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Couple observations on real life IFR

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I just completed the last of my simulator rides for instrument approaches. We covered both ILS and GPS approaches in this 2hr flight. Because the session had to go long (I needed 1.9hrs for course requirements), we were done with the official requirements early so we tried an experiment.I read on avweb.com an article considering what actions a pilot should take if both vacuum and electrical failures occur in flight. This means that not only are heading indicator and attitude indicator are not available, but also the turn coordinator for basic attitude flight and the entire radio/nav stack for navigation and communication. Note that a vacuum failure should be a non-event if the instrument pilot is trained to fly the "primary-secondary" method of basic attitude instrument flight where an attitude indicator is relegated further back in importance in the instrument scan ("control-performance" types could have trouble). Of course backup equipment like electrical vacuum is disregarded in this scenario.But losing the TC means that only the cantankarous compass is available for turn and bank information. One can no longer use timed turns to figure out what heading one will be on. There is a way of calculating where to roll level on a particular heading (and believe me it takes a pretty fair share of brain-time to do the math in your head), but it still helps to have an attitude indicator telling you when you're level. The strategy at this point is pure survival and that leads me to the experiment:First my CFII failed both systems and drained the battery at max speed (took too long so he just plain failed the TC), I attempted to control the airplane normally via compass and the pitot-static instruments I had left. I went into a graveyard spiral and died within 5 minutes. Second time around I *let go of the yoke* and steered with rudder only, using pure trim for vertical control. I also turned to 180 degrees since the compass offers immediately accurate turn information on that heading (if you're in Australia, I suggest 360). I broke out my VFR sectional and scanned for terrain and obstacle information south of my last known position. Then I started a 500fpm descent controlling direction with my feet only. I broke out at ~300 feet and did a scud run back to the airport with fields selected along the way for a possible precautionary/forced landing. I lived.So it is doable and one need not tuck their head between their legs in an emergency like this and wait to die. Also, as the author of the Avweb article noted, one should also not simply assume that nothing like this will happen simply because it is a remote chance and there are backups (battery f/10-15minutes, electric vacuum).The second observation is purely from a human factors standpoint. I screwed up on my last practice ILS approach and my CFII failed the glideslope. Of course I failed to noticed the flag and flew a perfect glideslope all the way down to DH. Sad. I'll wager I've gotten so used to seeing that flag during localizer/VOR navigation that it just didn't register. Though it is my fault, I wonder whether it wouldn't be better if the GS needle should default to full scale deflection when off (the VOR/LOC needle would still center). That way a GS failure on approach would immediately be noted since full scale deflection at any time warrants a missed approach. It's a little like designing other counter-intuitive controls such as a flap switch that extends the flaps when you push it up. Any thoughts?Bedwyr

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>The second observation is purely from a human factors standpoint. I screwed up on my last practice ILS approach and my CFII failed the glideslope. Of course I failed to noticed the flag and flew a perfect glideslope all the way down to DH. Sad. I'll wager I've gotten so used to seeing that flag during localizer/VOR navigation that it just didn't register. Though it is my fault, I wonder whether it wouldn't be better if the GS needle should default to full scale deflection when off (the VOR/LOC needle would still center). That way a GS failure on approach would immediately be noted since full scale deflection at any time warrants a missed approach. It's a little like designing other counter-intuitive controls such as a flap switch that extends the flaps when you push it up. Any thoughts?

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>Never, never rely on one piece of nav aid without using >seperate means of cross checking it. >>Hence on an ILS approach you will of course be studying your >approach plate and checking the glideslope against published >altitude/height points on the chart. >>Ie as you pass a marker or a fix you will be able to check >that your glideslope matches the altitude/height given at >that fix on the chart using your altimeter. >>Peter Ironically, that was his point. We'd gone through a whole mush of things and had only a few minutes left so we crammed this last one in a hurry (I had my first two approaches bang on). Because we were in a rush on this one, I decided not to load the approach into the GPS so I had no DME information (dual garmin, DME comes off GPS). I should've reset the timer for my backup. 3:44 down to DH @ 90kias. Like I said, it was my fault on that one and he caught it. Bad airmanship on my part. One other note, the ILS only has OM for FAF and MM at essentially the DH, so timing is the only option on this one.But what are your thoughts on the construction of the instrument? I still probably wouldn't have noticed the bad glide slope indication which prescribes an automatic missed approach (granted, I still should've been looking but this is a question with a larger scope).Bedwyr

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BedwyrWe are only human and mistakes are made when we are overconfidant or overpressurised.Aircraft/navaid builders still concentrate on flags, bells, whistles alarms to warn pilots.For example I know of one guy who has landed wheels up on not one but two occasions ignoring the audable warnings.The Citation Five I flew concentrated much more on voice warnings and these surely must be the way to go.There is no mistake if you forget the gear and a voice bellows "Gear, Gear, Gear"."GlideFail GlideFail Glidefail" cant be missed or mistaken.CheersPeter

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>Bedwyr >>We are only human and mistakes are made when we are >overconfidant or overpressurised. >>Aircraft/navaid builders still concentrate on flags, bells, >whistles alarms to warn pilots. >>For example I know of one guy who has landed wheels up on >not one but two occasions ignoring the audable warnings. >>The Citation Five I flew concentrated much more on voice >warnings and these surely must be the way to go. >>There is no mistake if you forget the gear and a voice >bellows "Gear, Gear, Gear". >"GlideFail GlideFail Glidefail" cant be missed or mistaken. >>Cheers >>Peter That was almost my question. :) What I was thinking was that having a flag (which is definitely fine) *combined* with a full deflection would be more noticeable than just the flag alone. I'd take what you have/had but considering the cost and weight addition of GPWS to a Warrior, well, maybe this would work.I'm wondering whether this is one of those ideas no one ever considered (or left alone due to bureaucratic inertia) or whether there's a darn good reason a failed or 'off' instrument always goes to CDI center in the same sense that a partial CDI deflection on GPS is required before use.I agree, btw, that dummy bells create the least attention division and probably are the way to go. Hope it shrinks and filters down to the smaller GA craft.Bedwyr

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