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Old 15th Jul 2017, 08:44   #41 (permalink)
 
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Recovery without using the AI was standard when I was taught to fly on instruments. The reason was simple; it was vacuum driven and when it reached 60 degrees of pitch or bank it hit the internal stops, got lost and toppled. Until manually re-erected it just waved woefully as it drifted from stop to stop.

You learnt to recover, even from spins, using limited panel; airspeed, rate of turn, RCDI and altimeter. Firstly in radial engine fixed wing and then later, without the spins, in radial engine helicopters but you wouldn't catch me trying to fly IMC with just an AI.
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Old 15th Jul 2017, 14:22   #42 (permalink)
 
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The AI is the primary instrument not the only one hence the selective radial scan where you adjust the attitude and then scan the other instruments to see if it has the desired effect.

Just how do you recover from an unusual attitude in a helo without reference to the AI? Wings level has to be the first action to prevent further problems and you cross check with the standby AI to make sure the main hasn't toppled and got you into the UA/UP in the first place.

Sasless' trick of offsetting the pilots AI during the positioning for the UP/UA has been used for many years to the great amusement of many QHIs and IREs
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Old 15th Jul 2017, 15:29   #43 (permalink)
 
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Crab

The two guys who set up the first Sea King sim back in 1970 (Test pilot Peter Harper and Jet Jock Peter Jago) did a lot of work on the question of scanning. It was before the technology to track eye movement was available so each would spend time lying on the interseat console whilst monitoring the pilot flying's eye movement. They were astonished to find that experienced pilots used peripheral vision to a far greater extent than previously realised.

The problem with today's flats screen digital displays is that many pilots coming from older generation helicopters have a huge problem with re-programming the brain to look, recognise, calculate and respond because with peripheral vision the brain relies on the needle position on a dial. No dial, no needle, just a number and your scanning process has to be modified as well as reprogramming your brain to deal with numbers.

G
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Old 15th Jul 2017, 16:16   #44 (permalink)
 
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Hi geoffers - yes I have found the same thing in transitioning to PFDs from analogue instruments - in particular the tape for the altimeter is almost a constant stream of numbers and, unless you have a DA line on your desired altitude, it is much easier to miss a deviation than with an altimeter needle moving round a clock face.
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Old 15th Jul 2017, 16:50   #45 (permalink)
 
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Crab;

If the altimeter is a continuous stream of numbers might I respectfully suggest a few sessions on effects of controls and secondary effects from Jellycopter....................................

SND
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Old 15th Jul 2017, 20:11   #46 (permalink)
 
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The problem with today's flats screen digital displays is that many pilots coming from older generation helicopters have a huge problem with re-programming the brain to look, recognise, calculate and respond because with peripheral vision the brain relies on the needle position on a dial. No dial, no needle, just a number and your scanning process has to be modified as well as reprogramming your brain to deal with numbers.
Yes, I would often trim the cyclic the wrong way when trying to adjust the airspeed by a few knots when on instruments.
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Old 15th Jul 2017, 22:29   #47 (permalink)
 
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Gosh - cyclic trim! You were a lucky bunny to have that luxury.......
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Old 16th Jul 2017, 01:16   #48 (permalink)
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As a US Army Instructor Pilot....I learned to fly the Student's Instruments when performing a demonstration of a maneuver as that is what he was looking at while you did the Demo.

In some cases you had to use an index at the side of an instrument rather than the top as you could not see the normal index.

With a bit of practice it became quite normal to do that.
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Old 16th Jul 2017, 01:16   #49 (permalink)
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As a US Army Instructor Pilot/Standardization Pilot....I learned to fly the Student's Instruments when performing a demonstration of a maneuver as that is what he was looking at while you did the Demo.

In some cases you had to use an index at the side of an instrument rather than the top as you could not see the normal index.

With a bit of practice it became quite normal to do that.
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Old 16th Jul 2017, 08:14   #50 (permalink)
 
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Yes Sasless - the same applied on Wessex, Lynx and Sea King
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Old 16th Jul 2017, 15:41   #51 (permalink)
 
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AI is 'GOD' - for at least 90% of the time whilst IF and without AP.
Never forget my first instructor teaching me the radial scan by saying if you are not looking at the AI then you should be - helped me return my gaze back to the middle before something ugly happened!
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Old 16th Jul 2017, 18:56   #52 (permalink)
 
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?.......helped me return my gaze back to the middle before something ugly happened!
EESDL, I think something ugly happened about 20 years before that, and I blame your parents!
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Old 17th Jul 2017, 00:35   #53 (permalink)
 
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warning - Thread Drift.....

j(c)
When my parents eventually owned-up to having raised me they said I was a result of 'immaculate conception' - some carpenter dude was in town at the time.
How is your garden furniture holding up?
;-)
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Old 17th Jul 2017, 11:40   #54 (permalink)
 
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Basic rule for both VFR or IFR flying is: Attitude + Power = Performance. Which also can be seen as: Natural or Artificial Horizon + Power Gauge = Flight Instruments. In more detail that will be: Pitch and Bank + Power Gauge = Altimeter/Airspeed Indicator (primary for pitch) and Compass/Directional Gyro/Turn Indicator (primary for bank) + known corresponding Airspeed/Climb Rate (vs. selected power). When left and right is not equal there is something wrong. Crosscheck for the fals one. All instruments are supporting, do not rely on a sole one.

Flying explained by the hand of mathematics, ain't that exciting ;-)

Last edited by Anywing; 17th Jul 2017 at 12:13.
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Old 17th Jul 2017, 21:23   #55 (permalink)
 
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AI is 'GOD' - for at least 90% of the time whilst IF and without AP.
Never forget my first instructor teaching me the radial scan by saying if you are not looking at the AI then you should be
Interesting discussion, especially the Army guys talking about de-emphasizing the attitude indicator.

When I learned to fly instruments in the early 90s there were a lot of vacuum pump failures happening (I think the technology of the vacuum pumps had changed from wet to dry and the technology wasn't solid yet). So, as a dumb student, I evolved this rather stupid idea that I would de-emphasize the AI, and in that way I wouldn't lose control when I lost vacuum (of course, this is in airplanes, all the helicopters I've flown were all electric AI).

The thing was, I flew lousy on instruments.

Having flown with some very experienced airline pilots I eventually realized the folly and finally put major emphasis on the attitude indicator. No surprise that suddenly my IMC flying got much better. My only regret is that we don't have giant attitude indicators like airliners used to have! Or at least, the IFR B206L3 I fly doesn't. I just put on my old man reading glasses and lean closer to make the AI appear bigger ;-)

I recently had a discussion of Control and Performance (which I teach) versus Primary and Supporting with the senior fixed wing instructor at our school. I was really surprised that he talked about liking Primary & Supporting and de-emphasizing the attitude indicator so that loss of AI is a non-issue. He's non-military, and a very good instructor, but I didn't find his arguments convincing. I'm still of the opinion that using the AI allows you to make extremely small corrections and therefore fly extremely accurately. Perhaps it's the difference of flying electric AIs - I don't worry as much about a loss of control from an AI going bad (you pick it up pretty darn quick in the cross check).

One thing I always carry with me is one of those rubber instrument covers that we torture our students with. The reason I carry it with me is that I find it very difficult to ignore an AI which has failed. I'm so used to the scan that every time I return to the AI (that has "failed") I start to roll/pitch to correct before I remember that the AI is bad. So, I cover it up and that forces me to use the standby (which is just left of the six-pack).

On the humorous side, I've heard the scan called a "music scan" because you should keep a pace of scan going "and-a-one, and-a-two" each time you leave one instrument for the next instrument in the scan. I'm old enough to remember my grandparents watching Lawrence Welk (an American band leader with a distinctive German/European accent), so that whenever I'm instrument flying I hear Lawrence Welk inside my head!
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Old 18th Jul 2017, 00:02   #56 (permalink)
 
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My only regret is that we don't have giant attitude indicators like airliners used to have!
We do! (Although not electromechanical like airliners used to have.) This and similar avionics suites now available in several certified light turbine (VFR only) singles, including B505, E480B-G, R66 (in a less complete form), Agusta 119, B407GXP, and others coming. Typically include synthetic vision, HTAWS, ADS-B In & Out, active traffic sensor, Nexrad wx, geo-referenced approach plates, and other capabilities, and in some cases, an autopilot capable of flying coupled approaches. In the case of the 505 and 407GXP, there is no longer a standard steam gauge option. However, slow in coming to the helo world. In the fixed wing world, this equipment has been available in even the Cessna 172 for 10+ years. As an instrument rated pilot for almost forty years, after flying this setup for the last three years, I have no desire to return to the good old days!

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Last edited by EN48; 18th Jul 2017 at 14:56.
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Old 18th Jul 2017, 00:37   #57 (permalink)
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I would feel like a Dog watching Television if I had a panel like that to look at.
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Old 18th Jul 2017, 00:44   #58 (permalink)
 
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I would feel like a Dog watching Television if I had a panel like that to look at
Well ... it doesn't do TV, but it does have SiriusXM radio/music for the dog's listening pleasure. You can listen to Rush while you fly!

Last edited by EN48; 18th Jul 2017 at 00:59.
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