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Backup steam gauges

K

kboyd59

Active Member
I am installing a glass cockpit would like suggestions on what to install for backup steam gauges.

Thank You
Ken Boyd RV9A
(57KB)
 
VFR or IFR?

kboyd59 said:
I am installing a glass cockpit would like suggestions on what to install for backup steam gauges.

Thank You
Ken Boyd RV9A
(57KB)
Click to expand...

VFR: You can look out the window for backup.
IFR: Altimeter, ASI, Turn & Bank.

Kent
 
I did about the same a Chris but I used the same p/s tube's used for the Dynon . I also think the backup is an overkill but there is no penalty of over achievement. Except a little weight .
 
Min Equipment for VFR Flight

It depends on if you want to fly when your glass cockpit is down for maintenance. What is the failure rate for the glass cockpits? Are they reliable enough? I have not looked at them much since I completed my panel when they where just new.
 
what the pros do...

Both the Cirrus and the Diamond DA40 use glass cockpit, and both have "steam" altimeter, airspeed and attitude indicators as backup. Seems reasonable to me....
 
plehrke said:
What is the failure rate for the glass cockpits? Are they reliable enough?[/SIZE][/FONT]
Click to expand...

600+ hours and two years of flying with my GRT, and not a single hardware failure in all that time. Had to reload software once becasue I left the system on and it died when the battery votage dropped too low (my fault) - went down "dirty" and I reloaded from my thumb drive. Otherwise, aside from upgrading software when new features come out - no maintenance at all!:D

Paul
 
All your eggs in one basket

kboyd59 said:
I am installing a glass cockpit would like suggestions on what to install for backup steam gauges. Thank You Ken Boyd RV9A (57KB)
Click to expand...
Ken I get your question, what is the most important to back up with steam gauges (I assume both engine and flight). Of course we are not building an airliners with triple redundancy, and it would be impractical to redundantly back-up all instruments with steam. My going position is if day VFR, consider no back-up and rely on the glass 100%. What if it goes down in-flight, so what, land. My concern is being away from home (way away) and being grounded. You have a few choices, call the manufacture of your glass for an overnight replacement (if they are not closed for the weekend), make a VAF request for a loner from fellow RV'er, carry spares in your plane or last, keep on flying with out the instrument'(s), which strangely is legal in an experimental day vfr (but may not be wise). Think of your glass display'(s), processor'(s) and sensors. You can get good redundancy with an all glass config by picking the right combo of products. The only realistic "Oh No!" may be a lightning strike taking everything out or losing all electrical power. How likely? Well both I think can be avoided. If IFR is your main mission, any weather day/night, I can see being paranoid (but not so much for day VFR). If flying IFR I'd like one electric/mechanical gyro backup, a real spinning mass, not black magic and electrons. :D (Of course some one mentioned an electric/mechanical T&B or TC, which is cheaper than a electric/mechanical AI, but they're not cheap either. If you can fly partial panel IFR needle-ball and airspeed than go for it. I found practicing partial panel in RV's, in turbulence, under the hood, yaw made the T&B needle wag, making it a challenge. RV's are not C-172's. If that is you IFR back-up practice partial panel a lot. Of course many now have a wing leveler, a must for single pilot IFR in a RV in my opinion. That may save your bacon with loss of all flight instruments.)

Engine Monitors: Now a days all our eggs are in one basket: RPM, MAP, OP, OT, fuel levels....etc. Backing up any or all of the engine monitors functions is not efficient or practical. The best solution in my opinion is TWO engine monitors. It's not likely you will have dual sensors/transducers. I'm not sure if there is a practical way to share the sensors with two processors. Some brands have EFIS/Eng info on multi displays but there is only one engine info processor. If that goes down, multi tubes or not, you loose the info. I have (1) EIS4000, all eggs in one basket. If it goes down while in flight I'm not going to crash, I'll just land, using throttle/mix/prop position, eyes & ears to fly the plane. What makes sense to me is carrying a spare EIS4000 in the plane in a "spare parts kit". The EIS4000 is small, light, easily replaced on the flight-line and not too expensive. A spare in the plane is called a LRI (line replaceable item). When flying international we take a "Fly-away kit" with spare LRI's and parts. Investing in spare parts is expensive, but its cheap insurance if you worry about it. Asking Greg at GRT, he might say, its not worth it because the EIS just does not fail. The EIS4000 has proven super reliable. I'd miss fuel level, than oil pressure / temp and than RPM/MAP the most from a peace of mind standpoint, basically all the required engine/fuel instruments required for certified planes per the FAR's. However TRUE STORY, an experimental is not required to have any instruments for day VFR, ANY! BTW, the lightspeed EI, has RPM & MAP info by connecting separate little digital (volt) displays, with out a lot of extra cost or weight.


EFIS (flight instruments): To back-up by steam gauges is not practical (vacuum pump), except a few items as others suggested, the pitot/static airspeed & altitude is a good choice. The cost, weight and simplicity of these steam gauges makes it a less painless "extra". However a quality altimeter is +$600, a quality airspeed not a lot less. You can almost add a second Dynon EFIS for that. Again dual EFIS displays (and processors) or equivalent separate instruments (all electronic) is another way to go. Go all glass and stay all glass. Do you trust them or not? For day VFR, it's overkill to have redundant displays of any kind in my opinion (but to each his own). How reliable is your TV? It works day in & out year after year (for decades).

Bottom line, for day vfr, don't back up any thing and rely on the GLASS. :eek: Practice with a safety pilot flying with the instrument panel blocked from your vision (but not the safety pilot). Can you fly that way? I DO think having the EFIS and Engine Monitor should be separate or redundant (display and processor). You don't want to lose 100% of all info when its easy to separate these items. If you go with steam back-up my vote in order: airspeed, altitude, RPM, MAP (as required) and than fuel level. Personally I don't think I'd like to fly with out all my engine instruments or fuel levels for very long, unless its an emergency.
 
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With my setup (D100, D120, 496, AD II) I opted for backup ASI and Alt. ADI II can provide backup plus the 496 in battery mode can provide basic flight information with the panel page.
Curent panel pics on the blog.
Probably overkill but it all fits into the panel.
 
For VFR id say absolutely no backup. You should not need ANY instruments to safely make an airport destination if your entire panel flew out the window. It should not even be cause for concern.

For IFR in order of importance to me for EFIS failure backup:
1. Autopilot
2. 2nd independent diff. manufacturer EFIS
3. VSI
4. ASI

Best,
 
Backup steam gauges.

I would like to thank everyone for their input it never hurts to look at something from different angles. I now have several options to think about.

Ken Boyd RV9A
(57KB)reserved
 
Ken, this is really a personal comfort level thing.

I dont trust computers, so I wanted backups. I was lucky that in the case of my panel, by putting my dual GRTs side by side, I was able to install 3" instruments below the GRTs. By using a TruTrack ADI------yes, I know it is a "computer"----which is a 3 in 1 unit, I was able to get a standard "six pack" in only 4 gauges. Fit nicely under the GRTs------ you can see my panel here.

http://www.vansairforce.com/community/showthread.php?t=18921

While I agree, this is overkill, it does satisfy my "comfort level"
 
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Mike I do like the look of the three gauges along the bottom, just looks very clean. Thanks.

Ken Boyd RV9A
(57KB) reserved.
 
CAP

I fly the G1000 equipped 182's for the Civil Air Patrol. Cessna includes a backup airspeed indicator, altimeter, and attitude indicator. There's a good ol' mag compass up there, too.

Still learning stuff at 19 hours,
Steve
 
steam gauge reliability

This is one reason why I opted for steam gauges.

Seems like everybody with the glass panels feels the need to have steam gauge backup (if only ASI and ALT).

I don't see many steam gauge panels with backups. Am I missing something here?

Are steam gauges generally considered more reliable?

Also, it seems all the electronic stuff I have, no matter the cost or sophistication (computers, etc.) is ready for the trash bin in a few years or becomes obsolete (whatever that means).

One advantage I've found with gauges is you can buy them along the way (one at a time even) so you end up with a complete panel after a time without a big outlay of money. I know; I'm just tricking myself:eek:

I call it my "Instrument of the Month Club".

Dave
 
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