Steam Gauges - Economical and Reliable

I'm starting this thread so that newcomers to the forum can learn about alternatives to glass panels. With most RV's being flown VFR, and moving map GPS's at such a high state of developement, the newbe needs to know that there is a viable alternative to glass.

Please feel free to post your reasons for installing traditional gauges in your RV, what it cost, and if you would do it again. Vacuum systems are optional, as there are good electrically-powered heading and attitude systems available.

Glass panels are great, but they were not readily available when I was building my airplane. That said, the concern I have with multi-function glass panels is that unless you have backup gauges, your airplane may be down for a while if the MFD fails because the MFD will probably need to go back to the factory for repair.

With glass gauges, a replacement gauge is probably sitting on the shelf at ACS or some other supplier, meaning that you can be back in the air in a couple of days courtesy of the good people at UPS or FedEx.

Yes indeed, Kyle, not only is parts availability an issue, many are electing not to install analog backups (Steam Gauges), and therefore may have to complete the flight without altitude or airspeed information. Not hard if you practice and fly alot, but a no-airspeed approach might challenge the "occasional flyer".

Older generation

I have used all analogue, mainly because I don't have to actually read the instruments, where the needle points gives me all the info at a glance.

It's probably a generational thing, but I find the time it takes for me to actually read the number and interpret it on a glass panel, means I don't "scan" the panel, I have to spend more time on each individual reading.

One of the best things about building is being able to set it up the way you want it.

Cheers,
Ron Graham (F1#105, Sydney, Oz)

I find that analog gauges are easier to glance down at periodically and see what's changed, i.e., trying to hold an assigned altitude while VFR (lots of Class B transitions and the CT doesn't trim out that well). I haven't flown glass IFR (hood or otherwise), but I can imagine that when you're focused, head-down, glass would be better due to higher density of information - fewer places to look for it.

If your mission is VFR, glass should be cheaper and simpler, not to mention being better on the human interface side. We went with the steam gauge package on the totally-VFR CT for this reason. We're also looking for glass for our next airplane since it will be an IFR trainer and XC machine.

Just my $0.02.

TODR

The only "glass" in my -9 is the Airmap1000 GPS. I like round gauges. I do need to replace my Vans altimeter, however. It has a certain spot where it gets hung up and can be annoying. It has only happened two or three times in 200hrs. Replace will easy and inexpensive with very little downtime.

My next plane will have round gauges as well.

John,

Flew a plane this weekend with Dual Cheltons. Very Nice. Could not believe that I could hold it so accurate. How I did that was look at the Cheltons every now and then and the rest of the time I was looking out the window.

Save a bunch of money and go the old fashion way----Steams and l@@k out the window. I love to fly that way.
I will have all steams and Lowrance 2000c. That will upgrade my ifinder PRO (Fishing gps) that I fly with now. It is still point A to B. At least thats how I look at it.
Its also good when you take off and all you have to do is taxi out, check DG, compass and make a radio call and your GONE. No time waiting for radio,EFIS,GRTand everything else to boot up.
Man the good ole days are still fun.

If you're building a new panel, glass can actually be cheaper. Here are the other pluses I see to flying with glass:

- there are no mechanical gyros to bang around during abrupt maneuvers
- you can set limits and have the electronics visually and aurally alert you when you exceed them therefore having less of a need to stare at gauges
- tighter scan (ie, you only have one instrument to look at)
- cleaner panel (i intend to have just an efis, a radio, an autopilot head, an aoa, and a transponder on my panel). No backup gauges. I'll carry a handheld radio and GPS. If the EFIS goes blank I can get that bird down with what's left.

Just my $.02. YMMV.

jmartinez443 said:

- cleaner panel (i intend to have just an efis, a radio, an autopilot head, an aoa, and a transponder on my panel). No backup gauges. I'll carry a handheld radio and GPS. If the EFIS goes blank I can get that bird down with what's left.

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I just have to have, a backup attitude indicator, whether it's vacuum or electric. My panel is the six pac, but I'd prefer glass.............with a few backup instruments.

L.Adamson

Steam gages--NOT!

I own an Aircoupe and am building an RV-9A. There will be no steam gages in my RV, or at most altimeter and airspeed gages for IFR backup. And absolutely no vacuum pumps, ever.

Reliable?? The altimeter in my Coupe, of unknown vintage, died a few years ago and I got a refurbished United altimeter. Now it too has died and TGH wants nearly $600 to fix it. For about $700 I can get a new one...these are TSO'd of course. Non-TSO altimeters are available for less than $250 but my mech doesn't think the FAA will do a field approval.

The DG went out in my Coupe a year or two ago. Refurbed that too, it precesses more than the old one but it's legal.

Economical?? Many hundreds of dollars for refurbed TSO'd steam gages. Put steam gages in your shiny new RV and watch its resale value plummet.

Steam gages suck. We're in a new century.

rfinch said:

I own an Aircoupe and am building an RV-9A. There will be no steam gages in my RV, or at most altimeter and airspeed gages for IFR backup. And absolutely no vacuum pumps, ever.

Reliable?? The altimeter in my Coupe, of unknown vintage, died a few years ago and I got a refurbished United altimeter. Now it too has died and TGH wants nearly $600 to fix it. For about $700 I can get a new one...these are TSO'd of course. Non-TSO altimeters are available for less than $250 but my mech doesn't think the FAA will do a field approval.

The DG went out in my Coupe a year or two ago. Refurbed that too, it precesses more than the old one but it's legal.

Economical?? Many hundreds of dollars for refurbed TSO'd steam gages. Put steam gages in your shiny new RV and watch its resale value plummet.

Steam gages suck. We're in a new century.

Click to expand...

The problems you've described are more related to the age of your gauges and the fact that they are TSO'd than anything else.

How reliable will your Dynon, Blue Mountain, or Chelton EFIS be in 50 years and what do you think it'll cost to fix it? ;-)

Kyle Boatright said:

The problems you've described are more related to the age of your gauges and the fact that they are TSO'd than anything else.

How reliable will your Dynon, Blue Mountain, or Chelton EFIS be in 50 years and what do you think it'll cost to fix it? ;-)

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The costs I described are due to TSO, but not the problems. The problems are due to mechanical stuff worked on by techs in a dead-end job.

The electronic stuff doesn't get fixed. Throw it out and buy another, which by that time (5-10 years) will be way cheaper and better. But you already knew that.

Like Kyle, I finished my plane before this revolution in EFIS's.

Lots have mentioned reliability of steam gauges. My experience in 950 hours is:

HSI rebuilt after some part inside of it came loose, seemingly only due to being poorly manufactured.
HSI glideslope flag needed replacing around 100 hours.
HSI sent back after rebuild because the belt was slipping.

Electric (RC Allen) T/C is starting to whine (too many rolls I suppose...)

Altimeter, A/S, VSI, A/H all doing fine.

I have no idea how I would configure the panel if I were building today - seems like too many choices. The target is moving too quickly. Good luck to those doing so! I would definitely put some sort of glass in though.

I plan to replace the T/C when it croaks with a small Dynon, but otherwise I'll just keep things as they are.

rfinch said:

The costs I described are due to TSO, but not the problems. The problems are due to mechanical stuff worked on by techs in a dead-end job.

The electronic stuff doesn't get fixed. Throw it out and buy another, which by that time (5-10 years) will be way cheaper and better. But you already knew that.

Click to expand...

If the plan is to throw your glass panel out every 5-10 years, why wouldn't that work with mechanical stuff?

Shoot, for $50 to $400/item, you can even replace the mechanical gauges and instruments one by one when they eventually go south. Might even save a few bucks over time that way... I've got 7 years on my airplane and have spent under $200 on instrument repairs in that time. Considering that I only have about $2k invested in gauges in the first place, I figure I'm coming out ahead of the game.

Don't get me wrong, glass panels are nice, but there are less expensive ways to build a basic panel. Beyond that, there are plenty of manufacturers of steam gauges, so if the manufacturer of my CHT gauge goes out of business, there is another product that'll drop right in the hole if mine ever fails. That probably won't be true when EFIS manufacturers start falling by the wayside.

I've been round and round about making the decision of a glass panel upgrade. Last month I was ready to pull the trigger, but every time I look at the classic sports car appearance of my analog gauge cockpit, I balk.

Now I think I'll wait until somebody comes up with a HUD...

I had a straight steam gauge panel planed and even had all the gauges except for the attitude indictor and gyroscopic compass. The least expensive way to go that I could find was using a vacuum pump driven set of instruments for these last few items. Once I crunched the numbers for fairly good quality pump and instrument package I came to the conclusion that I would be way ahead money wise and better equip if I went with a Dynon EFIS and EMS combo. So I sold everything I had except for a set of three shown in the picture below that are used for redundancy.




There is method to my madness, the Airspeed, Altitude and VSI indicators are where they are for the second seat to fly by. Since the Dynons swap pages the Attitude indicator page, or for that matter any other page, can be displayed on the EMS giving the second seat a pretty good set of instruments.

jmartinez443 said:

If you're building a new panel, glass can actually be cheaper. Here are the other pluses I see to flying with glass:

- there are no mechanical gyros to bang around during abrupt maneuvers

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I agree - if you want gyros, go glass. But if you're strictly VFR, do you need gyros? Hence my idea of steam gauges for VFR airplanes.

TODR

Yukon said:

I'm starting this thread so that newcomers to the forum can learn about alternatives to glass panels.

Click to expand...

As a manufacturer of Glass panels you might think I'd advertise the one over the other. But I will not do that.
I think both have almost equal merits and the final decision is based on what the builder wants. A well equiped mechanical panel using quality instruments can be very functional and very pleasing to the eye as well.
There is absolutely nothing wrong with a VFR panel using steam. I would advocate going for an electronic AI of good quality though - vaccum stuff I think is definitely out.
When it comes to IFR and NAV glass is probably in the lead - I think few will argue that. Yes, they can fail and they do fail. But they aren't as bad as some may make out - modern glass tends to be quite tough and reliable.

It all gets down to a couple of things: What do you like ? What are you comfortable with ? What is your budget ? What do you want to do with your aircraft ?

Simply specifying the most sophisticated glass panel because everybody else is doing it may not be the right choice for your circumstances.

But if you go mechanical - yes it will cost more than many current EFIS's - buy good quality, it will reward you with a long life. Cheap gauges may only give you useless readings (Engine gauges come to mind), become inaccurate and wear out rapidly with vibration.

Rainier
CEO MGL Avionics

Kyle Boatright said:

How reliable will your Dynon, Blue Mountain, or Chelton EFIS be in 50 years and what do you think it'll cost to fix it? ;-)

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An excellent question.
Here is my answer:
In 50 years none of the parts made for any of the above instruments (and all of the ones not quoted) will be long out of manufacture. This goes for displays, processors, memories and just about anything else.
Will any of these panels last 50 years ?
Probably not.
However - things are not quite that bad - prices are tumbling so fast, an EFIS is becomming a comodity. One thing I can say for sure - in 50 years time you would not want any of the above EFIS systems and you will be more than happy to replace your U/S unit with the latest 3D virtual reality heads up display...

Rainier
CEO MGL Avionics

G'day all,

Interesting to read that so many people are building with just glass, no 'steam' backups at all!

Here in the UK (where we regularly get accused of being behind the times) it is a legal requirement both for homebuilds and the likes of Cirruses that there is a minimal traditional panel (ASI, Altimeter etc) in addition to the acres of glass, in case of electrical failure.

It would certainly concern me to fly a purely glass cockpit aircraft, having experienced power failure in the past.

Rob

This is a good discussion...

When I started my -9, I had planned to install a simple VFR panel but realized to fly safely at night I really wanted and AI.

Sometime in there I became aware of Dynon and with the low cost and rich features the switch to glass was an easy one.

Like some of the others I elected to include a steam Airspeed, altimeter, slip ball, and wet compass. After setting everything up I realized there was no need for the compass as the Garmin 496 at the top of my panel will get me home should the glass go Tango Uniform.

My AS and altimeter are mounted just to the left of the glass panel. The AS is up high, right where I look when flaring to land. I have found that I rarely look at the AS or altitude in the glass panel but for some reason always look it its slip ball.


(click to enlarge)

Steam

Glass, what glass, my plane is VFR and having steam gauges allowed me to use stuff I already had and as an added bonus no books to read on thier operation...you just look at them, I do have a KS Avionics CHT/EGT with needles though. Anyway I spend lots of time upside down anyway so the gauges are not getting looked at much anyway

works for me

Next panel

My next panel will have a Dynon D-180 centered above a standard 3 1/8 ASI, Trutrack ADI autopilot w/attitude built in, and Altimeter.

Garmin 396/SL-40/GTX-327. Backup handheld radio and GPS in the baggage compartment.

7 instruments. That's IT.

No vacuum system and no single failure OR electrical failure will keep me from getting home safely as all flight critical instruments are backed up and the Dynon and Garmin are battery backed up. The handhelds are battery already.

Robski said:

It would certainly concern me to fly a purely glass cockpit aircraft, having experienced power failure in the past.

Click to expand...

While I'm a couple of years from a decision, I'm leaning to all glass with at most an altimeter, airspeed, and wet compass gages. As for power failure, an interesting idea I heard was have a 20 amp backup alternator on the accessory case where the vacuum pump is supposed to go. The reasoning is that the battery is for starting only. If the main alternator fails, have a backup alternator for it, not a backup battery.

rong said:

I have used all analogue, mainly because I don't have to actually read the instruments, where the needle points gives me all the info at a glance.

It's probably a generational thing, but I find the time it takes for me to actually read the number and interpret it on a glass panel, means I don't "scan" the panel, I have to spend more time on each individual reading.

One of the best things about building is being able to set it up the way you want it.

Cheers,
Ron Graham (F1#105, Sydney, Oz)

Click to expand...

Remember when digital watches were all the rage and everybody had to have one?
I even had one! Well, look down at your watch and tell me if it's analog or digital. New is not always better!

Yukon said:

Remember when digital watches were all the rage and everybody had to have one?
I even had one! Well, look down at your watch and tell me if it analog or digital. New is not always better!

Click to expand...

I had a digital watch once; the only watch I've ever bought in fact. Haven't worn it (or any watch) for over 25 years- and I am an engineer. I guess that also makes me a bit of a Luddite

I find that round gauges are easier for me to interpret quickly. I flew in an Aircoupe yesterday (not an Ercoupe!). I flew it for a few minutes, from the right seat. Despite having almost no stick time for the last 6 years, I found that I adapted to the instruments in seconds. Even flying from the right seat. An RV-7 I flew in briefly last year has dual Cheltons with a backup(!) Dynon on the passenger side. I spent much of the flight trying to figure out what the displays were telling me, as the pilot narrated. Still, he obviously had them completely sorted out and needed only a glance to see what was going on.

In the end it comes down to mission. I was surprised by the costs when I started working up a spreadsheet comparing panel options. As soon as you say "gyro", glass panels start looking pretty reasonable, price-wise. I'm not at all interested in anything resembling serious IFR flying, but I do intend to use my RV-7 for traveling a lot. I'll want more than an utterly basic panel, and I'm not interested in scrounging used instruments to use in my otherwise new airplane. When I started adding up the numbers, glass doesn't cost much more if at all than steam. Especially not if I throw in any sort of electronic engine monitoring. Lots of people use and like glass; I figure if I decide to go that route I can figure it out too.

You can debate the reliability question till the cows come home. Seems to me that as much as anything it's about one's sense of aesthetics.

Except for my GPS, my -10 is all steam. Very well equipped VFR panel for $13K including electric gyros and Digitrak. If you are strictly VFR and skip the AI,DG, autopilot and have a normal number of engine gauges (unlike mine), you could do the panel for well under $6K with steam including transponder, com, GPS. More holes to drill for sure but certainly functional. The gyros are the big ticket items here.

Somma this somma that

I'm with HECILOPTER.
I'm going with the standard 6-pack, but replace the attitude ind with a Dynon D-10, and the Directional with the Trutrak ADI, then forget the vacuum system, and increase the reliability of the electrical system a bit. That's pretty close to triple redundant, and cost effective at the same time.
Acro won't damage anything, and the panel will have a nice symmetrical and somewhat traditional appearance and function, so no one will feel too out of place. (possible wife and son flying it).
Scott Emery
RV-8 200Hp

Interesting AD...

From Aviation International News:

FAA AD Affects Hundreds of Avidyne PFDs
Following a rash of reports of incorrect altitude and airspeed indications by Avidyne Entegra EXP5000 primary flight displays, the FAA yesterday issued an Airworthiness Directive requiring the addition of cockpit placards and aircraft flight manual/pilot operating handbook operating limitations until affected displays can be repaired. The AD?which affects King Airs fitted with the Alliant cockpit retrofit, Piper Meridians and several other models?identifies by serial number 487 affected PFDs that are known to have been sent to the Avidyne service center in Melbourne, Fla., for air-data system upgrades and other maintenance between November and February. The FAA said Avidyne has traced the airspeed and altitude errors to a manufacturing defect with an air-data unit assembly but so far has been unable to determine the root cause. Once it does, repairs will be made under warranty, according to an Avidyne statement. In the meantime, IFR flight with any PFD that is exhibiting the errors is prohibited starting on the AD?s effective date of April 10. According to the FAA, these errors ?could result in airspeed/altitude mismanagement or spatial disorientation of the pilot with consequent loss of airplane control, inadequate traffic separation or controlled flight into terrain.?

John Clark
RV8 N18U "Sunshine"
KSBA

Yukon said:

Remember when digital watches were all the rage and everybody had to have one?
I even had one! Well, look down at your watch and tell me if it's analog or digital. New is not always better!

Click to expand...

I'm betting behind the analog face, your watch is digital. I do have a couple of "automatics", but for reliability and accuracy, I don't think anyone is going to argue against a digital, quartz watch.

--Bill

I have a Bullova accutron purchased in 1967. It is all gears and shafts. The tuning fork is as close to solid state as it gets. Still keeps time as good as any digital. Just a heck of a lot heavier.

Ditto for a cheap Seiko kinetic watch I purchased in Bangkok in 1968.

My opinion is..

Yukon said:

I'm starting this thread so that newcomers to the forum can learn about alternatives to glass panels. With most RV's being flown VFR, and moving map GPS's at such a high.

Click to expand...

Before talking old school analog/mechanical (nothing wrong with that), one thing electronic brings to the table is the conditional alerts for all systems, oil temp, oil pressure, low fuel level, low fuel pressure, volts, CHT, EGT....etc. The conditional part is based on RPM, like low oil pressure alert is conditional on low idle RPM, the higher oil pressure limit is at normal flight RPM, avoiding nuisance alerts. You can program your own high/low limits.

Looking at accident stats, its clear pilots don't look at their gauges. Having warning of high oil / CHT temp or low oil / fuel pressure or volts is a good thing to have. Most true analog gauges are just a needle and that is it. If you don't look at it, it does not tell you anything. Having the electronics be your flight engineer is a safety thing.

This is what I have, the GRT EIS4000. A full EIS4000 system with OT, OP, FP, Tach, fuel levels, 4 x EGT, 4 x CHT, volt and even more stuff than you can shake a stick at, starts at $900. I know it does not look as classy or have "analog" emulation but it works well and totally programmable. You can add manifold pressure, amps and about a dozen other options. A central engine monitor is also going to save space and weight, and I think it adds safety.


ANALOG

Most all analog gauges are really electric gauges which is NOT old school. It's middle school.

If you want real analog, than its mechanical. Tach, MAP, oil pressure, oil temp and fuel pressure can be mechanical. Most older Cessna's and Pipers have mechanical tachs with mechanical tach cables spinning, like an old car or bicycle speedometer cables. Even Cessna and Piper have gone to electronic tachometers. Almost all cars have electronic speed-os and tachs. The display may be analog but the drive is electrical wire. Most home builder use electric tach's. They are lighter and a tach cable is a pain (heavy and costly).

Modern or new school is really just the electric senders for the electric analog gauge to a fancy microprocessor and digital display. Some digital displays can display numbers and graphics and "emulate" a sweep analog needle or vertical/horizontal bar graph reading. Bottom line it is taking something that is analog, pressure, temp or RPM and converting it to an electric voltage or one step further digitizing it.

For real old school there is nothing like classic military 3-in-1, OP, OT, FP mechanical. It would look just right in the panel of a B-17. They are more rare now or all but gone, but in the 80's you could buy them overhauled with the dial face redone, with out the radioactive iridium markings. I like iridium. Its safe if you don't lick it or hold it next to your skin; now its a no-no. No electric power needed, very accurate and built for the military. You have to routed small fuel & oil pressure lines to the gauge. There pressure is measured mechanically with a Bourdon tube. The oil temp is "mechanical" as well with a capillary tube. The "bulb" is heated and the pressure change in the capillary tube connecting the bulb and gauge makes a bourdon tube move. The bourdon tubes are linked to the needle via a gear. The nice thing, totally mechanical, very reliable and accurate. The down side is routing fuel/oil lines, albeit tiny diameter with flow restricts. The temp capillary tube can not be cut. If you want a mechanical tach and map you have to route the tach drive cable and manifold line to the gauge. That is they way it was done, old school.

The 3 in-1 gauge can still be had at spruce aircraft in an all electric version (middle school). The price has gone up 5 fold since I bough mine. I had one and loved it. It looks classic and works. It's all electric so there are not tubes routed to the gauge.

http://www.aircraftspruce.com/catalog/inpages/threeOneGauge.php

They use to be cheap, like $150, now they are $530, plus the $160 mil-spec temp sender and cannon plug. That's over $700 by the time you plumb it. For about $200 more you can get and electronic engine instrument with 20 gauge functions. The draw of the analog gauge is strong. Even though some electronic engine monitors can do a pseudo analog digital gauge, it's not the same as a needle.



CHEAP IS NO BARGIN:

There are a lot of "inexpensive" analog electric gauges (middle school) from Vans Aircraft and Westach (edited). I am not going to make a specific comment but one thing is for sure, I hate gauges that are inaccurate, unreliable or cheaply made. I am not saying any of the above are bad. Research before you buy. Also you have to find a way to placard the limits, green, yellow or red line.

I'll comment on Van's analog gauges. They look good, have the cool logo, have proper limit lines, priced right and work, but they have a reputation for occasional odd EMF or RFI issues; some builders find when you key their radio mic some gauges dance and peg (the MAP and VOLTS seem especially prone to this). Some builders do and some don't have this issue. For the money they are very inexpensive but be ready for the above issue to pop up. If you are careful routing the wires and twisting wire pairs or using shield cable, you can minimize you chance this will happen.

Consider automotive gauges: Autometer , Stewert Warner, VDO The hot rod and race car guys have a ton of gauges; typ sizes are 1.5", 2-1/16", 2-5/8" and so on, with wild styles from retro to modern. Cost is not bad and depending on brand quality if good. Check out JEGS Performance Parts or Summit racing. They even have "pyrometer" gauges that might work for EGT? You could have for sure Tach, Manifold (vacuum), oil temp, oil pressure, fuel levels, volts and amps. That is 2" x 8 gauges! Impressive! The only down side I see is the Tachs all go to at least 4,000 or 5,000 rpm, but that will work. The tachs tend to be larger 2-5/8" dia. There was even a CHTgauge I saw, but peek was 340F, a little low. This was just a quick look at one brand and one product line.



FLIGHT INSTRUMENTS

As far as flight instruments its almost the same thing, you will spend more for mechanical/analog than for glass. Vacuum is a story unto itself. Electric gyros are crazy expensive unless you go with those China made "Falcon" models. Their quality is subject to discussion and debate. I have heard they are not repairable or rebuildable. For the cost of a Dynon EFIS10A with 10 flight instruments, you will get may be one high quality 12 volt electric DG or AI gyro. High quality vacuum gyros and pumps are expensive as well, no doubt to pay for their liability insurance and the STC seal of approval.

I'm not anti-analog; I'm just cheap and want more bang for the buck. Electronics clearly gives more bang for the buck, tends to be accurate, reliable, giving good utility, saving space, weight and cost, while doing things analog can never do, like the aforementioned warnings.

For those wanting old school I say more power to you, but don't go cheap. Get high quality (which means expensive). There is nothing wrong with mechanical whirling wheels and needles but you will be unhappy with cheap gauges. Check out Mitchell Mini gauges. http://www.aircraftspruce.com/catalog/inpages/1002730.php

I'll wade in here, although much of what I wish to express has been done by previous posters.

Firstly, I don't fly an RV but rather a much older homebuilt. It came to me with a very ugly panel, populated with WWII instruments - A/S, Alt, wet compass, mechanical tach, mechanical oil temp & pressure, analog amps. That's it because that's all that's legally mandated here in Canada. Very basic VFR.

I'm a bit paranoid about inadvertent flight into IMC so I wanted to get an AI in the panel. After flying my brother's airplane with a Dynon EFIS-D10 the decision to install an EFIS was easy - it was cheaper than installing electric AI & DG. Then my mechanical gauges started to fail and my old comm acted up - the EFIS installation program was drastically accellerated as a result.

Over the course of a winter I removed the old panel (cut it out with a jigsaw - primitive, but it worked!), built a new bolt-on panel, pre-wired and installed it. The end result is a hybrid. Dynon EFIS-D100, Lowrance 2000c GPS, Icom A200 comm, GTX320A xpdr, Vans tach, oil press & oil temp, original A/S, Alt, wet compass, plus a new VSI and vacuum attitude indicator that came along cheap (and is powered by a venturi, not a vacuum pump!).

This "new" panel is, to me, the best of all worlds. I have an EFIS which provides near-IFR capability, a moving map GPS, a new comm, and a new transponder. This suite in itself is more than sufficient for piloting the aircraft in VFR and for surviving an accidental venture into clouds. The backup analog airspeed indicator is installed in the top left corner of the panel - a quick glance on short final provides excellent speed reference. The backup altimeter allows me to cross-check to ensure the EFIS agrees - a big confidence booster.

The analog engine gauges were a compromise between ancient mechanical technology that was failing and full glass technology. At least I now have electrical transducers, and new gauges, without the cost of an EMS. And since they're only 2 1/4" instruments they're sandwiched between the EFIS and center-stack GPS, making for a very tight instrument scan.

With the old panel I flew with my eyes out the window virtually all the time. Now I find myself looking at the EFIS for its more precise guidance information, but have to remind myself not to stare at it. The moving map GPS is a real safety enhancer as I no longer have to spend forever trying to find myself on a map - a quick glance at the GPS tells if I'm on course or off course.

All in all, a hybrid panel was the right way for me to go. It has provided me with a much safer airplane to fly, it allows me to spend more time keeping a lookout on long cross-countries, and it provides me with the option to further enhance safety at relatively low cost by installing the Dynon autopilot servos. All in all, there's nothing I would change in the panel if I were to do it over again.

Separation of the backup system

I am going with a true vacuum based 6-pack and some sort of EFIS. To me this covers the most areas of concern. First, analog gages are easier for me to understand at a glance. I don't want to know I am at 1202 feet AGL, I want to know that I'm about 1200 feet. Much easier to get that from an analog 'looking' system.
I also believe the more separation you have between your primary and secondary systems the better. I do not plan on a dual electrical system any more than I plan to buy two of the same EFIS systems!
This protect against software bugs, catastrophic failure of the electrical system, and vacuum pump failures.

JD, I agree with the wisdom of a combination of technologies and have both steam guages and an EFIS in my RV7. We all know how easily software based systems can hang up due to bugs with our collective experience with PCs. I have also found the electronics in my airplane is most vulnerable to moisture in the air. So far both my transponder and my EFIS have failed to function properly on cool, very humid mornings. The third thing that can effect software based tools are cosmic rays hitting the RAM and causing the memory to flip a bit. This is a little known but real issue that I have delt with in medical electronics software. The flipped bit can be totally uneventful or can render a system non fucntional. Hardened software designs can detect this event and correct for it. So, my advice is to use disimilar technologies for back up systems.
John Adams

a combination of all

I plan to put a basic Dynon into the center of my scan, and surround it with A/S, ALT., VSI, wet compass for flt instruments. Probably mechanical engine and fuel gauges as well. No vacuum driven anything. Seems like the most reliable and economic solution for basic VFR flight, with a little comfort margin built in for some VFR night flying and hopefully very infrequent MVFR. I try not to do that stuff in single engine airplanes anymore.

My primary mission will be to go screw holes in the sky!

gmcjetpilot wrote:

"CHEAP IS NO BARGIN"

"There are a lot of "inexpensive" analog electric gauges (middle school) from Vans Aircraft, Westach, UMA, Mitchell."

All my engine (except EGT/CHT) and fuel quantity gauges are Mitchell, and in 800 hours have had no problems at all. Oh, and by the way, the 2.25" Mitchell line are VDO gauges with an aircraft case. Inexpensive, yes; cheap, no. My EGT/CHT instrument is from KS Avionics. Yes, it's mechanical, too and has been flawless.

Mitchell gauges are fine, sorry

rvsxer said:

gmcjetpilot wrote:

"CHEAP IS NO BARGIN"

"There are a lot of "inexpensive" analog electric gauges (middle school) from Vans Aircraft, Westach, UMA, Mitchell."

All my engine (except EGT/CHT) and fuel quantity gauges are Mitchell, and in 800 hours have had no problems at all. Oh, and by the way, the 2.25" Mitchell line are VDO gauges with an aircraft case. Inexpensive, yes; cheap, no. My EGT/CHT instrument is from KS Avionics. Yes, it's mechanical, too and has been flawless.

Click to expand...

Mitchell is not cheap! I should have not included Mitchell, they are actually not cheap in price or build. I don't know why I included them, I like Mitchell. The only one I really had on my least preferred list was Westach. No offense to Westach lovers, just my opinion. Its just on a value, build, accuracy and reliability scale its on the bottom of my list. I deleted Mitchell off my post. Thanks for the correction. Also UMA makes OK stuff and have some experience with them. Westach works but I'm just not a fan.

Next would be Vans mostly for spotty reliability and being susceptible or RFI and weird readings. However to recommend Van's gauges, they are value priced and good looking. On the negative they have this weird RFI deal, that causes sporadic readings and some spotty reliability issues. Just check the archives. Bob N of Aeroelectric says he's looking into a fix for Vans gauge and their sporadic indications due to RFI.

Vans engine instruments

I repaired my fuel pressure gauge today, the hairspring had missed being soldered to it's anchor at one end.
I'm happy with the design of the instruments, and it looks like the quality problems are all related to assembly, and should be easy to fix.
I've got no RF issues, but I twisted all the wires to them, and I have my radios on the opposite side of my panel - there's a pic of my panel on the F1 Rocket site.

Ron (F1 #105, Sydney, Oz)