufacturer, when/if reviewing maintenance logs and if a very clued in inspector noticed this tach's odd-ball behavior.

 

[PilotAlan]

Alan,

I understand all those, they're some of the same things I like about the EI. My comment was regarding the one that was linked in the quote - It's basically an analog tach with a digital pickup.

Oops, sorry, misunderstood.
I can see the attraction of a digitally-driven analog indicator (basically like everything in a car panel). I prefer the extra info, though.

 

[PilotAlan]

Agreed. I just wonder what a FSDO might say about the lost time from a non-standard digital tach reading arbitrarily chosen by the tach manufacturer, when/if reviewing maintenance logs and if a very clued in inspector noticed this tach's odd-ball behavior.

Technically, maintenance is determined by time-in-service (flight time). Big planes often have a Hobbs or similar hooked to squat switches.
In piston aircraft, we use tach as an approximation.

The EI is STCd, the FAA already signed off (EI and Horizon have different ACOs, which is why one starts at 800 and one at 1200).

And yes, maint is done off tach time, so time below 1200 rpm doesn't count toward maint. But a mechanical tach is recording really, really slow at those RPMs.

 

[flyingcheesehead]

I( prefer an analog presentation of RPM, but have flown with the Horizon in club aircraft and note that they have their advantages as well.

What torques me no end and will likely cause me to forgo a Horizon is that, if one is removed from an aircraft, it becomes toast; the manufacturer refuses (even with an offer of money for inspection and recertification) to allow the transfer of the STC.

Wow. That's evil. And it's gonna cost us a few hundred bucks too.

And, the MO has apparently decided we're going back to full analog. Woo.

 

[Greg Bockelman]

And, the MO has apparently decided we're going back to full analog. Woo.

So what does digital do that Analog won't do?

 

[flyingcheesehead]

So what does digital do that Analog won't do?

Have fewer moving parts, cost less (the EI was going to cost $170 less than the replacement analog), be more accurate, and have more features.

 

[jhausch]

Could you add an airspeed switch and a hobbs and use that for billing and maintenance?

 

[flyingcheesehead]

OBTW... The other issue with the horizon is that it's showing one value when you shut down... Let's say, 16.24 hours. Then, when you power back up and get ready to start, it shows something else, like 16.18. Yes, something LOWER.

 

[flyingcheesehead]

Could you add an airspeed switch and a hobbs and use that for billing and maintenance?

Well, we also don't want people going at "full rental power" which is part of why we bill on the tach to start with. Back to analog we go.