The International Cessna^® 170 Association

Assume you are flying along fat dumb and happy, looking down at the ground senery. Suddenly you look up and you have lost all visibilty. What to do? A scan of the instruments shows the AH tilted and the DG going round and round. A glance at the wet compass shows it steady, the airspeed is steady, ( unless you started yanking and turning ). So what instrument is most important. Well for me it is the BALL of the T&B, KEEP it in the center, you are trimed for level flight already, so you are fine as long as there is no cumulogranite in front of you. But just in case it would probably be a good idea to get out of the clouds. So, make a mental note of the compass heading, subtract or add 180 degrees, gently start a standard rate turn using the T&B, keeping the BALL in the center. two fingers on the yoke, airspeed is steady if you don't push or pull. glance from the BALL to compass, to airspeed, to the BALL. It will seem forever but when you reach the 180 degree heading, gently center the needle ( or little wings ) keeping the BALL centered. Then wait till you break out. WHY keep the BALL centered???? Well, get a competent Instructor and clime to a safe altitude in a practice area and do a decending spiral with a centered BALL and try it with a out of centered BALL and see what happens. When the seat foam starts comming out your ears you will know why to KEEP THE BALL CENTERED.

blueldr wrote:AR Dave,
Please don't fly into a cloud. You're gonna die!

Blue, I realy admire a guy who can cut to the quick then way you can.

OK let’s try this again - Thanks for some of the short comments! I wouldn't be leaving myself out for the bashing, if I wasn't very experienced flying with 0 visibility! As a side note* this forum doesn't exactly encourage pilots to ask stupid questions, now does it!

My opening statement was - when I find myself unable to see outside the fuselage this is what I do - Blue Elder! If you are only VFR rated and can’t temporarily fly in clouds, then your flight instructor is cheating you on your hood time.

George, you made some good points about how to recover from unusual attitudes. Veered from the point but - anyway. I must be flying the old style like was written in your book. In Oct I went through my BFR again. The instructor turned that plane nearly upside down, trying to disorient me while I was under the hood. I just love recovery and always challenge the instructor's to try messing me up again. Maybe you can give me an 08 BFR? We could test each other both with the vacuum system on and without it.

The Speed Indicator, Altitude Indicator, and the Elec T&B. I use the T&B for leveling wings. And I use the Heading Indicator ASAP. But I just don’t need that Artificial Horizon. What would be the best instrument to use if the Heading Indicator where lost?

THE QUESTION IS "How dependent are we on our Attitude Indicator and Heading Indicator"? And why are certain pilots going to fall out of the sky if the vacuum system is lost?

It has suddenly occurred to me where the paranoia of loosing your vacuum system comes from. Let's discuss what you are going to do - if!

Dave to be honest while I was waiting for George's nimble fingers I had the same reaction to your comment as BL.

I was trying to figure out if you understood and had experience with more than your comments indicated. I suspected you did. I know think I understand what you where trying to convey.

You are right with you observations of the airspeed indicator in that it is a secondary source of information. Secondary because as George points out it isn't as quick to indicate what's going on with the aircraft.

This is not to say it shouldn't be used in conjunction with all other resources when the AR fails.

Pilots should not crash simply because of a loss of the vacuum pump alone. But they must be prepared (trained) to fly with out it. How many of us casual VFR/IFR pilots practice IFR partial panel. I'll admit not me.

THE QUESTION IS "How dependent are we on our Attitude Indicator and Heading Indicator"? And why are certain pilots going to fall out of the sky if the vacuum system is lost?

Dave,

I think that with a vacuum system failure the indications that the failure occurred are very insidious and even very experienced pilots can have trouble recovering if they don’t recognize the system failure and immediately disregard the 2 primary vacuum instruments or cover them up. I too like to recover from unusual attitudes but that is mostly because I like getting into the unusual attitudes in the first place. The difference is it is easy to do if you know that you are in an unusual attitude but if you know in your heart that you are flying straight and level but the airplane is in a 90 degree bank then the complexity goes up exponentially and this is where good pilots crash airplanes.

AR Dave wrote:...THE QUESTION IS "How dependent are we on our Attitude Indicator and Heading Indicator"? And why are certain pilots going to fall out of the sky if the vacuum system is lost?

It has suddenly occurred to me where the paranoia of loosing your vacuum system comes from. Let's discuss what you are going to do - if!

With Joe's recent re-posting of his loss-of-control experience, I did some research and recalled this thread. While re-reading this thread I also realized that AR Dave's question was actually a good one.
Dave seemed to feel that his Primary question had gone unaddressed.
I didn't view that as the Primary, but as a Secondary one. The answer to that Seconday question, IMHO, is still the same one I offered earlier: Attitude is the information we are needful of, and the AH is the primary instrument that provides that info. This is not to the exclusion of scanning other, Secondary, instruments for confirmation of the validity of that AH.
In virtually every case, without any action from the pilot at all, these airplanes will continue to do for the next 10 seconds the same thing they've been doing for the last 10 seconds.

The Primary question was actually asked in an earlier post:

AR Dave wrote:...When I go VFRIFR, my eyes immediately go to the Airspeed Indicator and don't stray very far there after. 1st thought - Don't Stall ...Am I forgetting something or mixing my instruments up?...

That is what my previous answer (last Nov.) attempted to address.
Looking at the AS first...for attitude info.... is not what should be done. (If the airplane inadvertently enters cloud and has been flying for the last 10 seconds it will likely continue to do so for another 10 seconds (it won't just "STALL") while the pilot first looks at the AH...then confirms the AH's info with the secondary instruments: AS/T&B/ALT/VSI/Compass.)
Looking only at AH or DG in everyday flying may result in a perhaps excessive-dependancy upon those instruments.
The best "overall picture" is obtained from a regular, complete, instrument scan. Scan all available info and a pilot will become aware much sooner that a failure has occured. This requires practice, and regular recurrent training with a qualified instructor/safety pilot.

I had an unusuall attitude experience a few years ago while crossing Lake Michigan in VFR conditions. I was flying at 10,500ft and studying my chart when I heard the engine start picking up speed. The first thing I did as a VFR only pilot was to look out the windows to level the wings. I soon realized that that was pointless as there was no horizon to work with. Next I remember thinking "this is the kind of thing that kills people" Next I looked at the attitude indicator and turn coordinator and noticed the were going in the opposite direction. At that point I thought "you better calm down think calmlly for a few seconds or this will kill you." At that point I used the attitude indicator to level the wings, threw the chart in the back seat, crossed checked my insturments and flew due east until I was over the eastern shore of the lake. Seems like one of the hardest things in these situations is to calm down and think. I was once flying with a seasoned IFR pilot in a twin when the auto pilot malfuctioned. His first reaction was to inccrease the bank angle in the wrong direction. I was sitting in the right seat and said howbout we try this way to level the wings and he quickly agreed. He was quite embarassed afterward but I think in situations like this it is quite common for pilots to react incorrectly at first. I have no doubt that had I not been there he would have gotten straightened out in due time. It all boils down to remain calm an level the wings first. The attitude indicator would definitly be the primary instrument. Bill K

With no gyros in a low or no viz situation the so called HSI display on your GPS might help you stop any turns before your bank got to steep. If I had a Garmin 196 Id definitely be on the panel page in those conditions.

I've got a Garmin 196 and it was with interest that I tested that "panel page" against the aircraft instruments in various situations. The Garmin 196 is definitely a positive feature.
But it's important to realize that the 196 displays that info only as the result of a navigational change in direction...not as an actual depiction of aircraft attitude or configuration. It gives a history-lesson of what has been happening, and very recently, true ....but not really what is happening right now! (Since it's only a reflection of navigation progress, related as probable cockpit instrument simulations, certain other errors can occur as well. An upside-down descending spiral can look the same as a base turn-to-final.)
If things don't get too far progressed along the path-to-destruction, the 196 can be a valuable tool. However, even as a relatively experienced, instrument-rated pilot and instructor I would not want to have to use it. I'd be in adrenalin-rush by then. (And be aware that it's altitude indicator can be pretty far off. I've seen more than 1,000' from time to time.)

My discussion was started after reading the article, which stated that "95% of you are going to die if you loose visibility and your vacuum system”! I was curious why 95% of you are going to die. Since I'm a good fellar, I thought I would bring up the question, "what are you going to do if you loose your vacuum, with no visibility?

For those of you that don't realize it - when you loose your vacuum - you loose your Attitude Indicator as well as your Heading Indicator.

I looked back over the post, myself, and realized that several folks have added some valuable insight. Rosebury explains it for me best!

Joe after we discussed this in TX, and it turned dark on me around the Red River, I turned the lights off of my Vacuum Instruments and flew home. I tried to imagine what if's! One thing that I'm doing more of – is paying attention to the Suction Gauge.

My final point is that there is no reason for 95% of you to die. Learn how to find your attitude and heading without the AI and the HI.

The Garmin 496 updates at 5 times/second, so close to real-time it looks like right now.

The Garmin 296 and 396 update at 1 time/second, 5 times slower but still fast enough that it's almost real-time and plenty well usable to stay out of trouble.

I don't know about the update rate of the Garmin 196 but I bet it's slower than 1 time/second if it doesn't update fast enough to make you comfortable using it.

A couple of summers ago I flew a relaxed 1-1/2 hour trip under the hood from Anchorage to Seldovia, about 170 miles in my C-180 using ONLY the 296. I had an FAA inspector as observer/safety pilot and we completely covered the rest of the instrument panel from view with a WAC chart. Not only could I keep the plane right side up using the panel page, after the initial jitters were over it was comfortable to the point I could page back and forth to look at terrain and map pages. I flew into Seldovia Bay, entered left downwind and looked up on final to see the runway right in front of the plane. The inspector said "If I hadn't seen it I wouldn't have believed it". It was not that hard. You're not going to hit anything that is not red on the terrain page.

It would be good insurance for everyone who has one of these Garmins to go under the hood with a safety pilot and fly the plane with it until you are comfortable. It could save your life.

For people who fly IFR, the GPS is no excuse for letting partial panel skills deteriorate though. Being able to fly the plane on needle, ball, airspeed, and altitude should be every pilots priority should the vacuum fail someday when in the clouds. And if both electrical and vacuum were to fail at the same time, the battery will keep the Garmin going for hours. It's not a cure-all solution and won't get you out of an unusual attitude situation but it sure can help keep you out of one if you know how to use it. And like everything else it takes practice to be competent.

Having the Garmin there is definitely good back-up and would be a major anxiety reducer if you are current with using it. It's cheap insurance to have along on every flight. I don't leave home without it.

The 196 also updates once every second, unless it's in WAAS mode in which case it updates every 5 seconds like the 496.

AR, Dave, the answer is still the same. Scan. Scan. Scan.

Good point George, turn off WAAS if you're using it for backup. I was not aware of that.

George a more useful answer is as Richard stated -

Being able to fly the plane on needle, ball, airspeed, and altitude should be every pilots priority should the vacuum fail someday when in the clouds.

gahorn wrote:The 196 also updates once every second, unless it's in WAAS mode in which case it updates every 5 seconds like the 496.

George, is it every 5 seconds, or five times per second like the 496?

John