@Shalvenay no, it was the other one

The August AAIB bulletin was quite interesting reading: there are two cases of Airbus pilots retracting the flaps instead of the landing gear after take-off

@voretaq7 For IFR training, do they still use Ded Reckoning? Or do they start with something a bit more accurate nowadays (I know very little about this, just starting to learn...)

Oh look, a B707. flightradar24.com/B703/aae81a2

Probably a KC-135 though

@JayCarr we certainly do, because that's all we have available

@DanHulme Really? Using ground references, timers and maths and everything?

@JayCarr yep

but I think in most aircraft it's mainly taught with radionavigation

@DanHulme Are you doing this in IMC or just as an aid to visual navigation?

I'm not doing it in either, but I've seen it done in simulated IMC (with a cover over the helmet visor)

I don't know why, because you really wouldn't want to fly in IMC even if it's legal; probably just to help train precise flying

@DanHulme Wow, you guys take flying WWII trainers very seriously, even using WWII navigational technologies ;). It would be interesting to plot that sort of course. I worry about the winds aloft screwing everything up though.

@JayCarr well, you have an E6B and the winds aloft forecast to calculate your wind corrections

@DanHulme Would you say it's pretty accurate if you factor in the wind correctly?

I don't have any experience of it to say

I mostly want it to be like that scene from "The Hunt for Red October", where the guy says "Give me a stop watch and a map, and I'll fly you through the alps in a plane with no windows" (or something like that.)

yeah, where they're in that trench with all the timed turns

I'm not that brave. But it might be a fun thing to try just to learn a bit more about navigation. Just so long was under the hood, you know, so I can take the hood off at the end and see how close I got.

@DanHulme Yeah, I used to think that was really realistic. But thinking about it these days...I'm sure ocean currents would have messed that up a bit...

if only I could convince one of the more experienced guys in the group to join us on the site

@JayCarr presumably they're more predictable than winds, though

@DanHulme That'd be really cool! Especially if they popped into chat on occassion.

@DanHulme Perhaps, but then again, perhaps not. I mean, it's a fluid, and that's not all that dissimilar to air. And air gets pretty crazy with how winds work and what not. I mean, with the atmosphere the jet stream is pretty predictable, but when you get down towards the ground the terrain makes the winds much harder to figure out.

I wonder if ocean terrain does the same thing? Perhaps the currents that we are used to (on the surface) are more like the jetstream. But underwater, maybe it's more like surface winds and it's much less predictable.

people don't keep building on ocean terrain, though

@DanHulme This is true, but I don't think buildings account for most of the odd winds we find on the surface. I would guess thermal activity, combined with hills and forest and what not probably does more.

I assume underwater would be affected by convection in a similar(ish) manner. But I'm not a fluids expert or an oceanologist (or whatever that is called) so I'm just guessing with what little knowledge I have.

@JayCarr you don't get any of that at the bottom of the ocean, and what you do get is always the same, so my guess is that it's more predictable

@DanHulme Wouldn't the heat on the surface of the ocean cause similar issues though?

Causing hot and cold patches?

but that's already at the top

you get thermoclines in the ocean, and they're already well understood (because sub captains need to use them to stay quiet)

I dunno, the wikipedia article says we're still learning a lot about all of this. I'm going to read through it, suddenly very curious.

@DanHulme Right, but if there are hot patches and cold patches, the cold patches would tend to sink.

I bet a lot of that information is still classified.

Quite possibly

From the article:

"Horizontal and vertical currents also exist below the pycnocline in the ocean's deeper waters. The movement of water due to differences in density as a function of water temperature and salinity is called thermohaline circulation. Ripple marks in sediments, scour lines, and the erosion of rocky outcrops on deep-ocean floors are evidence that relatively strong, localized bottom currents exist. Some of these currents may move as rapidly as 60 centimeters (24 inches) per second."

So it sounds like there is something vaguely like wind, though it also sounds like it's mostly in the deeper parts of the ocean.

but the question is how predictable it is

@DanHulme The next paragraph talks about how it's often modified by obstacles at the bottom of the ocean... That plus the fact that salinity and thermal energy are kind of hard to predict... Lord, now I just want to talk to the scientists in charge of the Argo project. I really don't know how hard it would be to predict localized currents on the ocean floor. But it seems to have the potential to be as difficult as predicting the wind (something that isn't impossible, but isn't easy either)

@JayCarr It's definitely focused more on radio navigation, but ded reckoning is always part of navigation, has been since the days of log, lead, and lookout.

and at altitude the winds are somewhat more reliable than they are down in the boundary layer by the surface.

@voretaq7 Radio navigation using DMEs and such? I'm guessing GPS is still considered "too new" to be the sole way of navigating in IMC.

I only just realized that waypoints don't have actual radio frequencies with them. I'm still trying to figure out how anyone figures out where they are without GPS. I guess if you know where a VOR or NDB is, and you know how far you are from it and your heading....it's just a matter of a little in flight trig.

@JayCarr Nah GPS as sole-source navigation is approved these days - you could theoretically have a com radio and one of the GPS-only Garmins & be good to go.

@JayCarr Waypoints defined without GPS are usually VOR radial & DME distance or the intersection of two radials

@voretaq7 So I can do all of my IFR training (when I get there) via a Garmin?

@voretaq7 That's what I figured. I guess if I had duel VOR receivers, I could use those to figure it out pretty easily.

An IFR-approved panel-mounted Garmin, yes -- interestingly the examiner can only test you on the equipment installed in the aircraft, so if all you have is a VOR/LOC that's all they can test you on

There are stories of DME indicators and ADFs becoming mysteriously INOP on checkride days so the students don't have to fly a DME arc or the NDB approach, but I'm sure all of those were genuine equipment failures and not just the random application of a placard to duck a test element!

@voretaq7 Moral, train on an aircraft with a panel installed Garmin. Actually the local school has two 172s, both with Garmin G500 glass cockpits and Garmin GSN430s for IFR training.

I think that's where I'm going to go for my training.

You can find intersections with one VOR receiver too - helps if it's got a flip-flop button though & you'll never really know exactly where you are, just what intersection you passed...

@voretaq7 Weeeeeee.... So what kind of equipment are you doing your training on?

@JayCarr Whatever's installed in the plane at the time :) (dual VOR + DME right now)

@voretaq7 Are you going to upgrade to a Garmin 430 or 530 or something?

@JayCarr Either the Garmin GTN650 or the Avidyne IFD 440, haven't decided yet

but those are the two main contenders - the GPS King is offering is…kinda crap.

@voretaq7 Having never heard of either of those...I'm going to look them up.

@voretaq7 Ooooo, the 650 has XM satellite weather. That'd be nifty. Kind of wish the screen was bigger, but I guess that's what the 1000 is for, if that's what you want.

the GTNs are the successors to the old GNS systems (430W became the GTN 650, 530W became the GTN 750)

The Avidyne products are clearly "The Apollo GPS engineers left after Garmin bought their shit and went to form their own company. With blackjack, and hookers, and buttons on the panel!"

@voretaq7 Is it as reliable as Bender then, because, you know, I like that Bender guy, but I don't trust him an further than I can throw his shiny metal ass.

@JayCarr The 3 people I know who installed Avidyne units love them, and I must admit I like the way they work in the simulator

Hmm, looking at it again I'd probably want a GTN 750, though that would clearly depend on panel space.

@voretaq7 Which simulator are you using that has both of them?

my only real concern with the Avidyne products is long-term support (not that I trust Garmin's idea of "support" much either, but at least there's gonna be a shit-ton of those on the market if I need to replace it in the future)

@voretaq7 What simulator did you use those on though? Was it just a simulator of the GPS itself, or was it in X-Plane/Prepare3D or some commercial sim?

@TomMcW Congrats!

@JayCarr They make training simulators for all the GPS systems because otherwise you'd kill your battery learning the buttonology on the ground

@TomMcW Didjya puke? :)

@TomMcW Yay!!! First lesson? Or just an introduction?

@JayCarr Just intro. We did a few touch-and-goes. It was very cool.

@voretaq7 Managed to hold it down!

@TomMcW Nice, congratulations! What type of aircraft did you fly?

You know you've read too many FAA counsel interpretations when you start recognizing the writing style of the lawyers.

@Pondlife Twas a C172.

@voretaq7 That is bad. What are you reading about?

@TomMcW Logging PIC as a safety pilot :)

Also I'm once again going off on arrogant pilots who apparently never fly with anyone else in their aircraft

(the "you should never endanger anyone on the ground in an emergency" mentality, taken to the extreme of "land somewhere unfavorable that reduces your chance of survival to spare someone on the ground, even if you've got your wife and kids in the airplane with you")

@voretaq7 Those guys need to get a glider rating :-)

@voretaq7 Well, you obviously don't want to set down on a house, but where are you talking? Like a highway or something?

@TomMcW For me any emergency is a numbers game: I'm going to try to endanger the fewest people possible (so if it's just me in the plane fuck it, I'll land in the water or hit trees if it means avoiding someone on the ground)

When I have people in the plane the risk calculus becomes a LOT more complicated though, and a lot of people like to blindly ignore that we have a responsibility to our passengers (who got in the plane trusting that we'd bring them back alive) just as much as we have to the person on the ground (who didn't sign up to have an emergency airplane dropping out of the sky on their head).

I mean if we take their logic to the extreme the Gimli Glider pilots should have found an unpopulated area to crash in rather than landing at the former-airfield-now-racetrack: That certainly endangered people on the ground, but I think the passengers appreciated being set down on something vaguely runway-like rather than slamming it into the trees somewhere where there shouldn't be any people...

@voretaq7 Sounds reasonable. Your passengers are people too. They deserve consideration

@TomMcW When people piss me off on these discussions I usually point out that 91.13 (basically the only regulation that DOESN'T go away in an emergency) says "another", not "people on the ground", and that passengers are still people other than the pilot/flight crew.

@voretaq7 This isn't the problem you had with the CFII is it?

@voretaq7 Thanks for responding to those the safety pilot / logging PIC comments more politely than I would have.