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#11
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Big John writes:
Sidney. All of the above G The approach plate gave the time to field in minutes and seconds listing several speeds to accommodate all the aircraft in inventory. Normally max time would only be 3-4 minutes and normally just 1-2 minutes after crossing cone of silence. You rarely landed straight in and many of the headings to field were not lined up with a runway. After sighting the field you would circle and land on the active runway. If you were in radio contact with the field/tower you could get surface wind and compute a ground speed from cone of silence to field, other wise you made a WAG from forecast and what you encountered en route. This does not sound a lot different from a typical NDB approach today, when the NDB is off the field. All the best, David -- David Megginson, , http://www.megginson.com/ |
#12
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David
Wasn't, except you normally didn't have the option of tracking outbound (on beam) from cone of silence like you can with ADF on a NDB after station passage. You flew a heading and time for distance. Think back on those days and shudder G Big John On Mon, 14 Jul 2003 12:14:01 GMT, David Megginson wrote: Big John writes: Sidney. All of the above G The approach plate gave the time to field in minutes and seconds listing several speeds to accommodate all the aircraft in inventory. Normally max time would only be 3-4 minutes and normally just 1-2 minutes after crossing cone of silence. You rarely landed straight in and many of the headings to field were not lined up with a runway. After sighting the field you would circle and land on the active runway. If you were in radio contact with the field/tower you could get surface wind and compute a ground speed from cone of silence to field, other wise you made a WAG from forecast and what you encountered en route. This does not sound a lot different from a typical NDB approach today, when the NDB is off the field. All the best, David |
#13
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Sydney Hoeltzli wrote
What do you think of the conclusions? They seem to be: 1) prevent AIs from failing Well, there's a lot to be said for that. For one thing, it's far from unlikely that BOTH of the AI's failed, not just one. Did you miss this: (All quotes from the referenced report) "These 21 artificial horizons had an MTBUR of 257 hours." That's mean time before unscheduled replacement, but... "The artificial horizon fitted to the EMB-110had no specified overhaul life and was treated as an 'on condition'item" and thus all replacements were unscheduled. Why was such a shockingly high failure rate tolerated? Well, "The BCAR Section under which the aircraftwas certificated did not stipulate the reliability requirementsthat the artificial horizon should meet in order to ensure thatthe occurrence of a double failure was a statistically remoteevent." Gotta love the way those regs protect us... And sure enough it was not statistically remote - it had happened before! "An EMB-110 operated by another UK company suffered two double artificial horizon failures in 1995. The first,on 4 June 1995, involved a double instrument failure" There were only a handful of EMB-110's in the UK... 2) since 2 AIs weren't enough to keep the plane upright (combined with 2 turn and banks, 2 of every other instrument), require passenger planes to have 3 Yes, that's the recommendation. IMO it's unmitigated crap. First off, AI's should not be failing at an average of less than 300 hours. Second, there were still two good PNI's (basically HSI's) and turn&slip indicators. But could the pilots use them? Probably not because "This technique, commonly referred to as 'limited panel' (see paragraph 1.5.3.2) does not form part of a professional pilot's recurrency training and testing." So the most likely causes of the crash are AI failure (quite possibly double AI failure), and the inability of the flight crew to fly partial panel because SURPRISE they get no recurrent training in partial panel flying. Exactly what kind of outcome could one expect when you fit proven failure-prone AI's to an airplane and don't give the flight crew any recurrent partial panel training? (agree, chilling) There are plenty of chilling accidents out there. This isn't one of them. This was inevitable. Michael |
#14
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Big John wrote
Are you trying to tell me it's not easier to fly a PP NDB approach than a PP ILS? If she won't I will - and I've done both, for real, on the same night. Flying the ILS was much easier. I'd like to see you PP trying to use GPS to make an approach. It's hard enough to keep the airplane flying PP without using the benefits of GPS. The last instrument student I taught could consistently fly a partial panel GPS approach (with moving map) with the needle never leaving the donut and with altitude control to +50/-0 ft without breaking a sweat. I instructed for so many years in heavy iron I tend to push the routines I developed to give maximum safety and yet perform the mission. Are you sure they're applicable outside heavy iron? I've never flown any - all my flying and instructing has been singles and light twins (with gliders thrown in for flavor) and I just can't see that a partial panel GPS or ILS would be harder to fly than a partial panel NDB. In fact, my proficiency approach for hoodwork is the night partial-panel single-engine circling NDB, simply because that's the most difficult. A single engine partial panel ILS to Cat II is cake by comparison. Maybe ILS installations have improved... Michael |
#15
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Big John wrote: The soft (silk) white scarf made it easier to keep your head on a swivel like they told you. The British commanders would tell their newbies "It takes three seconds to shoot down another aircraft. So look around every three seconds." George Patterson The optimist feels that we live in the best of all possible worlds. The pessimist is afraid that he's correct. James Branch Cavel |
#17
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G.R.
The brit pretty well said it. Close to what I put up with as a newbe. The old timers in my outfit however wanted you to keep your head moving all the time (and got give a 3 second opening). In the "finger four" we flew in, you didn't clear your own tail. One of the other pilots in flight cleared your tail and you cleared his in combat (loose) formation. And the best. Big John On Mon, 14 Jul 2003 22:03:45 -0400, "G.R. Patterson III" wrote: Big John wrote: The soft (silk) white scarf made it easier to keep your head on a swivel like they told you. The British commanders would tell their newbies "It takes three seconds to shoot down another aircraft. So look around every three seconds." George Patterson The optimist feels that we live in the best of all possible worlds. The pessimist is afraid that he's correct. James Branch Cavel |
#18
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My big, ugly, AN horizon has been working reliably for decades... Makes you
kinda wonder... Denny "Michael" wrote in message om... Sydney Hoeltzli wrote What do you think of the conclusions? |
#19
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Big John wrote:
I also was throwing in the head movements to look at GPS (where ever it is mounted) and then instruments on panel with the high probability of vertigo. If an IFR approach certified GPS requires extensive head movements to follow the CDI, something went badly wrong in the install. The CDI for an approach GPS should not require more head movements than looking at any other CDI. In many installs, it *is* the same CDI as nav radio. Also the communications required on a IFR instrument approach divides your thought process and raises the difficulty. Very true, but wouldn't this apply no matter what approach is being flown? Cheers, Sydney |
#20
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"Sydney Hoeltzli" wrote in message ... Michael wrote: 2) since 2 AIs weren't enough to keep the plane upright (combined with 2 turn and banks, 2 of every other instrument), require passenger planes to have 3 Yes, that's the recommendation. IMO it's unmitigated crap. First off, AI's should not be failing at an average of less than 300 hours. Second, there were still two good PNI's (basically HSI's) and turn&slip indicators. But could the pilots use them? Probably not because "This technique, commonly referred to as 'limited panel' (see paragraph 1.5.3.2) does not form part of a professional pilot's recurrency training and testing." You Have Got To Be Kidding. Are you serious? Yes, I missed that. Are they asserting this shocking hole in proficiency training is widespread? I think you're barking up the wrong tree here. Classic teaching of partial/limited panel involves covering an instrument and then continuing to fly without it. In the case of the Bandeirante accident, that wasn't the issue. There was still a perfectly serviceable AI in the panel, and a pilot sitting in front of it. The issue was identifying the failed instrument in a complex cockpit environment. The chances of being left with no working AI in the panel of a transport aircraft (which starts with 3 AIs) but still having the instrumentation to fly partial panel are so remote that it's not worth the time to train on it. That time is better spent on other exercises, one of them *recognition* of instrument failure. For GA aircraft the situation is different. The probability of ending up with a TC but no AI is much higher, and controlling the aircraft successfully without it is easier. That makes it well worth the practice. Julian Scarfe |
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