Wardo said:
going glass but insist on backup adi, alt, as.
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The most reliable backup for ADI, Alt, ASI would be more glass - a Dynon D-10A gives you all of these, will tolerate Acro indefinitely, and probably cost less than the vacuum pump, regs, tubing, and instruments.

Paul
 
Are you looking for the cheapest solution, the lightest solution or the most redundant solution?

If you want cheap, go with the vacuum pump.

If you want light, go with no vacuum pump.

If you reliable redundancy, go with no vacuum pump and add either a second battery or a standby alternator mounted where the vacuum pump would have been. This level of redundancy is only needed if you fly IFR or have an engine that absolutely requires electricity to keep running.
 
To date (in planes other than my RV's) I've had two vacuum pump failures, one on a missed approach climb-out. With all the electronic options that are far more accurate and reliable why would anyone want an arcane vacuum system in their plane. The electronic solutions are lighter and in a few cases where simplicity is desired, equal in price. There is a reason vacuum pumps have a plastic gear on them....they are designed to fail at their convenience not yours.
 
Vaccum pump vs glass

Wardo,

I decided to go with the Dynon D10A as my "standby gyro" to supplement the FD 180 primary display, with the blessing of Mel Asberry. The neat thing is that I can now display my flight instruments and HSI on the FD180, and display the engine monitoring system (EMS) on the D10A. If I really need the standby gyro, one push of the button brings back the primary flight display on the D10A, with the familiarity of the Dynon EFIS. For backup of the electrical system, the FD180, D10A and Garmin 396 all have internal batteries, eliminating the need for an E-bus or second alternator.

Craig
 
Some other thoughts

No "Glass" system currently in existence will be current and supported without upgrades 10 years from now.

Vacuum system components based on physics not software or GPS or any other man made facilitating system will continue to work until wear out and will be failed unit replaceable beyond the life of your airplane.

The vacuum system will continue to provide attitude and direction information after a complete electrical failure due to power source or circuits.

Vacuum systems are continuous based and failures tend to be decaying in nature not subject to step function failures due to bit flips, bit failures, oscillators, voltage levels (logic and power), etc. of digital systems.

Vacuum system instruments are distributed and loosing one does not take down the whole system.

Vacuum systems are cheap.

Vacuum system components from one manufacturer are interchangeable with like components from other manufacturers.

Vacuum system service can be performed by a wide range of facilities.

A functioning vacuum system makes the airplane independent of any developmental problems - it is fully matured.

Each vacuum system instrument has a dedicated simple function that requires no thought or focus for use.

Bob Axsom
 
Seriously

You can put a venturi on the side of your fuselage and your vacuum instruments will still be working after an engine failure! Seriously, vacuum pumps are heavy, cantankerous machines that have no business being used in the modern age. They belong in the same junk pile as carburetors, magnetos, mechanical gyros, gascolators and paper maps and charts; none of which can be found on my IFR airplane and I'm a 65 year old geezer.
On the other hand, you are entitled to your opinion and it's your airplane, so do what makes you happy and comfortable (and dated).:rolleyes:

(flame suit donned.)
 
ronschreck said:
You can put a venturi on the side of your fuselage and your vacuum instruments will still be working after an engine failure! Seriously, vacuum pumps are heavy, cantankerous machines that have no business being used in the modern age. They belong in the same junk pile as carburetors, magnetos, mechanical gyros, gascolators and paper maps and charts; none of which can be found on my IFR airplane and I'm a 65 year old geezer.
On the other hand, you are entitled to your opinion and it's your airplane, so do what makes you happy and comfortable (and dated).:rolleyes:
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I'm only 60, so I'll keep my carb, gascolator, magnetos..........and probably even the vacuum pump, when I install a SkyView or something along those lines. I still like the idea of systems not totally dependent on the aircraft's electrical system. Even with backups. I do believe in the modern GPS , over the ancient nav system, though. Perhaps, in five more years, I'll change my mind.. :)

L.Adamson --- RV6A/ Garmin 696 with battery backup
 
Wardo said:
well its decision time. vacuum pump or no vacuum pump, that is the question.
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With all the great digital options available...this is still a question?

If you go vacuum, might as well put an ADF in it, too. ;)
 
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No updates needed

I use a D10-A (with internal battery back up) as my primary ADI. Has not hi-cupped in 200 hrs. As a simple attitude indicator I do not think it will ever be necessary to update the software. Don't think that it is GPS dependent either.

Can't think of a more simple, more reliable, lighter, more dependable, less maintenance attitude indicator. Adding up the cost of a vacuum pump and ADI, figure in replacement every two years, and I figure you can probably add "no cheaper" to the list above too.

I've got steam AS, Alt, VSI, with a Trutrak Pictorial Pilot also. Being stuck without an adequate attitude (or heading) reference is so far down on my risk radar as to be a non issue.

FWIW, fly on!
 
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Money pit

Minimum cost for new vacuum system:
1) New pump = $380
2) Pump fittings = $ 70
3) Regulator = $195
4) Central filter = $ 30
5) Hose = $ 20
6) Worlds cheapest DG = $530
7) Worlds cheapest AH = $530
8) Hose fittings = $ 20
9) Vacuum gage = $ 90
Note: These gyros will break. The pump can go any time.

Total = $1865 for the cheapest stuff. Add $1000 for TSO'd stuff. Add more for lighted stuff, annunciator, etc.

MGL Extreme/w AHRS, (includes pitot/static instruments) = $1400

You choose.
 
Oh yea

I forgot that the D-10 and other "lite" EFIS's will also provide accurate and reliable and maintenance free heading info integral to the unit (no second instrument required), either as standard or for a minor upgrade.

Sooo.... why was it that we should consider using vacuum again???????
 
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G-196

There's a Garmin 196 FS today on this site for $375, not only has all the nav you want but also that handy panel page if your EFIS goes South. If all your electrons go away it has battery backup giving you time to get on the ground at least.

Vacuum system? No way! YMMV
 
Sam Buchanan said:
If you go vacuum, might as well put an ADF in it, too. ;)
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And make sure it is one of those old ADFs with the crank you turn to change the frequency. The ones with the individual knobs where you can actually be sure what frequency you have selected are for lazy wusses.
 
aerhed said:
MGL Extreme/w AHRS, (includes pitot/static instruments) = $1400
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I'd buy one if it was this price, the Extreme with the SP2 and SP4 AHARS/Compass sensors is $2410.

Maybe there will be an Osh special for $1400 :D
 
Wardo said:
well its decision time. vacuum pump or no vacuum pump, that is the question.
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The only opinion on this subject that matters is yours.

The industry has gone electric and did so quite some time ago, the reason being cost and reliability. If you decided to buy a new 172, I doubt a vacuum system is an option these days. The entire panel is glass.

I don't understand all the concern about a back up system. If the engine quits in weather or at night your goose has just been cooked, a back up AI won't fix that scenario. Better not to be exposed like that in the first place. Flying at night and in weather in these airplanes induces stress which is bad for the cardiovascular system.

KISS, live longer and have more fun.

The less an airplane weighs the more fun it is to fly.

Vacuum pumps, hoses, filters and air driven instruments are great items for a museum. :)
 
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