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JoachimvMayern
09-18-2004, 09:35 PM
Regarding the topic of Spatial Disorientation, for those of you that do not know, read below as this is what killed JFK Jr. A quick setup here. Imagine you are flying alone at night in total darkness. You lose sense of the horizon. Your body thinks that the plane is flying straight but in reality it's not. The fluids of your inner ear are susceptible to changes in the flight path, but only when you make a change in the flight path. For instance, if you bank left, the fluids in your inner ear will pick up the change in flight path, but if you maintain that turn, the fluids will eventually balance out and deceive your brain, tricking it into thinking that it's still flying straight. Eventually you lose all awareness and before you know it, you just plunged straight into the ground.

Spatial Disorientation is the result of losing visual orientation to the horizon, which can occur in both VFR and IFR conditions. This can be due to clouds, fog, haze or extreme darkness without surface lighting to provide the needed horizon. Without training and experience in flying by instruments alone (no visual horizon), VFR pilots can suffer from vertigo, motion sickness, fatigue, poor hand-eye coordination (flight controls), impaired judgment and panic. VFR pilots who fly into these conditions literally place the life of themselves and their passengers into their hands.

My question regarding this topic is that if you are flying at night, regardless of what your brain thinks you are doing, shouldn't you be looking at your artificial horizon, IAS, nose pitch indicator and altimeter instead of continually staring out the window wandering and panicking? How hard is it to fly at night if you have all of those mentioned instruments on your plane? Any for real pilots want to take a stab at this one?

JoachimvMayern
09-18-2004, 09:35 PM
Regarding the topic of Spatial Disorientation, for those of you that do not know, read below as this is what killed JFK Jr. A quick setup here. Imagine you are flying alone at night in total darkness. You lose sense of the horizon. Your body thinks that the plane is flying straight but in reality it's not. The fluids of your inner ear are susceptible to changes in the flight path, but only when you make a change in the flight path. For instance, if you bank left, the fluids in your inner ear will pick up the change in flight path, but if you maintain that turn, the fluids will eventually balance out and deceive your brain, tricking it into thinking that it's still flying straight. Eventually you lose all awareness and before you know it, you just plunged straight into the ground.

Spatial Disorientation is the result of losing visual orientation to the horizon, which can occur in both VFR and IFR conditions. This can be due to clouds, fog, haze or extreme darkness without surface lighting to provide the needed horizon. Without training and experience in flying by instruments alone (no visual horizon), VFR pilots can suffer from vertigo, motion sickness, fatigue, poor hand-eye coordination (flight controls), impaired judgment and panic. VFR pilots who fly into these conditions literally place the life of themselves and their passengers into their hands.

My question regarding this topic is that if you are flying at night, regardless of what your brain thinks you are doing, shouldn't you be looking at your artificial horizon, IAS, nose pitch indicator and altimeter instead of continually staring out the window wandering and panicking? How hard is it to fly at night if you have all of those mentioned instruments on your plane? Any for real pilots want to take a stab at this one?

PBNA-Boosher
09-18-2004, 10:06 PM
Pretty simply, your instruments are your life. Make sure they are accurate before you take off, and then live your life by them. They can mean the difference between life and death in many situations.

Boosher
_____________________________
"So do all who live to see such times, but that is not for them to decide. All you have to decide is what to do with the time that is given to you..."
-Gandalf

El Turo
09-18-2004, 10:18 PM
The number one killer of general aviation pilots/passengers is "GET-THERE-ITIS". Flying under unsafe conditions because they just absolutely have to get wherever it is they're going. This is what kills quite a few famous people, and quite a few unfamous people as well.

Callsign "Turo" in IL2:FB & WWIIOL
______________________
This place
was once
a place
of worship
I thought,
reloading my rifle.

~V.

JoachimvMayern
09-18-2004, 10:23 PM
So IF all the instruments are working correctly, some pilots just freak out and turn the trust over to their brains instead of the flight instruments? I would love to try a Barany Chair just to see how I would do.

El Turo
09-18-2004, 10:30 PM
It takes quite a bit of discipline to ignore what your body is telling you. When you are training for your private pilot licenses, this is one of the things you must be exposed to by your instructor.

You can do something similar next time you are driving your car on a non-busy street and coming to a stop (perhaps better with a passenger not playing along with you). As you begin to slow down for the stop sign/light, establish a set amount of brake-pedal input that will stop you short of the light for sure, safely. Then, close your eyes and just try to FEEL the speed/acceleration of the car. You'll likely be suprised when the car does finally come to a complete stop with a bit of a final jolt.

Also, have you never been stopped at a light when a vehicle next to you, like a large truck, begins to pull forward and you get the momentary feeling that you are rolling backwards and panic?

Same idea.

Callsign "Turo" in IL2:FB & WWIIOL
______________________
This place
was once
a place
of worship
I thought,
reloading my rifle.

~V.

BinaryFalcon
09-18-2004, 10:34 PM
It depends. Night VFR in some cases can be very much a VFR type operation, where you can fly mainly by looking out of the window. Lots of non-instrument rated pilots do it and do it safely, so exclusive use of the instruments is not required.

On a few of my night cross country flights, I basically conducted them much as I would have during the day. Eyes outside with occasional glances at the panel to confirm things. For the most part, spatial disorientation (SD) isn't a huge problem so long as you have visual references.

However, it's been said (and I agree) that in a lot of cases, flying at night is basically flying IFR. Get a cloudy, moonless night over unpopulated areas or worse, water, and you'll quickly understand what I mean.

It's like flying in a void. There's no real sense of speed or movement or making any progress at all. All you've really got to go on is your instruments, since you can't see any details or even a horizon outside.

A full set of instruments will of course make all of this easier, but my first night flight ever I did partial panel. About 10 minutes after departure after leveling off at our cruising altitude my instructor told me to make a 90 degree left turn.

I looked down at the DG and started my turn. The DG seemed to be going a bit slow, but I kept turning. However, after about 30 seconds I knew I should have turned 90 degrees. The time was right, the view outside was right, but the DG was indicating less than half of that.

I rolled wings level and the DG immediately spun around twice so fast you couldn't even read it before finally coming to a halt and then beginning a slow, constant spin in the opposite direction. It was dead, and I called "DG failure" to my instructor, who asked, "Are you sure?" I pointed to it as it continued turning at a rate of around 6 deg/second and said, "Yep." He agreed, and so rather than terminate the local flight, we just used the mag compass when needed.

If needed, you could keep the plane under control in zero vis day or night with just 2 instruments. As long as you've got something that can provide some level of pitch information and something that can provide some level of turn information, you can at least manage straight and level.

I remember back in my early IFR training when my instructor decided to have a little fun, and he and another instructor put me in the sim and had me close my eyes. They then put me at 6,000' AGL, in a spin and failed everything but the airspeed indicator and the mag compass.

Then they told me to open my eyes and try to recover. It took me a few seconds to figure out what instruments I could still use, and I ended up reversing the spin twice, but I did manage to recover the aircraft at 40' AGL and then climb, descend, fly specific headings and maintain straight and level based only on airspeed and the compass.

Some of the initial recovery was just me being lucky, but keeping the plane under some amount of control even with the barest of instrumentation is possible so long as you know how to use it.

JFK jr's problems were that he overestimated his abilities, didn't understand his aircraft, didn't trust his instruments, and refused assistance when it was offered. Added to that he launched into conditions that more seasoned pilots would have not been as eager to fly into. It was a bad situation from the outset, and once he got disoriented it was over.

In fairness,
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>VFR pilots can suffer from vertigo, motion sickness... <HR></BLOCKQUOTE>
Instrument rated pilots can and do suffer from all of these too. Hopefully the knowledge and training that's supposed to come with an Instrument ticket allows them to overcome, or at least ignore those things.

It's still strange though, when you feel like you're tumbling backwards but your instruments tell you otherwise. After a couple of hours I learned how to "disconnect" my sense of balance from what I was doing. I still get all of the feelings, but it gets easier to selectively ignore them when IFR.

EDIT:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>So IF all the instruments are working correctly, some pilots just freak out and turn the trust over to their brains instead of the flight instruments? I would love to try a Barany Chair just to see how I would do.<HR></BLOCKQUOTE>

Essentially, yes.

The problem is that humans were not built to fly, especially not without visual references.

Our balance system is really pretty amazing, and for what we were designed to do (stay on the ground), it works extremely well. We have three semi-circular canals in each ear, and each (one per ear) is used to sense acceleration (not movement) in one axis.

They do this by being filled with fluid and tiny hairs. On top of these hairs rest small "rocks", or otoliths. When we move, the otoliths and fluid lag slightly due to inertia, and will cause the hairs they are resting on to bend. This sends a signal to our brains and tells us which way we're moving.

There are a couple of drawbacks to this system though. One, is that it has a certain, minimum threshold of acceleration that it can detect. I can't remember what it is for sure, but I want to say it's around 1.5 degrees/sec for turning. It's been a few years so I'd have to look it up again to be sure.

The second problem is that it only sense acceleration, not actual movement. What this means is that if you are subjected to constant acceleration, after a few seconds the otoliths and hairs in the canals will center up again. This sends a message to your brain that you have again slowed and come to a stop, which is not the case.

If you then really do come to a stop, the otoliths try to keep moving and bend the hairs again, which tells your brain that you have started moving in the opposite direction.

That's how pilots can get into the "graveyard spiral". They end up in a constant rate turn, and after a few moments they feel as though they have returned to straight and level. They don't realize that they are turning any longer and end up spiralling in. Or they check the instruments, correct and then feel like they're turning the other way, so they ignore the instruments and go with what "feels" right. That puts them back into a turn and further confuses them.

Other common "tricks" are that speeding up while remaining level will make you feel as though you are climbing (so you'll shove the nose down to compensate if you are flying by feel), or if you slow down while level you'll feel as if you are pitching down, so you'll try to raise the nose if you are flying on feel.

Any good flight physiology or medical textbook should explain the biology of it fairly well. It's interesting stuff, and IMO essential to understand if you intend to fly, IFR or not.

[This message was edited by BinaryFalcon on Sat September 18 2004 at 09:54 PM.]

Dolemite-
09-18-2004, 11:21 PM
JFK Jr. wasnt instrument rated, and if Im flying in very low vis conditions at night/thru clouds I go into a climb rather than flying straight and level or going into an immediate dive.

Oh, and driving your car with your eyes closed is not a good idea either.

__________________________________________________ ______
Flying on HL as {Dolemite}
http://www.talonse.com/supergreg.swf &lt;----- ya wont regret it

BfHeFwMe
09-19-2004, 02:04 AM
One of the toughest times any crew I've been on had was making an unfamiliar approach into clear desert skies at night in Egypt. Minimal nav aids at the time, the area was like a fish bowl full of stars, you couldn't see any horizon or tell which were ground lights as opposed to the stars. The fact my squadron lost a crew on the same approach three years earlier didn't help smooth things either.

Hard to spot one of their airbases even in the day time. They don't turn on the lights till your on final, and than they are quite dim. Paranoia I guess. You know your low, but can't see nothing, getting close to decision, time to panic.

Otherwise weather has been a far bigger hassel and scarier than any night flying ever was.

Eraser_tr
09-19-2004, 07:05 AM
"Oh, and driving your car with your eyes closed is not a good idea either." but sometimes it can be impossible to avoid. like if you reallyhave to sneeze sometimes http://ubbxforums.ubi.com/infopop/emoticons/icon_razz.gif

Trusting your instruments and ignoring your body is actually what has brought down planes in the bermuda triangle, not aliens or ghost ships or anything like that. Gas trapped under the surface comes loose and rises into the atmosphere. because of the gas, the plane's altimiter reads that it is climbing. The pilots see this and pitch the nose down even though they are flying level. They are actually diving and their body feels it, but they ignore it because of the instruments. Thusly they nose dive into the water.

I by no means have any experience but in a case like that, I think you should trust your body. Instruments don't feel inertia. But if you are flying blind and don't feel anything with your body, trust the instruments.

mortoma
09-19-2004, 09:01 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Eraser_tr:
"Oh, and driving your car with your eyes closed is not a good idea either." but sometimes it can be impossible to avoid. like if you reallyhave to sneeze sometimes http://ubbxforums.ubi.com/infopop/emoticons/icon_razz.gif

Trusting your instruments and ignoring your body is actually what has brought down planes in the bermuda triangle, not aliens or ghost ships or anything like that. Gas trapped under the surface comes loose and rises into the atmosphere. because of the gas, the plane's altimiter reads that it is climbing. The pilots see this and pitch the nose down even though they are flying level. They are actually diving and their body feels it, but they ignore it because of the instruments. Thusly they nose dive into the water.

I by no means have any experience but in a case like that, I think you should trust your body. Instruments don't feel inertia. But if you are flying blind and don't feel anything with your body, trust the instruments.<HR></BLOCKQUOTE>Never heard of this theory, but I have heard that gas in the Bermuda triangle can cause ships to loose bouyancy and sink into the depths, even though they are otherwise perfectly good ships. They have never proven this stuff though. But it sounds to me that it would be a good idea to take a GPS and use it's altimeter as a backup in the Bermuda triangle, just in case!!

Maple_Tiger
09-19-2004, 09:29 AM
I suffer from Spatial Disorientation when I wake up in the morning.

Capt. 361stMapleTiger.
http://img52.photobucket.com/albums/v158/Maple_Tiger/FBAA2.gif
Proud member of the FBAA and Nutty Philosohpy Club.
-----------------------------
The more less you'r travelling, the further back in time you go.


I am hear,
but not quite there.
I am near,
Come if you dare.

Kefuddle
09-19-2004, 10:21 AM
Two things:

1) Some confusion of the term IFR abounds! There is VMC (Visual Met Conditions) and there is IMC (Instrument Met Conditions). VMC (also known as Victor Mike Charlie) is when you can maintain visual contact with the ground and visability is above minima (some counties allow VMC ontop of the clouds). IMC is when niether of the above is true (in rain, cloud, etc). VFR (Visual Flight Rules) can only be flown in VMC. IFR (Instrument Flight Rules) can be flown in either VMC or IMC. Any body can fly IFR, it is the license rating that determines if you can fly in IMC or not.

2) Night flying with a Night Rating/Qualification is IFR in VMC. To fly day or night in IMC you need am Instrument Rating (or equivelent). You can navigate by radio beacons or by relative orientation to towns, cities and roads (or anything that is lit up). You will be suprised just how much you can see up there at night. It is important to keep cockpit lighting very low and use a red torch to prevent you eye becoming un accustomed to the dark though. It is fantastic. Even flying "on-top" (on top of cloud) ranks second to night flying. The air is smooth, the visibility often is amazing and the way that street lights, etc spill onto the surrounding land is quite sureal.

Night flying means that you do tend to make use of the instruments rather more than the day, especially if there is a layer of cloud above. On a clear night it is usually possible to see the horizon quite clearly. To answer the question, if you cannot remain VMC at night then you don't take off! Disorientation isn't really any issue in those conditions as there is seldom nothing to orientate yourself by. Without an Instrument Rating, only an idiot would plan a flight over a completely featureless terrain or water at night in the overcast with no moon.

The various comments about instruments being life are essentially true. However, as always it is a little more complex than that. Instruments (especially gyros) do go wrong on a not infequent basis. It is important that the pilot cross checks instruments to make sure they tally. For example: What would you do if the AI says straight and level by the ASI is increasing? I would look at the VSI to determine if I am descending, if so then I would discount the AI and concentrate on the turn indicator/coordinator ASI and VSI only (and the others as required), but the AI must now be ignored...easier said than done. IF the ASI is mesreading it is time to "PAN PAN" and land as soon as possible!!

BinaryFalcon
09-19-2004, 10:56 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Any body can fly IFR, it is the license rating that determines if you can fly in IMC or not.
<HR></BLOCKQUOTE>

This is not true in the United States (but may be in other countries).

According to 14 CFR 61.3(e) (http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/1E4B1601D9B5103586256EE0006417BE?OpenDocument):
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>
(e) Instrument rating. No person may act as pilot in command of a civil aircraft under IFR or in weather conditions less than the minimums prescribed for VFR flight unless that person holds:
(1) The appropriate aircraft category, class, type (if required), and instrument rating on that person's pilot certificate for any airplane, helicopter, or powered-lift being flown;
(2) An airline transport pilot certificate with the appropriate aircraft category, class, and type rating (if required) for the aircraft being flown;
(3) For a glider, a pilot certificate with a glider category rating and an airplane instrument rating; or
(4) For an airship, a commercial pilot certificate with a lighter-than-air category rating and airship class rating.
<HR></BLOCKQUOTE>

In summary: In the US, if you don't have the rating, you can't legally fly it and you can't file it.

Doesn't matter if it's a CAVU (ceiling and visibility unlimited) day, you can't file IFR unless you're instrument rated.

It can be a bit confusing, but as a rule, it goes like this:

You must be instrumented rated (and current) to file IFR.

You must file IFR if you wish to fly in IMC or in Class A airspace (above 18,000').

However, you can file and fly IFR under any weather conditions, even VMC.

If you're a VFR pilot, you are limited to VMC conditions.

karost
09-19-2004, 11:01 AM
good thread and good posts

I not a real pilot yet but I like to read about this knowledge becuase this thing may save my life someday http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

Thanks all guys
S!

LStarosta
09-19-2004, 11:10 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>I by no means have any experience but in a case like that, I think you should trust your body. Instruments don't feel inertia. But if you are flying blind and don't feel anything with your body, trust the instruments.<HR></BLOCKQUOTE>

I disagree. The whole point is that sometimes you do not feel the inertia, or the way you perceive the inertia is not akin to reality.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>The number one killer of general aviation pilots/passengers is "GET-THERE-ITIS". Flying under unsafe conditions because they just absolutely have to get wherever it is they're going. This is what kills quite a few famous people, and quite a few unfamous people as well.<HR></BLOCKQUOTE>

And yet some people earn their living meeting meterological deadlines in a commercial aircraft. http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif


I agree with the author of the thread, many is the time I flew through thoroughly blinding clouds thinking I was going straight until I glanced at the artificial horizon to realize that I was in a pretty decent bank...

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Spitfire = Technoblabble(Oleg/"Favors Recieved" from [wo]men)^PI(Magic 8 Ball)(amount of LSD Taken+Booze)(Position of the Earth Relative to the Sun)(Position of the Sun relative to God)^2

"You must factor in the alignment of the planets for the day in which the equation is completed, because the Spit can harness the power of the Earth's rotation and we're working on harnessing the power of ALL rotating and revolving objects in our solar system, later the whole universe, thus boosting the Spit's top speed to r0xx0rz KPH." -Dr. Nathan Roberts

Flying online as (56th)*MRBROWN

IL2-chuter
09-19-2004, 11:39 AM
My experiences with disorientation haven't been in obvious, no visibility situations. It's been when things gradually get worse, like when on a clear night a cold front appearing on the horizon gradually gives the impression the horizon is 30 or 40 degrees from horizontal. Sneaks up on me. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-indifferent.gif

It sure does take a lot of discipline to fly those instruments in the soup . . . everyone should try it . . . http://ubbxforums.ubi.com/images/smiley/16x16_smiley-happy.gif

"I fly only Full Real in Il2 Forgotten Battles." -Mark Donohue

El Turo
09-19-2004, 12:07 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Dolemite-:
Oh, and driving your car with your eyes closed is not a good idea either.<HR></BLOCKQUOTE>

Hence, why I said..

"..on a non-busy street and coming to a stop (perhaps better with a passenger not playing along with you)."

I strongly doubt you're going to kill yourself or anyone else in those last 10 feet of stopping under any kind of normal conditions.

Callsign "Turo" in IL2:FB & WWIIOL
______________________
This place
was once
a place
of worship
I thought,
reloading my rifle.

~V.

darkhorizon11
09-19-2004, 03:01 PM
"My question regarding this topic is that if you are flying at night, regardless of what your brain thinks you are doing, shouldn't you be looking at your artificial horizon, IAS, nose pitch indicator and altimeter instead of continually staring out the window wandering and panicking? How hard is it to fly at night if you have all of those mentioned instruments on your plane? Any for real pilots want to take a stab at this one?"

Its hard. Takes a lot of practice, I'm earning my instrument rating right now and it can be quite a pain. The key is resource management and having a good scan. For me learning to distrust my senses wasn't that hard, just the getting the good scan took practice. An attitude indicator is required per the FARs, but you can fly without it if you have to. Actually it isn't good to stare at to much as it is often a target for fixation with new private pilots under the hood. In fact the life of a private pilot with under 200 hours in IMC when losing an attitude indicator ussually isn't more than a few minutes. I was no different, I was in the sim in IMC in the beginning of my instrument training when my instructor did just that, and I crashed within about 3 and a half minutes. The trick is to ussually smooth and small corrections and fly the plane with no more than a few fingers. Use the altimeter, vertical speed indicator, airspeed indicator, and the most important instrument...the turn co-ordinator. Be careful not to chase the needles however as the actual numbers and readings aren't important as the rate and trend of each instrument. I hope that helps!

Jungmann
09-19-2004, 03:32 PM
Short, sad answer: JFK Jr. f***ed up.

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Jungmann

"Oh, the monkeys have no tails in Zamboanga..."

Covino
09-19-2004, 04:09 PM
I read this story of how when this flight crew was performing maintenence on an airliner, a crewmember left a piece of duct tape on the static port of the plane (measures airspeed/altitude). Long story short: the plane took off on a night flight and plunged into the ocean, killing everyone on board because the altimeter constantly read 10,000 ft. The crew member was charged with the homicide of 100 people or so.

I guess to answer your question, spatial disorientation can be so convincing that inexperienced pilots might not feel the need to check their intruments or they may trust their instincts more than their intsruments.

BinaryFalcon
09-19-2004, 04:10 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> An attitude indicator is required per the FARs, but you can fly without it if you have to. Actually it isn't good to stare at to much as it is often a target for fixation with new private pilots under the hood.<HR></BLOCKQUOTE>

I had that problem during my initial training, so my instructor really worked hard on breaking me of that habit by constantly failing the AI.

Unfortunately he did too good of a job, since I got so used to the AI being failed about 80% of the time I just started omitting it from my scan as a matter of course.

As a result, I was effectively flying partial panel a lot of the time even when things were all working correctly. It took me a while to break that habit again when I got to my multi course, because I still tended to omit the AI from my scan.

On the plus side, when I do include it in my scan, it makes instrument work seem like cake. http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

LStarosta
09-19-2004, 04:11 PM
Did he have intent to kill all those people?

Seems like it'd be manslaughter to me, but I dunno. Do you have a link to that story, it seems interesting.

http://home.comcast.net/~l.starosta/sig2.jpg
Spacer nad Berlinem!
Spitfire = Technoblabble(Oleg/"Favors Recieved" from [wo]men)^PI(Magic 8 Ball)(amount of LSD Taken+Booze)(Position of the Earth Relative to the Sun)(Position of the Sun relative to God)^2

"You must factor in the alignment of the planets for the day in which the equation is completed, because the Spit can harness the power of the Earth's rotation and we're working on harnessing the power of ALL rotating and revolving objects in our solar system, later the whole universe, thus boosting the Spit's top speed to r0xx0rz KPH." -Dr. Nathan Roberts

Flying online as (56th)*MRBROWN

BinaryFalcon
09-19-2004, 04:27 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>
I read this story of how when this flight crew was performing maintenence on an airliner, a crewmember left a piece of duct tape on the static port of the plane (measures airspeed/altitude). Long story short: the plane took off on a night flight and plunged into the ocean, killing everyone on board because the altimeter constantly read 10,000 ft.
<HR></BLOCKQUOTE>

I think I remember hearing of a similar accident, but it occurred somewhere in South America I believe. The plane had just come out of maintenance and had been washed. When they wash the planes, they tape over the ports like that to keep water from getting inside. If you miss some of the tape when you remove it, it can do bad things.

In that case, the flight crew got confused because the sealed static system acted like a barometer, and as they gained altitude their airspeed indicator started reading artifically high. That quickly triggered the mach warning horn in the cockpit, as the aircraft systems thought the plane was getting close to exceeding the speed of sound.

The pilots didn't understand what was going on, so they throttled back and raised the nose to try and slow down. As they climbed, indicated airspeed continued to rise, so they kept pulling power and rasing the nose. The plane slowed down to the edge of stall, and then they got hit with the stick shaker to warn them of an impending stall. So suddenly they had two completely conflicting warnings in the cockpit, one telling them they're overspeeding, and the other telling them they're about to stall and fall out of the sky.

Unfortunately they never figured out that they had a blocked static system and ended up crashing into the ocean.

Stuff like that is why you've always got to pay extra attention to any aircraft that just came out of maintenance or got washed. The mechanics usually do a good job and try to make sure they don't forget stuff like that, but the chances of something going wrong with the plane are usually a lot higher right after it comes out of maintenance.

WTE_Galway
09-19-2004, 06:02 PM
a good friend of mine lost all accessory power including instrument lights on a IFR night flight in overcast conditions in western NSW in an old Beech twin a few years ago

luckily he had a lighter in his pocket and was able to use that to check heading and aircraft attitude regularly .. he was very fortunate to get home

Bearcat99
09-19-2004, 06:59 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Eraser_tr:

Trusting your instruments and ignoring your body is actually what has brought down planes in the bermuda triangle, not aliens or ghost ships or anything like that. Gas trapped under the surface comes loose and rises into the atmosphere. because of the gas, the plane's altimiter reads that it is climbing. The pilots see this and pitch the nose down even though they are flying level. They are actually diving and their body feels it, but they ignore it because of the instruments. Thusly they nose dive into the water.

I by no means have any experience but in a case like that, I think you should trust your body. Instruments don't feel inertia. But if you are flying blind and don't feel anything with your body, trust the instruments.<HR></BLOCKQUOTE>

Actually in the case of flight 19 (The Avengers I think they were out of Pensacola in the triangle)one of the theories also is that he actually ignored his instruments and trusted his own instincts. He thought he was in the Gulf heading east but he was actually in the Atlantic heading to his death. Your senses will mislead you more than those instruments will however like in the case of the gas.. or the blocked tube.. there are always exceptions.

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WTE_Galway
09-19-2004, 07:52 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Eraser_tr:

I by no means have any experience but in a case like that, I think you should trust your body. Instruments don't feel inertia. <HR></BLOCKQUOTE>

absolutely completely and utterly wrong

the instruments DO feel inertia .. your inner ear does not, given a constant acceleration your body eventually "ignores it" the instruments do not

what you are saying goes completely against everything that is drummed into real world pilots from the very first day they start training

wayno7777
09-19-2004, 08:34 PM
Lindberg didn't even have a windshield. Flew mostly on instruments. His experiences on the crossing flight play right into this thread.

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Kefuddle
09-20-2004, 01:05 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>I by no means have any experience but in a case like that, I think you should trust your body. Instruments don't feel inertia.<HR></BLOCKQUOTE>
There is this statistic doing the rounds. A pilot untrained in the ways of instrument flight has, on avergae, 173 seconds to live once entering cloud. For you my fried, that number would be nearer 30 seconds! A cheap jibe but a crucial point.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> Gas trapped under the surface comes loose and rises into the atmosphere. because of the gas, the plane's altimiter reads that it is climbing. The pilots see this and pitch the nose down even though they are flying level.<HR></BLOCKQUOTE>
What a load of twoddle. Aside from the fact that the pressure change would have to be huge for an a/c at 10000' (a 513mb pressire change on average) and as such...suddenly there wouldn't be any cloud (and hence no problem). The gas would be convective pushing the a/c up. Even if it wasn't the ASI would off the scale as the a/c descends and the VSI would be climbing. I bet some of the a/c supposedly lost didn't have AIs.I think any idiot would start to wonder why they were reducing power constantly to maintain the same speed. Don't believe everything they say on the Discovery Channel http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

effte
09-20-2004, 07:10 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Eraser_tr:
Gas trapped under the surface comes loose and rises into the atmosphere. because of the gas, the plane's altimiter reads that it is climbing. The pilots see this and pitch the nose down even though they are flying level. <HR></BLOCKQUOTE>

As the gas rises it expands... to ambient pressure, hence no altitude change indicated. The lower density would mean you got a drop in indicated airspeed though. You would loose lift as well.

If the pocket was large enough to take any significant amount of time to cross (which it wouldn't be), you probably should consider what kind of gas the engines need to inhale to stay happy. And what might happen if they were to inhale methane instead...

TX-EcoDragon
09-20-2004, 02:26 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by effte:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Eraser_tr:
Gas trapped under the surface comes loose and rises into the atmosphere. because of the gas, the plane's altimiter reads that it is climbing. The pilots see this and pitch the nose down even though they are flying level. <HR></BLOCKQUOTE>

As the gas rises it expands... to ambient pressure, hence no altitude change indicated. The lower density would mean you got a drop in indicated airspeed though. You would loose lift as well.

If the pocket was large enough to take any significant amount of time to cross (which it wouldn't be), you probably should consider what kind of gas the engines need to inhale to stay happy. And what might happen if they were to inhale methane instead...<HR></BLOCKQUOTE>

I saw an interesting program on that . . . they created a theoretical methane pocket, and had it's properteis loaded into a Flight Simulator (as in Full motion, full flight deck) and the results were rather extreme. It seems rather silly and I thought it was a load of. . . well andyway, they also tested the engines, and they ran rather well at realistically possible concentrations of CH4. So it would have had to have been one monster bubble. . . but some of these researchers seem to think that a bubble that size is possible there. . .

hehe

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effte
09-20-2004, 03:44 PM
Knowing a bit about flight simulators, I'm not surprised that the results were outrageous. They're not designed to test hypothetical methane pocket scenarious so they won't. Ever see someone try to run performance checks in a simulator by the way? Out of envelope manoeuvers?

Heck, I even managed to find errors in the engine management in thirty minutes in the sim on a type I'm familiar with! http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

Cheers,
Fred

Buckaroo12
09-20-2004, 05:18 PM
Night Flying is a very tricky yet very enjoyable undertaking. The trouble with VFR night flying is the definition of VMC. In Canada VMC is defined as being able to fly free of cloud within X amount of miles horizontally and X number of feet vertically WITH REFERENCE TO THE GROUND. The problem with this definition is that on a moonless night if you see a single streetlight, that is legally reference to the ground and is reported as such. This is where it becomes extremely important to know your limits and remember JUST BECAUSE YOU CAN, DOESN'T MEAN YOU SHOULD! Out over Canada's prairies and vast stretches of bush, lighting from towns/farms/houses/etc. can be few and far between so you get the black hole effect on a night where the moon is gone or not quite strong enough to give you any light. You literally cannot with your eyes see the horizon or even the ground for that matter. This makes relying on your instruments and telling your sense of balance to take a hike critical.

Experience is no indicator of survival time, I have seen some statistics that would support the theory that experienced pilots with several hundred hours are maybe a little more susceptible to accidents then a guy fresh out of training. The reason being, the guy who just got out of training will realize that he is inexperienced and be extra careful (we hope) whereas the fellow that has his own airplane and flies it around every weekend is prone to be overconfident in his abilities and is maybe a little more likely to push the limits just a little too far.

I'm not sure what the requirements are for a night rating in other parts of the world, in Canada you must have a PPL and then recieve a total of 5 additional hours of instrument training and another 5 (I think, it's been a while!) hours of night training which includes x number of circuits as well as a small cross country trip. This would give the guy who did his night rating immediately after his PPL a mere 10 hours of instrument training. I don't think this is enough. Granted, on a nice full moon night where you're flying over towns and highways you will have no problem whatsoever. It is those "Black hole" nights over unsettled areas that will kill you. I personally think that making an instrument rating a pre-requisite for a night rating would be a really good idea. The majority of night flights with the current regulations still end successfully, but there's enough people out there who shouldn't go and make it on sheer luck to make me think that tightening the regs wouldn't be a bad idea.

I learned this lesson the hard way once and was one of those aformentioned lucky bastards. My wife and I had flown into Calgary to visit some friends for supper. It was early march and I had a brand new shiny night rating that I wanted to try out so we weren't in a rush to get home. As the evening progressed, I kept looking out the window at the ever lowering cieling. I called for a weather briefing and was told VMC conditions all across southern Alberta so I didn't sweat it too much, the weather guys are never wrong right? As we drove out to Calgary international (which is a lot of fun going to, waiting in line on the taxi-way in a cherokee in front of a 737!) I kept my eyes on the clouds and it didn't look like VMC to me so I checked again when I got into the FBO. The weather service again told me that there was no problem, clouds were 2000ft AGL. So I walked out, preflighted the plane and hopped in. Got another weather report from ATIS telling me I had VFR conditions over the city. Taxiing out, I kept looking up at this really low cieling but I thought "tower would never even clear me to the runway if it wasn't VFR out there". Sitting on the hold short line, Tower gives me my clearance to take position and I re-emphasize just to be safe that I am VFR southbound. They confirm me as filed for VFR for Lethbridge and the flight plans open as they clear me for take-off. Putting complete faith in the tower, I hit the throttle and the mighty cherokee starts like greased lightening down the runway. I rotate, lift-off, climb 300 ft and all of a sudden everything disappears in a grey haze. I got on the radio to tower after checking my instruments to maintain my climb and informed them that I had lost visual reference to the ground and everything else (trying to keep the panic out of my voice) They asked me what I wanted to do, they had PIREP's claiming CAVU 25 miles south of the city, was I comfortable enough with my instruments to fly through the soup while they gave me vectors to clear air? They were really really good about it and kept talking to me throughout the entire time (even after I was past their control zone) until I was into the clear and safely on my way home. As green as I was, I realize that if I hadn't had someone talking me through everything that night I probably would've ended up in the safety bulletins. I realize that I flew into the clouds that night and it's not really what the subject is about, but the result is the same wether you fly into clouds accidentally or have a black hole night. Either way, you can't see anything with your eyes and if you don't know enough to rely on your instruments you had better hope that the man upstairs is looking after you. When I lost sight, it took every ounce of willpower in my body to accept that my brain was trying to kill me and that I really should believe in my instruments. Now, after several years and a lot more experience, the struggle is still the same every time. It is easier to ignore my brain but the conflict is still there.

El Turo
09-20-2004, 05:58 PM
Buckaroo.. great (scary) story!

About the only thing even remotely close to that was when I got cleared (similarly) to go on a VFR cross country when I was REAL green and low on clock hours.. only to be face to face with a seriously hard core rainstorm just 5-10 minutes after liftoff and confirming scattered/broken with weather service and tower. They had said that I might get a little bit of precipitation but that it wouldn't be a big deal as light as it might be. Well, let me tell you.. it wasn't a thunderstorm, but it was kicking my *** something fierce for a minute or two without relenting and was really freaking me out with nearly zero visibility.. so I did what my instructor had told me previously and that was to do a quick 180 and haul *** back home, outrunning the storm. I maintained a nice shallow dive and kept humming along at about 120-130kts the whole way home.

That was not fun at all, but good to know that we're capable of getting through such bad situations unscathed.

Since, I've made it most of the way through my instrument and commercial training (combined syllabus) so such a situation wouldn't be that bad to me now.. but at the time (being fairly green) it was pretty dammed scary!

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WTE_Galway
09-20-2004, 06:07 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Buckaroo12:
You literally cannot with your eyes see the horizon or even the ground for that matter. This makes relying on your instruments and telling your sense of balance to take a hike critical.

Experience is no indicator of survival time, I have seen some statistics that would support the theory that experienced pilots with several hundred hours are maybe a little more susceptible to accidents then a guy fresh out of training. The reason being, the guy who just got out of training will realize that he is inexperienced and be extra careful (we hope) whereas the fellow that has his own airplane and flies it around every weekend is prone to be overconfident in his abilities and is maybe a little more likely to push the limits just a little too far.
<HR></BLOCKQUOTE>

Statistically the most dangerous time is between 100 and 500 hours logged time. It seems like at that point in hteir flying career many people get overconfident, they are no longer nervous but have not had any serious "scares" yet to knock the cockiness out of them.

Fred_77
09-20-2004, 08:27 PM
A link to the above mentioned 178 seconds to live article.

http://www.faa.gov/fsdo/fll/178sec.htm

Describes a pretty typical graveyard spiral.

P.S. Relying on your instincts or "the Force" in IMC is a guaranteed death. Trust your instruments, they are there for a reason.

S!
Fred.

[This message was edited by Fred_77 on Mon September 20 2004 at 07:41 PM.]

darkhorizon11
09-20-2004, 09:54 PM
How did World War Two pilots respond to this? I noticed that a lot of planes (using FB as a reference) don't have Attitude Indicators in them. I assume that with the little experience many pilots had there must've been a decent amount of accidents...

WTE_Galway
09-20-2004, 10:08 PM
you can fly IFR with only altimeter airspeed and turn and bank .. but its not easy

here are some interesting RL anecdotes:

http://www.omen.com/f/sd.html

strongly suggest anyone that believes you should trust your "intuition" over the instruments reads it right through http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

Buckaroo12
09-20-2004, 10:22 PM
El Turo,

I can guarantee from personal experience that a thunderstorm isn't an experience you will ever want to repeat again. Last summer, I was up in the north (my second home). I was flying a 180 on floats with 2 hunters and some of their moose on board. Whipping along through the mountains, it was overcast but not terrible out so I took a short-cut through a fairly narrow valley and came out at the other end right into a small thundershower. You want to talk about getting the cr@p beaten out of you in the air. I had no room to turn around and the only other exit was right through it. I'll tell you what, nothing grabs your attention like a 2000 ft/min downdraft in the mountains. It wasn't even a big storm, that's the joy of mountain flying. Unless you can climb over top, you have no idea what's around the next corner! Wouldn't trade it for a minute though!!!

Jungmann
09-21-2004, 08:30 AM
Darkhorizon:

I remember reading about plenty of stall/spin accidents with S/E AAF aircraft climbing out of their English bases to form-up through nasty weather. AAF pilots got very little instrument time in their Stateside training. The Brits got more, and so were better at flying on the clocks. As I remember, the rash of accidents prompted an increase in hood time for AAF trainees in the latter part of the war.

And all these aircraft had artificial horizons (attitude indicators).

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Ashoka74
09-21-2004, 09:31 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Buckaroo12:
El Turo,

I can guarantee from personal experience that a thunderstorm isn't an experience you will ever want to repeat again. Last summer, I was up in the north (my second home). I was flying a 180 on floats with 2 hunters and some of their moose on board. Whipping along through the mountains, it was overcast but not terrible out so I took a short-cut through a fairly narrow valley and came out at the other end right into a small thundershower. You want to talk about getting the cr@p beaten out of you in the air. I had no room to turn around and the only other exit was right through it. I'll tell you what, nothing grabs your attention like a 2000 ft/min downdraft in the mountains. It wasn't even a big storm, that's the joy of mountain flying. Unless you can climb over top, you have no idea what's around the next corner! Wouldn't trade it for a minute though!!!<HR></BLOCKQUOTE>

Umm, I suppose you didn't tell your mom, heh? http://ubbxforums.ubi.com/images/smiley/59.gif

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El Turo
09-21-2004, 09:49 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Buckaroo12:
El Turo,

I can guarantee from personal experience that a thunderstorm isn't an experience you will ever want to repeat again. Last summer, I was up in the north (my second home). I was flying a 180 on floats with 2 hunters and some of their moose on board. Whipping along through the mountains, it was overcast but not terrible out so I took a short-cut through a fairly narrow valley and came out at the other end right into a small thundershower. You want to talk about getting the cr@p beaten out of you in the air. I had no room to turn around and the only other exit was right through it. I'll tell you what, nothing grabs your attention like a 2000 ft/min downdraft in the mountains. It wasn't even a big storm, that's the joy of mountain flying. Unless you can climb over top, you have no idea what's around the next corner! Wouldn't trade it for a minute though!!!<HR></BLOCKQUOTE>

Yikes.

Yeah.. that'll make the boys run for cover, that's for sure!

http://ubbxforums.ubi.com/infopop/emoticons/icon_eek.gif

I'd love to get my float rating and run hunters/fishermen up into the mountains. Do you make a living with it or just on the side? I've often thought of giving up my nice job to go fly and be poor, but I have some conflicting morality issues due to having a family as well and dunno if it would be fair to them.

=/

Oh, to fly every day and be free! There's just nothing like flying in the morning with broken clouds and sunbreaks.

Bleh.. and here I am flying a desk instead.

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______________________
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I thought,
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Buckaroo12
09-21-2004, 10:58 AM
Nope, didn't tell my mom!
I'm trying to make a full time living at it, but it sure is tough. I'm at the borderline right now where I have some experience, but not enough to guarantee jobs all the time. It's taken its toll on my family and this summer was one of those bad ones that make a guy think about changing careers while he's young enough to do something else. If you've already got a good job, save your pennies and fly for fun is my recommendation.