Don’t skip partial panel work

srp_4737

srp_4737

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sr_4737
Had a full vacuum failure VFR on top (on an IFR flight plan) today in a ‘63 Cherokee over Arkansas and lost my AI almost immediately. There was a sea of clouds in all directions (tops were 5500-6000) but luckily ceilings were anywhere from 1200-2200 at most airports within range. I immediately declared an emergency and center was AMAZING in finding the best place for us to put it down. I was able to find a thinner area of clouds but had to go partial panel in actual for a bit. Thankfully we made it safe and I’m writing this stranded in a town I’ve never been . Hats off to the controllers and hats off to my CFI who threw a partial panel approach at me last time we did a currency flight a few months ago. Don’t let that skill slip… it can happen! I was super super lucky today. If anyone wants to see the flightaware track let me know!
 
Yep, glad it worked out too.

When flying a ‘63 Cherokee’ leave a little margin for contingencies.
 
Nicely done. Especially declaring an emergency right away.
 
srp_4737 said:
Had a full vacuum failure VFR on top (on an IFR flight plan) today in a ‘63 Cherokee over Arkansas and lost my AI almost immediately. There was a sea of clouds in all directions (tops were 5500-6000) but luckily ceilings were anywhere from 1200-2200 at most airports within range. I immediately declared an emergency and center was AMAZING in finding the best place for us to put it down. I was able to find a thinner area of clouds but had to go partial panel in actual for a bit. Thankfully we made it safe and I’m writing this stranded in a town I’ve never been . Hats off to the controllers and hats off to my CFI who threw a partial panel approach at me last time we did a currency flight a few months ago. Don’t let that skill slip… it can happen! I was super super lucky today. If anyone wants to see the flightaware track let me know!
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Sounds like you were prepared and used your training, cool!

Now take that AI and cast it into the sun. Replace it with an electric AV30 or something similar, whatever is certified for your a/c
 
Bravo! Great confidence benefit there, and just makes ya feel pilot like.
 
srp_4737 said:
Thanks! I think a big part of why I declared so early was watching this ASI video recently:
Accident Case Study: Single Point Failure - YouTube

This guy lost his vacuum system VFR on top and didn't survive the ordeal. Of course he had lower ceilings to deal with than I did. I was very lucky it was MVFR almost everywhere.
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Are you thinking about installing an electronic attitude indicator?
 
srp_4737 said:
Had a full vacuum failure VFR on top (on an IFR flight plan) today in a ‘63 Cherokee over Arkansas and lost my AI almost immediately. There was a sea of clouds in all directions (tops were 5500-6000) but luckily ceilings were anywhere from 1200-2200 at most airports within range. I immediately declared an emergency and center was AMAZING in finding the best place for us to put it down. I was able to find a thinner area of clouds but had to go partial panel in actual for a bit. Thankfully we made it safe and I’m writing this stranded in a town I’ve never been . Hats off to the controllers and hats off to my CFI who threw a partial panel approach at me last time we did a currency flight a few months ago. Don’t let that skill slip… it can happen! I was super super lucky today. If anyone wants to see the flightaware track let me know!
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Good job. You said you lost the AI almost immediately. Some failures don't happen that way. Sometimes it's a slow process and weird things can happen. Recognition of impeding failure is just as important as being able to fly partial panel.
 
srp_4737 said:
Had a full vacuum failure VFR on top (on an IFR flight plan) today in a ‘63 Cherokee over Arkansas and lost my AI almost immediately. There was a sea of clouds in all directions (tops were 5500-6000) but luckily ceilings were anywhere from 1200-2200 at most airports within range. I immediately declared an emergency and center was AMAZING in finding the best place for us to put it down. I was able to find a thinner area of clouds but had to go partial panel in actual for a bit. Thankfully we made it safe and I’m writing this stranded in a town I’ve never been . Hats off to the controllers and hats off to my CFI who threw a partial panel approach at me last time we did a currency flight a few months ago. Don’t let that skill slip… it can happen! I was super super lucky today. If anyone wants to see the flightaware track let me know!
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Be honest, how old and how many hours were on that pump?
 
luvflyin said:
Good job. You said you lost the AI almost immediately. Some failures don't happen that way. Sometimes it's a slow process and weird things can happen. Recognition of impeding failure is just as important as being able to fly partial panel.
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Not only that, but it happened while he was "on top", as opposed to in the clouds while flying on the failing instrument.

There are so many inexpensive electronic AHI's on the market today. Why would anyone fly IFR without one?
 
Glad you did partial panel on your recurrent. I did that as a regular thing, as I considered partial opanel skills to be paramount. Full panel flying is routine, you can keep yourself sharp solo.

Did you have an electric gyro, such as a turn and bank/turn coordinator? All the planes that I have owned had that, which takes the totality away, you still have a means of keeping banks under control.
 
AKBill said:
Are you thinking about installing an electronic attitude indicator?
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Not my call, it is a club airplane.

Clip4 said:
Be honest, how old and how many hours were on that pump?
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Not sure to be honest. It is a club airplane but I'll see if I can dig up some maintenance records to answer that. We don't even know 100% what exactly failed yet. All I know is the AI started to drift away from reality, at that moment I noticed the suction gauge was at zero, and within 1-2 minutes it was tumbled completely. Most likely the pump, but we need to verify. The club is on it and will keep me informed.

flybill said:
What town are you stuck in?
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Mena, Ar - Actually found a really cool brewery / pizza place and had a good time.

geezer said:
Glad you did partial panel on your recurrent. I did that as a regular thing, as I considered partial opanel skills to be paramount. Full panel flying is routine, you can keep yourself sharp solo.

Did you have an electric gyro, such as a turn and bank/turn coordinator? All the planes that I have owned had that, which takes the totality away, you still have a means of keeping banks under control.
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Yes I did have a turn coordinator which I utilized to interpret my bank.

Here are a few pics within minutes of noticing an issue. I was lucky to be VFR in between some layers.
 

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srp_4737 said:
Had a full vacuum failure VFR on top (on an IFR flight plan) today in a ‘63 Cherokee over Arkansas and lost my AI almost immediately. There was a sea of clouds in all directions (tops were 5500-6000) but luckily ceilings were anywhere from 1200-2200 at most airports within range. I immediately declared an emergency and center was AMAZING in finding the best place for us to put it down. I was able to find a thinner area of clouds but had to go partial panel in actual for a bit. Thankfully we made it safe and I’m writing this stranded in a town I’ve never been . Hats off to the controllers and hats off to my CFI who threw a partial panel approach at me last time we did a currency flight a few months ago. Don’t let that skill slip… it can happen! I was super super lucky today. If anyone wants to see the flightaware track let me know!
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That's great advice, and it applies equally to those with glass and solid-state AHRS. Things go wrong: relays fail, alternators bonk out, etc, and you can easily find yourself relying on a couple of tiny backup gauges off at the side (vacuum or battery or even portable) to keep the dirty side down.

If you don't practice with them now, they'll be no use when the time comes.
 
luvflyin said:
Good job. You said you lost the AI almost immediately. Some failures don't happen that way. Sometimes it's a slow process and weird things can happen. Recognition of impeding failure is just as important as being able to fly partial panel.
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"Immediately" meaning a few minutes from first noticing the problem. It started to drift upwards indicating I was in a climb, I clearly wasn't, looked over at my suction gauge which now read zero, then watched the thing tumble within a minute or so.
 
MauleSkinner said:
Because a Cherokee is just as easy to fly using needle and ball as it is using an AI.
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That's true. It's very difficult (almost impossible) to find an example of a fatal accident caused by a vacuum failure in a fixed-gear plane flown by an IFR-current pilot on an IFR flight — the fatalities are all in retractables. I suspect the gear acts as a speed brake and slows down spiral entry enough that the pilot doesn't end up behind the plane.

That's backed up by the famous 2001 ASF/FAA study in planes rigged up to simulate an actual vacuum failure. The Bonanza (retractable) group was much more experienced and spotted the vacuum failure quickly, but 25% of them still lost control and "died." The Archer pilots (fixed gear) were less experienced, took around six minutes to recognize the failure (!!!), and flew sloppily, but 100% of them still "survived" through to an instrument approach and landing.

http://www.aero-news.net/index.cfm?do=main.textpost&id=450ffe49-129b-496d-ad41-819c75601982
 
David Megginson said:
I suspect the gear acts as a speed brake and slows down spiral entry enough that the pilot doesn't end up behind the plane.
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I’d also suspect that most fixed-gear airplanes have a smaller speed range, and therefore require less trimming…I can think of a couple of accidents where the pilot’s left thumb was probably contributory.
 
srp_4737 said:
Had a full vacuum failure VFR on top (on an IFR flight plan) today in a ‘63 Cherokee over Arkansas and lost my AI almost immediately. There was a sea of clouds in all directions (tops were 5500-6000) but luckily ceilings were anywhere from 1200-2200 at most airports within range. I immediately declared an emergency and center was AMAZING in finding the best place for us to put it down. I was able to find a thinner area of clouds but had to go partial panel in actual for a bit. Thankfully we made it safe and I’m writing this stranded in a town I’ve never been . Hats off to the controllers and hats off to my CFI who threw a partial panel approach at me last time we did a currency flight a few months ago. Don’t let that skill slip… it can happen! I was super super lucky today. If anyone wants to see the flightaware track let me know!
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Great job. You did well. I teach in a Redbird motion simulator, and in nearly every time I fail the vacuum, the pilot makes a 360 before realizing what had happened.
 
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It's the same old story. Run stuff until it fails, and it often does it at a bad time. I wish I knew why schools, clubs and FBOs especially, don't do proactive maintenance and inspections on their vacuum pumps, magnetos and alternators. On POA it's a constant litany of stories of inflight failures, often resulting in an expensive delay in the trip. False economy.

Most sudden vacuum failures are the pump's fault, with worn-out vanes jamming in the rotor and shattering it. It can be a bad deal for the vacuum instruments, too, since those instruments act as little vacuum tanks and when the pressure suddenly quits they suck that carbon debris back up the vacuum lines and into themselves. Doesn't do them any good. It contaminates the hoses and lines, too, meaning that you either clean the entire system, or risk the new pump sucking in that junk and shortening its life. More time and money.

An old pump can suffer a broken drive coupling. They have a six-year life limit on them. They're plastic, and they age and harden and crack. New pumps come with new couplings.
 
sourdough44 said:
Yep, glad it worked out too.

When flying a ‘63 Cherokee’ leave a little margin for contingencies.
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Why we knocking a '63 Cherokee? (I also have one.)

OP, good job on declaring. Too often we hear guys wishing they had declared sooner or it being too late.
 
To me, a vacuum failure in IMC is one of the most insidious failures that can happen. One, it can be very gradual and difficult to detect. Things aren't looking or feeling right, but you can't figure why. Two, its hard to train for outside of a simulator. We can't fail your vacuum or gyros realistically in an airplane, your instructor just covers up the instruments. It can be terribly difficult to identify, then ignore, the failing AI and DG in the real world.
 
Dan Thomas said:
I wish I knew why schools, clubs and FBOs especially, don't do proactive maintenance and inspections on their vacuum pumps, magnetos and alternators.
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I would guess it has to do with money and the cost of replacing the parts.
 
edessa said:
I would guess it has to do with money and the cost of replacing the parts.
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Stalls, steep turns, and hard landing cause gyro instruments to have a higher failure rate than the pilot flying XC in his own plane.

If you are a active flight school and have some intelligence you have dumped Vac systems and instruments for G5s a long time ago because they are cheaper to maintain and you have less down time due to failed instruments and pumps.
 
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Clip4 said:
Stalls, steep turns, and hard landing cause gyro instruments to have a higher failure rate than the pilot flying XC in his own plane.

If you are a active flight school and have some intelligence you have dumped Vac systems and instruments for G5s a long time ago because they are cheaper to maintain and you have less down time due to failed instruments and pumps.
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We did spins and steep turns all the time in our steam-gauge airplanes. We used to have gyro issues. The difference between having gyro failures and not having gyro failures was the heated hangar. Gyros suffer terribly starting in the cold.

It's false economy, like I said, running stuff until it quits. It's not just the safety risks; it's contaminated instruments and lines from failed pumps; it's magetoes beyond economical repair from corrosion and general neglect; it's unrepairable alternators resulting from failed brushes and their springs chewing up the slip rings.

Ignore it all for now and pay way more later. It's like never changing the oil and filters in your car until you have to replace the engine.
 
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midwestpa24 said:
To me, a vacuum failure in IMC is one of the most insidious failures that can happen. One, it can be very gradual and difficult to detect. Things aren't looking or feeling right, but you can't figure why. Two, its hard to train for outside of a simulator. We can't fail your vacuum or gyros realistically in an airplane, your instructor just covers up the instruments. It can be terribly difficult to identify, then ignore, the failing AI and DG in the real world.
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Having had a couple one vacuum and a couple of gyro failures in IMC, I didn’t find it all that difficult to identify…a few degrees of bank indicated, but when I leveled the wings, the DG started turning. I think if you’ve got a good scan, they’re not difficult to detect.

ignoring bad instruments can be much more difficult IMO, but at the time I didn’t use the AI for much anyway, so needle, ball, and airspeed was actually my normal mode.
 
David Megginson said:
It's very difficult (almost impossible) to find an example of a fatal accident caused by a vacuum failure in a fixed-gear plane flown by an IFR-current pilot on an IFR flight
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Would the accident investigation detect that cause through forensic examination, or would it would get chalked up to "spatial disorientation"?
 
Ed Haywood said:
Would the accident investigation detect that cause through forensic examination, or would it would get chalked up to "spatial disorientation"?
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Often, the pilot tells ATC. IIRC, they also look at scoring inside the gyros to see how fast they were still spinning on impact.

Agreed that they wouldn't detect every case, but they detect many accidents for retractables where a vacuum failure in IMC is a primary cause, and if that were they case for fixed-gear planes, there's no reason they'd detect it less often.
 
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MauleSkinner said:
Having had a couple one vacuum and a couple of gyro failures in IMC, I didn’t find it all that difficult to identify…a few degrees of bank indicated, but when I leveled the wings, the DG started turning. I think if you’ve got a good scan, they’re not difficult to detect.

ignoring bad instruments can be much more difficult IMO, but at the time I didn’t use the AI for much anyway, so needle, ball, and airspeed was actually my normal mode.
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My one vacuum failure was in night VMC, and was a non issue on a clear night with lots of ground lighting.

I also had a joint AI and ASI failure in low IMC (instrument failure for the AI; blocked pitot for the ASI). In my draggy PA-28-161, hand flown, continuing for 30–40 min until I broke out at 600 ft on an ILS was also a non-event. Still having the DG helped, but lack of an ASI counteracted that a bit.

I doubt it would have been nearly so easy in a retractable, unless I'd been smart enough to drop the gear at the first sign of trouble and make it less slippery.
 
midwestpa24 said:
http://www.kathrynsreport.com/2016/05/beech-v35b-bonanza-n440h-fatal-accident.html

This is just one I can think of off the top of my head, but there are others. Not sure why it would matter fixed gear versus retractable?
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That's the same crash behind the Accident Case Study video that the OP linked to in post #9. The discussion above about things getting out of hand faster in a slick retract than in a draggy fixed-gear plane makes some sense to me.

Regardless, losing any of the top-row instruments (ASI, AI, altimeter) in IMC is an automatic emergency that should be declared early and often. ATC won't fly the plane for you, but they might be able to find a good place to land (and talk you into it if you second-guess), while you focus more of your brainpower on ignoring the dishonest portion of your panel.
 
Dan Thomas said:
We did spins and steep turns all the time in our steam-gauge airplanes. We used to have gyro issues. The difference between having gyro failures and not having gyro failures was the heated hangar. Gyros suffer terribly starting in the cold.

It's false economy, like I said, running stuff until it quits. It's not just the safety risks; it's contaminated instruments and lines from failed pumps; it's magetoes beyond economical repair from corrosion and general neglect; it's unrepairable alternators resulting from failed brushes and their springs chewing up the slip rings.

Ignore it all for now and pay way more later. It's like never changing the oil and filters in your car until you have to replace the engine.
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Agree on cold, but we still had premature failures in warm conditions. On the new SR22s an option is Tanis Avionics and Engine Preheat. Never thought avionics suffered much.
 
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iamtheari said:
That's the same crash behind the Accident Case Study video that the OP linked to in post #9. The discussion above about things getting out of hand faster in a slick retract than in a draggy fixed-gear plane makes some sense to me.
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Eh...I'll give that a maybe. I've flown both, and usually the retracts I've flown have been bigger, heavier, more stable aircraft, not to mention better equipped. The only real difference is if you start going downhill, you are going to be going downhill faster. 1,000 fpm descent in a 172 may be a little steep, in a Baron it is normal, in a jet it is hardly noticeable.
 
Dan Thomas said:
Gyros suffer terribly starting in the cold.
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In Alaska during the winter, we had electric heaters inside the plane under the instruments. On startup the gyros would howl like banshees until they warmed up.
 
iamtheari said:
That's the same crash behind the Accident Case Study video that the OP linked to in post #9. The discussion above about things getting out of hand faster in a slick retract than in a draggy fixed-gear plane makes some sense to me.

Regardless, losing any of the top-row instruments (ASI, AI, altimeter) in IMC is an automatic emergency that should be declared early and often. ATC won't fly the plane for you, but they might be able to find a good place to land (and talk you into it if you second-guess), while you focus more of your brainpower on ignoring the dishonest portion of your panel.
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Agreed. Once I declared ATC started assisting me in finding airports around with the best ceilings/vis. They were even attempting to call the FBO's and METARS to double verify what conditions actually looked like. Very grateful for the help! Yes - we should all have the ability to fly partial panel and remain in control of the aircraft... but with the wife next to me.. the ASI video in my head... I 'm glad I declared and I'm glad ATC did some leg work for me. :)

Also another interesting thing to note: My brain kept wanting my eyes to look at the faulty AI so I covered it up with a piece of paper from my notepad. Helped tremendously.
 
midwestpa24 said:
http://www.kathrynsreport.com/2016/05/beech-v35b-bonanza-n440h-fatal-accident.html

This is just one I can think of off the top of my head, but there are others. Not sure why it would matter fixed gear versus retractable?
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At 1539, the pilot reported that more of the instruments had failed and that he was turning to 060° and trying to get back to 7,000 ft.

This is one of several accidents I've studied where the pilot reported additional instrument failures after the vacuum system failed. This accident report didn't mention it, but some I have read about with these supposed additional failures following the vacuum system found the other instruments, usually the ASI and altimeter, were in good operating condition and there was no icing involved that might have blocked the pitot.

This 2016 crash of a Citation in Utah had similarities, but the NTSB report doesn't state there were actually malfunctioning instruments and avionics. I believe the condition of the highly fragmented wreckage precluded that.

https://reports.aviation-safety.net/2016/20160118-0_C525_N711BX.pdf

It appears that while pilots in these cases report the secondary malfunctions, what's really occurring is a loss of control, and they don't believe it.

One similarity in both of the accidents I have mentioned is that both pilots told ATC they wanted to continue to the destination airport.

The Bonanza pilot overflew BDL, with its multiple long runways and ILS approaches, and was near FRG when the plane crashed. He was headed for Robertson Field, which had an RNAV approach to 3665' Runway 02. The Citation pilot's destination was TUS, Tuscon. It was hundreds of miles away, the aircraft was reportedly experiencing autopilot and FMS failures, yet he declined to declare an emergency and seek a nearby airport.
 
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