Autothrust Blue
Welcome aboard the Washington State Ferries
The end of the day is not the appropriate time to get creative.
Vertical path non-precision approach safety?
- Thread starter DE727UPS
- Start date
Autothrust Blue
Welcome aboard the Washington State Ferries
Erm, I'll take cross-pointers hooked up to a flight director/autopilot/HUD to DA(H) any day over chasing around an NDB needle to MDA. I don't feel the need to pound my chest Muton-style in this particular regard. My job is to not expose the people in back to undue risk, and only when I'm satisfied that we won't do something unsafe or uncomfortable, get them to the destination.
Loss of control on a non-precision approach wasn't an unheard-of phenomenon in the fifty-plus years you cite. I can think of more than a handful of airline accidents that came about during a non-precision approach, and these were mustachioed Pan American Skygods.
But whatever.
I'm sure you know every reg like the did the morning of your commercial check ride.
There's no bonus points or street cred if you make flying as hard as possible with least number of tools. Can I fly the plate with the step downs, sure. Why would I though if there is safer method available to me.
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dasleben
That's just, like, your opinion, man
As usual, everything you write is rife with hyperbole. I'm beginning to wonder if you're trolling us.
You seem to write as if we believe dive and drive to be dangerous, i.e. "something only Bob Hoover could do," which we've all told you over and over is not true. There's a broad range on the safe/unsafe spectrum, and while dive and drive flown by a proficient pilot is still on the "safe" side, it's still not quite as far to that side as "VNAV CDA." Should I draw out a graph?
dasleben
That's just, like, your opinion, man
Boris Badenov
Fortis Leader
I'm not sure how it became "hairy-chested tough guy" to be able to fly to the PTS. I don't have any pilot-shirts, my car doesn't have any pilot bumper stickers. I have many interests outside of Aviation (and where the next cheap Chinese Buffet is, which is basically still Aviation). If you didn't go through my drawers (not THOSE drawers, Max), you wouldn't have any idea that my job is operating aviation appliances. In point of fact, I've seen a lot more "I cheat death day in and out" behavior from the lapcats in their 50s who monitor autopilots for a living than I ever have from anyone who might ever be called on to do anything even moderately challenging in an aircraft. Truth be told, I'm a lot more interested in the history of the Roman Republic or, say, the history of Dedekind's evolution of transfinite numbers than I am in transportation appliances.
Flying to the PTS standards isn't to impress anyone. That's not my ego, or my like interior life. That's my job. But I do think that, it being by Job and all, I ought to have the basic proficiency at it which is required and expected by Law. How is this puzzling?
Flying to the PTS standards isn't to impress anyone. That's not my ego, or my like interior life. That's my job. But I do think that, it being by Job and all, I ought to have the basic proficiency at it which is required and expected by Law. How is this puzzling?
flyinguitar
Well-Known Member
I'd say that NDBs are less safe because the ground equipment and needle indications are less reliable. The frequencies they operate at are more susceptible to interference and are not line of sight, leading to occasional madly wobbling needles or steady needles that are inaccurate. I remember the NDB approach at Corvallis, Oregon regularly put us uncomfortably close to high terrain, with "centered" needles placing us markedly deviated from the published final approach course. In IMC I'd rather fly an ILS any day.
When they work out, though, they are beautiful in their simplicity and very satisfying since you know it was a greater degree of your skill that kept the airplane on course.
When they work out, though, they are beautiful in their simplicity and very satisfying since you know it was a greater degree of your skill that kept the airplane on course.
PhilosopherPilot
Well-Known Member
Boris, as we've discussed before, safety is about managing risk, not absence of risk. So safety becomes reducing risk to the lowest possible level, not eliminating it. So if the risks are higher, then by definition the situation is less safe. As has been discussed here, the risks are higher for dive and drive.
So, in the case of airlines that have adopted CANPA or other VNAV non-precision procedures, the risks were unacceptable for dive and drive. Start flying 1,000,000 flights per year, and one in a million starts to look unsavory.
Boris Badenov
Fortis Leader
Well, as has been asserted here, maybe you mean. Why do you imagine that the risks are higher, exactly?
PhilosopherPilot
Well-Known Member
An Internet forum, or message board, is an online discussion site where people can hold conversations in the form of posted messages.
(This quoted from Wikipedia.)
Boris Badenov
Fortis Leader
I had no idea, thanks for informing me.
That, and flying to the PTS. I'm doing rather well for myself, I must say!
In the previous posts I saw only statistical analysis. Certainly that's valuable information, but it doesn't, at least in my jerk mind, explain why flying a non-precision approach is more "dangerous" than flying an ILS. I dunno, maybe you could translate your excuses for incompetence in to Jerkese next time?
BobDDuck
Island Bus Driver
The risks are higher because you are introducing more fail points into the system. As much as I dislike the swiss cheese model, I'm going to use it to illustrate the difference between a constant descent and a dive and drive approach.
Potential fail points both share:
-Setting the wrong MDA
-Not finding the airport and having to go missed
-Course alignment errors
Potential fail points a constant descent has:
-Not getting down in time to see the runway and having to go missed
Potential fail points of a dive and drive:
-Multiple stepdown fixes that could be set wrong
-Multiple large power changes (which is the most likely time for an engine issue to occur)
-Potential for leaving VDP/PDP early and hitting something
-Being unspooled for large portions of the approach during a potential shear situation
-Much higher fuel burn (and noise issues in sensitive areas)
I'm sure I'm missing some, but that is a good starting point.
EVERYTHING we do in aviation is about being safer (not safest obviously, or we'd never go anywhere). If there is a way to make something more safe and not negatively effect the outcome of a flight, we should be doing it. Your argument about the fact that 707 pilots could do it is a straw man, and a poor one at that.
PhilosopherPilot
Well-Known Member
It is more risky to fly dive and drive because instead of flying a stable, uninterrupted constant flight path to the VDP, you are instead changing the flight path from rapid descent to level flight, and then if you see the runway, (hopefully) stable descent to a landing.
As BobDDuck just posted, there are additional considerations as well.
As far as your being a complete jerk is concerned, you really should work on that. This forum is supposed to be a place that we can come and have good discussions, and not get trolled by the likes of you.
As BobDDuck just posted, there are additional considerations as well.
As far as your being a complete jerk is concerned, you really should work on that. This forum is supposed to be a place that we can come and have good discussions, and not get trolled by the likes of you.
Boris Badenov
Fortis Leader
-Setting the wrong MDA - So, like, it's somehow easier to set the wrong MDA than the wrong DH? They're both in black and white on the plate.
-Not finding the airport and having to go missed - How is this more likely on an non-precision than a precision approach?
-Course alignment errors - Wait, so they're more dangerous because you might forget to read the plate and make the number in the little window match the number on the piece of paper? Maybe you'd "find your bliss" better as a Sanitation Engineer?
Potential fail points a constant descent has:
-Not getting down in time to see the runway and having to go missed - GO MISSED? My God, that's basically an accident right there! Also, expecting a pilot to get the aircraft to an appropriate altitude before commencing an instrument approach is "difficult"? Consult aforementioned PTS. Amazing anyone ever gets a rating!
Potential fail points of a dive and drive:
-Multiple stepdown fixes that could be set wrong - Yeah, it's pretty tough to look at the DME or God Forbid set a cross radial. If you could do that right every time, you'd be in third grade! I'm not in third grade, are you!? Dangerous.
-Multiple large power changes (which is the most likely time for an engine issue to occur) - Looking forward to your litany of accidents which have occurred because some poor bastard was forced to move the power levers during an approach!
-Potential for leaving VDP/PDP early and hitting something - Again, reading is pretty hard.
-Being unspooled for large portions of the approach during a potential shear situation - This should be another long list of accident abstracts. I'll just get me reading glasses.
-Much higher fuel burn (and noise issues in sensitive areas) - Well that does seem dangerous.
Howso? It seems to me to be a direct refutation of the claims that it would be somehow absurdly dangerous to shoot a step-down approach in a large aircraft with slow-spooling jet engines? Cause, I mean, your high-bypass turbofans are Le Mans next to the ole straight pipes, by all accounts.
Boris Badenov
Fortis Leader
You should contact Dough on this subject, then. I'll cheerfully tie my little bag to my stick and take the next train for wherever when he tells me I'd best be on my way because I've offended the sensibilities of some self-impressed, self-described "philosopher-pilot" who doesn't seem to have any formal education in philosophy to speak of or know much of anything about flying.
PhilosopherPilot
Well-Known Member
You just don't get what safety is all about. You keep showing your ignorance, post after post.
I forgot, you never make mistakes. Errors are not inevitable in your world, and those who make them are inadequate pilots.