Instrument flying; how important is the Attitude Indicator?
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"Please correct me if I'm wrong; the AH is not a required instrument legally for DayVFR?"
Not under operational rules in Europe or Canada, but there may be engineering rules that require it - a 212 guy got caught out by that in Canada.
Phil
Not under operational rules in Europe or Canada, but there may be engineering rules that require it - a 212 guy got caught out by that in Canada.
Phil
Jim, some of that might be due to the prevalence of glass cockpits, since the old selective radial scan, where you had to move your head to encompass all the analogue instrument scattered across the cockpit, can now be replaced by a 'big picture' type scan where the PFD only requires a fixed gaze at the attitude with the remainder being picked up on peripheral vision.
Hi Crab,
Yes, that is correct but the 'heat maps' provided by the eye-tracking system did not even include the horizon for some of the pilots. There must be a reason, and that reason should be understood because it might require an adjustment in the configuration of the screen or more education on the the optimum scanning pattern (do we educate pilots on the necessary scanning pattern for glass screens? do we specify, precisely, what should be monitored by the PF or the PM when hand flying? Is there an optimum distribution of the monitoring duties of each of the pilots when the autopilot is engaged?) All questions that should not go unanswered.
The comment was made at the conference that if neither pilot included the horizon within the scan, a critical departure from the flight path could occur and might be missed.
If there is a difference in the required scanning patterns between a stable fixed-wing and an unstable helicopter, what does that imply?
Jim
Yes, that is correct but the 'heat maps' provided by the eye-tracking system did not even include the horizon for some of the pilots. There must be a reason, and that reason should be understood because it might require an adjustment in the configuration of the screen or more education on the the optimum scanning pattern (do we educate pilots on the necessary scanning pattern for glass screens? do we specify, precisely, what should be monitored by the PF or the PM when hand flying? Is there an optimum distribution of the monitoring duties of each of the pilots when the autopilot is engaged?) All questions that should not go unanswered.
The comment was made at the conference that if neither pilot included the horizon within the scan, a critical departure from the flight path could occur and might be missed.
If there is a difference in the required scanning patterns between a stable fixed-wing and an unstable helicopter, what does that imply?
Jim
One of the classic student mistakes in IF is 'instrument chasing' where any one or two instruments are concentrated on to the detriment of the AI - it is obvious to the instructor and will inevitably end up with inaccuracies or unusual attitudes as the task gets more demanding.
A good instrument pilot will base his scan around the AI but we all get lazy sometimes, especially when the workload and arousal levels are low.
When things get gnarly then it is those with the AI centered scan who will retain accuracy and safety and the instrument chasers will probably scare themselves.
Despite VF's dismissal of its value, the use of the AI for mountain flying has long been taught in the UK mil - perhaps because the skills learned from a visual/IF balance are even more important when you fly the mountains at night.
A good instrument pilot will base his scan around the AI but we all get lazy sometimes, especially when the workload and arousal levels are low.
When things get gnarly then it is those with the AI centered scan who will retain accuracy and safety and the instrument chasers will probably scare themselves.
Despite VF's dismissal of its value, the use of the AI for mountain flying has long been taught in the UK mil - perhaps because the skills learned from a visual/IF balance are even more important when you fly the mountains at night.
Hey Crab.....I hear You Mate, I'm not negating the value of an AH, for IMC & for NVMC it is a life saving necessity. Wouldn't leave home without it!!! 
For DayVMC under VFR in the Mountains it is a distraction from looking outside if Pilots wanna be chasing it & in these unique conditions eyes outside is where You wanna be, to stay safe
Heaven forbid, I'd never wanna be up in these Mountains at night
Happy Landings
For DayVMC under VFR in the Mountains it is a distraction from looking outside if Pilots wanna be chasing it & in these unique conditions eyes outside is where You wanna be, to stay safe
Heaven forbid, I'd never wanna be up in these Mountains at night
Happy Landings
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VF - surely you must scan the AI from time to time even when you are VMC, because there must be a lot of the time you dont have a natural horizon in your environment? (In that a level horizon is rarely visible unless you are above all that massive terrain)
Originally Posted by [email protected]
Jim, some of that might be due to the prevalence of glass cockpits, since the old selective radial scan, where you had to move your head to encompass all the analogue instrument scattered across the cockpit, can now be replaced by a 'big picture' type scan where the PFD only requires a fixed gaze at the attitude with the remainder being picked up on peripheral vision.
Going way OT here from the OP.
Avoid imitations
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On the subject of pilots being put under pressure to fly, here in Ireland we had a recent controversy when a senior Government Minister pressurised an Air Corps pilot to fly when fog was forecast. And to compound the matter his representative phoned up the pilot again to 'rub it in' when the fog didn't materialise. Varadkar defends Coveney?s call to pilot over cancelled flight
The Minister's excuse was "I'm a 'hands on' type of guy". You couldn't make it up.
The Minister's excuse was "I'm a 'hands on' type of guy". You couldn't make it up.
I've also been called a "jobsworth" to my face when insisting I stuck to the regulations when using a private landing site (no ops after dark, the passenger wanted to come back well after last light).
And I've been called a "chicken" by the owner of a listed building when I decided not to land in his confined area of a garden because it was downwind in 25-30 kts of wind. Flying into wind to land to get in there would have involved very low flight over his house roof and would probably have lifted tiles or worse.
You do need broad shoulders for this job.
Agree, but surely 'move your head' is a typing error. Instrument scan should be eye movements only whether radial or orbital, head moves can start vestibular canal upsets; the occasional glance over to Ts & Ps on a large cockpit panel should be the only conscious head movement.
Avoid imitations
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Originally Posted by [email protected]
You could do that on a Gazelle but the Wessex, Lynx and Sea King all required some head movement to scan the instruments, especially if you were on standbys.
We'll have to agree to disagree.
But we do agree that the AH is a primary instrument for IFR
Last edited by John Eacott; 14th Jul 2017 at 01:45. Reason: Add Wessex panel
Hey Non-PC Plod.....Brother the DayVFR machines have no requirement to have the AH serviced to an IF standard, they topple often & are just not reliable. I wouldn't trust them. As SuperF mentioned many NZ machines have no AH & fly in the Mountains! Rarely am I above the massive terrain so the technique I was taught by Grand Master Mountain Pilots is that Your attitude is determined by Your Airspeed which is based on the stick position, I was taught You don't look at the horizon to determine speed nor attitude, wouldn't work very well here surrounded by these hills anyways, only the IAS. So You could say my AH is actually my IAS this method has been working fine thus far
AH sure is the primary instrument for IFR & NVFR = YES
Cheers it's beer o'clock
this method has been working fine thus far AH sure is the primary instrument for IFR & NVFR = YES
Cheers it's beer o'clock
VF - the problem I have with that technique is that your attitude will tell you what is about to happen to the speed whereas the IAS only tells you where it is at that moment in time.
You must end up constantly chasing speed with cyclic movement, especially in gusty conditions.
Attitude for airspeed, lever for height
John - I think you might have moved your head a bit more than you think - its not a lot, and not enough to cause vestibular issues, but I think it is unlikely that your head remained absolutely still during your scan.
You must end up constantly chasing speed with cyclic movement, especially in gusty conditions.
Attitude for airspeed, lever for height
John - I think you might have moved your head a bit more than you think - its not a lot, and not enough to cause vestibular issues, but I think it is unlikely that your head remained absolutely still during your scan.
G'day Crab........really I don't have a problem with this technique & Mountain Pilots I know also don't, it works. I am not chasing an airspeed. The stick is fixed to the side of the thigh & politely holds the airspeed exactly where I want it leaving most of my time with eyes outside rather than staring at the AH which in this part of the World not maintained so cannot be relied on?
Cheers
Cheers
Thread Starter
In the way of War Stories....re instrument flying in helicopters I have this to offer.
As part of my US Army Helicopter Instrument flying course at that wonderful Alabama Resort area known as Fort Rucker....using Huey's....we at some point had to enjoy a flight into Knox Heliport by executing an NDB Approach with overhead Hold.
Piece of cake right.....No Gyros, Fixed Card, unstablized single engine helicopter with no RadAlt.
That it was in IMC proved to me my Instructor was near suicidal and had real intent to take two others with him in the process.
That it was I doing the flying....is what convinced me of that.
Artificial Horizons are very nice kit...and have their uses....but they in my definition (if not in the usual context/definition) are "Secondary" instruments.
I am of the school.....that a single Attitude Indicator is a necessity but a Backup is pure Gold should the first one lay down on you while in IMC conditions.
A test I used while Instructing Instrument Flight.....was to use Unusual Attitude Recovery Exercises to determine what technique the Trainee used for controlling the aircraft.
I did the usual, Head down, Eyes Closed, wiggle the sticks all about and add some varying kinds of G Loads.....but that was just to disguise my setting a Five Degree wing low attitude on the Student's Attitude Indicator without being seen.
Then I gave control back while in a very minor non-level, out of yaw trim condition and sat back and observed the recovery to level flight.....and in some cases could have run out fuel waiting for that to happen.
Some Pilots very quickly sorted out the Attitude Indicator was out of whack as they were flying the other instruments and using the AI as a Reference. They would set wings level, pitch attitude level....and then correct for the resulting variation and in a cycle or two....perhaps three...sorted it out.
Others....as mentioned NEVER would have gotten settled down.
As to moving one's Noggin about while "Scanning"....in the scenario above....looking at the Standby...and other Pilot's AI worked well too.
Just looking at two AI's....each showing something different...does not immediately tell you which one is the liar.
In some of the Accident Reports we read about now and then where airliners smack the ground at warp speed because of a loss of control due to instrument failure...it makes you wonder why the crew with at least three AI's could not sort out the problem very quickly.
As part of my US Army Helicopter Instrument flying course at that wonderful Alabama Resort area known as Fort Rucker....using Huey's....we at some point had to enjoy a flight into Knox Heliport by executing an NDB Approach with overhead Hold.
Piece of cake right.....No Gyros, Fixed Card, unstablized single engine helicopter with no RadAlt.
That it was in IMC proved to me my Instructor was near suicidal and had real intent to take two others with him in the process.
That it was I doing the flying....is what convinced me of that.
Artificial Horizons are very nice kit...and have their uses....but they in my definition (if not in the usual context/definition) are "Secondary" instruments.
I am of the school.....that a single Attitude Indicator is a necessity but a Backup is pure Gold should the first one lay down on you while in IMC conditions.
A test I used while Instructing Instrument Flight.....was to use Unusual Attitude Recovery Exercises to determine what technique the Trainee used for controlling the aircraft.
I did the usual, Head down, Eyes Closed, wiggle the sticks all about and add some varying kinds of G Loads.....but that was just to disguise my setting a Five Degree wing low attitude on the Student's Attitude Indicator without being seen.
Then I gave control back while in a very minor non-level, out of yaw trim condition and sat back and observed the recovery to level flight.....and in some cases could have run out fuel waiting for that to happen.
Some Pilots very quickly sorted out the Attitude Indicator was out of whack as they were flying the other instruments and using the AI as a Reference. They would set wings level, pitch attitude level....and then correct for the resulting variation and in a cycle or two....perhaps three...sorted it out.
Others....as mentioned NEVER would have gotten settled down.
As to moving one's Noggin about while "Scanning"....in the scenario above....looking at the Standby...and other Pilot's AI worked well too.
Just looking at two AI's....each showing something different...does not immediately tell you which one is the liar.
In some of the Accident Reports we read about now and then where airliners smack the ground at warp speed because of a loss of control due to instrument failure...it makes you wonder why the crew with at least three AI's could not sort out the problem very quickly.
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SAS;
I spent most of my early career two crew, there was a natural tendency to turn slightly towards your colleague when everything was relaxed. It was brought home to me by a very senior training captain when he pointed out that I had just flown 80% of a solid IFR trip looking at his instruments. I had never noticed that habit forming.
A few weeks later I had an FD failure on my side which took some time to notice because my attention was on the other side. Now I fly a mix of single and multi crew, and age has set in, but I very much agree with you, while the AI has the primary function, if you don't have speed and altitude nailed the AI can be letting you down very subtly and steering you to a whole can of worms.
SND
I spent most of my early career two crew, there was a natural tendency to turn slightly towards your colleague when everything was relaxed. It was brought home to me by a very senior training captain when he pointed out that I had just flown 80% of a solid IFR trip looking at his instruments. I had never noticed that habit forming.
A few weeks later I had an FD failure on my side which took some time to notice because my attention was on the other side. Now I fly a mix of single and multi crew, and age has set in, but I very much agree with you, while the AI has the primary function, if you don't have speed and altitude nailed the AI can be letting you down very subtly and steering you to a whole can of worms.
SND