# Have we reached the end of the Steam Gauge era?

Discussion in 'Instruments / Avionics / Electrical System' started by jwmflying14, Jan 20, 2017.

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1. Jan 20, 2017

### Victor Bravo

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For the last 50 or 75 years at least, the fundamental mind-set in aviation has been maximum reliability AND the presence of one or more back-up systems everywhere it is possible to have them. That shouldn't go away IMHO. Anything pneumatic can have one kind of problem (vacuum pump, bugs in the pitot tube) and anything electronic can have another kind of problem (battery, bad circuit breaker).

Modern electronics have gotten a lot better in terms of reliability, but the truth is that your phone and iPad can still be hacked by some 15 year old kid 5000 miles away from wherever you are. Nowdays, there is a strong trend towards having aircraft electronics and data systems linked and networked and sharing data with ATC, etc. So there is a network connection and there is a data pathway that can eventually be cracked. So the very LAST thing that I want is for a network outage, innocent glitch, or intentional meddling to affect my navigation. "Honest, General, the little highway-in-the-sky icon told me I was on course a hundred miles away from here, and then all of a sudden it said ATTENTION Lottery Winner!!! and it wanted my credit card number!"

As much as I will always want to carry a paper chart, I absolutely love the little $75 computer tablet and the free AvAre moving map software that I fly with. They both have a place in my airplane. For a homebuilt VFR minimalist airplane (our beloved VP-21 or Flying Motorcycle) I would say that a small tablet or large phone Velcro'ed to the panel, and perhaps one or two 2 inch pneumatic instruments, would be a good compromise. Somebody should be thinking about making a (mechanical) combination airspeed and altimeter (concentric dials or split quadrants) in a 2 1/4 inch size instrument. Outer ring is non-sensitive altitude, inner ring is airspeed - or top half separate from bottom half. Sort of like a 2 in 1 combo EGT/CHT, but air operated for ALT/ASI. Ramble/Rant switch off 2. Jan 20, 2017 ### bmcj ### bmcj #### Well-Known MemberHBA Supporter Joined: Apr 10, 2007 Messages: 13,093 Likes Received: 5,017 Location: Fresno, California True, but I'm sure you would agree that in VFR conditions, the best instrument to have is the real horizon and be experienced with the sight-picture for your plane. Best of all, in VFR conditions, the real horizon has a 100% reliability rate with zero failures. As for my plane, I want my steam gauges in front of me, a glass panel to the side in case I want to reference it for something I can't get from the gauges, and in most cases, I'll never look at either one of them because I will be enjoying the sights outside. mcrae0104, Pops and rv6ejguy like this. 3. Jan 20, 2017 ### jwmflying14 ### jwmflying14 #### Well-Known Member Joined: Oct 9, 2014 Messages: 87 Likes Received: 8 Location: Tucson So, I totally get and agree with your guys points regarding simple light aircraft, 100%. In my case I am referring to a plane that could potentially be a fuel injected fairly quick VFR xc machine. I am comparing a steam gauge outfit that would require your typical 6 pack (notice, vacuum AND electrical onboard), as well as radios, intercom, transponder, and still requiring an enginemanagement panel. From what I can gather, other than the dual redundancy of vacuum/electric, the EFIS panels come out lighter, and potentially cheaper. This isnt to touch on safety features such as synthetic vision, etc. So, while steam certainly does add reliability, EFIS offers other safety parameters. That said, I'm much less concerned about an EFIS system and "hacking" than I am with my computer or phone. No 15 year old wants to hack into my aircraft to throw a pilot (lacking awareness) off course. That's a ridiculous thing to worry about. The majority of us are "no bodys" meaning no one cares enough to hack your plane maliciously. Just my 2c. Where is the used EFIS and steam guage market? I havent seen any incredible deals worth giving up warranty, etc of an original user. 4. Jan 20, 2017 ### Topaz ### Topaz #### Super ModeratorStaff Member Joined: Jul 30, 2005 Messages: 13,963 Likes Received: 5,578 Location: Orange County, California There's enough. When you specify cross-country as a primary purpose of the airplane, even VFR, might as well go glass, IMHO. I can't say about EFIS, but Aircraft Spruce has some decent deals on refurb mechanical instruments. Some, like altimeters, can still be somewhat spendy, but most of the other stuff is pretty inexpensive, in the whole scheme of things. 5. Jan 20, 2017 ### BBerson ### BBerson #### Well-Known MemberHBA Supporter Joined: Dec 16, 2007 Messages: 12,504 Likes Received: 2,529 Location: Port Townsend WA My electronic vario quit working. The mechanical vario still works. dcstrng likes this. 6. Jan 21, 2017 ### gtae07 ### gtae07 #### Well-Known Member Joined: Dec 13, 2012 Messages: 1,842 Likes Received: 1,111 Location: Georgia I've flown minimum steam and modern glass in the exact same airframe. I've posted on the matter before: http://www.homebuiltairplanes.com/forums/showthread.php?t=18038&p=213106&viewfull=1#post213106 http://www.homebuiltairplanes.com/forums/showthread.php?t=15615&p=191717&viewfull=1#post191717 http://www.homebuiltairplanes.com/forums/showthread.php?t=23326&p=292086&viewfull=1#post292086 A modern homebuilt EFIS is going to have a greater MTBF than any vacuum system, and be a lot lighter to boot. It will also be available with a dedicated backup battery. If you're still worried about losing your primary electrical system, add an e-bus and an SD-8 standby alternator in place of your vacuum pump. And go read some of Bob Nuckolls's writings on reliable electrical systems. Regarding weight, I figured out earlier (http://www.homebuiltairplanes.com/forums/showthread.php?t=23326&p=291954&viewfull=1#post291954) that a basic single-screen VFR Skyview system will weigh about 7 pounds, including backup battery and 2020-compliant ADS-B. Add four more pounds for autopilot servos (not really useful for local flying, but oh Lord they're good to have on a long cross-country). What I've described is what I've flown with in an RV-6 for the past four years. For your electrical system, find a lightweight starter and alternator and get an EarthX LiFePo battery. As noted, a properly installed EFIS will be more reliable than your vacuum instruments. For IFR I'd suggest an independent mini standby EFIS as well--if your main system kicks the bucket, do you want to fly needle-ball-airspeed, or have a full six pack with SV as your backup? The former works, yes, but if I'm in actual and my main display dies, I'm going to have enough issues to deal with already. Adding further to the workload doesn't seem like a good idea. At least on the EFIS side, there isn't much of a market yet. Those with first-generation EFISes (D10/D100 etc) have generally either kept them as backups, can't/don't want to upgrade, or just haven't done it yet. Same goes for second-gen systems (G3X, Skyview, etc). We're just now starting to see a 'half generation' of new systems (Skyview HDX) etc. roll out to the public. Your best bet is to keep a watch on VAF. Last edited: Jan 21, 2017 nucleus likes this. 7. Jan 21, 2017 ### Toobuilder ### Toobuilder #### Well-Known Member Joined: Jan 20, 2010 Messages: 4,542 Likes Received: 3,385 Location: Mojave, Ca VAF nucleus and Mark Z like this. 8. Jan 21, 2017 ### BBerson ### BBerson #### Well-Known MemberHBA Supporter Joined: Dec 16, 2007 Messages: 12,504 Likes Received: 2,529 Location: Port Townsend WA Belite has a line of very simple electronic instrumentation for ultralights, that might be affordable. 9. Jan 21, 2017 ### Mark Z ### Mark Z #### Well-Known Member Joined: Aug 29, 2012 Messages: 557 Likes Received: 282 Location: Granbury, Texas USA 0TX0 Before I'd spend a lot of$ on avionics in a "basically" one off airframe, I'd put minimal instrumentation and go fly it. You just might find out that you're not happy with what you've strapped on your butt.

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10. Jan 21, 2017

### BBerson

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Doesn't electronic stuff become obsolete in a few years and become unsupportable? Like my old laptop.
Mechanical gauges last for decades without updated software.
Most planes sit year after year and get about 10-20 hours a year (after first year of 50 -100 hours).
So a 100,000 glass panel is worth what?, after 20 years. 11. Jan 21, 2017 ### Toobuilder ### Toobuilder #### Well-Known Member Joined: Jan 20, 2010 Messages: 4,542 Likes Received: 3,385 Location: Mojave, Ca That is a legitimate concern in my mind. Some go unsuportable when the company folds, but those manufacturers still around today seem to have staying power. Dynon, for example still supports (and sells) its first products. Equally troubling is severe constriction of the steam guage repair/overhaul market. Before long its going to be like film processing... There used to be a Fotomat in every parking lot. Not today. gtae07, bmcj and Himat like this. 12. Jan 21, 2017 ### Kyle Boatright ### Kyle Boatright #### Well-Known Member Joined: Nov 12, 2012 Messages: 852 Likes Received: 474 Location: Marietta, GA You're a bit pessimistic, but your thoughts have merit. Glass panels seem to have pretty good reliability, but all of your eggs are in one basket. After a while, that basket is one out of production part away from being a boat anchor. The other issue you raised is whether the panels become obsolete. Better stuff may come to market, but the functionality of whatever you install doesn't diminish over time. So if a glass panel filled your needs when you put it in, it should still meet your needs many years later. My biggest concern with glass is that it becomes a single source of failure that can take down most of your instrumentation. Steam gauges typically fail independently, so <FAR's aside> one failure may not put you on the ground. On an EFIS, one failure can leave you stuck in BFE. I had a friend have to land away from home in his RV-10 because of a failure in a VPX fed electrical system. Topaz likes this. 13. Jan 21, 2017 ### Riggerrob ### Riggerrob #### Well-Known Member Joined: Sep 9, 2014 Messages: 1,225 Likes Received: 357 Location: Canada Good point about the difficulty in transitioning to steam guages after your EFIS fails. Struggling with a flying emergency while transitioning to half-forgotten instrument scanning skills is a bad combination. Consider that a few years after CF-18 was introduced, old RCAF pilots complained about young pilots being "HUD cripples." Young pilots were so comfortable with heads up display (fancy gunsight) cues that they forgot how to fly on tiny, back-up steam guages that were deep down near their knee. A better way is to grab the dash-top GPS moving map display out of your car. At least then you revert to a familiar map display. Two similar electronic displays (Fancy Garmin EFIS and a tablet-based back-up) make for rapid transition when one quits. Oh! And warm up/align both systems before take-off. Finally when we are comparing steam guages versus glass: let's try to keep the playing field level (cost-wise) by limiting our conversation to freshly-overhauled (by a licensed instrument shop) steam guages versus recently re-certified glass gadgets. When comparing reliability and redundancy keep in mind weaknesses/failure modes of external sensors (e.g. pitot-static tube). 14. Jan 21, 2017 ### jwmflying14 ### jwmflying14 #### Well-Known Member Joined: Oct 9, 2014 Messages: 87 Likes Received: 8 Location: Tucson All very good points guys. I also agree we talk about similar set ups. Either refurbished glass and refurbished steam guages, new glass, etc. We also have to factor that we are talking about a cost comparison. It isnt fair to say steam is cheaper and compare minimal instrumentation, to a full suite of glass. If we are talking about a normal aircraft, you would have a set up similar to say, a 172 console. Just for reference, If i do end up going with an MGL EFIS, I would have an integrated IPad pro 9.7 (which I currently fly with anyways) on the other side of the console, with built in permanent power and foreflight running. 15. Jan 21, 2017 ### dcstrng ### dcstrng #### Well-Known Member Joined: Oct 17, 2010 Messages: 913 Likes Received: 323 Location: VA or NoDak I plan on quazi-glass (MGL-FI&E1), with steam back-up with refurbished ASI, clinometer and OP, as well as compass, but no artificial horizon -- so far total cost is slightly less than1K, but I still need to aquire senders. Since I'll be LSA, daylight VFR will be the order of the day, but given how little electro-gizmos and I get along, I figure I can at least get to the ground with steam ASI; Since my ignitions are (both) points and condenser, if I have a catastrophic electrical failure at least I'll have something to gaze at (that is still alive) while I spiral down in silence.

16. Jan 22, 2017

### Mark Z

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I like both. Sorry about the inversion.

17. Jan 22, 2017

### rtfm

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Hi,
To the OP: Why go with the MGL Lite? Get the mini instead. Almost identical functionality, but smaller, and less than \$1800 AUD (even cheaper in the US).

However, I've found an even cheaper glass option. Check this out... https://afors.com/index.php?page=adview&adid=32941&imid=0

I had a guy say to me one day - what if your glass panel fails mid-flight? My answer was: So what? I'd just look out the window and fly home. I'm not planning on crossing the Atlantic.

Duncan

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18. Jan 22, 2017

### Daleandee

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Sounds about like my panel and plan. I've got the MGL Engine & Flight gauges. They work extremely well. Instead of a back up ASI I opted for a LRI (Lift Reserve Indicator). As a VFR sport pilot the horizon in always displayed in "actual reality" just above the panel. Serious attention to the position of the nose in reference to the horizon gives me excellent attitude information. onder:

Dale Williams
N319WF @ 6J2
Myunn - "daughter of Cleanex"
120 HP - 3.0 Corvair
Tail Wheel - Center Stick
Signature Finish 2200 Paint Job
138.2 hours / Status - Flying

19. Jan 22, 2017

### bmcj

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So which gauge screwed up and caused you to fly inverted?

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20. Jan 22, 2017

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